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1.
Microcomputer systems were placed in three veterinary practices each serving three farms (bureau), and onto nine dairy farms (on-farm). Over a twenty-four week period, the utilization of the computer system and the DHM software was monitored. The on-farm system was more costly in terms of equipment and technical support effort, but the information was utilized to a greater extent than it was by the bureau participants who had invested more user time per cow. Note that actual time will vary with the software program used. The farmers indicated that they wished to have access to the information offered by the software. `Computer phobia' was not found to be a problem. The expectations of the computer system and its benefits generally remained high. In general, the information available through the microcomputer system and the DHM software was found to be useful to both the dairy farmers and the veterinarians in this study.  相似文献   
2.
Soil analysis has established that limestone quarrying dust has entered an adjacent limestone heath of high conservation value. The soil profiles of calcium distribution, established by many years of leaching, have been seriously altered by surface enrichment. It is suggested that the calcicole—calcifuge vegetation of the shallowest soils may be threatened by these changes and it is considered very desirable that further pollution of the site should if possible be prevented.  相似文献   
3.
Calving records for daughters of 667 Record of Performance tested sires were examined to study factors related to age at first calving. For the 3025 heifers analyzed, mean age (± SD) at first calving was 791.5 ± 161.6 days (26.4 ± 5.4 months). There were significant effects of the breed of sire on age of heifer at first calving. Daughters of Angus sires calved earlier than daughters of Charolais, Hereford, Limousin, and Simmental sires. Mean ages at first calving for daughters of Hereford, Limousin, and Simmental bulls were significantly (p < 0.05) correlated with the sire's end-of-test age-adjusted scrotal circumference, but these correlations were not significant when farm effects were controlled. It appears that unknown herd level factors are more important in determining age at first calving in Ontario herds than using early maturing sires as determined by scrotal circumference measurements.  相似文献   
4.
A microcomputer-based herd management information system was implemented as part of the herd health program provided to 13 dairy clients by the Ontario Veterinary College, University of Guelph. The study was conducted over a two year period. Data were collected from on-farm event diaries, veterinary visit reports, and production testing information. Selected indices of reproduction, udder health, production, and heifer performance were reported. It was concluded that the implementation of a microcomputer-based information management system, operated as a bureau service, was feasible. However, limitations to the implementation in veterinary practice were identified.  相似文献   
5.
This study examines the results of bacterial culture from 159 endometrial biopsy samples from 97 commercial dairy cows and correlations between bacteriological and histological findings. Bacteria were isolated from approximately 80% of biopsies taken at day 26 and day 40 postpartum. Eleven percent of biopsies were positive for both aerobic and anaerobic culture. Streptococci, Escherichia coli and Actinomyces pyogenes were the most common isolates. Isolation of A. pyogenes from a biopsy at day 26 was positively correlated with isolation of anaerobic bacteria and segmented cell inflammation in the same biopsy, and with subsequent isolation of A. pyogenes at day 40. There was a strong association between isolation of A. pyogenes and anaerobes at day 26 with increased uterine lesions at day 40. Isolation of alpha hemolytic streptococci (AHS) was negatively correlated with isolation of A. pyogenes and with inflammation. Actinomyces pyogenes and AHS showed opposite associations with mononuclear cell inflammation and lymphocytic foci.  相似文献   
6.
Landscape Ecology - Neutral landscape models are useful and popular tools for exploring effects of spatial patterns on ecological processes. Most neutral landscape models mimic natural landscape...  相似文献   
7.
Endometrial biopsies were taken for histological assessment from 97 cows which calved in a commercial dairy herd between April and August 1984. Sixty-two cows were biopsied at both day 26 and 40 postpartum, 23 cows at only day 26, and 12 at day 40 only. Subjective and quantitative histological criteria were assessed. Ninety-five percent of biopsies were adequate for at least subjective assessment. The distribution of criteria within each horn-day category, as well as combined readings by day and by gravid or nongravid horn were computed and significant differences noted. There was more severe inflammation and more segmented cells at day 26 than 40 postpartum, and in the gravid compared to the nongravid horn. The distribution patterns for the criteria examined provide an overview of histological characteristics in this group of postpartum cows.  相似文献   
8.
Endometrial biopsies were taken for histological assessment from 97 cows which calved in a commercial dairy herd between April and August 1984. The main objectives of this study were to analyze the interrelationships among histological criteria and to identify a shortlist of histological parameters to be included in subsequent analysis of associations with results of bacteriological culture, clinical findings and reproductive performance. Epithelial height and segmented cell counts were highly correlated within biopsy, between horns and between days. Subjective assessment of inflammation in the epithelium and/or stratum compactum generally identified biopsies which had any inflammation present. Cows which had inflammation in a biopsy from day 26 were likely to show inflammatory changes at day 40. Quantitative and subjective assessments of gland number, dilation and fibrosis were highly correlated. There was a positive association between the number of cross sections and the diameter of glands, and both of these criteria were negatively correlated with fibrosis and inflammatory changes. There may be different functional significance of the same histological finding at a different number of days postpartum.  相似文献   
9.
10.
Three hundred and five Holstein Friesian cows were given either 250 micrograms gonadotrophin releasing hormone (GnRH) or saline on day 15 postpartum followed by 500 micrograms cloprostenol or saline on day 24 postpartum. Four treatment groups were formed using random allocation: Group I -- placebo (Day 15)/placebo (Day 24), Group II -- GnRH (Day 15)/placebo (Day 24), Group III -- placebo (Day 15)/cloprostenol (Day 24), Group IV -- GnRH (Day 15)/cloprostenol (Day 24). Double blind techniques were used during the follow-up period. Rectal palpation, to assess uterine involution and ovarian activity was performed just prior to each treatment and again at 28 days postpartum. In addition blood samples were collected at 15, 24 and 28 days postpartum for measurement of plasma progesterone. There were no significant differences among treatment groups with respect to services per conception, number of heats detected before first service and culling for infertility. Cows treated only with GnRH had an increased calving to first estrus and calving to first breeding interval, and tended to have an increased calving to conception interval. Treatment with cloprostenol significantly decreased calving to conception and calving to first observed estrus intervals. Treatment with GnRH on day 15 postpartum resulted in a significant increase in the subsequent incidence of pyometra and prebreeding anestrus. On the other hand, cloprostenol treatment on day 24 postpartum resulted in a decreased incidence of pyometra, regardless of GnRH treatment and a decreased incidence of prebreeding anestrus in GnRH treated cows compared to cows receiving only GnRH at day 15 postpartum.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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