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1.
AbstractAIMS: To measure the magnitude and variability in production responses to anthelmintic treatments administered to adult ewes around lambing.METHODS: Ewes carrying twin lambs, from sheep and beef farms (eight in Year 1 and six in Year 2) in the Wairarapa region of New Zealand, were enrolled in 14 trials (part of an experiment carried out on one farm in one year). Experiment 1 compared ewes treated 2–4?weeks pre-lambing with a controlled release capsule (CRC) containing abamectin, albendazole, Se and Co, to ewes injected pre-lambing with a long-acting Se plus vitamin B12 product, and to untreated ewes. Experiment 2 included these treatments, plus a CRC administered at pregnancy scanning. Experiment 3 included the same treatments as Experiment 1, plus administration of a CRC containing albendazole, Se and Co, injectable moxidectin or oral derquantel plus abamectin, all administered pre-lambing, or oral derquantel plus abamectin administered 4–6?weeks after lambing. Variables compared were ewe liveweight at weaning and pre-mating, lamb liveweight at weaning, total weight of lamb weaned per ewe and ewe dag score at weaning.RESULTS: Ewes treated with a CRC pre-lambing were heavier than untreated ewes (mean 3.2?kg) at weaning in 12/14 trials, and pre-mating (mean 2.8?kg) in 9/14 trials (p<0.001). Compared with mineral-treated ewes the mean difference was 2.8?kg pre-lambing (9/14 trials) and 1.7?kg pre-weaning (6/14 trials). Lambs reared by treated ewes were heavier (mean 1.55?kg) at weaning in 6/14 trials (p<0.001), but there was no effect of CRC treatment on total weight of lambs weaned per ewe (p=0.507). Variation in weight of lamb weaned per ewe was largely explained by differences in lamb survival from birth to weaning (p<0.001), with no effect of CRC treatment (p>0.65).Treatment of ewes with a CRC at pregnancy scanning was neither better nor worse than a pre-lambing treatment (p=0.065).There was no difference in the response from treatment with either of the two CRC or moxidectin. Treatment with short-acting oral anthelmintics resulted in no consistent benefit.CONCLUSIONS: Anthelmintic treatments administered to ewes around lambing resulted in variable responses between farms and years, which in some trials were negative for some variables, and some of the variability was due to the mineral component of the CRC. The widespread perception amongst farmers and veterinarians that anthelmintic treatment of ewes around lambing will always result in positive benefits is not supported. 相似文献
2.
A trial was carried out to determine whether selenium responsive unthriftiness existed on a property in the Strathbogie ranges of Central Victoria where unthriftiness of young sheep has been a problem for 10 to 20 years. White muscle disease had been diagnosed on the property in the previous year and on other properties in the area. Eighty Merino ewes and lambs were allotted to one of 4 groups in a 2 x 2 factorial designed trial in which sodium selenite (0.1 mg/kg) was given orally to ewes and/or lambs at marking time and to treated lambs at 3 monthly intervals thereafter. Selenium treatment of the ewes had no significant effect on subsequent lamb performance. Selenium treatment of the lambs produced significant responses: mortality in treated groups was 0% compared with 17.5% in untreated groups; body weight gains were 1.9 kg higher at both weaning and one year of age in treated than in untreated lambs; mean fleece weight was 14.4% higher in treated lambs and they produced 39% more wool than the surviving untreated lambs. 相似文献
3.
Avilés-Nova F Espinoza-Ortega A Castelán-Ortega OA Arriaga-Jordán CM 《Tropical animal health and production》2008,40(7):509-515
Liveweight gain was evaluated in tropical Dorper X Pelibuey lambs under intensive continuous grazing of native grasslands dominated by Paspalum notatum (PN) or Axonopus compressus (AC) in the subtropics of Central Mexico. Two trials were undertaken. Trial 1 lasted 12 weeks with 10 lambs (initial weight 18 +/- 2.57 kg, 3 months old) per treatment in 2002, and Trial 2 for 13 weeks with 8 lambs (initial weight 24.0 +/- 2.0 kg, 4 months old) per treatment. Lambs were weighed once per week, and liveweight change was estimated by linear regression over day of the experiment, using individual regression coefficients as unbiased estimates of daily liveweight change; analysed in a random block design. Lambs on Trial 1 gained 0.061 kg/lamb/day on PN and 0.047 kg/lamb/day on AC (P > 0.05) at an overall mean stocking rate of 25 lambs/ha. In Trial 2, liveweight gain was significantly larger in PN (0.060 kg/lamb/day) than on AC (0.043 kg/lamb/day) (P < 0.05), at a mean stocking rate of 21.5 lambs/ha. It is concluded that intensive continuous grazing of native grasslands in the subtropics of the highlands of Central Mexico enables moderate liveweight gains for weaned lambs during the rainy season; with better results in grasslands dominated by Paspalum notatum. 相似文献
4.
