Cold resistance and environmental temperature preference in diarrheic piglets

Piglets aged 12 to 72 h in which diarrhea had been induced by enteric Escherichia coli infection or sucrose gavage were studied with respect to cold resistance and thermal-circulation index in a 90-min test in a 6 C environment (Exp. 1) and free-choice environmental-temperature preference during a 60-min test in a 24 to 44 C thermocline (Exp. 2). In Exp. 1, diarrhea lowered the piglet's ability to maintain body temperature during the cold test. Also, diarrheic piglets tended to have lower thermal circulation index values at the end of the cold test, indicative of a greater vasoconstrictive response to the cold environment. In Exp. 2, mean preferred environmental temperatures were 35.7, 34.9 and 34.5 C, respectively, for piglets in sham-control, E. coli-infected and sucrose-gavaged groups. For reason(s) still unknown, diarrheic piglets did not choose to locate themselves in a warmer niche than did normal piglets; in fact, they did the opposite. Results of the two experiments indicate that diarrheic neonatal piglets need even more attention and care in terms of the thermal environment than do healthy ones.     

黄芩苷治疗仔猪腹泻的作用机制

通过黄芩苷治疗试验、体外抑菌试验、炎性渗出抑制试验以及炎性细胞因子检测,来探讨黄芩苷治疗仔猪腹泻的作用及可能机制。结果表明,低、中剂量黄芩苷的治愈率显著高于新霉素组、新黄组和高剂量的黄芩苷(P0.05,P0.01)。各质量浓度的黄芩苷体外抑菌效果极显著低于2%新霉素和新黄组(P0.01)。黄芩苷各组腹腔液伊文思蓝含量与地塞米松组均没有差异(P0.05),中、高剂量组与对照组也没有差异。各组血清IL-1β含量均显著高于对照组(P0.01,P0.05),各组TNF-а含量亦均上升,但各剂量黄芩苷组的IL-1β、TNF-а含量均低于腹泻组,尤其低剂量组下降显著(P0.05,P0.01)。以上结果揭示黄芩苷能够抑制炎性渗出(高剂量最强)、降低致炎细胞因子的释放(低剂量最强)是其发挥治疗作用的机制之一。     

Body weight of newborn and suckling piglets affects their intestinal gene expression

Modern hyperprolific sows must deal with large litters (16–20 piglets) which reduce piglet birthweight with a concomitant increase in the proportion of small and intrauterine growth retarded piglets. However, larger litters do not only have a greater variation of piglet weights, but also a greater variation in colostrum and milk consumption within the litter. To further understand the impact that body weight has on piglets, the present study aimed to evaluate the degree of physiological weakness of the smallest piglets at birth and during the suckling period (20 d) compared to their middle-weight littermates through their jejunal gene expression. At birth, light piglets showed a downregulation of genes related to immune response (FAXDC2, HSPB1, PPARGC1α), antioxidant enzymes (SOD2m), digestive enzymes (ANPEP, IDO1, SI), and nutrient transporter (SLC39A4) (P < 0.05) but also a tendency for a higher mRNA expression of GBP1 (inflammatory regulator) and HSD11β1 (stress hormone) genes compared to their heavier littermates (P < 0.10). Excluding HSD11β1 gene, all these intestinal gene expression differences initially observed at birth between light and middle-weight piglets were stabilized at the end of the suckling period, when others appeared. Genes involved in barrier function (CLDN1), pro-inflammatory response (CXCL2, IL6, IDO1), and stress hormone signaling (HSD11β1) over-expressed compared to their middle-weight littermates (P < 0.05). In conclusion, at birth and at the end of suckling period, light body weight piglets seem to have a compromised gene expression and therefore impaired nutrient absorption, immune and stress responses compared to their heavier littermates.     

