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Objectives

To describe colostrum management practices carried out in northern Victorian dairy herds and to identify weaknesses in these areas that may affect calf health and welfare by comparing the results with the current industry recommendations

Methods

A questionnaire to obtain information about colostrum management and calf‐rearing practices was sent to commercial dairy farming clients of Rochester Veterinary Practice between June and September 2013. The questionnaire consisted of a general herd overview and colostrum harvesting practices.

Results

The response rate was 39% (58/150). Many dairy producers were not meeting the current industry recommendations in the following areas: (1) time of removal calf from the dam, (2) relying on calf suckling colostrum from the dam to achieve adequate passive transfer, (3) failing to supplement calves with colostrum, (4) feeding inadequate volumes of colostrum, (5) delayed colostrum harvesting, (6) pooling of colostrum, (7) failing to objectively assess colostrum quality or relying on visual assessment and (8) storing colostrum for a prolonged periods of time at ambient temperatures.

Conclusion

The results from this survey highlight the need for greater awareness of industry standards for colostrum management and feeding hygiene.
  相似文献   
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The purpose of this article is to provide a review of the current knowledge and opinions about the epidemiology, clinical findings (including sequelae), diagnosis, treatment and monitoring of equine pituitary pars intermedia dysfunction, particularly in the Australian context. This information and the recommendations provided will assist practitioners in making informed decisions regarding the diagnosis and management of this disorder.  相似文献   
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As in other species, the reproductive tract in pigs increases in size with age and body weight, and the development of the reproductive tract depends on a balance between development of the pituitary–ovarian axis and the influence of metabolic hormones. Two experiments were conducted in prepubertal Duroc gilts, 150–180 days of age, to determine whether litter size is related to vaginal–cervix catheter penetration length during insemination. In experiment 1, oestrus was induced in 452 gilts with a combined dose of 400 IU Pregnant Mare Serum Gonadotrophine (PMSG) + 200 IU human chorionic gonadotropin (hCG). The gilts were classified into three catheter penetration length groups: Ih, ≤ 21 cm; IIh, > 21 and < 28 cm; IIIh, > 28 cm. The litter size was lowest in group Ih (7.35 ± 0.15) compared with groups IIh (7.81 ± 0.12; p < 0.05) and IIIh (10.0 ± 0.36; p < 0.001). In experiment 2, first oestrus was induced in 162 gilts by boar exposure. The gilts were classified into three catheter penetration length groups at insemination during their second oestrus: In, ≤ 24 cm; IIn, > 24 and < 26 cm; IIIn, > 26 cm. As in experiment 1, the litter size was lowest in the group with the shortest catheter penetration length (8.32 ± 0.19). The litter size was not different among gilts of groups IIn and IIIn (8.84 ± 0.35 and 9.56 ± 0.46, respectively), but litter size was lower (p < 0.05) in group In than in group IIn. Based on the combined data from both experiments, the correlation between the catheter penetration length and total number of piglets born was expressed as: y=5.346 ± 0.104x; r=0.361 (p < 0.05). Fertility rate was not different among the groups of gilts induced into oestrus by hormone treatment or inseminated in the second oestrus; however, the total fertility rate of boar‐exposed gilts was higher (p < 0.0001) than PMSG/hCG treated animals. Thus, it is possible to conclude that litter size at first farrowing is associated with vaginal–cervix catheter penetration length during insemination of the gilt.  相似文献   
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An enzyme-linked immunosorbent assay has been shown to detect antibodies in the circulation of sheep infected with Psoroptes ovis. Strong positive reactions were obtained from 19 sheep with four-month-old infections. No cross reaction was observed with sera obtained from sheep infected with either Fasciola hepatica, Nematodirus battus, Ostertagia circumcincta or Damalinia ovis.  相似文献   
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Crossbred progeny sired by either Duroc or Pietrain boars, normal for the ryanodine receptor gene, were evaluated for carcass composition and meat quality. Boars from each breed were mated to Yorkshire or F1 Yorkshire-Landrace females. A total of 162 off-spring was evaluated for carcass and meat quality traits at a common age (approximately 26 wk of age). Duroc-sired progeny had heavier (108.0 vs. 103.0 kg, P < 0.001) and longer carcasses (86.9 vs. 84.8 cm, P < 0.01), whereas Pietrain-sired pigs had less backfat at the first rib (44.6 vs. 47.7 mm, P < 0.01), last lumbar vertebrae (20.9 vs. 23.0 mm, P < 0.05), and 10th rib (23.0 vs. 25.5 mm, P < 0.01). No difference between Pietrain and Duroc progeny was detected for fat depth at the last rib (27.8 vs. 28.8 mm, respectively). Pietrain progeny had a higher percentage of lean at slaughter (52.6 vs. 50.7, P < 0.05) and higher dressing percentage (74.0 vs. 73.1, P < 0.01). Primal cut weights were collected with Pietrain progeny having a greater percentage of carcass as ham (23.0 vs. 22.4, P < 0.01) and loin (21.6 vs. 21.2, P < 0.05), whereas Duroc progeny had a higher percentage of belly weight (12.0 vs. 11.7, P < 0.05). Percentages of Boston butt (8.8 vs. 9.0) and picnic shoulder (9.9 vs. 9.9) were similar for Duroc vs. Pietrain progeny. Total weight of these five primal cuts, as a percentage of carcass weight, was higher for Pietrain progeny (75.2 vs. 74.3, P < 0.01). With heavier carcass weight, Duroc progeny had greater primal cut weights as a function of age. Subjective meat quality scores for color, marbling, and firmness (1 to 5 scale) were more favorable for Duroc-sired progeny. Furthermore, chops from Duroc progeny had higher 24-h pH (5.53 vs. 5.48, P < 0.001) and Minolta a* (17.33 vs. 17.04, P < 0.05) with less percentage drip loss (2.88 vs. 3.80, P < 0.001). No differences were detected between Duroc- and Pietrain-sired progeny for Minolta L* (54.77 vs. 55.37) or b* (7.58 vs. 7.58) objective color scores, percentage cooking loss (28.63 vs. 29.23), or Warner-Bratzler shear force (6.94 vs. 7.11 kg). Both sire breeds have beneficial traits that can be utilized in commercial pork production and merit further study.  相似文献   
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