The effects of Damalinia bovis and Linognathus vituli infestations on the liveweight gains and haematocrit levels of cattle were evaluated in eight controlled trials involving a variety of cattle breeds and age-groups ranging from 2 to 20 months. There were no statistically significant differences in weight gain or haematocrit levels between louse-infected and louse-free groups in any trial. The difference between these results and those obtained by North American workers could be due to the fact that Haematopinus eurysternus, one of the predominant louse species in North America, was not present in any of the trials. It is concluded that under most conditions New Zealand farmers are unlikely to benefit financially from increased weight gains following treatment of cattle for lice. 相似文献
5.
Background
Selenium is part of the antioxidant defence system in animals and humans. The available selenium concentration in soil is low in many regions of the world. The purpose of this study was to evaluate the effect of organic versus inorganic selenium supplementation on selenium status of ewes, their lambs, and slaughter lambs.Methods
Ewes on four organic farms were allocated five or six to 18 pens. The ewes were given either 20 mg/kg inorganic selenium as sodium selenite or organic selenium as selenized nonviable yeast supplementation for the two last months of pregnancy. Stipulated selenium concentrations in the rations were below 0.40 mg/kg dry matter. In addition 20 male lambs were given supplements from November until they were slaughtered in March. Silage, hay, concentrates, and individual ewe blood samples were taken before and after the mineral supplementation period, and blood samples were taken from the newborn lambs. Blood samples from ewes and lambs in the same pens were pooled. Muscle samples were taken from slaughter lambs in March. Selenium concentrations were determined by atomic absorption spectrometry with a hydride generator system. In the ANOVA model, selenium concentration was the continuous response variable, and selenium source and farm were the nominal effect variables. Two-sample t-test was used to compare selenium concentrations in muscle samples from the slaughtered lambs that received either organic or inorganic selenium supplements.Results
In all ewe pens the whole blood selenium concentrations increased during the experimental period. In addition, ewe pens that received organic selenium had significantly higher whole blood selenium concentrations (mean 0.28 μg/g) than ewe pens that received inorganic selenium (mean 0.24 μg/g). Most prominent, however, was the difference in their lambs; whole blood mean selenium concentration in lambs from mothers that received organic selenium (mean 0.27 μg/g) was 30% higher than in lambs from mothers that received inorganic selenium (mean 0.21 μg/g). Slaughter lambs that received organic selenium had 50% higher meat selenium concentrations (mean 0.12 mg/kg wet weight) than lambs that received inorganic selenium (mean 0.08 mg/kg wet weight).Conclusion
Organic selenium supplementation gave higher selenium concentration in ewe and newborn lamb blood and slaughter lamb meat than inorganic selenium supplementation. 相似文献6.
本文对中药在羔羊育肥中的应用进行了系统性的探讨。通过对相关文献的梳理和分析,总结了中药在提高羔羊体重、促进肌肉生长、改善免疫力等方面的作用与机制,并探讨了中药与硒、锌等微量元素的联合应用对羔羊育肥的协同作用。不仅为提高羔羊养殖效益提供了新思路和方法,也有助于推广中药在畜牧业中的应用。 相似文献
7.
Vaccination: Is it Effective in Preventing Respiratory Disease or Influencing Weight Gains in Feedlot Calves? 总被引：14，自引：7，他引：7
Respiratory disease, both undifferentiated and etiologically defined, remains a major problem in feedlot cattle. Vaccination has been used in an attempt to reduce the frequency and/or severity of respiratory disease in the first few weeks after the cattle arrive at the feedlot.
The efficacy of vaccination has been studied both in controlled laboratory experiments and field trials as well as observational studies. (In this review, efficacy refers to the ability to reduce overall treatment rate and/or increase weight gains.) This review summarizes the data resulting from studies of vaccine efficacy.
