母猪卧向行为学的观察

本文通过2个试验对母猪在分娩圈和分娩栏中的卧向行为进行了观察,试验一中, 选择10头大白(Yorkshire)经产母猪作为观察对象,试验二中分别选择10头大白(Yorkshire) 经产母猪和10头长白(Landrace)经产母猪作为观察对象。观察采用瞬时记录方法,每周观察 三次,隔日观察,每天上午、下午各观察一次,每次3 h,每次观察间隔5 min。观察中发现,母猪 卧向以向外为主。分娩栏(四周是栏杆)中的母猪以选择卧向外(向北)为主,其次是卧向内(向 南),卧向左和卧向右最少且差异不显著,上栏前和下栏后差异不显著。分娩圈(四周是墙壁)中 母猪以选择卧向外为主,卧向内最少,卧向左和卧向右差异不显著。长白母猪比大白母猪选择 卧向外的多,妊娠阶段比哺乳阶段选择卧向外的多。     

烯丙孕素口服液调控母猪同期发情的研究进展

烯丙孕素口服液在国外已被广泛用于母猪同期发情,给药期间可抑制母猪发情,停止给药后重新释放天然激素,母猪会重返发情,以达到同步发情。详细阐述了烯丙孕素口服液的作用机制、药代动力学、临床应用、残留以及毒性,以期为其研究与开发提供一定的参考。烯丙孕素口服液在治疗性成熟母猪同期发情上有较好的应用前景。     

Methyl donors dietary supplementation to gestating sows diet improves the growth rate of offspring and is associating with changes in expression and DNA methylation of insulin‐like growth factor‐1 gene

The study aimed to investigate the effects of maternal dietary methyl donors on the performance of sows and their offspring, and the associated hepatic insulin‐like growth factor‐1 (IGF‐1) expression of the offspring. A total of 24 multiparous sows were randomly fed the control (CON) or the CON diet supplemented with methyl donors (MD) at 3 g/kg betaine, 15 mg/kg folic acid, 400 mg/kg choline and 150 μg/kg VB₁₂, from mating until delivery. After farrowing, sows were fed a common lactation diet through a 28‐days lactation period and six litters per treatment were selected to be fed until at approximately 110 kg BW. Maternal MD supplementation resulted in greater birthweight (p < 0.05) and increased the piglet weights (p < 0.01) and litter weights (p < 0.05) at the age of day 28, compared with that in CON group. The offspring pigs in the MD group had greater ADG (p < 0.05) and tended to lower F:G ratio (p = 0.07) compared with that of CON group from day 28 to 180 of age. The offspring pigs from MD group had greater serum IGF‐1 concentrations and expressions of hepatic IGF‐1 gene and muscular IGF‐1 receptor (IGF‐1r) protein at birth (p < 0.05), and greater hepatic IGF‐1 protein (p = 0.03) and muscular IGF‐1r gene expressions (p < 0.05) at slaughter, than that from the CON group. Moreover, the methylation at the promoter of IGF‐1 gene in the liver of newborn piglets and finishing pigs was greater in the MD group than that of the CON group (p < 0.05). In conclusion, maternal MD supplementation throughout gestation could enhance the birthweight and postnatal growth rate of offspring, associated with an increased expression of the IGF‐1 gene and IGF‐1r, as well as the altered DNA methylation of IGF‐1 gene promotor.     

Free-range system and supplementation of 25-hydroxicholecalciferol increases the performance and serum vitamin levels in mixed-parity sows

Improvements in sow productivity have raised questions regarding dietary vitamin D recommendations. The present study aimed to evaluate the effects of the housing system with access to sunlight exposure and supplementation of 25-hydroxicholecalciferol on performance and serum levels of 25(OH)D₃ in sows during gestation and lactation. Sows were distributed in an experimental design with two housing systems: gestation crates or gestation free-range system with external area for sunlight exposure; and two diets: 0 or 50 μg of 25-hydroxicholecalciferol kg⁻¹. The use of 25-hydroxicholecalciferol tended (P = 0.052) to improve total born and influenced (P = 0.046) on number of born alive. Litter weight at birth was also increased (P = 0.01) by 25-hydroxicholecalciferol supplementation; 25-hydroxicholecalciferol supplementation and housing system (free-range with sunlight exposure) tended to increase weaning weight (P = 0.07) and litter daily gain (P = 0.051) during lactation. Exposure to sunlight and 25-hydroxicholecalciferol supplementation increased 25(OH)D₃ serum levels when compared with control treatment during gestation (136.95 vs. 113.92 ng mL⁻¹; P = 0.035) and lactation (120.29 vs. 88.93 ng mL⁻¹; P = 0.026). In conclusion, the association of 25-hydroxicholecalciferol supplementation with exposure to sunlight during gestation improved significantly 25(OH)D₃ serum levels and consequently performance traits in gestation and lactation.     

