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evaluation of brassicas in grazing systems for sheep: ii. blood composition and nutrient status.blood composition of lambs grazing brassicas and stockpiled grass or grass-clover pastures in the fall of 4 yr was monitored to assess possible effects of plant metabolites (e.g., glucosinolates, s-methyl cysteine sulfoxide) on health and performance. serum thyroxine (t4) concentrations in lambs grazing brassicas decreased upon initiation of grazing, with a subsequent recovery, and concentrations were increased by oral dosing with i or i+cuo. serum triiodothyronine (t3) increased gradually with ...19947928763
thyroid hormone replacement restores circulating enkephalin concentrations in hypophysectomized fetal sheep.we have investigated the effects of fetal hypophysectomy (hx) with or without thyroxine (t4)replacement on the plasma concentrations of free methionine-enkephalin (free met-enk), noradrenaline, and adrenaline in late gestation sheep fetus. plasma adrenaline concentrations were significantly higher in intact fetal sheep (1.05 +/- 0.12 pmol/l) between 125 and 140 days of gestation when compared with the hx + saline (0.64 +/- 0.10 pmol/l) and hx + t4 (0.61 +/- 0.08 pmol/l) groups. during the first ...19947931290
effect of pinealectomy upon the nonspecific immune response of the ring-dove (streptopelia risoria).the different stages of the phagocytic process by granulocytes of pinealectomized or sham-pinealectomized ring doves (streptopelia risoria) as well as hematological parameters (total white blood cells, smear, and total protein) and serum hormone levels (triiodothyronine (t3), thyroxine (t4), and corticosterone) were studied. a number of immunological parameters of the phagocytosis process, including adherence capacity, mobility rate, the phagocytosis capacity for inert particles and the digestio ...19947932039
effect of anterior hypothalamic area lesions on photoperiod-induced shifts in reproductive activity of the ewe.the areas of the brain involved in photoperiodic control of reproduction are not well defined. the objective of this study was to determine whether anterior hypothalamic area (aha) lesions in the ewe affected the responses of the reproductive system to shifts in the length of the daily photoperiod and development of photorefractoriness to a constant short day photoperiod. eleven intact ewes received bilateral radiofrequency lesions of the aha (ahax), and five received sham lesions (sham). the ew ...19947956905
influence of low-level exposure to fusarium mycotoxins on selected immunological and hematological parameters in young swine.the effects of low dietary concentrations of fusarium mycotoxins (deoxynivalenol (don), 15-acetyl-don, and zearalenone) on growth, immunological, and hematological parameters were determined in young pigs during a 28-day feeding experiment. clean and naturally contaminated corn were incorporated into basal diets formulated to contain 0.00, 0.75, 1.50, and 3.00 mg don/kg diet. a pair-fed control animal was used for comparison with each animal receiving the highest level of contamination (diet 4). ...19947958555
a central negative feedback action of thyroid hormones on thyrotropin-releasing hormone secretion.two experiments were conducted to test the hypothesis that thyroid hormones exert central negative feedback effects on the secretion of trh from the hypothalamus in the ewe. in the first experiment, we examined the effects of thyroidectomy on the secretion of trh and tsh. thyroidectomy was followed by an unambiguous increase in trh in pituitary portal plasma and tsh in the peripheral circulation. in the second experiment, we tested the effects of t4 replacement to thyroidectomized ewes. t4 repla ...19947988422
metabolism of sulfoconjugated thyroid hormone derivatives in developing sheep.although the production of thyroxine (t4) in the developing ovine fetus ranges from 20 to 50 micrograms.kg-1.day-1, production rates for 3,5,3'-triiodothyronine (t3) average only 1-2 micrograms.kg-1.day-1, whereas reverse t3 (rt3) production rates approach 5-6 micrograms.kg-1.day-1. thus the fate of the majority of fetal t4 production is uncertain. recently we have reported significant concentrations of various thyroid hormone sulfoconjugates in serum and other fetal compartments. in the present ...19948023919
new robertsonian translocation chromosomes in domestic sheep (ovis aries).we report two new robertsonian centric fusions, designated t4 and t5, in new zealand romney sheep. q- and g-banding studies show that sheep chromosomes 5 and 8 are fused in t4 and that chromosomes 8 and 22 are fused in t5. the presence of large blocks of centromeric heterochromatin in t4 and t5 suggests that the fusions may be of recent origin.19948039424
acute or chronic immunoneutralization of somatostatin does not affect growth hormone or thyroid hormone secretion in sheep.the effect of acute or chronic immunoneutralization of somatostatin (srif) on plasma gh, thyrotrophin (tsh) and thyroid hormones was examined. acute responses to srif immunoneutralization were examined using 30 intact male lambs (19.8 +/- 0.6 kg) assigned to one of five treatment groups such that control (c) lambs received no anti-srif immunoglobulin and srif-immunized (si) lambs received 2 mg (si2), 10 mg (si10), 20 mg (si20) or 100 mg (si100) anti-srif immunoglobulin/kg body weight (bw). contr ...19938096234
toxins from the box-jellyfish chironex fleckeri.two myotoxins (t1 and t2) with mol. wts of approximately 600,000 and 150,000, respectively, and a haemolysin (t3) with a mol. wt of approximately 70,000 were isolated from the crude nematocyst venom of c. fleckeri by the use of sephadex g-200 chromatography. a neurotoxic fraction (t4) and a haemolytic fraction (t5) containing proteins with apparent mol. wts of approximately 150,000 and 70,000, respectively, were also isolated by sephadex chromatography from crude extracts of tentacular material ...19938099238
pasteurella haemolytica serotypes isolated in northern ireland during 1989-1991.pasteurella haemolytica isolates from clinical veterinary samples were serotyped over a three year period to determine the distribution of strains in northern ireland, to compare the results with the recorded distribution in the remainder of great britain and to extend information on the geographical prevalence of the serotypes. four hundred and nine typable and 91 untypable strains were isolated from 490 animal cases. from 127 typable cattle isolates, the commonest serotype was a1, most frequen ...19938111616
immunologic and endocrine effects of the flame-retardant pentabromodiphenyl ether (de-71) in c57bl/6j mice.polybrominated diphenyl ethers are manufactured for use as flame retardants in commercial plastics and textiles in europe and north america. these studies investigated the acute and subchronic immunotoxicity and endocrine effects of a commercial pentabromodiphenyl either mixture, de-71, in female c57bl/6 mice. mice were orally exposed to acute single doses of de-71 of 0, 0.8, 4.0, 20, 100, or 500 mg/kg, or to subchronic daily doses totaling 0, 250, 500, or 1000 mg/kg over a 14 day period. immuno ...19948134923
changes in fetal thyroid hormone levels in adrenalectomized fetal sheep following continuous cortisol infusion 72 h before delivery.continuous infusion of cortisol into adrenalectomized fetal sheep during the last 72 h of gestation (term = 145 +/- 2 days) produced a significant (p < 0.05) rise in fetal serum tri-iodothyronine (t3) mean +/- s.e.m. concentrations from 398 +/- 65 to 1340 +/- 238 ng/l. a concurrent decrease in plasma thyroxine (t4) levels was observed in three out of four animals. no significant changes in the concentrations of either hormone were noted prior to the start of cortisol infusion. the plasma concent ...19948138755
