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1.
Adult wethers (n = 750) were lot-fed for 13 days, 8 days or 3 days before a simulated voyage lasting 18 days to examine whether the period of lot-feeding affected the proportion of sheep that ate pelleted feed and their body weight change during simulated shipping. There was no significant difference in the proportion of non-feeders between treatment groups on days 7 and 14 of the voyage. Body weights were not significantly different between the treatment groups on days 14 and 18 of the voyage. Overall body weight loss, from the farm to the end of simulated shipping, was 4.08 kg (+/- 0.28, s.e.m.), 4.58 kg (+/- 0.28) and 4.51 kg (+/- 0.28) in sheep lot-fed for 13 days, 8 days and 3 days, respectively, and was not significantly different between treatments. It was concluded that lot-feeding for 13 days conferred no advantage in body weight or numbers of non-feeders compared with shorter periods in this study.  相似文献   
2.
A survey by means of a postal questionnaire was undertaken to investigate the patterns of work and the need for information of veterinary practitioners in New Zealand. Of the 670 eligible veterinarians, 399 practitioners (60 per cent) participated in the survey. Of these, 38 per cent were in large animal practice (less than 20 per cent of work devoted to cats and dogs) and 31 per cent were in small animal practice (more than 80 per cent of work with cats and dogs). The remaining 31 per cent were in mixed practice, with a workload intermediate between the other two groups. Across the entire sample of practitioners, cats and dogs took up the largest number of veterinary hours per person (1092 hours per year). Dairy cattle were second (438 hours), and horses third (302 hours). Deer and goats ranked next, and each used more veterinary hours per person than did either sheep or beef cattle. Other species comprised very minor parts of the overall workload. Women spent a much higher proportion of their working hours with small animals and a much lower proportion with horses than did men. For other species workload patterns were similar between men and women. In relation to employment of the practitioner group, women were under represented, compared with men, among those with responsibilities for the management of practices, even when account was taken of the fact that the women in the sample were younger. Fewer than one per cent of men in the sample were not employed full-time, whereas 15 per cent of the women were in part-time employment. The survey indicates that there has been a substantial change in the demographic structure of the veterinary profession and the forms of veterinary work carried out. It also shows that the differences in work and career patterns between men and women need more intensive study to improve the accuracy of predictions of future requirements for veterinary manpower.  相似文献   
3.
The present study was designed to examine the effects of cell-cycle synchronization protocols, such as confluent, roscovitine treatment and serum starvation, in bovine foetal fibroblasts on synchronization accuracy at G0/G1, viability, apoptosis, necrosis and ploidy for use as a nuclei donor. The cells in 5-10 passages were randomly allocated into three treated groups. Cells were cultured either in Dulbecco's modified Eagle's medium (DMEM) + 10% foetal bovine serum (FBS) until 90% confluent (group 1, confluent), in DMEM + 10% FBS + 30 microM roscovitine for 12 h (group 2, roscovitine), or in DMEM + 0.5% FBS for 5 days (group 3, serum starvation). Most of the cells (>80%) in all groups were arrested at the G0/G1 stage. Although the rates did not differ, cells in group 1 showed an increased cell population arrested at the G0/G1 phase. Significantly (p < 0.05) higher rates of apoptosis occurred in group 3 than in group 1 and 2 (10% vs 6% and 6%, respectively). No differences in chromosomal abnormality were observed among groups. However, by increasing the number of cell culture passages up to 15, significantly (p < 0.05) higher chromosomal abnormality was observed than in 5 and 10 passages (39% vs 28% and 23%, respectively) in group 1. The results clearly indicated that bovine foetal fibroblasts could be effectively synchronized at G0/G1 stages by all the three different treatments, confluent, roscovitine and serum starvation. However, cells in confluent showed reduced apoptosis and necrosis when they underwent 5-10 passages, exhibiting increased percentage of cells with stable chromosome diversity. Hence, cells in confluent merit further studies before they could be used as nuclear donors.  相似文献   
4.
Samples taken at various points along the processing line in 2 rendering plants showed that post-processing contamination occurs almost immediately after termination of the heat process in the percolator and surge bin. Further contamination occurs at each processing stage. In plant A 12.5% of the samples collected from material leaving the surge bin, 36% of the samples of product after it has passed the milling stage and 61% of samples collected from the stored product were found to be contaminated with salmonellas. In plant B the results were 15%, 40% and 69% respectively. Heavy contamination of product left overnight in percolators and surge bins, which are not cleaned routinely, was considered an important source of early post-processing contamination. The ecology was found to be similar at both plants despite the fact that in one plant the uncooked and cooked areas were separated completely, whilst this was not the case in the other plant. None of the air samples collected yielded salmonellas, while nearly all the insect samples collected in the rendering plants yielded salmonellas.  相似文献   
5.
