1例副猪嗜血杆菌病的诊治

本文总结了1例副猪嗜血杆菌病的发病情况、临床症状、解剖病变和诊断,并提出了良好的猪舍环境是猪群快速健康生长的外部条件,也是猪群防病的基本条件。一般猪场可以通过改善饲养管理,控制猪群密度,保证通风良好;减少猪群流动,杜绝大小不同猪只混养;搞好猪场、猪舍清洁卫生、加强消毒、在断奶转群、长途运输前后、药物预防控制发病。     

猪舍通风系统调节技术

影响健康养猪的5个因素分别是品种、环境控制、饲料营养、饲养管理、疫病防治等.随着养猪生产集约化的推进,猪场的养殖密度不断升高,适宜的猪舍环境显得越来越重要,猪舍中的环境控制技术可能会影响猪的饲料转化效率和猪的健康.猪舍中环境控制系统设计需综合考虑通风、降温、采暖、空气质量等因素,应在提高环境调控效率的情况下,降低猪舍环...     

冬季养猪必须重视改善舍内空气质量

有害气体在猪舍内产生和积累,取决于猪舍的封闭程度、通风条件、粪尿处理和饲养密度等因素。近年来,由于集约化养猪,实行封闭管理,饲养密度大,加之管理不善,很容易增加各种有害气体的产生,造成空气污染,导致猪群疾病高发。因此,要想改善猪舍空气质量,使之达到正常水平,必须实施有效调控,努力给猪群创造一个舒适清净的生活环境,才能降低疾病发生率,真正提高养殖效益。     

饲养密度对猪的影响

随着集约化和机械化养猪的发展,养猪企业以及养猪农户为了取得更高的经济效益以及更加高效管理猪群。因此,养殖企业(户)越来越倾向于在单位面积或空间内饲养更多的猪。然而,单位面积或空间内饲养更多的猪会对猪的生长性能、健康以及猪的福利指标产生巨大的不利影响。饲养密度过高,猪舍的环境卫生就会变得越来越差,尤其是空气质量,这会增加猪群呼吸道疾病的风险,从而造成猪疾病的发生,继而降低猪的生产性能。本文主要从猪群饲养密度对环境的影响以及对猪只的影响这两方面阐述适宜饲养密度的重要性,以期为我国养猪业的发展提供指导。     

猪舍内不同季节微生物气溶胶含量及其空气动力学分析

猪舍内环境质量影响猪群的健康和生产水平,而空气中需氧细菌浓度和大肠杆菌浓度指示着猪舍的卫生情况和疾病流行情况。研究了不同季节猪舍内微生物气溶胶变化及其空气动力学直径。结果表明,猪舍内气载需氧菌和大肠杆菌浓度在冬季密闭饲养条件下最高,夏季敞开式通风条件下最低。猪舍环境中约有44.0%的气载需氧菌和45.91%的大肠杆菌粒径大于5μm可进入人和猪的上呼吸道,从而对人及猪的健康构成潜在威胁。19.79%的气载需氧菌和22.65%的大肠杆菌粒径小于2μm,可直接侵入肺泡,严重威胁猪群和饲养管理人员的健康。     

饲养密度对保育猪前期生产效果的影响

饲养密度一般以每头猪所占猪栏或所占猪舍面积来表示。饲养密度的大小直接影响猪舍温度、湿度、通风、有害气体和尘埃微生物的变化的含量，也影响猪的采食、饮水、排泄、活动、休息等行为。例如，每圈养猪头数过多，或每头猪占的面积太少，都会增加猪的咬斗次数，休息时间和采食量都会减少。尤其是夏季，密度过大，会使气流降低，局部环境温度升高，猪的采食量减少，日增重和饲料利用率下降，猪群也容易引发疾病。因此，适宜的饲养密度和群体大小对猪生长有利，如群饲猪比单饲猪吃得快，吃得多，增重也快。国内外虽然也曾对饲养密度对保育猪…     