defective thyroglobulin synthesis and secretion causing goiter and hypothyroidism.the integrity of the tg structure as a protein is essential for adequate synthesis of thyroid hormone. also a large supply of iodine and of thyroid hormone is stored into the tg molecule and available for secretion on demand. mutations in tg gene or hyposialylated tg due to a defective sialyltransferase activity would cause a structurally defective protein and severely impair the functional ability of tg. in this review we attempt to cover the abnormalities in the synthesis of tg described in bo ...19938325250
[alkaline phosphatase during the puerperium in ewes and its relation to thyroid hormones and ovarian steroids].triacylglycerols as the sources of cholesterol, the primary precursor of steroid synthesis, are one of the factors that limit the speed of steroidogenesis. synthesis and resynthesis of triacylglycerols depend, in addition to other factors, on phosphatid hydrolysis that is controlled during pregnancy by placentary alp (sumikawa et al., 1987) and the ffa pool in the systemic blood stream. enzymes participating in ffa release from the fat tissue are affected by thyroid hormones and tsh (mayes, 1977 ...19938346621
effects of prolactin, growth hormone, and triiodothyronine on prolactin receptors in larval and adult tiger salamanders (ambystoma tigrinum).the effects of porcine growth hormone (pgh) or ovine prolactin (oprl) alone and in combination with triiodothyronine (t3) on renal prl receptors were determined in both pre- and post-metamorphic tiger salamanders (ambystoma tigrinum). the protein hormones were given at a dose of 1.0 micrograms/gm body weight/day and the t3 was given at 10.0 ng/gm body weight/day. the duration of treatment was 7 days. effects on growth, and plasma thyroid hormone levels were also determined. ovine prl increased g ...19938354992
modified responses of circulating cortisol, thyroid hormones, and glucose to exogenous corticotropin and thyrotropin-releasing hormone in food-deprived sheep.in a previous experiment, food deprivation was found to suppress the increase of plasma cortisol and thyroid hormones in stressed animals. because both the hypothalamo-adrenocortical and the thyroid axes are stimulated during stress, we investigated in this study whether a similar pattern of changes occurs in food-deprived sheep following corticotropin (acth) or thyrotropin-releasing hormone (trh) administration. each hormone was given as a bolus injection on the fifth day of food deprivation. b ...19938392731
failure of bilateral paraventricular nuclear lesions to cause hypothalamic hypothyroidism in fetal sheep.concentrations of t4 indicative of a hyperthyroid state are present in fetal sheep plasma between 100 days gestational age (dga) and parturition. fetal pituitary stalk section studies indicate that, as in adults, these high fetal plasma t4 concentrations during pregnancy are controlled by the hypothalamus. we compared peripheral plasma t4 concentrations in fetal sheep with bilateral hypothalamic paraventricular nuclear (pvn) lesions (lesion group; n = 5) to fetal sheep with sham-pvn lesions (sha ...19938419135
the decreased immune responses in macular mouse, a model of menkes' kinky hair disease.the macular mutant mouse is a murine model of the menkes' kinky hair disease, characterized by a copper deficiency in serum. the immune response of its hemizygote (ml/y) was examined, herein. ml/y mice which were not treated with cu were atrophy of lymphoid tissues on day 14. however, kidney, brain, heart and lung weights were higher in ml/y mice without cu treatment than in normal (+/y) mice. when compared to cells from +/y mice, spleen cells from ml/y mice exhibited similar proliferation-curve ...19938434133
the role of thyroidal type-i iodothyronine deiodinase in tri-iodothyronine production by human and sheep thyrocytes in primary culture.we have studied the origin of tri-iodothyronine (t3) secreted by human and sheep thyrocytes in primary culture and also the expression of type-i thyroidal iodothyronine deiodinase (id-i) in the thyroid and liver of man and various other animals. inhibitors of id-i reduced t3 secretion from human but not sheep thyrocytes. in contrast, inhibitors of de-novo thyroid hormone synthesis reduced both thyroxine (t4) and t3 production in sheep thyrocytes, but had no effect on the t3 secreted by human thy ...19938473826
effects of hypothyroidism with treatment of an anti-thyroid drug, propylthiouracil on immune responses in chickens.the effect of a wide range of doses of propylthiouracil (ptu, 0.01-5%) on the immune responses of young male chickens was examined. one-day-old chickens were rendered hypothyroid by ptu supplemented in the feed for 4 weeks. at all doses ptu treatment caused a significant dose-related reduction in body weight (except at 0.01%) and in relative lymphoid organ weights. skin response to phytohemagglutinin (pha) was significantly greater in the chickens treated with low doses of ptu (0.01-0.1%) and si ...19938475619
radiographic study of postnatal development of the tarsus in west african dwarf goats.seven goats of the west african dwarf breeds, three females and four males, from the same farm were studied by serial radiography from the first week of life and at 3, 6, 9, 16, 23, 28, 37 and 46 weeks of age. the radiological appearance of the developing tarsus as evaluated from radiographs is described. during the first week postnatally, eight loci were observed to be partially ossified. the talus, tarsi centrale (tc), first (t1), second (t2), third (t3) and fourth (t4) tarsal bones had each a ...19938489044
postnatal cardiovascular and metabolic responses to a single intramuscular dose of betamethasone in fetal sheep born prematurely by cesarean section.although the benefits of antenatal hormone treatment are well accepted, most studies have reported only pulmonary effects. there is evidence of beneficial cardiovascular and metabolic effects in studies using chronically catheterized animals; however because of the route of administration, the results are not directly applicable to clinical strategies. we previously demonstrated significant pulmonary effects in animals treated antenatally with a single, direct fetal, intramuscular injection of g ...19958552438
[seasonal effect on serum levels of thyroid hormones in german shepherds and dachshunds and their health status].a relatively frequent prevalence of dermatoses in summer has drawn our attention. dermatoses of endocrine origin occur very often. we have noticed the deterioration of skin changes in animals with hypothyroidism. bubeník et al. (1983), webster et al. (1991), reiter et al. (1988) reported that changes in concentrations of thyroid hormones were found in fallow-deer, sheep and hamsters due to the effect of temperature and season. based upon this knowledge we have decided to observe the health statu ...19958585138
[the effect of carbimazole on lactate dehydrogenase isoenzymes and thyroid hormone levels in sheep].the oxidative processes in the organism are activated by hormones of the thyroid gland. the pyruvate-lactate component catalyzed by lactate dehydrogenase presents one of the important oxidic-reductive systems in the animal organism of biochemical importance (ec. 1.1.1.27). in certain cases of the thyroid gland disturbances antithyroid drugs, such as derivatives of thiouracil, mercaptoimidazole and some others may be used for the treatment of men and animals (marchant et al., 1979; negwer, 1987). ...19958659086