Body weight and body condition of breeding rabbits in commercial units

Live BW and BCS data were collected from 2,775 breeding rabbits (644 males and 2,131 females) of 34 genetic types and sorted according to their specialization (maternal, paternal, and others). Data were gathered on 66 visits to 43 commercial farms in Spain between 2009 and 2011. Mean BW was 4.72 kg (range of 2.87 to 8.13 kg, with a median BW of 4.60 kg) and mean BCS was 4.6 (range of 1.0 to 9.0, with a median BCS of 5.0). females had heavier (P < 0.05) BW than males and paternal lines of rabbits had greater (P < 0.05) BW than maternal lines and other breeds/lines not selected for meat production. Between 69.3% and 75.4% of the rabbits were deemed healthy by a veterinarian and, as expected, healthy rabbits were heavier (P < 0.05) than sick rabbits diagnosed with rhinitis, mastitis, sore hocks, and several other diseases. Among purebred, maternal lines of rabbits, Hyplus GD24, UPV A, and UPV V were heavier (P < 0.05) than hyplus GD14 and Hyla HL-D lines, and line UPV R had the greatest (P < 0.05) BW among the purebred, paternal lines. Additionally, A×H, A×V, PS19, and P×A crossbreds had greater (P < 0.05) BW than HE-C×D, HL-C×D, H×V, LP×V, and V×P crossbreds among the maternal lines, whereas HE-SL were the heaviest (P < 0.05) crossbred paternal line of rabbits. Additionally, females received greater (P < 0.05) BCS than males and BCS were greater (P < 0.05) in healthy than sick rabbits. Moreover, maternal lines had smaller (P < 0.05) BCS than either paternal lines or other lines/breeds not selected for meat production. Results also indicated a moderate relationship between BCS and BW (r = 0.32), with a 1-point change in BCS equivalent to an ~ 245-g change in BW. results from this study can be used as baseline figures for breeding rabbits in spain and are essential factors in several decisions concerning housing, feeding, reproduction, health, and welfare of breeding rabbits.     

仔猪腹泻源大肠杆菌耐药性调查及耐药基因检测

对泰州地区分离的仔猪腹泻源大肠杆菌的耐药性及其携带的相关耐药基因情况进行检测,为养殖场今后合理用药提供科学依据。采用微量肉汤稀释法对分离的49株大肠杆菌进行8种抗菌药物的药敏试验;采用PCR方法对多黏菌素耐药基因mcr-1及超广谱β-内酰胺酶(ESBL)耐药基因blaCTX-M、blaSHV和blaTEM进行检测。药敏试验结果显示:大肠杆菌对氯霉素、氟苯尼考、氨苄西林、四环素、庆大霉素和恩诺沙星等的耐药率分别达到100%、97.96%、95.92%、89.80%、59.18%和51.02%;而对多黏菌素E和头孢噻呋的耐药率也达到44.90%和32.65%。进一步耐药基因检测结果显示:ESBL耐药基因中blaCTX-M的检出率最高,达到12.24%(6/49);其次为blaSHV,8.16%(4/49);有一株大肠杆菌携带blaTEM基因。其中一株同时携带blaCTX-M和blaSHV。多黏菌素耐药基因mcr-1的检出率达到30.61%(15/49),其中4株同时携带blaCTX-M基因。泰州地区分离大肠杆菌耐药情况和多重耐药现象较为严重,多黏菌素耐药基因mcr-1及ESBL耐药基因blaCTX-M、blaSHV和blaTEM的广泛分布表明这些耐药基因存在快速传播的风险。因此,有必要加强猪场细菌耐药性监测。     

仔猪腹泻源大肠杆菌的PCR快速检测

仔猪腹泻是危害养猪业的重要疾病,尽管导致仔猪腹泻的原因非常复杂,但大肠杆菌是其主要病原已经明确.本研究根据GenBank登录的肠毒素ST1、ST2、LT1以及耶尔森氏菌强毒力岛(HPI)的基因序列分别设计特异性引物,建立了检测相应毒力因子的PCR方法.通过对已知毒力型参考菌株的扩增,证明了所建立的PCR方法能够特异鉴定产肠毒素大肠杆菌(ETEC)和HPI+大肠杆菌.采集临床110例仔猪腹泻病例的直肠棉拭子样品.接种LB肉汤于37℃增菌培养4 h～6 h后,运用所建立的PCR方法进行检测,结果表明有55例(50%)为HPI+大肠杆菌感染,9例(8.18%)为HPI+大肠杆菌与ETEC混合感染,7例(6.37%)为ETEC感染.通过与细菌分离后鉴定的比较,证明该诊断方法具有速度快、检出率高的特点,适合于临床活体检测.     

Escherichia coli strains isolated from diarrheic piglets in the Province of Quebec.

During 1972 to 1974, 112 Escherichia coli strains isolated from diarrheic piglets were recieved from different parts of the Province of Quebec, Canada. Fifty-six strains elicited a positive gut loop response in three week old piglets and were then considered as Moon's class 1 enteropathogens, while four of the 56 remaining strains reacted only in ten day old piglets and were classified as class 2 enteropathogens. Forty-eight strains produced both a heat-labile and a heat-stable enterotoxin, while 12 isolates which included the four class 2 enteropathogens produced only a heat-stable enterotoxin. Fifty-one enterotoxigenic strains could be serogrouped using OK antisera against E. coli strains commonly associated with colibacillosis in piglets. The most common serogroups encountered were O157: K "V17"; 88a,c, O149:K91; 88a.c. O157:K"V1c, O149:K91; 88a.c, O157:K"V17"; 88 a,c or a,b and O45:K"E5"; 88a,c. No significant difference was observed in the fermentation patterns, antibiotic susceptibility, colicin production, production of a filterable hemolysin and transferable tetracycline resistance between the enterotoxigenic and the nonenterotoxigenic strains.     

