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171.
172.
Strategic use of crutching and dicyclanil to protect unmulesed sheep against breech strike 总被引:1,自引:1,他引:0
Objective To test strategies for the application of dicyclanil and mid-season crutching to maximise protection of unmulesed sheep against breech strike.
Procedure Three hundred and eighty unmulesed Merino weaners were randomly allocated to four groups either left untreated or treated by different strategies with 50 g/L dicyclanil. Treatments included breech treatment alone and breech plus body treatment, with two application times, immediately after shearing and 6 weeks after crutching or shearing. To assess protection, larval implants with newly hatched Lucilia cuprina larvae were applied to 10 different sheep from each group at 3, 4, 5 and 6 months after crutching and shearing and assessed for the development of strike at 48 hours. The concentration of dicyclanil was measured in wool samples clipped from the breeches of the test sheep.
Results All dicyclanil treatments gave significant reduction in strike in comparison to controls up until 4 months after crutching but protection in the sheep treated immediately after shearing had waned at 5 months. Treating at 6 weeks after crutching provided significant reduction ( P < 0.05) in strike for 6 months. Results for strike incidence immediately after shearing and concentration of dicyclanil in the breech wool also suggested improvements in protection by delaying treatment for 6 weeks.
Conclusion In most environments it should be possible to protect unmulesed sheep against breech strike with a carefully planned integrated control program incorporating strategically timed crutching, shearing and dicyclanil application. Delaying treatment with dicyclanil to at least 6 weeks after shearing or crutching increased the protection provided in comparison to treatment immediately after shearing. 相似文献
Procedure Three hundred and eighty unmulesed Merino weaners were randomly allocated to four groups either left untreated or treated by different strategies with 50 g/L dicyclanil. Treatments included breech treatment alone and breech plus body treatment, with two application times, immediately after shearing and 6 weeks after crutching or shearing. To assess protection, larval implants with newly hatched Lucilia cuprina larvae were applied to 10 different sheep from each group at 3, 4, 5 and 6 months after crutching and shearing and assessed for the development of strike at 48 hours. The concentration of dicyclanil was measured in wool samples clipped from the breeches of the test sheep.
Results All dicyclanil treatments gave significant reduction in strike in comparison to controls up until 4 months after crutching but protection in the sheep treated immediately after shearing had waned at 5 months. Treating at 6 weeks after crutching provided significant reduction ( P < 0.05) in strike for 6 months. Results for strike incidence immediately after shearing and concentration of dicyclanil in the breech wool also suggested improvements in protection by delaying treatment for 6 weeks.
Conclusion In most environments it should be possible to protect unmulesed sheep against breech strike with a carefully planned integrated control program incorporating strategically timed crutching, shearing and dicyclanil application. Delaying treatment with dicyclanil to at least 6 weeks after shearing or crutching increased the protection provided in comparison to treatment immediately after shearing. 相似文献
173.
JLMR Leroy RG Sturmey V Van Hoeck J De Bie PJ McKeegan PEJ Bols 《Reproduction in domestic animals》2014,49(3):353-361
In many countries, fat supplementation in the diet has become common in the dairy industry. There are several ideas as to how dietary fat could influence reproductive performance. Saturated fatty acids, such as palm oil, can increase milk yield but may aggravate negative energy balance and thus may impair fertility when fed during the first week post‐partum. However, priming the lipid oxidation in the liver by feeding saturated fats during the dry period has recently been shown to be a potentially promising strategy to mitigate fat mobilization and liver accumulation post‐partum. Furthermore, polyunsaturated fats (omega‐3 fatty acids and conjugated linoleic acids) are fed to reduce the ‘de novo’ fat synthesis in the udder and thus the milk fat content, which may be of modest benefit for overall energy balance. Furthermore, omega‐6 and omega‐3 polyunsaturated fatty acids are reported to alter follicular growth, steroid synthesis and prostaglandin metabolism in the ovary and endometrium, respectively. Omega‐6 fatty acids are believed to have pro‐inflammatory and thus PGF2α‐stimulating properties rendering them extra value as ‘nutraceutical’ early post‐partum, while omega‐3 fatty acids can weaken this inflammatory potency, leading to a higher chance of survival of the embryo when supplemented during the periconceptual period. Unfortunately, research results rarely provide a consensus in this perspective. The consequences of these fat‐feeding strategies on oocyte and embryo quality remain an intriguing issue for debate. Fat feeding may alter the microenvironment of the growing and maturing oocyte of the early and older embryo and thus may affect reproductive outcome. We recently reported that dietary‐induced hyperlipidaemic conditions can be harmful for embryo development and metabolism. However, to date, research results remain somewhat conflicting most probably due to differences in fat sources used, in diet and duration of supplementation and in experimental set‐up in general. 相似文献
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GF Mackereth KM Webb JS O'Keefe PJ Duignan R Kittelberger 《New Zealand veterinary journal》2013,61(6):428-432
