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61.
The clinical signs and pathological features of back muscle necrosis (BMN) in four pigs from three English pig herds were similar to those recorded in pigs from mainland Europe. The observations made support the view that BMN is a special manifestation of the porcine stress syndrome. Diagnosis of acute BMN can be made clinically supported by the analysis of plasma creatine phosphokinase activity and can be confirmed post mortem by macroscopic and microscopic observation on the back muscles. 相似文献
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TF. JUBB P. BRIGHTLING J. MALMO† MT. LARCOMBE GA. ANDERSON SJ. HIDES‡ 《Australian veterinary journal》1989,66(10):334-336
Anoestrous dairy cows in seasonally calving herds in the Macalister Irrigation District of Gippsland, Victoria were treated at the start of the mating period with a progesterone releasing intravaginal device (CIDR). The CIDR was inserted for 7 days and 400 IU of PMSG was injected intramuscularly at removal. There was no clinically useful difference among cows receiving the CIDR, a placebo and untreated cows in the interval from treatment to either first oestrus or conception, the conception rate to first service or percent pregnant by the end of mating. Analyses of data from 2-year-old cows, older cattle, cows calved at least 45 days or cows calved at least 55 days and cows treated 3 weeks after the start of mating did not show improved reproductive performance following treatment with the CIDR. 相似文献
66.
JWA LARSEN N ANDERSON† AL VIZARD‡ GA ANDERSON‡ H HOSTE§ 《Australian veterinary journal》1994,71(11):365-372
SUMMARY A study on 3 farms, each having a preventive strategy for the control of nematode infections, determined the risk factors associated with diarrhoea among Merino ewes in winter. Comparisons were made among groups of mated and unmated ewes with and without treatment with controlled-release capsules containing albendazole. Diarrhoea was assessed from the accumulations of faeces around the breech (dag score) and related to worm egg counts, total worm counts and histopathological findings. The overall prevalence of severe dag in ewes not treated with a capsule was 26% (221/844). In comparison, only 2.7% of treated ewes had severe dag. The adjusted odds ratio on each farm indicated that untreated ewes were between 12 and 16 times more likely to be affected with severe dag than ewes treated with a capsule. The effect of lactation was significant on only one farm whereas initial body weight had no significant effect. There was no significant association between worm egg counts and the occurrence of severe dag. There were significantly more eosinophils in the small intestine of ewes affected with severe dag compared with unaffected ewes. There were no significant differences in mast cell and globule leucocyte numbers between affected and unaffected ewes. This study provides strong evidence that the main cause of diarrhoea among Merino ewes grazing winter and early spring pastures is the ingestion of trichostrongylid larvae even by sheep that have a well-developed protective immune response to these parasites. New strategies for the control of nematode infections are needed to prevent diarrhoea and dag formation in adult sheep. 相似文献
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Adult cockerels of a commercial egg-producing strain did not develop liver haemorrhages when maintained for 12 weeks on a diet containing 400 g rapeseed meal/kg food. Haemorrhages occurred in 43% of laying hens of the same strain as the cockerels and 33% of laying hens of another strain maintained on the same diet for the same period. Oestrogenisation of the male birds did not influence the incidence of haemorrhage. 相似文献
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R. G. Wells 《British poultry science》1972,13(1):13-25
Light‐weight, hybrid pullets were reared on litter at 0.070, 0.093, 0.139 and 0.186 m2 of floor area per bird. Flock size was constant at 400 birds per pen and other related factors of management were standardised. Results showed that the different densities of stocking had no commercially important effect on growth rate, food consumption or viability, but feathering was poorer in the more densely populated groups.
At 18 weeks of age, some of the birds from each treatment were transferred to battery cages and others to deep‐litter laying quarters and records of their performance in terms of egg production and quality, food consumption, mortality and body weight gain were taken over a period of one year. The use of high stocking densities during the preceding rearing stage caused no impairment of the performance of layers kept in batteries, but was possibly responsible for a small decline in productivity of layers housed on deep litter. 相似文献