[thyroid and ovarian hormones in ewes treated with gestagens and pmsg in the spring season].recent experimental observations have shown that the thyroid gland plays a dominant part in the induction and maintenance of anoestrus in ewes. the mechanisms of the anoestrous effects of the thyroid gland are still unclear. on the basis of experiments, in which after thyroidectomy at the onset of sexual activity lh production was maintained also during the spring months, iodothyronines have been supposed to stimulate the inhibitory effects of oestrogens upon the neuroendocrine centres that gene ...19958659087
brown adipose tissue and liver development during early postnatal life in hand-reared and ewe-reared lambs.this study examined the effects of modest changes in ambient temperature in hand-reared lambs (experiment one) and in ewe-reared lambs (experiment two). lambs were killed at either 8 or 31 days of age and perirenal adipose tissue was identified as being brown adipose tissue (bat) from measurements of thermogenic activity (i.e. gdp binding to uncoupling protein in isolated mitochondria) or thermogenic capacity (i.e. detection of uncoupling protein by immunoblotting). in addition, type i and ii io ...19968713733
differing patterns of mechanical response to direct fetal hormone treatment.a single combined intramuscular dose of betamethasone and l-thyroxine (t4) or placebo was injected into the shoulder of fetal lambs 48 hours prior to delivery at days 121 (n = 14), 128 (n = 25) or 135 (n = 20) of gestation. respiratory mechanics were calculated using multiple linear regression analysis. both respiratory system resistance (rrs) and elastance (ers) decreased approximately 4 fold between gestational days 121 (d121) and 135 (d135). both variables were also reduced by hormone treatme ...19968738903
serum igg and igm responses to sheep red blood cells (srbc) in weaned calves fed milk supplemented with zn and cu.because ruminants have a syndesmochorial placenta, the neonates are agammaglobinaemic and prone to morbidity and mortality from opportunistic infections. only temporary benefit in passive immunity transfer from mother to offspring is derived from feeding colostrum to neonates. the serum immunoglobulin (ig) g and igm responses to challenges with sheep red blood cells (srbc) were investigated in calves fed milk supplemented with zinc, copper, or both. twenty crossbred calves, weaned on day 5, were ...19958748260
experimental granulomatous vasculitis induced by sensitization with ascaris suum antigen in mice.experimental sensitization by repeated intramuscular injection of ascaris suum antigen (ag-as) supplemented with freund's incomplete and complete adjuvants was carried out in 50 balb/c crsl c male mice (sensitized group) for 24 weeks, and the results were compared with those in a control group of 25 mice. at the injection sites of the sensitized group, granulomatous angiitis with eosinophil infiltration was observed in all mice, and fibrinoid angiitis in only four. by light and electron microsco ...19958808296
the role of the pituitary-thyroid axis in the developmental regulation of enkephalin-containing peptides in the superior cervical ganglia and adrenal of the fetal sheep.we have postulated that sympathetic neurones may be one source of circulating enkephalins in the fetus. therefore, we have investigated the effects of increasing gestational age on the content of the enkephalin-containing peptides in the superior cervical ganglia (scg) of the fetal sheep during late gestation. we have also investigated the role of the pituitary-thyroid axis in the coordinate regulation of enkephalin-containing peptides within the fetal sympathoadrenal system. we found an increas ...19968816363
thyroxine replacement after hypophysectomy alters the pattern of enkephalin localisation in the adrenal medulla of the fetal sheep.it has been suggested that a pituitary-derived or -dependent factor may suppress enkephalin peptide synthesis in the central noradrenaline- containing cells of the sheep adrenal medulla in late gestation. we have investigated the effect of thyroxine (t4) replacement after fetal hypophysectomy on the localisation of enkephalin peptides within the peripheral adrenaline- and central noradrenaline-containing regions of the adrenal medulla of the fetal sheep. fetal hypophysectomy (hx) was performed i ...19968816366
effect of selection for lifetime production of lamb weaned on hormonal factors that affect growth in targhee ewes and lambs.targhee ewes (n = 22, average age 5 yr) rearing twin lambs were used to investigate serum growth hormone (gh), igf-i, triiodothyronine (t3), thyroxine (t4), and prolactin (prl; ewes only) concentrations associated with selection pressure for lifetime production of kilograms of lamb weaned per ewe. period 1 started on d 4 after birth and was conducted in confinement. periods 2, 3, and 4 were conducted on fenced intermountain sagebrush-bunchgrass range starting at an average of 49, 84, and 112 d a ...19968880417
single dose fetal betamethasone administration stabilizes postnatal glomerular filtration rate and alters endocrine function in premature lambs.these studies determined the effects of fetal treatment with betamethasone alone, or in combination with thyroid hormone (thyroxine; t4), on postnatal renal and endocrine adaptations in preterm newborn lambs. ovine fetuses (126 d of gestation; term = 150 d) received single, ultrasound-guided intramuscular injections of saline, 0.5 mg/kg betamethasone (celestone soluspan, or 0.5 mg/kg betamethasone plus 60 micrograms/kg t4. after 48 h, lambs were delivered, treated with surfactant (survanta, 100 ...19968910927
cyclosporine a immunosuppression in sheep with response enhancement by concomitant ketoconazole.1. the pharmacokinetics of a single dose of cyclosporine a (csa) administered to sheep by intravenous (i.v.) route were examined. 2. concomitant administration of ketoconazole was found to increase the area under the blood csa concentration-time curve (auc) and was effective when administered by the oral or intraperitoneal route. 3. the effects of csa and ketoconazole on the immune system of sheep were also assessed. 4. a single dose of csa 5 mg/kg resulted in abrogation of in vitro lymphocyte f ...19968911716
evidence of a thyrotropin-releasing activity of ovine corticotropin-releasing factor in the domestic fowl (gallus domesticus).ovine corticotropin-releasing factor (ocrf) administered to 19-day-old chicken embryos (e19) increased plasma concentration of pituitary glycoprotein alpha-subunit concentrations within 15 min for at least 4 hr. follicle stimulating hormone levels were unchanged, while plasma luteinizing hormone concentrations only began to increase 1 hr after the ocrf treatment. calculation of circulating thyrotropin (tsh) indicator values revealed a rapid elevation in tsh plasma levels following ocrf. concentr ...19968930604
effects of maternal thyroid status on thyroid hormones and growth in congenitally hypothyroid goat fetuses during the second half of gestation.congenital hypothyroidism in dutch goats is due to a thyroglobulin (tg) synthesis defect that is inherited in an autosomal recessive manner. minute amounts of mutated tg messenger rna are translated into glycosylated tg fragments that contain the n-terminal hormonogenic site and are able to form t4, albeit less efficiently. we analyzed the effects of maternal thyroid status on fetal plasma thyroid hormones and growth during the second half of gestation (e90-e150). maternal hypothyroidism, presen ...19978977378