AIM: To conduct a longitudinal serological survey for evidence of Brucella spp and Leptospira spp infection of pre-weaned New Zealand fur seals in a colony on the Otago Peninsula. METHODS: Seal pups were repeatedly captured on a monthly basis from February through to July 2001. Pups were tagged at first capture and a blood sample was taken at each capture event. A total of 163 sera were collected from 118 seal pups. Where sufficient volume was collected, the sera were tested for leptospirosis using the microscopic agglutination test (MAT), and for brucellosis using the competitive enzyme-linked immunosorbent assay (ELISA) for Brucella abortus. RESULTS: None of 128 sera from 101 seals tested positive to the ELISA for B. abortus. All tests for Leptospira interrogans serovars Grippotyphosa, Copenhageni, Bratislava and Leptospira borgpetersenii serovar Ballum were negative at a cut-off of <1/100 dilution. Positive or suspicious titres were found to L. interrogans serovars Canicola and Pomona and L. borgpetersenii serovar Hardjo. The highest titres (12,800) were found to serovar Pomona. The titre to serovar Pomona in one seal rose from <1/50 in March to 12,800 in April and was <1/50 when re-sampled in July. The titre to serovar Pomona in another seal dropped from 12,800 in May to <1/50 in June. These seals also had titres to serovar Hardjo, which rose or fell in the same manner. All suspicious or positive titres occurred in late April and early May, when the pups were approximately 4–5 months old. In June and July, all seals tested were negative. CONCLUSIONS: There was no serological evidence of Brucella infection in the pre-weaned fur seals at the colony. Positive titres to serovars Pomona, Hardjo, or Canicola suggest that a Leptospira species was present at the colony, however isolation or visualisation of the organism is required to confirm this. Care should be exercised when handling New Zealand fur seals to prevent human infection or inadvertent transfer of leptospirosis to another marine mammal species. 相似文献
178.
Bovine citrullinaemia traced to the sire of Linmack Kriss King 总被引:1,自引:0,他引:1
PJ HEALY JA DENNIS LM CAMILLERI JL ROBINSON AL STELL RD SHANKS 《Australian veterinary journal》1991,68(4):155-155
179.
The efficacy of mixtures of albendazole sulphoxide and levamisole against sheep nematodes resistant to benzimidazole and levamisole 总被引:1,自引:0,他引:1
Faecal egg count reduction tests and an anthelmintic efficiency assay were used to assess the efficacy of combinations of albendazole sulphoxide and levamisole against populations of Ostertagia and Trichostrongylus sp. which contained different proportions of worms resistant to both benzimidazole and levamisole anthelmintics. Compared to the effects of either drug alone, significantly greater efficacy was obtained using combinations which included dose rates similar to those recommended for the separate components. At these dose rates, the mixtures reduced mean faecal egg counts by 95% or more, and caused a reduction of 68% in adult Ostertagia sp. and more than 95% for 4th stage Ostertagia and T colubriformis. The increased efficacy of the mixtures could be accounted for by actions of the drugs acting independently. 相似文献
180.
Antimicrobial drug use in veterinary medicine 总被引:1,自引:0,他引:1
Morley PS Apley MD Besser TE Burney DP Fedorka-Cray PJ Papich MG Traub-Dargatz JL Weese JS;American College of Veterinary Internal Medicine 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(4):617-629
Recognizing the importance of antimicrobial resistance and the need for veterinarians to aid in efforts for maintaining the usefulness of antimicrobial drugs in animals and humans, the Board of Regents of the American College of Veterinary Internal Medicine charged a special committee with responsibility for drafting this position statement regarding antimicrobial drug use in veterinary medicine. The Committee believes that veterinarians are obligated to balance the well-being of animals under their care with the protection of other animals and public health. Therefore, if an animal's medical condition can be reasonably expected to improve as a result of treatment with antimicrobial drugs, and the animal is under a veterinarian's care with an appropriate veterinarian-client-patient relationship, veterinarians have an obligation to offer antimicrobial treatment as a therapeutic option. Veterinarians also have an obligation to actively promote disease prevention efforts, to treat as conservatively as possible, and to explain the potential consequences associated with antimicrobial treatment to animal owners and managers, including the possibility of promoting selection of resistant bacteria. However, the consequences of losing usefulness of an antimicrobial drug that is used as a last resort in humans or animals with resistant bacterial infections might be unacceptable from a public or population health perspective. Veterinarians could therefore face the difficult choice of treating animals with a drug that is less likely to be successful, possibly resulting in prolonged or exacerbated morbidity, to protect the good of society. The Committee recommends that voluntary actions be taken by the veterinary profession to promote conservative use of antimicrobial drugs to minimize the potential adverse effects on animal or human health. The veterinary profession must work to educate all veterinarians about issues related to conservative antimicrobial drug use and antimicrobial resistance so that each individual is better able to balance ethical obligations regarding the perceived benefit to their patients versus the perceived risk to public health. Specific means by which the veterinary profession can promote stewardship of this valuable resource are presented and discussed in this document. 相似文献