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231.
232.
Cerebellar abiotrophy in crossbred cattle 总被引:1,自引:0,他引:1
Cerebellar abiotrophy affected 9 of 74 calves sired by a Poll Hereford bull over 2 successive calving seasons. The disease was characterised by episodes of recumbency and ataxia, with hypermetria and wide base stance. Clinical signs commenced between birth and 8 months of age. Two calves which were affected first at 8 months of age recovered clinically 9 months later. Histological lesions were found in the cerebellar cortex of 7 calves and consisted of segmental degeneration and loss of Purkinje cells, and axonal swellings. The clinical signs and pathological findings were consistent with bovine familial convulsions and ataxia, which has not been described previously in Australia. The clinical signs were not attributable to the lesions observed in the cerebellum and an underlying electrophysiological abnormality is proposed. The aetiology of the condition is probably genetic and appears to have a multifactorial basis. 相似文献
233.
Some aspects of the epidemiology of equine salmonellosis 总被引:3,自引:0,他引:3
A survey of 2 horse populations was done to detect the number of asymptomatic faecal excretors of Salmonella sp. 1201 faecal samples from 250 horses hospitalised at the University of Sydney were cultured. Three serotypes, S. typhimurium (4 horses), S. anatum (2) and S. tennessee (1) were isolated from 7 horses (2.8%). None was detected in 75 mares similarly examined at a thoroughbred stud farm. In retrospect, S. typhimurium was also the most common (70%) of the 19 serotypes recovered from 171 horses with clinical salmonellosis seen at Camden, 1969 to 1986. Forty cases occurring since 1983 were reviewed in detail; the mortality rate was high (60%) and an increased proportion was due to S. bovis-morbificans. Five horses developed salmonellosis while hospitalised and it was usually impossible to be certain whether these cases developed from the carrier state into overt disease or resulted from infections acquired in hospital. 相似文献
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SUMMARY The paper describes a program to import and breed black rhinoceros ex situ at Western Plains Zoo in Australia. Nine rhinoceros (7 females and 2 males) captured in 1992 in Chete National Park, Zimbabwe, were transported to Australia via Cocos Island. The veterinary treatment of the animals before and during quarantine in Zimbabwe and on Cocos (Keeling) Islands is described. Three animals died; an adult male on Cocos Islands and a juvenile male and an adult female at Western Plains Zoo, Dubbo, New South Wales. The juvenile male died as a result of trauma sustained shortly after arrival and the two adults after developing a severe hepatopathy. The group of 6 females and an additional 4 males imported from the USA in 1994 have adapted well to captivity and to the climate and environment of central west New South Wales. 相似文献
238.
M Abad DJ Sprecher P Ross RM Friendship RN Kirkwood 《Reproduction in domestic animals》2007,42(2):149-152
Frozen-thawed (FT) boar sperm have a reduced fertile life, due in part to a capacitation-like status induced by cooling. Reversal of this cryocapacitation in vitro by exposure to boar seminal plasma (SP) has been demonstrated. The objective of these studies was to determine the effect of SP on the ability of FT sperm to create an oviductal sperm reservoir following artificial insemination (AI). In Experiment one, 35 pre-pubertal gilts were injected (IM) with 400 IU eCG plus 200 IU hCG to induce oestrus. At detection of oestrus, gilts were inseminated with 3 x 10(9) live sperm, either fresh (FS; n = 13), FT (n = 10), or FT supplemented with 10% v/v SP (n = 12). Gilts were killed 8 h later, their reproductive tracts recovered and the uterotubal junctions (UTJs) flushed to recover sperm. Fewer (p < 0.01) sperm were recovered following FT, compared to FS, inseminations, and there was no evident effect of SP. In Experiment two, 30 pre-pubertal gilts received IM injections of 1000 IU eCG followed by 5 mg pLH 80 h later to control time of ovulation. Gilts were inseminated with 3 x 10(9) live FS sperm (n = 6), FT sperm (n = 15) or FT sperm plus 10% SP (n = 9) at 12 h before ovulation and then sacrificed 8 h later. The UTJs were dissected and flushed for sperm recovery. Fewest (p < 0.001) sperm were recovered following FT insemination and there was no evident effect of SP. These data demonstrate that the size of the sperm reservoir is markedly reduced in gilts inseminated with FT sperm. However, the lack of effect of SP suggested that either it did not reverse cryocapacitation or that such a reversal does not impact the in vivo ability to create a sperm reservoir. 相似文献
239.
采用紫外分光光度法测定氧氟沙星油剂注射液的含量,选择氯仿与无水甲醇作溶剂,于220~400 nm间扫描,在299 nm波长处有最大吸收峰,辅料无干扰.实验结果表明,氧氟沙星浓度在0.5~2.5 μg/mL范围内,其吸收度与浓度呈良好的线性关系.线性方程为A=-0.86×10-2 4.75×10-1 C,r=0.999 9,平均回收率为100.3%,RSD=0.36%(n=5). 相似文献
240.
Amaral JA De Franco MT Zapata-Quintanilla L Carbonare SB 《Veterinary research communications》2008,32(4):281-290
IgY is a chicken egg yolk antibody which has been used for treatment and prophylaxis of gastrointestinal infections. Our aim
was to verify if IgY obtained from chickens immunized with EPEC O111, STEC O111 and STEC O157 is able to show in vitro reactivity and biological activity towards the three bacteria. IgY was obtained from eggs laid before and after immunization
with each bacterium. The preparations of IgY anti-EPEC O111 and anti-STEC O111 shared high reactivity detected by ELISA and
growth inhibition ability towards both bacteria EPEC O111 and STEC O111. Nevertheless, the preparation of IgY anti-STEC O157
showed high reactivity and growth inhibitory effect only towards the homologous strain. Our results showing in vitro biological activity of IgY reinforce its use as an alternative for the treatment or prophylaxis of E. coli infections and encourage the development of in vivo studies for a possible future human therapeutic use. 相似文献