thyrotropin expression in hypophyseal pars tuberalis-specific cells is 3,5,3'-triiodothyronine, thyrotropin-releasing hormone, and pit-1 independent.the expression of tsh subunit genes (tsh alpha and -beta) in pituitary thyrotropes is primarily regulated via circulating thyroid hormone levels (t3) and the hypothalamic trh. hypophyseal pars tuberalis (pt)-specific cells also express both hormonal subunits of tsh, but do not resemble thyrotropes of the pars distalis (pd) with respect to their distinct morphology, secretion, and direct modulation of tsh expression by photoperiodic inputs and melatonin. to investigate whether this distinct regul ...19979048604
reproductive seasonality of corriedale rams under extensive rearing conditions.the objective of the present study was to describe seasonal changes in scrotal circumference (sc), live weight (lw), sperm morphology and plasma levels of testosterone (t) and thyroxine (t4) in young corriedale rams reared under extensive conditions typical for the southern latin american region. a total of 31 corriedale rams, 11 months of age and with a lw of 36 +/- 1.1 kg and (sc) of 23.0 +/- 0.5 cm at the beginning of the experiment (september) were kept on natural pastures. at monthly interv ...19979129352
influence of an antiprogestin (onapristone) on in vivo and in vitro fertilization.the effects of a progesterone antagonist (onapristone) on heat synchronization, luteinizing hormone (lh) surge, ovulation, oocyte maturation and fertilization of superovulated ewes were studied. its effects on in vitro bovine oocyte maturation and fertilization were also studied. estrus synchronization and superovulation treatments were applied to 39 adult ewes using an intravaginal sponge with fluorgestone acetate for 9 days with injections of prostaglandin f2 alpha and pregnant mare's serum go ...19979231247
a critical period for thyroid hormone action on seasonal changes in reproductive neuroendocrine function in the ewe.thyroid hormones are obligatory for the annually recurring termination of reproductive activity in a spectrum of seasonal breeders, including sheep. previous studies involving thyroidectomy and t4 replacement have led to the hypothesis that, in the ewe, thyroid hormones are necessary only during a limited interval late in the breeding season for the neuroendocrine processes that cause the transition to anestrus. the present series of experiments tested this hypothesis by assessing the influence ...19979231794
plasma concentration of thyroid hormones in lambs fed poultry offal meal in replacement of soybean meal at two energy levels.sixty growing najedi ram lambs (23.5 kg bw: 3 months old) were divided randomly to 6 equal groups. each group was fed on different (isonitrogenous) diet, being either high energy (2.79 mcal me/kg dm) or low energy (2.15 mcal me/kg dm), supplemented with either 0.5 or 10% poultry offal meal (pom) in replacement of an equal amount of soybean meal (sbm). feeding was ad libitum for 15 weeks experimental period. thyroid hormones levels in plasma were determined during the last 7 weeks of the experime ...19979239951
genetic relationships among pasteurella trehalosi isolates based on multilocus enzyme electrophoresis.genetic diversity among 60 british pasteurella trehalosi isolates representing the four recognized capsular serotypes, t3, t4, t10 and t15, and recovered predominantly from sheep suffering from systemic pasteurellosis, was estimated by analysing electrophoretically demonstrable allelic variation at structural genes encoding 19 enzymes. thirteen of the locl were polymorphic and 20 distinctive multilocus genotypes (electrophoretic types, ets) were identified. the population structure of p. trehalo ...19979274038
prenatal glucocorticoid and t4 effects on lung morphology in preterm lambs.prenatal glucocorticoid plus t4 treatment of fetal sheep results in improvements in oxygenation, gas exchange, lung mechanics, and lung volumes after preterm delivery. we have evaluated the morphometric changes in the lungs of lambs exposed to betamethasone and t4 48 h before preterm delivery at 121 and 135 d gestation and related those changes to the physiologic improvements in lung function. the lungs used for the morphometric studies were from lambs with postnatal physiologic responses simila ...19979279249
effects of induced hypo- and hyperthyroidism on immune function and plasma biochemistry in mallards (anas platyrhynchos).hypo- or hyperthyroid states were induced in adult male mallards (anas platyrhynchos) by subchronic exposure to daily injections of methimazole or a 9:1 ratio of thyroxine (t4): triiodothyronine (t3). the levels of t4 given were 0, 125, 250, or 500 micrograms/kg/day and for methimazole; 10 mg/kg/day for 22 or 21 days. plasma t3 showed a lasting decrease with t4:t3 treatment, despite the attempt to maintain the normal t4:t3 ratio. antibody formation to sheep red blood cells was decreased only at ...19979440248
seasonal variation in live weight, testes size, testosterone, lh secretion, melatonin and thyroxine in merino and corriedale rams in a subtropical climate.in the present investigation we studied the seasonal changes in live weight and testes and pituitary activity in merino and corriedale rams in a subtropical climate. testes activity was measured as scrotal circumference (sc), plasma concentration of testosterone (t) and release of testosterone after exogenous gnrh injection. lh pulsatility and pituitary lh responsiveness to exogenous gnrh was measured as an index of pituitary activity. in addition, we wanted to characterize the seasonal pattern ...19989592944
antenatal triiodothyronine improves neonatal pulmonary function in preterm lambs.to characterize 1) pulmonary gas exchange, 2) pulmonary function, 3) lung fluid and tissue phospholipid content, and 4) thyroid hormone in the premature lamb (0.85 of term) after intra-amniotic administration of 100 micrograms of triiodothyronine (t3) 2 weeks before delivery.19989614640
endocrine and reproductive function in ewes exposed to the organochlorine pesticides lindane or pentachlorophenol.the effects of lindane (lin, gamma-hexachlorocyclohexane) and pentachlorophenol (pcp) on reproduction and general endocrine function were examined in breeding ewes as a model for wild and domestic ungulates, which may be exposed to low levels of pesticides that are potential endocrine-disrupting chemicals. ewes (n = 13/group) were fed either a control untreated diet (con), or a diet treated with lin (1 mg/kg/d) or pcp (1 mg/kg/d) during the 5 wk prior to mating and throughout pregnancy and lacta ...19999923752
thyroid hormones act primarily within the brain to promote the seasonal inhibition of luteinizing hormone secretion in the ewe.in the ewe, thyroid hormones are required for the seasonal suppression of gnrh and lh secretion, thereby maintaining an annual rhythm in reproductive activity. the primary site of action of thyroid hormones is unknown; in particular, there is no evidence to distinguish a central from a peripheral action. in this study, we test the hypothesis that thyroid hormones can act directly within the brain to promote gnrh/lh seasonal inhibition. ovariectomized estradiol-treated ewes were thyroidectomized ...199910067833
lung morphometry and collagen and elastin content: changes during normal development and after prenatal hormone exposure in sheep.this study examined whether the improvement in lung function after prenatal hormone exposure coincided with changes in lung morphometry or in collagen and elastin content. fetal lambs received a single intramuscular injection of betamethasone (0.5 mg/kg) plus l-thyroxine (t4) (15 micrograms/kg) or vehicle control 48 h before delivery at 121, 128, or 135 d gestational age (d 121, d 128, d 135, term = 150 d). t4 was administered in conjunction with betamethasone in an attempt to enhance the matura ...199910231854