谁在吞噬动物自卫的“武功”——免疫抑制病在养猪生产中的危害及防治

目前在我国国内已经很少能够找出蓝耳病阴性猪场。专家指出,此病很难净化,净化的方法是全进全出,自繁自养,进行病毒抗原的检测,发现是阳性的及时从猪群中淘汰。种猪、育肥猪要分开饲养,相对隔离。在高温季节,做好猪舍通风和防暑降温,提供充足的清洁饮水,保持猪舍干燥。保持合理的饲养密度,减少猪群转群和混群次数,降低应激因素。不使用霉变和劣质饲料,保证充足的营养,增强猪群抗病能力。环境消毒及时清除猪舍粪便及排泄物,保持环境清洁。定期对猪场环境、圈舍进行消毒,以降低和消除猪场内污染的病原微生物,减少或杜绝猪群的外源性继发感染。在高温季节,应增加消毒次数;发病猪舍每天要消毒1-2次。养殖场只有认真、积极地执行规范化、标准化的饲养方式,才能有效规避或减轻疫病损失,从而提高养猪生产水平。     

环境对养猪业的影响

<正>在养猪业里,猪舍的环境影响着猪的生长发育和对疾病的感受性,因此,为猪群创造适宜的环境,才能保证一年四季的均衡生产,使猪群的遗传性充分显现,饲养效果更好地发挥,保持猪群健康,最大限度地提高生产水平。     

猪传染性胸膜肺炎的防治

一、流行特点各年龄猪均可感染,但以2~5月龄,体重在30~60kg的猪多发;病发有明显的季节性,多在4-5月份和9-11月份发生;此外,饲养环境突变、饲养密度过大、猪舍通风不良、气候骤变及长途运输等都可诱发。初发病猪群的发病率和病     

谈夏季猪群适宜密度与猪舍温湿度调整

夏季气候炎热,降雨量增多,容易形成一个高温高湿的环境,对肉猪生产十分不利。因此,必须给人为控制,创造一个适于肉猪生长的环境条件,不断提高肉猪生产水平。合理调整猪群密度与猪群大小:猪散热主要通过呼吸、排泄粪尿、热传导(猪体与床面接触)、体表辐射等途径。猪群密度过大,由于辐射散热增加,使得舍中温度升高,猪食欲下降,同时也会引起一些疾病的发生(如中暑),不利于肉猪生长;密度过小,会造成猪舍有效面积利用不合理。兼顾肉猪饲养效果和合理使用猪舍面积两个方面,建议每头肉猪不同生长阶段所需面积为:35千克以前0.5平方米/头,35～60千克0…     

The influence of stocking rate on transmission of helminth parasites in pigs on permanent pasture during two consecutive summers

This study was made to elucidate the transmission of nematode infections in outdoor pigs at different stocking rates during two consecutive seasons. Five pigs (Group 1A) inoculated with low doses of Oesophagostomum dentatum, Ascaris suum, and Trichuris suis and five helminth-na?ve pigs (Group 1B) were turned out together in June 1996 on each of four pastures at stocking rates of 100, 240 (two pastures) and 576m(2) per pig, respectively. The pigs were slaughtered in early October, and pasture infectivity was subsequently measured using helminth-na?ve tracer pigs (Tracer). In 1997, 10 helminth-na?ve pigs were turned out on each pasture in May (Group 2) and again in August (Group 3), and allowed to graze for 12 weeks. The percentage of grass cover was reduced considerably at the high stocking rate in comparison to the other stocking rates. Transmission of all three helminths was observed on all pastures. In 1996, the O. dentatum faecal egg counts and worm burdens were significantly higher in pigs at the high stocking rate compared to pigs at the other stocking rates. O. dentatum did not survive the winter and pigs of Group 2 were inoculated with 3000 larvae each to reintroduce this parasite. Ascaris suum ELISA values and worm counts were highest at the high stocking rate in 1997 (Group 3). Transmission of T. suis was not significantly influenced by stocking rate. The results indicate that transmission of O. dentatum, and to some extent A. suum is influenced by stocking rate. However, both A. suum and T. suis eggs are still expected to constitute a high risk of infection on intensively used pastures where eggs may accumulate for years. The relationship between host density and helminth transmission seems more complex for grazing/rooting pigs than for grazing ruminants. This may be due to the differences in behaviour of the animals and the resulting differences in microclimate of the developing eggs/larvae.     