超额储备后备母猪的运作模式——非洲猪瘟背景下集团化养猪企业的盈利之道

集团猪场代表行业最高技术、管理及现代化水平,迅速发展。特别是2018年非洲猪瘟疫情在我国暴发后,在高风险、高回报的行业背景下,集团化养猪企业凭借资金、人才、技术、硬件设施等优势,采取超额储备种猪的运作模式,进而迅速扩张。超额储备的本质是利用资金充足、场区数量、生物安全等优势,通过统一使用长白或大白公猪配种,育肥场用作种猪场等方式超额储备后备母猪。个别场区清场后可以迅速引种补栏,多余后备母猪、妊娠母猪正常出售回收资金。这种模式可有效降低风险、保证足够盈利,同时在非洲猪瘟疫情的背景下有效整合农业资源、利用商业资金反哺养猪业,指引养猪行业走向。     

A review of factors influencing litter size in Irish sows

Many factors influence litter size. These include genetics, gilt management, lactation length, parity distribution, disease, stress and boar fertility. In the past 20 years, litter size in Irish sows has increased by only one pig. Born alive figures now average at 11.2 pigs per litter. In this regard, Ireland is falling behind our European competitors who have made significant advances over this time. Denmark, for example, has an average figure of 12.7 pigs born alive per litter and France an average of 12.5. The single area that could be improved immediately is sow feeding. It is important that sows are fed correctly throughout pregnancy. If over-fed during pregnancy, sows will have depressed appetite during lactation. If underfed in pregnancy, sows will be too thin at farrowing. The correct way to feed a pregnant sow is to match her feed allocation to her requirement for maintenance, body growth and growth of her developing foetuses. During lactation, sows should be given as much feed as they can eat to prevent excessive loss of body condition. Liquid-feed curves should be such that lactating sows are provided with a minimum mean daily feed supply of 6.2 kg. A small proportion of sows will eat more and this could be given as supplementary dry feed. Where dry feeding is practised in the farrowing house, it is difficult to hand-feed sows to match their appetite. Ideally ad libitum wet/dry feeders should be used. From weaning to service, sows should once again be fed ad libitum. If liquid feeding, this means giving at least 60 MJ DE (digestible energy) per day during this period. If dry feeding, at least 4 kg of lactation diet should be fed daily. The effort spent perfecting sow feeding management on units should yield high dividends in the form of increased pigs born alive per litter.     

基于MFO-LSTM的母猪发情行为识别

及时准确识别母猪的发情行为可以有效增加受胎率和产仔量,对提高养殖企业的繁育水平和经济效益具有重要意义。该研究针对生猪养殖过程中母猪发情行为识别存在主观性强、智能化水平低、假警报和错误率高、识别不及时等问题,提出了一种基于飞蛾扑火算法(Moth-Flame Optimization,MFO)优化长短时记忆网络(Long Short Term Memory,LSTM)的母猪发情行为识别方法。利用安装在母猪颈部的姿态传感器获得母猪姿态数据,然后使用姿态数据训练MFO-LSTM姿态分类模型,将母猪姿态分为立姿、卧姿和爬跨3类。通过对姿态分类结果进行分析,确定以爬跨行为和活动量2个特征作为发情行为识别依据,使用MFO-LSTM分类算法判断母猪是否发情。以山西省太原市杏花岭区五丰养殖场的试验数据对该方法进行验证,结果表明,该方法在以30 min为发情行为识别时间时的识别效果最好,发情行为识别的错误率为13.43%,召回率为90.63%,特效性为81.63%,与已有的母猪发情行为识别方法相比错误率降低了80%以上。该方法在保证识别准确率的情况下有效降低了错误率,可满足母猪养殖生产过程中发情行为自动识别要求。     

基于隐马尔科夫模型的深度视频哺乳母猪高危动作识别

哺乳母猪的高危动作和仔猪存活率有密切关系,能直接体现其母性行为能力,而这些高危动作又与其姿态转换的频率、持续时间等密切相关。针对猪舍环境下,环境光线变化、母猪与仔猪黏连、猪体形变等给哺乳母猪姿态转换识别带来的困难。该文以梅花母猪为研究对象,以Kinect2.0采集的深度视频图像为数据源,提出基于Faster R-CNN和隐马尔科夫模型的哺乳母猪姿态转换识别算法,通过FasterR-CNN产生候选区域,并采用维特比算法构建定位管道;利用Otsu分割和形态学处理提取疑似转换片段中母猪躯干部、尾部和身体上下两侧的高度序列,由隐马尔科夫模型识别姿态转换。结果表明,对姿态转换片段识别的精度为93.67%、召回率为87.84%。研究结果可为全天候母猪行为自动识别提供技术参考。     

组合式分娩栏对母猪活动和躺卧的影响

为了研究不同型式分娩哺育栏对母猪行为的影响,该试验设计了组合式分娩哺育栏,并进行了饲养试验,同时与普通矩形分娩哺育栏进行了比较。分别记录母猪在哺乳期的采食量以及仔猪的日增质量。在母猪哺乳期的第9、11、14、18天,采用监控设备对8头母猪的行为进行了录像。试验结果表明：组合式和矩形分娩哺育栏内母猪的站立时间分别占各种行为发生时间的22.74%和6.73%,坐立时间分别占2.22%和7.72%,躺卧行为分别占72.50%和84.55%,组合式分娩哺育栏内母猪走动时间占1.13%,矩形分娩哺乳栏内母猪不发生走动行为。组合式分娩哺育栏组母猪的姿势转换次数高于矩形分娩哺育栏组,每天平均数分别为99次和53次。组合式分娩哺育栏组和矩形分娩哺育栏组每头母猪的采食量分别为5.92 kg/d和5.24 kg/d,仔猪日增质量分别为229.93 g/d和224.85 g/d。组合式分娩哺育栏增加了母猪的活动空间,减少了对母猪身体的限制,母猪可以自由的表达各种行为,母猪的活动量增加,提高了母猪的福利状况,母猪的采食量和仔猪的日增质量因此而得到提高,提高了母猪的生产性能。     

中草药验方对乏情母猪繁殖性能的影响

试验选择由卵巢机能失调、子宫炎、阴道炎为主要原因引起的乏情母猪,通过中草药制剂和西药促性腺激素进行催情治疗的效果比较。证实了中草药验方对乏情母猪具有较好的提高繁殖性能的作用。