In general, there is little published data to support the use of vaccines against respiratory disease under feedlot conditions. Treatment rates and weight gains usually did not differ between vaccinated and nonvaccinated groups. The use of live bovine virus diarrhea virus vaccines was associated with a significant subsequent increase in treatment rates. Criteria to be considered in future field trials are described.
相似文献8.
不同放牧率对混播草地牧草与羔羊生产的影响 总被引：2，自引：0，他引：2
通过三种放牧率对混播草地牧草和羔羊生产的影响进行了研究。结果表明，随着放牧率的增加，牧草产量、叶面积指数明显下降（Ｐ＜０．０５）并使茎叶比显著减少（Ｐ＜０．０５）。放牧率的增大，羔羊个体生产速度显著降低（Ｐ＜０．０１），单位面积的畜产品产量依次为中组＞低组＞高组。并得出羔羊生长量与放牧强度及采食牧草干物质量存在密切关系，同时放牧率影响肉的品质，放牧率不同，草地系统生物学转化效率中组比低、高组高，且草地生产能力最大。由此得出，混播草地以中等放牧率为最佳。 相似文献
9.
Two trials were undertaken with lambs grazing selenium deficient pasture to determine if copper would enhance liveweight and fleece-weight responses to selenium supplementation. In the first trial, lambs given selenium or selenium plus copper gained significantly more weight and had higher fleece-weights after 260 days than did control lambs or lambs given copper alone. Copper given alone or together with selenium had no significant effect on liveweight or fleece-weight when compared with control lambs and lambs that were given selenium alone respectively. This finding was confirmed in a second trial when growth and fleece-weights of selenium and selenium plus copper treated lambs were compared and no significant differences found. In both trials copper significantly raised liver copper levels. In selenium supplemented but not in selenium deficient sheep, copper significantly increased blood selenium levels. 相似文献
10.
CB Garland 《New Zealand veterinary journal》2013,61(4):220-226
AbstractAIM: To conduct a cost-benefit analysis of the administration of anthelmintics to adult ewes around lambing.METHODS: Production data from comparisons of different anthelmintic treatments with no treatment were used in a cost-benefit analysis. The data were from 14 trials (part of an experiment carried out on one farm in 1 year) conducted on sheep and beef farms (eight in 2011 and six in 2012) in the Wairarapa region of New Zealand. The cost structure involved the purchase price of products and the labour cost of administration. The four key benefits identified for the calculation of economic returns, relative to untreated ewes, were: increased value of ewes sold (culled) at weaning, additional lambs weaned related to ewe liveweight at mating, increased total weight of lamb weaned per ewe, and reduced number of ewes requiring removal of soiled wool at weaning due to a lower dag score. Commercial values for these variables as at December 2013 were used, with the measured production data, to calculate a net (NZ$) benefit for every treatment-trial combination.RESULTS: The economic return on treating ewes around lambing with anthelmintics was highly variable and across all trials treatment resulted in a financial loss in 18/38 (47%) groups of ewes. The mean net benefit from pre-lambing administration of a controlled release capsule (CRC) containing albendazole and abamectin was 5.36 (95% CI=?2.64 to 13.35) $/ewe, but overall was not different from zero (p=0.171). A breakdown of the overall gross benefit into its various components showed that weight of lamb weaned per ewe had the largest influence (a mean benefit of $5.68/ewe), followed by ewe liveweight pre-mating ($2.45/ewe), ewe liveweight at weaning ($0.66/ewe) and reduced dag score ($0.15/ewe). Other anthelmintic treatments all showed highly variable responses amongst trials, with some negative cost-benefits. There was no significant difference between any of the treatments except a short-acting oral treatment at tail-docking had a lower net benefit than a CRC containing albendazole administered pre-lambing (p<0.05).CONCLUSIONS: A positive financial return resulting from the anthelmintic treatment of adult ewes around lambing is neither consistent nor predictable, and is often not achieved. Given that the additional costs of accelerating the development of anthelmintic resistance were not included in these calculations, farmers need to consider carefully the merits of administering anthelmintics to ewes around lambing. 相似文献
11.