Herd factors associated with the seroprevalences of four major respiratory pathogens in slaughter pigs from farrow-to-finish pig herds

The objective of this study was to investigate sero-epidemiological aspects of Mycoplasma hyopneumoniae (Mh), influenza H1N1 and H3N2 viruses and Aujeszky disease virus (ADV) in fattening pigs from 150 randomly selected farrow-to-finish pig herds. Different herd factors were examined as potential risk indicators for the percentage of pigs with antibodies against the 4 pathogens. The median within-herd seroprevalences of the pathogens were: Mh 76%, H1N1 100%, H3N2 40% and ADV 53%. There was a positive association between the seroprevalences of both influenza viruses, and a negative association between the seroprevalences of ADV and H1N1. The percentage of pigs seropositive for Mh increased with the purchase of gilts and with the season (slaughter date in March-April). The within-herd seroprevalences of both influenza viruses were higher in the case of a higher density of pig herds in the municipality. A higher number of fattening pigs per pen additionally increased the risk of being seropositive for H3N2. The percentage of pigs with anti-gE-antibodies against the wild type ADV increased with higher airspace stocking density in the finishing unit, increasing herd size, increasing number of pig herds in the municipality and slaughter date in March-April. Increased seroprevalences for these 4 respiratory pathogens were mostly associated with pig density in the herd and its vicinity, the winter period, and with the purchase of gilts. Purchase of gilts, number of fattening pigs per pen and airspace stocking density are risk factors that can be managed directly by farmers striving to attain a high respiratory health status of pigs.     

Seroprevalence of Toxoplasma gondii in wild pigs (Sus scrofa) from Spain

Sera collected from 507 hunter-killed wild pigs (Sus scrofa) between 1993 and 2004 from five geographic regions in northern Spain and seven regions in southern Spain were assayed for antibodies to Toxoplasma gondii by the modified agglutination test (MAT). Antibodies to T. gondii were detected in 185 (38.4%) of 507 pigs with titers of 1:25 in 71, 1:50 in 111 and > or =1:500 in 3; seroprevalence was significantly higher (P<0.05) in pigs from southern regions. Seroprevalence was density dependent; it was higher in pigs from high stocking per hectare and availability of forage. Statistically significant differences were not observed between T. gondii seroprevalence and hunting estates (open versus fenced), sex or age. Serological results indicate a widespread exposure to T. gondii among Spanish wild boars, suggesting that this population could represent a public health risk for persons that handle or consume raw or undercooked infected wild pig meat.     

Effects of stocking density on growth performance,blood parameters and immunity of growing pigs

This study was conducted to evaluate the effects of different stocking densities on growth performance, blood parameters, intestinal morphology and intestinal immunity of growing pigs. A total of 288 male pigs (44.35 ± 0.50 kg) were randomly assigned to groups with stocking densities of 2.46, 1.23 and 0.82 m²/pig for a month. The results showed that there was no significant difference on growth performance among groups. Pigs in the stocking density of 0.82 m²/pig had the lowest backfat thickness and spleen weight index among groups (P < 0.05). With increasing stocking density, the serum concentrations of blood urea nitrogen (BUN), transglutaminase (TGG), alkaline phosphatase (AKP) and immunoglobulin A (IgA) were increased, and albumin (ALB), albumin-to-globulin ratio (ALB:GLO), insulin-like growth factor-1 (IGF-1) and immunoglobulin (IgM) were decreased (P < 0.05), and cortisol tended to increase and glucose tended to decrease (0.05 < P < 0.1). Compared with the stocking density of 2.46 m²/pig, the ileal villus height and jejunal villus width decreased in stocking densities of 1.23 and 0.82 m²/pig (P < 0.05). The duodenal villus height and ileal villus width in the stocking density of 0.82 m²/pig were the lowest among 3 groups (P < 0.05). The content of immunoglobulin A in duodenum, jejunum and ileum mucosa increased along with increasing density (P < 0.05). The contents of interleukin (IL)-2 in the spleen or liver and IL-10 in the spleen were higher in the stocking density of 0.82 m²/pig than in other 2 groups. These results showed that stocking density could affect the metabolism, intestinal morphology, and immunity of growing pigs and 1.23 m²/pig may be the suitable stocking density for the growing pigs in the present study.     