serotypes and electrophoretic protein profiles of pasteurella haemolytica isolated from pneumonic ovine lungs.serotypes and sds-page protein profiles of p. haemolytica isolated from pneumonic ovine lungs were investigated. of 268 p. haemolytica isolates, 232 (86.6%) were serotypable. a total of 12 serotypes were recognized in 20 different geographic origins of central turkey. the most common serotype was a2, followed by a7, a1 and t4. serotypes a13, a14, a16 and t15 could not be detected. in sds-page, marked differences between major bands of biotype a and t strains were found. in numerical analysis of ...199910379102
thyroid function and effects on reproduction in ewes exposed to the organochlorine pesticides lindane or pentachlorophenol (pcp) from conception.there is concern over the potential endocrine-modulating effects of long-term exposure to pesticides. in this study, ewe lambs were exposed to lindane and pentachlorophenol (pcp) from conception to necropsy at 67 wk. of age. the ewe lambs (and their mothers) were given untreated feed (n = 6) or feed treated with 1 mg/kg body weight/day of lindane (n = 8) or pcp (n = 13). estrus was synchronized at 32 wk. of age, and ewe lambs were exposed to vasectomized rams. ewe lambs were then exposed to inta ...199910632142
serum luteinizing hormone, testosterone, and thyroxine and growth responses of ram lambs fed locoweed (oxytropis sericea) and treated with vitamin e/selenium.sixteen ram lambs (5 m.o. old, 45 +/- 1.5 kg) received a control diet (50% concentrate, no locoweed, n = 4), locoweed (20% locoweed for 21 d, n = 4), muse (2 ml i.m. of muse containing 5 mg selenium and 50 mg vitamin e/ml, n = 4) on days 21 and 35([day 0 = first day of trial]), or locoweed + muse (n = 4). the rams were maintained in individual pens (3 x 9 m) with free access to feed, water, salt and shade. on day 7 after initiating locoweed, serum alkaline phosphatase (ap) increased (p < 0.01), ...199910735112
long-term alterations in adiposity affect the expression of melanin-concentrating hormone and enkephalin but not proopiomelanocortin in the hypothalamus of ovariectomized ewes.we have developed a ruminant model to study long-term alterations in adiposity on the expression of appetite-regulating peptides in the hypothalamus. in this model endocrine and metabolic status are fully defined as well as body composition. the current study sought to define the effects of altered adiposity on the expression of genes for neuropeptide y (npy), pomc, enkephalin (enk), and melanin-concentrating hormone (mch). ovariectomized ewes with high (60 +/- 1 kg) (fat) or low (37 +/- 3 kg) b ...200010746657
effect of feeding level and thyroxine on adipose tissue development and growth in postnatal lambs.we investigated the influence of exogenous thyroxine (t4) administration in conjunction with level of feeding on adipose tissue and liver growth in postnatal lambs. pairs of lambs were fed either 100 g (i.e. low fed) or 200 g (i.e. high fed) of milk powder per litre of reconstituted milk replacer over the first month of life. half of the pairs of lambs were fed a bolus dose of t4 (15 mg (kg body weight)-1) daily until 8 days of age. perirenal adipose tissue and hepatic tissue were sampled at eit ...200010919873
physiological responses of pre-ruminant kid goats and lambs to different environmental temperatures.the purpose of this study was to establish the metabolic behaviour of both preruminant kid goats and lambs, when they are kept at different environmental temperatures (12, 24 and 30 degrees c). the animals were fed ad libitum with a milk replacer for the first two months of life. blood samples were taken from all the animals on days 30, 40, 50 and 60 post partum, to determine serum levels of glucose, insulin, free fatty acids, triiodothyronine (t3) and thyroxine (t4), both when fasting and 4 hou ...200011198159
effect of climate on the seasonal endocrine profile of native and crossbred sheep under semi-arid conditions.thirty-four 2-year-old ewes, of which 17 were native (chokla) and 17 were avivastra (chokla 67.5% x 32.5% rambouillet) breeds of similar body weights, were selected. both groups were maintained under the same management conditions with 8 hours daily grazing. in addition to grazing, each ewe received 300 g/day of a concentrate mixture comprising crude protein 20% and 70% total digestible nutrients. the ewes of both breeds were not mated during the study. the daily environmental parameters were re ...200111360802
inflammatory response, growth, and thyroid hormone concentrations are affected by long-term boron supplementation in gilts.an experiment was conducted to determine the long-term effects of dietary boron (b) on growth performance, immune function, and plasma and serum characteristics in gilts. fifty weanling gilts were allotted to 10 pens based on weaning weight and litter origin. pens were randomly assigned to receive one of two dietary treatments. treatments consisted of a basal diet low in b (control) and the basal diet supplemented with 5 mg b/kg diet as sodium borate. gilts remained on their respective experimen ...200111424693
comparison of immune parameters of sheep with naturally high or low plasma concentrations of melatonin.studies in rodents and humans have suggested that the pineal gland and its secretory product melatonin play an important role in the modulation of the immune system. in this study, we tested the hypothesis of a difference in immune parameters between ewes with naturally high vs. low circulating melatonin. thus, two comparable groups of 10 ile-de-france sheep were selected from a large flock, for their naturally high and low plasma concentrations of melatonin. the mean plasma melatonin concentrat ...200111589760
fetal and maternal thyroid hormone responses to ethanol exposure during the third trimester equivalent of gestation in sheep.abnormal thyroid hormone system function in the mother or fetus during pregnancy can result in brain defects, some of which resemble those found in children with fetal alcohol syndrome. it has been hypothesized that ethanol may act to mediate alcohol-related birth defects in part by altering thyroid hormone system function. we investigated whether a binge pattern of maternal ethanol consumption over the last trimester equivalent of gestation in sheep results in an alteration in fetal or maternal ...200211821654
zinc supplementation decreases total thyroid hormone concentration in small ruminants.the effect of dietary zinc (zn) supplementation on plasma zn and serum thyroid hormones was evaluated in healthy male merino lambs and angora goats. a total of 12 lambs and 12 goats were divided into two equal groups as control and zn groups in separate experiments. the lambs and goats of the control groups were fed basal rations alone. the zn contents of these rations prepared for lambs and goats were 40 mg/kg and 35 mg/kg in dry matter (dm), respectively. both species of animals in the zn grou ...200212061240
diversity of mannheimia haemolytica and pasteurella trehalosi serotypes from apparently healthy sheep and abattoir specimens in the highlands of wollo, north east ethiopia.the prevalence and serotypic diversity of mannheimia [pasteurella] haemolytica and pasteurella trehalosi from nasal swabs, sera and abattoir specimens from sheep in the highlands of wollo, north east ethiopia was investigated. prevalence rates of 83% and 75% of these microorganisms were found in the serum samples and nasal swabs, respectively, from apparently healthy sheep. in a local abattoir, 205 lungs were investigated, 34% of which showed pneumonia, from which samples were collected from 51 ...200312625399