Talal Al Khewani Mohamed Momani Shaker Samer Al-Olofi 《Tropical animal health and production》2014,46(8):1363-1370
A fattening experiment was carried out to analyze and evaluate the effect of ram lamb genotype on the growth, feed conversion (FC), and carcass value of Dhamari ram lambs, F1 crossbreds of Dhamari?×?Tehami (F1 DhT), and Tehami ram lambs. Genotype of the ram lambs including the experiment (n?=?30) had high significant effect on total weight gain (TWG), average daily gain (ADG), and FC (P?P?P?P?P?P?P?1 DhT was better than Tehami ram lambs in ADG, TWG, and FC. Additionally, the results show that the feed conversion was in F1 DhT crossbreds ram lambs better than pure Dhamari and Tehami ram lambs, mainly in the carcass indicators. 相似文献
12.
Abstract Two selenium (Se) supplementation trials were conducted in successive years involving a total of 70 red deer calves 3–15 months of age grazing pasture containing 30–57 ppb of Se on a dry matter basis. The trials compared growth rate, whole blood Se and glutathione peroxidase (GSHpx) concentrations of calves which received periodic doses of oral Se or a single injection of barium selenate (equivalent to 50 mg Se) or no Se supplementation. There were no significant weight gain differences between treated and untreated groups in either trial. Whole blood GSHpx levels were strongly correlated with blood Se levels (r = 0.9278) and produced the following regression equation: GSHpx 0.0155 Se ? 2.292. In both years the 3 month old calves had GSHpx levels of 6–9 kU/l which probably derived from maternal transfer of Se. The GSHpx levels in unsupplemented calves declined from these levels to a minimum in winter (group means ? 2.6) and then progressively rose the following spring and summer. Periodical oral dosing with Se or a single injection of barium selenate significantly elevated blood Se and GSHpx levels throughout the trials. 相似文献
13.
EFFECT OF SELENIUM ON WOOL PRODUCTION, BODY WEIGHT AND MORTALITY OF YOUNG SHEEP IN WESTERN AUSTRALIA 总被引：1，自引：0，他引：1
The effect of regular selenium supplementation on the body weight, wool production and mortality of young Merino sheep was investigated. Groups of Se-treated and control sheep involving from 260–500 on each of 15 farms were observed from six weeks to 19 months of age. Ten mg Se as sodium hydrogen selenite was administered orally to the treated sheep at two-monthly intervals. Treated and control sheep grazed together throughout the trial period. Statistically significant responses to selenium were recorded in body weight gains on four farms, in decreased mortality on five farms and as an increase in fleece weight on eight farms. The response in fleece weight varied from 2.9-7.6% and could not be explained as a result of increased body weight. The increase in fleece weight was not due to an increase of grease in the wool but appeared to be due to an increase in fibre diameter and to a lesser extent an increase in staple length. A statistically significant decrease in the incidence of tender fleeces as a result of selenium supplementation was also recorded. All farms on which responses to selenium were obtained were in areas with average annual rainfall more than 20 inches. On two farms selenium caused statistically significant depressions in the parameters measured. Both farms were in areas with less than 20 inches average annual rainfall. 相似文献
14.
Selenium supplementation affects broiler growth performance, meat yield and feather coverage 总被引：1，自引：0，他引：1
(1) Selenium (Se) is an essential part of numerous selenoproteins, most of which are involved in the antioxidant system of the body. It is also required by poultry for the maintenance of optimal health and meat quality. This paper reports data from a study examining the effect of dietary source and concentration of selenium on broiler performance and meat quality. (2) Increased dietary selenium content markedly reduced feed conversion ratio (FCR) as a result of significantly lower feed intakes of birds while maintaining the same weight gains. (3) Selenium supplementation increased feathering, with organic selenium (selenised yeast) being superior to inorganic selenium (sodium selenite). (4) Birds receiving organic selenium in their diets had improved eviscerated weight, breast yield and reduced drip loss. (5) There were significant concentration x source interactions on yields of breasts and marylands (thigh plus drumstick), with elevated levels of organic selenium increasing the yields, whereas the opposite was true for the inorganic selenium. 相似文献
15.
冬季羔羊舍饲育肥中应用膨润土的试验研究 总被引：3，自引：0，他引：3
在玉米秸为主的日粮中每头添加膨润土１６ｇ／ｄ和羟甲基尿素２０ｇ／ｄ进行羔羊快速育肥试验。结果表明,羔羊日增重由对照组的６５．００ｇ提高到试验组的１２０．６３ｇ,二者差异显著（Ｐ＜０．０５）。饲料转化效率提高４６．０１％。４０ｄ后羔羊瘤胃液ｐＨ值明显降低。膨润土能改善羔羊瘤胃消化代谢并促进羔羊生长。 相似文献
16.
