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A survey of northern Victorian dairy farmers to investigate dairy calf management: colostrum feeding and management 下载免费PDF全文
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 recommendationsMethods
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.43.
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R Le Get 《Australian veterinary journal》2018,96(8):285-290
When contagious bovine pleuropneumonia (CBPP) was first detected on a farm north of Melbourne, at Bundoora, in 1858, the predominant theory of miasma was being challenged by contagionist theories of disease transmission. This well‐documented case was recorded during a period of change in the scientific assessment of disease and therefore affords an exploration of what aspects of the landscape were considered important for livestock health at the time. Although the introduction, vaccination programs and eventual eradication of CBPP on mainland Australia has been well explored, scholars have neglected this aspect of the disease's history. By comparing 19th century records of farmland with how the site appears today, it is also possible to highlight the limited information provided by contemporary texts, while at the same time developing an appreciation of the ways in which the perception of the rural landscape has changed. This differing perception has implications for the utilisation of these sources for veterinary and environmental historians seeking to understand the mid‐19th century agricultural landscape and how it relates to animal health. 相似文献
45.
Improved milk production through PG–PL system by provision of in‐house shelter management in lactating Murrah buffaloes during winter season 下载免费PDF全文
N. Haque M. Singh S. A. Hossain 《Journal of animal physiology and animal nutrition》2018,102(1):166-174
Comprehensive information on the role of β‐casein and plasminogen–plasmin (PG–PL) system in milk secretion of Murrah buffaloes during winter season is lacking, although effects of cold stress can be ameliorated to an extent by altering microclimate at farm level. Hence, this study was aimed to determine the changes in productivity along with PG–PL system of milk, plasma hormones and metabolites of buffaloes during winter (December–January) season under two different management systems. Average minimum temperature and wind chill index during this season were 7.02 and 12.74 °C respectively. Buffaloes were divided in two groups of six animals each: control and treatment, where treatment group animals were placed in‐house with floor bedding of paddy straw and the control group animals in loose housing system without straw bedding. Physiological responses were recorded, and milk and blood samples were collected at weekly intervals for six‐week experimental period. Under in‐house management system, buffaloes experienced better comfort by alleviating environmental stress as their physiological responses such as respiration rate and pulse rate were significantly reduced (p < 0.01) as compared to the control, which subsequently resulted higher milk yield by 9.92% (p < 0.05). Analysis of milk samples revealed higher concentration of plasminogen (10.6 vs. 8.05 μg/ml; p < 0.01) and β‐casein (p < 0.05), and lower plasmin level (0.299 vs. 0.321 μg/ml; p < 0.05) in buffaloes under treatment group. It was also found that plasma cortisol, glucose and non‐esterified fatty acids levels were higher (p < 0.01) in control group as compared to the treatment animals by 13.6%, 8.14% and 12.6% respectively. However, milk composition, growth hormone, epinephrine and norepinephrine level in plasma were similar in both the groups. Hence, it may be concluded that provision of in‐house shelter management with floor bedding of paddy straw during winter was effective to minimize environmental stress and improved milk production through manipulation of PG–PL system in buffaloes. 相似文献
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根际生命共同体:协调资源、环境和粮食安全的学术思路与交叉创新 总被引:5,自引:0,他引:5
植物营养学研究近年来在植物养分高效分子机理、植物-微生物互作、根际互作与微生态调控、农田养分管理等研究领域取得了一系列原创性进展。然而,当前如何协调粮食安全、资源高效和环境可持续性仍面临巨大挑战。针对这一重大问题,本文提出"根际生命共同体(Rhizobiont)"学术思路,围绕"根际互作与养分高效"这一重大科学命题,构建"植物-根系-根际-菌丝际-土体及其微生物"根际生命共同体理论体系,突破植物-微生物、微生物-微生物关键界面互作机制,阐明根际生命共同体结构、功能及其在养分活化、吸收与利用中的作用机制,建立共同体多界面互作增效的生物学调控新途径,开辟植物-土壤-微生物交叉创新领域,根际生命共同体理论创新有助于破解粮食安全、资源高效、环境保护多目标协同的难题,支撑我国农业绿色发展。文章指出了根际生命共同体与养分高效研究的重点方向与内容,尤其是深入揭示和调控植物第二基因组——微生物组的作用正成为农业科学的研究前沿。 相似文献
48.
探讨了粮食安全保障体系,即粮食安全的基本概念、保障体系的结构、经济管理机制以及政策效应。粮食安全概念包含四个方面:粮食获取、可达性、利用效率及供应稳定性,其不仅关乎总体生产规模,还涉及资源分配与市场运作。生产力、储备、运输、分配、消费以及政策与管理等多个环节构成了保障体系的架构。经济管理机制的核心关注点包括宏观经济政策、市场调控以及应对市场波动的策略。通过跨国案例研究,揭示了政策在推动农业产出、加强市场稳健性和提升农民生活品质等方面的具体作用。 相似文献
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茚虫威属于噁二嗪类杀虫剂,与大多数杀虫剂不同的是其进入害虫体内需要经活化代谢转变成N-去甲氧羰基代谢物(decarbomethoxylated metabolite,DCJW)后不可逆地阻断钠通道,进而发挥杀虫活性。茚虫威由于其作用机制不同于常见的使钠离子通道延迟关闭的菊酯类药剂而被广泛用于鳞翅目和一些同翅目、鞘翅目害虫的防治。抗药性是任何杀虫药剂使用后面临的问题,茚虫威也不例外,许多害虫对其产生了不同程度的抗性。昆虫对茚虫威产生抗性的机制包括酯酶活性、谷胱甘肽S-转移酶(glutathione S-transferase,GST)和P450活性的增加以及分子靶标F1845Y、V1848I、L1014P的突变,这些对茚虫威抗性机制的研究基本都是基于抗性种群和敏感种群开展的,需要进一步验证其对抗性研究的贡献度。针对我国田间害虫种群对茚虫威的抗性现状,及时实施对茚虫威有效的抗性治理是迫切的。对于茚虫威的抗性治理除了传统的杀虫药剂轮用、混用外,需要利用其作用机制特点开展抗性治理策略研究。一是充分利用其活化代谢的特点,开展组合药剂的研究应用;二是菊酯类药剂和茚虫威的作用机制均与钠离子通道有关,... 相似文献