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1.
In a field investigation of 47 flocks in south Greece, a clinical examination for fertility evaluation was done on 293 rams. In each ram, a general-health examination, examination of the genital organs and libido evaluation were carried out. In 143 (49%) of the 293 rams examined, at least one abnormality was recorded. The median within-flock prevalence risk (PR) of at least one abnormality was 58.0%, that of general-health abnormalities was 33%, that of genital abnormalities was 20% and that of libido abnormalities 14%. The principal abnormalities observed during the general-health examination were interdigital dermatitis, injuries of the sole, blowfly myiasis and brisket sores. The principal abnormalities observed during the examination of the genitalia were testicular hypoplasia, nodules into the testicular parenchyma, ulcerative lesions characteristic of orf in the prepuce and blowfly myiasis on the preputial orifice. The principal abnormalities observed during the evaluation of libido were incomplete erection and inability to mount the ewe. A statistically significant (P<0.05) positive association was recorded between: ram:ewe ratio and general-health abnormalities PR; general-health abnormalities PR and at least one abnormality PR; genital abnormalities PR and libido abnormalities PR; genital abnormalities PR and at least one abnormality PR; lambing percentage and total lambs born per ewe. A statistically significant (P<0.05) negative association was recorded between: ram age and general-health abnormalities PR; ram age and any abnormality PR; general-health abnormalities PR and lambing percentage.  相似文献   
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Objective To examine whether sub-optimal temperature induced stress and immunosuppression in farmed saltwater crocodile (Crocodylus porosus) hatchlings. Design A clinico-pathological study. Animals A total of 140 hatchlings were used. Procedure Body weight and length, plasma corticosterone and immunoglobulin concentrations and total and differential white blood cell counts were measured in 140 hatchlings from five clutches divided between five water temperature treatment groups. Initially all groups were housed at 32°C for 10 weeks, then two groups (L, LC) were changed to low temperature (28°C) and two groups (H, HC) to high temperature (36°C), while one group (C) remained at 32°C. The LC and HC groups were maintained at these temperatures for 10 days, after which the water temperature of both groups was returned to 32°C. Blood samples were collected twice (at 6 and 9 weeks of age) before the initial temperature change, and at 10 days and 4 weeks after the initial temperature change (at 11.5 and 14 weeks of age). Results Except for an increase in plasma corticosterone in the HC group and a decrease in the L group when the temperature change was first introduced, changes in plasma corticosterone were not significant. There were no significant changes in immunoglobulin concentrations. There were, however, significant decreases in the total white cell and lymphocyte counts in the LC group after the temperature was decreased to 28°C, and an increase in these counts after water temperature was returned to 32°C. Clutch of origin had significant effects on body weight and length gains, and there were negative relationships between body weight and corticosterone concentrations and between body weight and immunoglobulin concentrations. Conclusions As haematological changes indicative of stress were not associated with significant changes in serum corticosterone, immunosuppression in young crocodiles may be independent of the hypothalamic-pituitary-adrenal cortical axis.  相似文献   
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AIM: To determine if migratory birds arriving in New Zealand in the Southern Hemisphere spring of 2004 were infected with the highly pathogenic avian influenza (AI) virus, H5N1.

METHODS: Cloacal and faecal samples were collected from migratory red knots following their arrival in New Zealand in October 2004. Two species of resident sympatric birds, wrybill and mallard duck, were sampled prior to, and following, the arrival of migratory birds.

RESULTS: No AI viruses were isolated from migratory or resident shorebirds. Non-pathogenic AI viruses were isolated from six resident mallard ducks, comprising the endemic subtypes H4 (n=2), H7 (non-pathogenic), H10, and H11 (n=2).

CONCLUSIONS: Highly pathogenic AI H5N1 virus was not detected in migratory shorebirds or sympatric water birds in the Firth of Thames, New Zealand, in 2004-2005, despite the possible proximity of migratory birds to outbreaks of the disease in East Asia in 2004.  相似文献   
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The objective of this study was to assess the effects of in‐feed chlortetracycline (CTC) as a measure of preventing or minimizing infectious problems of reproductive failure in gilts and sows. In a farm of 400 Large White × Landrace gilts and sows with a clinical history of porcine respiratory and reproductive syndrome (PRRS) virus, the animals were treated with CTC. Treatment consisted of 10 g CTC sow/day for 15 days every 3 months. It improved the health status of sows by decreasing post‐farrowing clinical mastitis and vaginal discharges, abortions, return‐to‐oestrus and irregular return‐to‐oestrus rates. These beneficial effects had a positive impact on the performance of the litter. More piglets were born live and weaned. These positive effects improved with repeated use of CTC. The serological evidence of PRRS virus, Leptospira spp. and Chlamydia spp. and the subsequent beneficial use of the antimicrobial agent indicate that reproductive failure, possibly resulting from the bacterial agents can be controlled with in‐feed use of broad spectrum antimicrobials.  相似文献   
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Sixty sows suffering from typical post-weaning TSS were divided into three groups: (1) 20 as negative controls (NC); (2) 20 as positive controls (PC) treated with vitamins, trace elements and antibiotics; and (3) 20 injected with amperozide (2 mg/kg body weight), a new neuroleptic compound with antistress and anxiolytic properties. Amperozide treated sows fully recovered (P less than 0.05) and 80% became pregnant, while figures for the PC and NC groups were only 15% and 10% respectively. Mortality was up to 50% in the NC, 40% in the PC and only 15% in the amperozide treated group (P less than 0.05). These field results warrant further studies in unravelling the aetiology and prevention of this condition.  相似文献   
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