H.G. Rees D.V.M. M.R.C.V.S. N.D.A. D.P. Boshier M.Sc Ph.D. 《New Zealand veterinary journal》2013,61(1-2):20-23
Equivalent doses of sodium selenate and sodium selenite were equally effective in preventing selenium deficiency in ewes on a diet containing a very low level of selenium. There was a wide variation between animals in blood-level response to a single dose of selenium, and in the time for which it would satisfy ewe requirement. When ewes were fed a hay ration containing a very low level of selenium, a single dose equivalent to 5 mg selenium would give protection for at least 6 months when injected subcutaneously compared with 4 months when administered orally. There was no significant difference in the response to subcutaneous injection of sodium selenate solution with needles of different sizes. There was no difference in effect between administration of 1 ml into the sheep's mouth or of 10 ml of a 1 in 10 dilution directly down the animal's throat. 相似文献
17.
G. Steinheim L. S. Eikje G. Klemetsdal T. Ådn⊘y 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(1):45-50
Abstract This study describes how birth weight, gender, litter size, and age of dam affect lamb mortality during the summer period, using data on lambs of the breeds Spælsau (N ≈ 110 000) and Norwegian White Sheep (N ≈ 450 000) during 1994 to 2005. A general mixed linear model was used for the analysis. Birth weight affected summer mortality non-proportionally: an increase in weight from very small towards the breed mean strongly deflated mortality risk; weigh increase above breed means had little effect. Male lambs had a higher mortality than females, and lambs born by 12-months-old dams were in greater risk than those having older dams. Increasing litter size resulted in increased mortality. The results are discussed and recommendations for future research, with focus on breeding and genotype by environment interaction effects are made. 相似文献
18.
Guinea pigs and swine were exposed to sulphur dioxide concentrations varying from 5-40 P.P.M.
The average daily weight gains of young guinea pigs were impaired by gas concentrations of 10 P.P.M. and 18 P.P.M. for periods of 96 hours or more. A single experiment failed to indicate any synergism between sulphur dioxide and hydrogen sulphide. Studies on the effect of exposure to 5 P.P.M. for an extended period were inconclusive.
Young swine under seven days of age were exposed to sulphur dioxide concentrations of 5, 10, 20, and 40 P.P.M. for a single eight-hour period for each group. All concentrations caused the animals to display some evidence of irritation from the gas, ranging from eye irritation, nasal secretion, salivation and altered respirations at levels of 10 P.P.M. and higher to slight eye irritation and salivation at levels of 5 P.P.M. Haemorrhage and emphysema were present in the lungs of swine exposed to 40 P.P.M., and sacrificed at twenty-four hours and seven days post-exposure. At 158 days post-exposure, two of two swine exposed to 40 P.P.M., and one of two swine exposed to 20 P.P.M. showed a pulmonary fibrosis that was attributed to the gas.
Impaired weight gains of exposed animals raised to market weight (158 days) could not be attributed to the gas.
相似文献19.
B. O. Fagbemi 《The Veterinary quarterly》2013,33(2):92-95
Summary A study of Ctenocephalides fells strongylus and of its effect on the performance of sheep and goats was made. Fleas showed more affinity for sheep than goats. There was a high concentration between lamb and kid mortality and the degree of flea infestation. The clinical effects of flea infestation are highlighted. The factors responsible for flea infestation and its control are discussed. 相似文献
20.
A preliminary study revealed significantly lower serum iron concentrations in lambs that developed abomasal bloat about one week later, than in lambs that did not develop bloat. In a subsequent trial, with 754 naturally reared twin lambs from five flocks, iron dextran injections were found to have a preventive effect on the development of abomasal bloat. Clinical signs of abomasal bloat were observed in the placebo-treated lamb of 16 couples and in the iron-treated lamb of six couples (P<0.05). In three further couples, both lambs developed bloat. The iron-treated group had significantly (P<0.001) better average weight gains, both from birth to summer, and from birth to autumn of approximately 0.5 and 1 kg, respectively. There was a reduction in red blood cell values and iron saturation in the placebo group 14 days after treatment but not in the iron-treated lambs. In one of the flocks, there was a decrease in the cumulative incidence of abomasal bloat from 37 per cent to 3 per cent during the period of four years after measures such as later lambing, earlier turnout and iron injections were introduced. 相似文献