文山高峰牛母牛体重与体尺的相关性分析

[目的]为了探究文山高峰牛母牛的体重与体尺性状的相关性,建立文山高峰牛母牛体重与体尺性状之间的最优回归方程,为文山高峰牛遗传参数的选择提供参考,并为牛品种的选育工作供理论依据。[方法]试验随机选取20头30月龄文山高峰牛母牛,测量体重(Y)、体高(X₁)、十字部高(X₂)、体斜长(X₃)、胸围(X₄)、腹围(X₅)、管围(X₆),然后计算体重和体尺性状的变异程度并进行相关性分析、通径分析及逐步回归分析以建立其体重与体尺性状之间的最优回归方程。[结果]文山高峰牛母牛的体重的变异系数最大(9.42%);体重与6项体尺性状均呈极显著正相关(P<0.01),腹围和体重间的相关系数最大(0.924);通径分析结果显示,腹围对体重的直接作用较大,十字部高、体斜长、胸围对体重的间接作用大。[结论]腹围、十字部高、体斜长是影响体重的最主要性状,通过逐步回归分析构建的文山高峰牛母牛体重与体尺之间的最优回归方程为Y=-648.762+0.639X₅...     

免疫球蛋白制剂对仔猪增重和某些血液指标的影响

本试验选用新生大白仔猪130头，随机分为5组，每组26头。A组为对照组，其余各组饲喂不同剂量的免疫球蛋白制剂。观察对仔猪断奶时的增重和10、20日龄血清总蛋白、血红蛋白含量的影响。结果表明：饲喂10m1(B组)免疫球蛋白制剂的仔猪，其20日龄血清总蛋白含量及10、20日龄血红蛋白含量均极显著高于对照组(P＜0．01)；饲喂10m12次(C组)的仔猪，其10、20日龄血红蛋白含量显著高于对照组(P＜0．05)；B、C组断奶时增重均极显著高于对照组(P＜0．01)。结果显示，10m1免疫球蛋白制剂(48．4mg／ml）为最适添加剂量。     

Abdominal fat weight and thickness as predictors of total body fat in broilers

In two experiments broilers of both sexes from two strains were reared to 16 weeks of age to determine how total body fat could be estimated and predicted from some carcase traits. In the first experiment, age, carcase weight and abdominal fat thickness were found to be significant factors in the prediction of total body fat weight estimated from abdominal fat weight. In the second experiment abdominal fat weight was the best predictor of total body fat weight, obtained by ether extraction of the minced whole carcase. Inclusion of abdominal fat weight in the prediction equation after carcase weight and abdominal fat thickness significantly improved the regression. If the carcase cannot be weighed and abdominal fat weight is not available, because of the more laborious nature of its determination, then the measurement of abdominal fat thickness can be useful in predicting the total body fat content.     

健康与腹泻仔猪源A型产气荚膜梭菌的多位点序列分型

A型产气荚膜梭菌(CpA)存在于健康仔猪肠道,同时也是仔猪肠毒血症的关键病原.为研究两者的差异,本试验在江西省4个地区采集健康和腹泻仔猪粪便样本分离得到CpA,通过16S rRNA鉴定所有CpA分离株,并通过多重PCR确定分离株的毒素分型.采用MLST多位点序列分型技术对选取的24株CpA(腹泻或健康来源CpA各12株...     

Genotypic prevalence of F4 variants (ab, ac, and ad) in Escherichia coli isolated from diarrheic piglets in Korea.

A total of 812 Escherichia coli strains isolated from diarrheic piglets were tested for the presence of the F4 (K88) variant (ab, ac and ad) gene by the polymerase chain reaction. Forty four (5.4%) of the 812 E. coli strains carried genes for F4. Among the 44 isolates known to carry genes for F4, 42 (96%) isolates contained genes for F4ac and 2 (4%) isolates contained genes for F4ab. None of the E. coli strains carried genes for F4ad. Our data show that F4ac is the predominant F4 variant associated with diarrhea in piglets in Korea.