Change management reduces antibiotic use on pig farms

A clostridial ‘syndrome’ in suckling and weaner pigs, with risk factors of high injectable ceftiofur use and poor hygiene, presented an opportunity to engage in management change to improve pig health and reduce ceftiofur use on four farms. Management changes included all‐in‐all‐out pig flow, batch disinfection with biofilm control, reduced protein starter diets, appropriate stocking density and the use of an anti‐clostridial probiotic. Assessment of the program was obtained from a questionnaire. The health and production changes were positive across all farms and were associated with reduced use of antibiotics, together with cost and labour savings. Provided there is a good relationship between a committed, competent veterinarian, and a committed, competent manager, change management programs can be successfully implemented over 6–12 months.     

饲养密度和硫辛酸对肉鸡血清指标、行为及骨骼发育的影响

本试验旨在研究高饲养密度条件下饲粮中添加硫辛酸(LA)对肉鸡血清指标、行为及骨骼发育的影响.试验选取健康状况良好、体重相近的1530只21日龄爱拔益加(AA)肉鸡,随机分成3组,即常规饲养密度组(ND组,15只/m2,饲喂基础饲粮)、高饲养密度组(HD组,18只/m2,饲喂基础饲粮)和高饲养密度+LA组(HD+LA组,...     

Effects of Increasing Stocking Density on the Performance and Ileal Microbiota of Broilers

This study was conducted to investigate the effects of increasing stocking density under suitable environmental conditions on the performance and ileal microbiota of broilers. A total of 108 Arbor Acres male broilers (28 days old) were allocated to a normal stocking density (NSD, normal stocking density; 31 kg/m²) and a maximum allowed stocking density group (MSD, maximum stocking density; 39 kg/m²). All birds were reared at a constant temperature of 21°C. At 42 days of age, bacterial DNA was extracted from ileal content, and the V3–4 hypervariable region of 16S rRNA was amplified. Increasing stocking density had no significant effect on average daily gain, average daily feed intake, and feed conversion ratio (P>0.05). The alpha and beta diversities of the ileal microbiomes did not differ significantly between the NSD and MSD groups; however, increasing stocking density altered the composition of ileal microbiota. The relative abundance of Lactobacillales, including Lactobacillus, Enterococcus, and Streptococcus, significantly decreased in MSD broilers, compared with NSD broilers. The present results suggest that even under suitable environmental conditions, an increase in stocking density to a level of 39 kg/m² may disturb the composition of ileal microbiota in broilers. Further studies are needed to determine the reasons and the potential consequences for animal health and physiology.     