transport of l-[125i]thyroxine by in situ perfused ovine choroid plexus: inhibition by lead exposure.lead (pb) exposure hinders brain development in children by mechanisms that remain unknown. previous evidence shows that sequestration of pb in the choroid plexus lowers the production and secretion of transthyretin (ttr), a thyroxine (t4) transport protein, from the choroid plexus into the cerebrospinal fluid (csf). this study was undertaken to characterize the uptake kinetics of t4 by the choroid plexus and to determine if in vivo pb exposure altered the t4 uptake in an in situ perfused ovine ...200312712631
selenoenzyme activities in selenium- and iodine-deficient sheep.this study was conducted to evaluate the effects of single and combined deficiencies of selenium and iodine on selenoenzyme activities in sheep. twenty-four male lambs were assigned to one of four semisynthetic diets: combined deficient a (se-i), se-deficient b (se-i+), i-deficient c (se+i-), and basal diet d (se+i+). thyroid hormones (t3, t4), thyroid stimulating hormone (tsh), and inorganic iodine (pii) were determined in plasma. selenium and glutathione peroxidase activity (gsh-px) were deter ...200312972689
monthly changes in some reproductive parameters and in testosterone and thyroxine values of rams throughout one year under continental climate conditions.ten sexually mature rams were used in this study. blood and semen was collected monthly from rams for one period of 12 months to study semen characteristics and to determine serum testosterone and thyroxine (t4) hormones. results showed that all of the rams are continuous breeders as they show sexual desire and produce semen throughout the whole year. however, monthly variations in reproductive and semen characteristics were detected. relative testes volume, ejaculate volume, sperm motility, spe ...200314679837
iodine supplementation restores fertility of sheep exposed to iodine deficiency.the aims of the study were to monitor sheep iodine intake in different sheep breeding farms in abruzzo and to evaluate the effects of iodine supplementation on ovine fertility. the urinary iodine concentrations (uic) in animals of 8 out of the 11 breeding farms analyzed were borderline (uic 100-150 microg/l) or very low (uic < or = 50 microg/l). only animals bred in 3 farms showed an adequate iodine intake with a mean uic > or = 300 microg/l. animals with very low iodine intake had lower t4 and ...200315008245
effects of therapeutic and toxic doses of levamisole on thyroid hormones and some biochemical parameters in sheep.this study was carried out to establish the effects of therapeutic and toxic doses of levamisole on thyroid hormone levels and some biochemical parameters in sheep. twelve akkaraman ewes were used. levamisole was given orally at doses of 7.5 mg kg(-1) (group 1) and 40 mg kg(-1) (group 2) to the animals. blood samples were taken from the jugular vein at 2, 4, 8, 24, 48, 96 and 144 h after the administrations. serum thyroid hormones and some biochemical parameters were determined on these samples. ...200415338466
alterations of somatotropic function in prion disease in sheep.this study aimed at investigating the possible linkage between natural scrapie and alterations of the somatotropic axis. scrapie-affected ewes exhibited 2-fold higher mean gh concentrations during both autumn and spring. gh pulse frequencies were higher in scrapie-affected ewes than in control animals (mean+/-s.e.m. number of pulses/24 h: 10.4+/-0.9 and 7.6+/-0.9 for scrapie-affected and control ewes respectively) suggesting the involvement of central mechanisms. gh secretion induced by administ ...200415531730
a review of the "mysterious" wasting disease in swedish moose (alces alces l.) related to molybdenosis and disturbances in copper metabolism.the main purpose of this article is to review the previously published data on so-called "moose sickness" in the light of two case studies presented here. molybdenosis and mo-induced disturbances of cu metabolism in moose are characterized by numerous severe lesions caused by reduced activity of cu-containing enzymes such as ceruloplasmin, superoxide dismutase in blood, and myocardial cytochrome c oxidase. consequences of such metabolic disturbances (e.g. glucose intolerance, insulin resistance, ...200415621935
changes in blood levels of zinc, copper, selenium, glutathione peroxidase, vitamin b12 and total and free thyroxine in sheep removed from pasture and held without food for 50 hours.blood was collected from a group of ten sheep immediately after removal from pasture and thereafter at regular intervals for 50 hours whilst maintaining them without food but with adequate water. the samples were analysed for parameters normally examined as an aid to the diagnosis of zinc, copper, selenium, cobalt and iodine status. serum vitamin b12 levels increased with time. mean plasma zinc concentrations and mean serum concentrations of both t4 and ft4 followed significant parabolic trends. ...198616031208
an investigation of the possible effects of subclinical iodine deficiency on ewe fertility and perinatal lamb mortality.a controlled supplementation trial was performed in an assumed iodine-deficient romney ewe flock in the manawatu. significantly more twin litters were born to iodine-supplemented ewes than to control ewes. furthermore, the perinatal mortality rate in lambs born to iodine-supplemented dams was significantly lower than in lambs born to control dams. ewe age and the use of different lambing paddocks for iodine-supplemented and control ewes may have been confounding factors. in both iodine-supplemen ...199716031990
recent information on iodine deficiency in new zealand sheep flocks.to determine the value of pasture iodine, serum thyroxine (t4) and tri-iodothyronine (t3) concentrations and thyroid (g) to body weight (kg) ratios in lambs as criteria to predict and diagnose increased litter size and decreased perinatal mortality in response to iodine supplementation.199816032052
decrease of transthyretin synthesis at the blood-cerebrospinal fluid barrier of old sheep.transthyretin (ttr), synthesized by the choroid plexus (cp) and secreted into cerebrospinal fluid (csf), is involved in thyroxine (t4) transport and chelation of beta-amyloid peptide, attenuating neurotoxicity. to characterize age-related changes in ttr synthesis, csf and cps were collected from young adult (1-2 years) and old (>8 years) sheep anesthetized with thiopentone sodium. ttr in old sheep csf was low compared to young (n = 4 each); however, cp messenger rna (mrna) for ttr did not change ...200516079207
a comparison of the anti-luteolytic activities of recombinant ovine interferon-alpha and -tau in sheep.interferon tau (ifnt) is secreted by the trophectoderm of ruminant conceptuses during the peri-implantation period and serves an anti-luteolytic function. the question as to whether ifnt is superior as an anti-luteolytic agent to closely related type i ifns, such as ifn alpha (ifna), which have a different function, remains unanswered. thus, the aim of this study was to determine whether equivalent antiviral (av) units of ovifna and ovifnt are equipotent in extending estrous cycle length. four d ...200516079305
dose-dependent transthyretin inhibition of t4 uptake from cerebrospinal fluid in sheep.transthyretin (ttr), synthesized by the choroid plexuses (cp) has an important role in transporting thyroxine from blood to cerebrospinal fluid (csf). however, the role of ttr on thyroxine transport from csf to either blood or brain is not clear. by using the incubated isolated ovine brain tissues technique, we found the cp accumulated most 125i-t4 compared to ventricular ependymal, frontal cortex or cerebellum. the accumulation was higher in the young cp than the old. there was dose-dependent i ...200616325339
