Within-flock transmission of sheep scab in naive sheep housed with single infested sheep.

The within flock transmission of sheep scab was studied in two trials, which lasted 14 and 12 weeks, respectively. A total of 40 non-infested, scab-naive sheep were divided into six groups of between 6 and 20 individuals. Each group was subsequently housed with a single infested index case, carrying scab lesions of different ages. The groups of sheep in both trials were video recorded continuously and all the sheep were individually examined on a weekly basis. The occurrence of transmission was measured in two ways: first, by the detection of early scab lesions during clinical examination and, second, by an increase in the rubbing of individual sheep as noted from the analysis of the video recordings. These two methods complemented each other in predicting the week on which transmission occurred. Overall, transmission was detected in 34 of the 40 scab-naive sheep. Transmission was shown to occur at about the time when the population of adult mites in lesions on index cases reached their peak numbers. The highest number of mites at this time, however, differed markedly between index sheep. There was no obvious relationship between the incidence of transmission and the time index sheep spent rubbing each day or other index sheep variables, including the age of the lesion or the time since the introduction to the scab free sheep.     

湖羊和巴什拜羊FSHR基因多态性分析

本文旨在了解绵羊(湖羊和巴什拜羊)促卵泡激素受体(FSHR)基因3'-UTR特征,分析高、低繁殖力绵羊品种FSHR基因3'-UTR突变位点多态性差异,并探索其机制。研究获得788 bp的湖羊和巴什拜羊FSHR基因3'-UTR序列,两者一致性为98.17%,且均含有加尾信号、保守的ARE元件和多个miRNA结合位点;池DNA测序在FSHR基因终止密码子后325nt处发现一个碱基T插入/缺失,命名为*325del T;多态性分析发现绵羊FSHR基因*325del T位点有3种基因型(TT型、T-型和--型),在湖羊群体中T为优势等位基因(频率为0.604),而在巴什拜羊群体中-为优势等位基因(频率为0.635);荧光素酶活性分析发现*325del T突变对绵羊FSHR转录活性无显著影响。发现FSHR基因*325del T的多态性可能与绵羊繁殖性能有关。     

Chemotherapy of brucellosis in rams

Abstract

Extract

Recognition that one infective agent could cause ram epididymitis and ewe abortion in New Zealand was due to McFarlane et al. (1952 McFarlane, D., Jebson, J. L., Hartley, W. J., Salisbury, R. M., McClure, T. J. and Osborne, H. G. 1952. Aust. vet. J., 28: 226–226. [Crossref] , [Google Scholar]). The organism was not identified at that time, but Buddie and Boyes (1953 Buddle, M. B. and Boyes, B. W. 1953. Aust. vet. J., 29: 145–153. [Crossref] , [Google Scholar]) classified it in the genus Brucella—possibly a variant of Br. melitensis. This finding provided a basis for research on control and treatment of the disease. The present paper describes studies on one aspect of this problem, the chemotherapy of affected rams.     

Pasteurellosis in sheep

Pasteurellosis is an important cause of economic loss to the sheep industry. There are two distinct syndromes. The pneumonic form of the disease caused by P haemolytica biotype A occurs as pneumonia in flocks and sporadically in individual sheep. The septicaemic form, caused by P haemolytica biotype T is associated with hyper-acute disease and occurs most commonly in the autumn coinciding with the folding of hoggs on rape, turnips and improved pastures. The factors which predispose sheep to the different forms of the disease are poorly understood but recently it has been possible to reproduce pasteurella pneumonia experimentally.     

Chemotherapy of paramphistomosis in cattle

Controlled tests were used to assess the efficacy of anthelmintics against immature paramphistomes, predominantly Calicophoron calicophorum, in 127 calves which were exposed to contaminated pasture for 7 weeks, treated and slaughtered. When a combination product of oxyclozanide and levamisole was used, oxyclozanide at 18.7 mg/kg reduced parasite numbers in the small intestine, abomasum and rumen-reticulum by 61 to 96.1%, 50.0 to 92.6% and 56.5 to 98.1%, respectively. When 2 doses were given 3 days apart, oxyclozanide was 99.9%, 100% and 100% effective, respectively, in the above organs, and produced improvement in clinically affected calves. This treatment elicited transient diarrhoea. Hexachlorophene at 20 mg/kg as a single dose was 99.5%, 100% and 100% effective against the fluke in the small intestine, abomasum and rumen respectively but severe neurological signs were seen in some calves. Niclosamide at 160 mg/kg given as single or 2 doses 3 days apart was 91.1% and 92.6% effective, respectively, against the parasites in the small intestine. No toxicity was noted. Closantel, at 7.5 mg/kg was not effective. Oxyclozanide and niclosamide when given as a single treatment had varying activity. Two doses of oxyclozanide and a single dose of hexachlorophene gave consistent results. Further tests based on reduction of faecal egg counts, 10 to 14 days after treatment were conducted with oxyclozanide and hexachlorophene against mature paramphistomes in 207 cattle. Oxyclozanide as a single dose or 2 doses 3 days apart at 12.8 to 18.7 mg/kg was 93.6 to 97.5% effective in reducing egg counts. Hexachlorophene at 20 mg/kg was 83.0% effective.(ABSTRACT TRUNCATED AT 250 WORDS)