Thirty of 52 pedigree Suffolk lambs (58 per cent) were born with arthrogryposis characterised by bilateral flexion rigidity of the metacarpophalangeal and carpal joints. The recent introduction of a breeding ram was identified as the only significant risk factor in the flock, and embryo transfer was used to test the hypothesis that the arthrogryposis was an inherited disorder associated with the introduction of this ram. Two adult ewes that had previously produced lambs with arthrogryposis by the ram and four of its affected daughters were available as donors, and 20 crossbred ewes were used as recipients. Ten Suffolk-crossed ewes that had no known familial relationship with the ram were also mated by the ram as controls and they produced 10 normal lambs. Following embryo transfer, 19 lambs were born, of which seven were stillborn; arthrogryposis was evident in 10 of the 12 live lambs. Analysis of the data suggested that in the population under study, arthrogryposis was inherited as an autosomal recessive condition.  相似文献   
6.
J.P. Day  T.M. Boland  T.F. Crosby   《Livestock Science》2006,100(2-3):270-275
One hundred and eight Texel sired lambs were weaned at 37 days old and allocated three days later to one of two treatments, using two pens per treatment, in order to evaluate lamb hepatic copper (Cu) values. In Treatment 1 (T1) the lambs were confined to pens having recycled plastic slatted flooring, while in Treatment 2 (T2) the lambs were confined to pens having straw bedded floors, with fresh straw added on alternate days. The lambs had ad libitum access to a coarse lamb concentrate. The crude protein (g/kg DM), crude fibre (g/kg DM), total zinc (mg/kg) and background levels of copper (Cu) (mg/kg) and molybdenum (Mo) (mg/kg) of the diet were 17.2, 10.9, 152, 9.7 and 0.92, respectively. The lambs were slaughtered when they reached about 39 kg live weight. Following slaughter, the liver was removed and weighed and the caudal lobe frozen for subsequent Cu analysis. The livers of lambs on the plastic floor treatment had higher liver weights (843 vs. 804 g, S.E.M. 11.0; P < 0.05) and higher hepatic copper (396 vs. 315 mg/kg DM, S.E.M. 18.2; P < 0.05) than those from lambs that were bedded with straw. The Cu accumulation per kg of liver DM per week was estimated to be 8.4 and 13.7 mg for lambs on the straw bedding and plastic slated treatments, respectively. It is concluded that when lambs are housed on plastic slatted flooring, relative to straw bedding, there is a higher accumulation of hepatic copper levels likely to result in a greater risk of Cu toxicity when lambs are reared on all concentrate diets.  相似文献   
7.
8.
In the first of 2 experiments, a simulated voyage was conducted to examine the effects of various treatments on bodyweight change and feeding frequency of inappetant sheep at the end of lot-feeding (non-feeders). The treatments, applied during simulated shipping, were: normal quantities of feed and length of troughs; extra trough length; extra feed. Adult Merino wethers (n = 108) were used in each treatment. A voyage to the Middle East was then conducted to establish whether shipboard mortality could be reduced by separating non-feeders (n = 305) from feeders (n = 5,620) late in the feedlot hase and housing the groups separately aboard ship. A control group of non-feeders (n = 215) mixed with feeders (n = 5,732) was used for comparison. Bars (marker bars), containing a coloured dye, were attached to feed troughs to mark sheep that fed. Most non-feeders (82%) began eating when placed in shipping pens in both studies. However, there was no significant difference in percentage of sheep that fed between non-feeders given extra trough length or extra feed compared with non-feeders given standard management at any stage of simulated shipping. There was no significant difference in mean bodyweights between treatment groups on days 1, 8 and 15 of simulated shipping. Differences in bodyweight on d 22 were probably associated with different levels of gut fill. Death rates were not significantly different in separated and control groups (1.1%, 0.9%, P = 0.6) in the voyage of 14 d to the Middle East.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
9.
The International Centre for Research in Agroforestry (ICRAF) is a member of the Consultative Group on International Agricultural Research (CGIAR) system and has recently established a Multipurpose Tree Germplasm Resource Unit (MPT-GRU) in Nairobi, Kenya. The first major activity of the MPT-GRU was to undertake a regional germplasm collection ofSesbania in 5 countries in southern Africa in a collaborative mode with National Agricultural Research Services (NARS). The collections took place in Botswana, Malawi, Namibia, Zambia and Zimbabwe.Key elements of a generalised collaborative mode (the model) are indicated follwed by a summary of actual events. The initial phase involved joint planning and training sessions between NARS, three sister CGIAR centres and one regional institution, the Southern Africa Development Conference (SADC) Regional Gene Bank (SRGB). This was followed by actual collections during 1993 led by National scientists with different levels of CGIAR participation in each of the five countries. The International Board of Plant Genetic Resources (IBPGR) took the lead in pre-collection training activities, ICRAF for developing the collection programme and the International Livestock Centre for Africa (ILCA) for seed drying, testing and despatch for field trials. NARS gene banks guided the necessary administrative processes. The ICRAF lead scientist for the species and provenance evaluation phase was a crucial member of the planning process thus allowing integration of the collection with the eventual field evaluation. The article focuses on the collection strategy, administrative protocols for actual collections and summary results. Some advantages and difficulties associated with the collection programme and model are discussed. The collections were important in bringing together agriculturalists and foresters in a common germplasm collection exercise.  相似文献   
10.
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