ontogeny and effects of thyroid hormone on beta1-adrenergic receptor mrna expression in ovine fetal kidney cortex.previous studies indicate that thyroidectomy (tx) decreases renin gene expression in ovine fetal renal cortex in late gestation. fetal ovine renin-containing renocortical cells become increasingly responsive to beta-adrenergic stimulation as gestation proceeds. increases in plasma thyroid hormone concentrations parallel this change, suggesting that there is a positive developmental relationship between the two. to examine this hypothesis, we determined the ontogeny of beta1-adrenergic receptor ( ...200516325745
fetal-to-maternal transfer of thyroid hormone metabolites in late gestation in sheep.3,3'-diiodothyronine sulfate (t2s) derived from t3 of fetal origin is transferred to the maternal circulation and contributes significantly to the maternal urinary pool. the present study quantitatively assesses the fetal to maternal transfer of t4 metabolites compared with those of t3. labeled t4 or t3 was infused intravenously to four singleton fetuses in utero in each group at gestational age 138 +/- 3 d. maternal and fetal serum and maternal urine samples were collected hourly for 4 h and at ...200616327008
effect of selenium supplementation on thyroid hormone levels and selenoenzyme activities in growing lambs.the aim of the present study was to evaluate the effects of selenium supplementation on thyroid hormone metabolism and selenoenzyme activities in lambs. twelve 20-d-old male lambs were assigned to one of two diets: a (0.11 ppm se) and b (supplemented with 0.2 ppm selenium as sodium selenite). blood samples were collected weekly for the determination of t3, t4, and selenium levels. the response to thyrotropin-releasing hormone (trh) challenge was estimated at the 11th and 20th wk. animals were sl ...200616444004
placental restriction alters circulating thyroid hormone in the young lamb postnatally.intrauterine growth restriction (iugr) is associated with accelerated growth and increased adiposity in early life due to unknown mechanisms, which could include increased thyroid hormone (th) action. we hypothesized that placental restriction (pr) of fetal growth would increase circulating th concentrations and alter their response to fasting, and that these would relate to growth and body composition in the young lamb. pr reduced size at birth, increased fractional growth rates (fgrs) of soft ...200616627695
endocrine characteristics of late pregnant hyperketonaemic ewes and their reproductive performance following the induction of ovarian cyclicity out of the breeding season.ketosis was diagnosed in a flock of merino ewes that conceived from synchronised oestrus in the early autumn period. on day 140 of pregnancy the ewes were sampled for determination of betaoh-butyrate (bhb), ast, glucose, non-esterified fatty acids (nefa), total cholesterol (tch), insulin, t4, t3, cortisol, igf-1 and leptin. the results were evaluated according to the number of fetuses born some days later and the presence of hyperketonaemia (bhb: > or = 1.60 mmol/l). in may, about 3 months after ...200616841761
serum thyroid hormones and performance of offspring in ewes receiving propylthiouracil with or without melatonin.two experiments were conducted during mid-gestation to examine effects in ewes of propylthiouracil (ptu) treatment alone or with melatonin on serum thyroid hormones, postpartum reproduction, and lamb performance. in the first experiment, beginning on day 0 (first day of treatment when all animals were 72.2+/-0.9 days of gestation), ewes received daily treatments (gavage) consisting of either 0mg (n=6) or 40 mg (n=6) ptu/kg body weight/day for 15 days. after 15 days, the 40 mg dosage was decrease ...200716895746
effects of seasonal and physiological variations on the serum chemistry, vitamins and thyroid hormone concentrations in sheep.the aim of this study was to investigate the possible effects of the reproductive status and seasonal variations on the serum chemistry and vitamin status and their relationships with the thyroid hormones in sakiz-awassi crossbreed sheep. the sheep (n = 34) were divided into two groups. the first group (n = 22) was mated; the second group (n = 12) was not mated. their serum samples were collected four times a year at the each season and under reproductive status. the periods are 1, early pregnan ...200616901267
developmental control of iodothyronine deiodinases by cortisol in the ovine fetus and placenta near term.preterm infants have low serum t4 and t3 levels, which may partly explain the immaturity of their tissues. deiodinase enzymes are important in determining the bioavailability of thyroid hormones: deiodinases d1 and d2 convert t4 to t3, whereas deiodinase d3 inactivates t3 and produces rt3 from t4. in human and ovine fetuses, plasma t3 rises near term in association with the prepartum cortisol surge. this study investigated the developmental effects of cortisol and t3 on tissue deiodinases and pl ...200616959839
thyroid hormone replacement normalizes renal renin and angiotensin receptor expression in thyroidectomized fetal sheep.previous studies have suggested that thyroid hormone influences maturation of the renin-angiotensin system (ras) and cardiovascular function in the late-gestation fetal sheep. to further examine the importance of thyroid hormone in this regard, we used the technique of thyroidectomy (tx) to remove endogenous thyroid hormone from the circulation and then replaced it with physiological amounts of exogenous thyroxine. we hypothesized that the previously observed changes in ras activity and cardiova ...200717567715
prevention of suckling improves postpartum reproductive responses to hormone treatments in pelibuey ewes.to determine the effects of suckling on postpartum (pp) reproductive efficiency in pelibuey ewes, two experiments were performed. in experiment 1, 112 ewes were randomly assigned to one of two groups at parturition: without restriction of suckling (wrs) 24 h day(-1) for 60 days (n=56), and weaned ewes (we), weaned at 40 days pp (n=56). on day 30 pp, all ewes were given prostaglandin (pgf2alpha) and one of four treatments (n=14): t1, intravaginal progestagen (fga; 40 mg) for 12 days from day 30 p ...200817669607
effect of supplementation of dietary protected lipids on intake and nutrient utilization in deccani lambs.four complete isonitrogenous (crude protein 13%) rations with 0 (t1), 5 (t2), 10 (t3) and 15 (t4) per cent calcium soap from red palm oil (protected fat) were formulated and evaluated using four deccani lambs (19.32 +/- 0.82 kg) in a completely randomized design at the end of a growth trial. the average daily dry matter intake (% body weight or g/kg w0.75 per day) in lambs fed ration t4 was significantly (p < 0.05) lower than in those fed rations t1, t2, and t3. there was no significant differen ...200617682600
effect of semen collection frequency on seasonal variation in sexual behaviour, testosterone, testicular size and semen characteristics of tropical hair rams (ovis aries).the purpose of this study was to examine the effect of day length on seminal characteristics, testicular size, sexual behaviour and testosterone (t4) concentration in pelibuey rams subjected to different semen collection frequencies. eighteen intact males were assigned randomly to one of two semen collection frequencies: in the high rate (hr) treatment, two ejaculations per week were obtained from each ram; one ejaculation every two weeks was collected under the low rate (lr) treatment. all anim ...200717847822
serum t3 and t4 concentrations in lambs with nutritional myodegeneration.selenium (se) deficiency is an important etiological factor in nutritional myodegeneration disease (nmd) of lambs, and se is required for synthesis of thyroid hormones.200717939578