饲养密度和高蛋白质饲粮代谢能水平对公母分饲肉鸡生长性能和腿部健康的影响

本试验旨在研究饲养密度与高蛋白质(前期23%,后期21%)饲粮代谢能水平对公母分饲肉鸡生长性能和腿部健康的影响。试验采用2(性别)×2(饲养密度)×3(饲粮代谢能水平)三因子完全随机设计,选用1日龄罗斯308(Ross 308)肉鸡公雏1 872只和母雏2 160只,随机分成12个组,每组8个重复。试验设高、低2个饲养密度,以出栏体重计,分别为42[高饲养密度(HSD),16公/m2或18母/m2]和26 kg/m2[低饲养密度(LSD),10公/m2或12母/m2]。试验饲粮分前期(1~21日龄)和后期(22~35日龄)2个阶段配制,饲粮代谢能设高、中、低3个水平,其中,高代谢能(HME)水平饲粮前期和后期的代谢能水平分别为12.81和13.23 MJ/kg,中代谢能(MME)水平饲粮前期和后期的代谢能水平分别为12.18和12.60 MJ/kg,低代谢能(HME)水平饲粮前期和后期的代谢能水平分别为11.55和11.97 MJ/kg。结果表明:1)饲养密度与饲粮代谢能水平对肉鸡的平均日增重和料重比有显著交互作用(P0.05)。1~21日龄时,随着饲粮代谢能水平增加,HSD组平均日增重的增加幅度和料重比的降低幅度均小于LSD组;22~35日龄时结果正好相反。性别与饲养密度对肉鸡的平均日采食量有显著交互作用(P0.05)。随着饲养密度增加,公鸡平均日采食量的降低幅度大于母鸡。2)HSD极显著降低肉鸡的胸肌率(P0.01),母鸡的胸肌率和腹脂率显著高于公鸡(P0.05)。饲粮代谢能水平和饲养密度对肉鸡的腿肌率有显著交互作用(P0.05)。随着饲粮代谢能水平增加,LSD组肉鸡的腿肌率降低,而HSD组基本不变。3)高饲粮代谢能水平极显著降低肉鸡的脚垫损伤评分(P0.01),公鸡的步态评分和脚垫损伤评分显著高于母鸡(P0.05),垫料水分含量显著低于母鸡(P0.05)。饲粮代谢能水平与饲养密度对肉鸡的脚垫损伤评分有显著交互作用(P0.05)。随着饲粮代谢能水平增加,HSD组脚垫损伤评分的降低幅度大于LSD组。以上结果表明,高饲养密度降低肉鸡的平均日增重,增加料重比;35日龄前,公鸡比母鸡的空间需求更高;提高高蛋白质饲粮的代谢能水平可以缓解HSD对肉鸡生长性能和脚垫健康的不利影响。     

环境富集和饲养密度对绵羊福利的影响

试验主要研究环境富集和饲养密度对绵羊生产性能、血清指标、屠宰性能的影响。选用健康的小尾寒羊24只,分为A、B、C 3组,每组8只,A 组为高集约化模式,B组为高集约化模式+运动场模式,C组为环境富集模式。结果表明,各组绵羊的末重、平均日增重、平均日采食量、饲料转化率差异不显著,环境富集和适宜的饲养密度有提高绵羊生产性能的趋势。环境富集和适宜的饲养密度可以极显著改善前膝清洁度指数（P<0.01）,显著改善后膝、后臀的清洁度指数（P<0.05）;环境富集和适宜的饲养密度能显著降低第37天血清皮质醇浓度（P<0.05）;各组肉品质差异不显著（P>0.05）;宰杀后各组pH45 min和pHult的差异不显著（P>0.05）。因此,环境富集和饲养密度能在一定程度上提高绵羊福利。     

Effect of dietary l-carnitine supplementation and energy level on oxidant/antioxidant balance in laying hens subjected to high stocking density

This study aimed to investigate the effect of l -carnitine and energy level and on oxidant/antioxidant balance in laying hens subjected to high stocking density. A total of 176, 32-week-old laying hens were assigned to eight groups with four replicates and hens in four groups were placed at the normal stocking densities of 500 cm²/hen (four hens per cage) and in the remaining four groups were placed at the high stocking densities of 287.5 cm²/hen (seven hens per cage). Hens received diets of high (2,850 kcal/kg ME) or normal (2,650 kcal/kg ME) energy which are supplemented with 0 or 200 mg/kg l -carnitine for 70 days. Results showed that exposure to high stocking density increased (p < .05) plasma malondialdehyde (MDA) and nitric oxide (NO) levels and decreased (p < .05) erythrocyte superoxide dismutase (SOD), catalase (CAT) and superoxide dismutase (GPx) activities. l -carnitine supplementation increased (p < .05) erythrocyte SOD, CAT and GPx activities, and decreased (p <.05) MDA and NO level in high stocking densities. The oxidan/antioxidan balance of birds was not influenced by increasing dietary energy level. The results of the present study indicate that the supplementation of l -carnitine to the birds subjected to high stocking density could effectively reverse the negative effects of high stocking density by improving oxidant/antioxidant balance. Therefore, l -carnitine supplementation at level of 200 mg/kg to diet may be as a favourable alternative to deal with oxidative stress caused by high stocking density in laying hens.