effect of supplementing urea-treated barley straw with lucerne or vetch hays on feed intake, digestibility and growth of arsi bale sheep.the study was conducted at sinana agricultural research center, ethiopia to assess the supplementation of graded levels of vetch (vicia dasycarpa 'lana') and lucerne (medicago sativa,' hunter river') hay on feed intake, digestibility and body weight (bw) change of arsi-bale sheep fed urea treated barley straw (utbs). a 7 day- digestibility and a 90 day- feed intake trials were conducted using 28 and 35 sheep, respectively. the experimental design was a randomized complete block design with seven ...200918759063
feed intake, digestibility, body weight and carcass parameters of afar rams fed tef (eragrostis tef) straw supplemented with graded levels of concentrate mix.the experiment was conducted at alamata agricultural research center, ethiopia using 20 afar rams with an initial body weight (bw) of 18.2 +/- 1.76 (mean +/- sd) kg. the objectives were to study the effect of supplementation with concentrate mix consisting of wheat bran (wb), noug seed cake (nsc) and sesame seed cake (ssc) at the ratio of 2:1:1 on dry matter (dm) basis, respectively on feed intake, digestibility, bw gain and carcass parameters of afar rams fed tef (eragrostis tef) straw basal di ...200918777140
effects of supplementation of farta sheep fed hay with sole or mixtures of noug seed meal and wheat bran on feed intake, digestibility and body weight change.digestibility and feeding trials for 10 and 90 days were conducted using 25 yearling farta rams with a mean body weight (bw) of 16.8 +/- 0.17 kg (mean +/- sd) to study the effects of supplementation with sole or mixtures of noug seed meal (nsm) and wheat bran (wb) on feed intake, digestibility and bw change in farta sheep fed hay. the experimental design was a randomized complete block design. the sheep were arranged in five blocks based on initial bw, and the five treatments were assigned rando ...200818975124
assessing the efficacy of duddingtonia flagrans chlamydospores per gram of faeces to control haemonchus contortus larvae.the aims were (a) to quantify the number of duddingtonia flagrans chlamydospores per gram of faeces (cpg) recovered from sheep administered with different oral doses and, (b) to describe the relationship between cpg and eggs per gram of faeces (epg) on the efficacy to reduce haemonchus contortus infective larvae. three doses of chlamydospores per kg bw were orally administered during seven days: (t1) non treated control group, (t2) 1 x 10(6), (t3) 2.5 x 10(6) and (t4) 5 x 10(6). three lambs, inf ...200819028012
perilesional changes of focal osteochondral defects in an ovine model and their relevance to human osteochondral injuries.perilesional changes of chronic focal osteochondral defects were assessed in the knees of 23 sheep. an osteochondral defect was created in the main load-bearing region of the medial condyle of the knees in a controlled, standardised manner. the perilesional cartilage was evaluated macroscopically and biopsies were taken at the time of production of the defect (t0), during a second operation one month later (t1), and after killing animals at three (t3; n = 8), four (t4; n = 8), and seven (t7; n = ...200919651847
feeding value and in vitro digestibility of date-palm leaves supplemented with different supplementary energy.the aim of this study was to evaluate the feeding value and also the effect of different supplementary energy on increasing in vitro dm digestibility of date-palms leaves obtained in pruning. a randomized complete design with different energy supplementary with 3 replicates was conducted. harvested date-palm leaves were air-dried, ground through a 5 mm screen, then palm leaves (l) ensiled with different levels of urea (u) and other supplementary energy. combination, mixture was packed tightly in ...200919806815
feed intake, digestibility, nitrogen utilization, and body weight change of sheep consuming wheat straw supplemented with local agricultural and agro-industrial by-products.effects of supplementing sheep consuming wheat straw with local agro-industrial by-products on feed intake, growth, digestibility and nitrogen utilization were determined. thirty 1-year-old local wethers, with a mean (+/-sd) live weight of 19.8 (+/-1.06) kg, were assigned to five treatments: wheat straw + atella (t1), wheat straw + atella + poultry litter (t2), wheat straw + atella + coffee pulp (t3), wheat straw + atella + coffee pulp + poultry litter (t4), hay + concentrate (t5). a 7-day diges ...201019882225
effect of supplementation of simada sheep with graded levels of concentrate meal on feed intake, digestibility and body-weight parameters.the experiment consisting of 7 days of digestibility and 90 days of feeding trial was conducted at wogda (ethiopia) to determine the effect of supplementation of graded levels of concentrate mix (cm) on feed intake, digestibility, and body weight (bw) change in hay-based feeding of simada sheep. twenty-yearling simada sheep with a mean initial bw of 17.9 +/- 0.81 kg (mean +/- sd) were used in randomized complete block design arranged into five blocks of four animals. the four dietary treatments ...201019898949
is the mechanisms of fipronil-induced thyroid disruption specific of the rat: re-evaluation of fipronil thyroid toxicity in sheep?in rat, fipronil treatment increases the elimination of thyroid hormones (th). relevance of this mechanism for the risk of fipronil for human health is subject to controversy because of the specificities of adult rat for th plasma binding properties which often lead to the assumption that rats are more sensitive than human to thyroid disruption. this study aimed at determining if the mechanism of fipronil-induced thyroid disruption is altered in sheep a species more relevant to human from the st ...201020117195
cytotoxic proteins of amanita virosa secr. mushroom: purification, characteristics and action towards mammalian cells.a new hemolytic lectin was purified from the fruit bodies of amanita virosa secr. mushroom by the affinity chromatography on the cross-linked ovomucin. this lectin destroyed erythrocytes of human and animals of various species, and its hemolytic activity decreased in the row: rabbit > rat > human > dog. the erythrocytes of sheep, cow and carp were resistant to such hemolytic action of the lectin (1 mg/ml). the lectin-mediated hemolysis was blocked by the polyethylene glycol with molecular mass o ...201020153765
independent changes of thyroid hormones in blood plasma and cerebrospinal fluid after melatonin treatment in ewes.the authors measured the effects of exogenous melatonin treatment on the concentrations of total (t) and free (f) fractions of thyroxine (t4) and triiodothyronine (t3) in cerebrospinal fluid (csf) and blood plasma as well as the expression of their binding/transporter protein, transthyretin (ttr), in the choroid plexus of ewes from may to august. melatonin implantation in may and july mainly prevented the decrease in plasma for ft3 and tt3 exhibited in untreated group, and induced a limited decr ...201020452012
supplementation of farta sheep fed hay with graded levels of concentrate mix consisting of noug seed meal and rice bran.the study was carried out at woreta, ethiopia, to determine feed intake, digestibility, body weight (bw) change, and profitability of farta sheep fed pasture hay alone or supplemented with graded levels of concentrate mix (cm) consisting of noug seed meal (nsm) and rice bran in 2:1 ratio. twenty yearling intact male farta sheep with bw of 16.9 +/- 1.68 kg (mean +/- sd) were used in randomized complete block design arranged into five blocks of four animals. the dietary treatments consisting of so ...201020490664
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