The production of short chain fatty acid and colonic development in weaning piglets

Weaning process widely affects the small intestinal structure and function in piglets, while the responses of large intestine to weaning stress are still obscure. The purpose of this study was to determine the developmental changes (i.e., short chain fatty acids (SCFAs) concentrations, growth parameters, crypt‐related indices and antioxidant capacity) in colon of piglet during weaning. Forty piglets were weaned at day 21 and euthanized to collect colonic tissues and digesta samples on day 0, 1, 3, 7 and 14 post‐weaning (n = 8). Piglet growth performance was improved (p < .001) on day 7 and 14 post‐weaning. The concentrations of acetate, propionate, butyrate, valerate, isobutyrate, isovalerate and total SCFAs were higher (p < .001) during the late post‐weaning period. The mRNA abundances of SCFAs transporters were greater (p < .001) on day 7 and 14. The absolute and relative weights, absolute length and perimeter of colon were greater (p < .001) on day 7 and 14. Similarly, post‐weaning increases (p < .001) in colonic crypt depth and Ki67 positive cells numbers per crypt were observed during the same period. Colonic crypt fission indices decreased (p < .01), while total crypt numbers increased (p < .001) on day 14 after weaning. Moreover, total SCFAs concentration was significantly associated with colonic growth parameters and Ki67 cells/crypt (p < .001). In addition, catalase content was decreased on day 3, 7, and 14, whereas, the concentrations of total superoxide dismutase (T‐SOD) and manganese‐containing superoxide dismutase (MnSOD) were higher (p < .05) on day 1 and 3 post‐weaning. These results showed that weaning process has a significant effect on colonic growth and development, which might be associated with the change of SCFAs concentrations in colon.     

Absence of three known benzimidazole resistance mutations in Trichostrongylus tenuis, a nematode parasite of avian hosts

Benzimidazole (BZ) resistance is widespread in nematode parasites of livestock, but very little is known about the levels of BZ resistance in parasites with avian hosts. We investigated BZ resistance in Trichostrongylus tenuis, a nematode parasite of red grouse, Lagopus lagopus scotica. BZ anthelmintics had been in use in this system for up to 15 years, yet existing phenotypic evidence for resistance was inconclusive. We screened 1530 individuals from 14 populations at the principal β-tubulin locus for BZ resistance (isotype 1, residue 200) and 940 of these at two further resistance sites (isotype 1, residue 167; isotype 2, residue 200). No BZ resistant genotypes were found. Alternative mechanisms may be responsible for BZ resistance in this system, or the method and timing of treatments may reduce selection pressure for BZ resistance by creating substantial refugia for susceptible genotypes.     

Seroprevalence and risk factors for influenza A viruses in pigs in Peninsular Malaysia

Following a series of H5N1 cases in chickens and birds in a few states in Malaysia, there was much interest in the influenza A viruses subtypes that circulate among the local pig populations. Pigs may act as a mixing vessel for avian and mammal influenza viruses, resulting in new reassorted viruses. This study investigated the presence of antibodies against influenza H1N1 and H3N2 viruses in pigs from Peninsular Malaysia using Herdcheck Swine Influenza H1N1 and H3N2 Antibody Test Kits. At the same time, the presence of influenza virus was examined from the nasal swabs of seropositive pigs by virus isolation and real time RT-PCR. The list of pig farms was obtained from the headquarters of the Department of Veterinary Services, Malaysia, and pig herds were selected randomly from six of 11 states in Peninsular Malaysia. A total of 727 serum and nasal swab samples were collected from 4- to 6-month-old pigs between May and August 2005. By ELISA, the seroprevalences of swine influenza H1N1 and H3N2 among pigs were 12.2% and 12.1% respectively. Seropositivity for either of the virus subtypes was detected in less than half of the 41 sampled farms (41.4%). Combination of both subtypes was detected in 4% of all pigs and in 22% of sampled farms. However, no virus or viral nucleic acid was detected from nasal samples. This study identified that the seropositivity of pigs to H1N1 and H3N2 based on ELISA was significantly associated with factors such as size of farm, importation or purchase of pigs, proximity of farm to other pig farms and the presence of mammalian pets within the farm.     

草本化栽培杂交桑在种茧育上的应用研究

本试验以杂交桑“沙2×伦109”为材料,以普通桑园的湖桑32号片叶育为对照,就草本化栽培杂交桑在种茧育上应用的可行性进行了探讨。结果表明,在配合施用叶面肥0.2％PGH-X的情况下,供试杂交桑在原蚕生长发育、茧质及制种成绩方面与对照区相近或持平,说明原蚕饲养采用草本化栽培杂交桑及条桑二回育形式具有可行性。使用叶面肥0.15％PGH-D可使原蚕5龄期经过延长,对家蚕生长发育表现一定调控作用。     

Catheters: a review of the selection, utilisation and complications of catheters for peripheral venous access

Intravenous catheters are used for the administration of medications and fluids and are an integral part of veterinary practice. The aim of catheter use is to optimise administration of medication and minimise complications such as thrombus formation, thrombophlebitis and sepsis. Catheters made from teflon are less flexible, less durable and stimulate more tissue reaction than polyurethane or silicon. However silicon catheters are more expensive and complicated to insert. Generally, for veterinary practice, the biostability and cost of polyurethane catheters make them preferable for short and long-term use. The smallest diameter catheter should be selected to minimise internal vessel wall contact and irritation without compromising medication delivery. The site of insertion varies with individual preference, vessel access and patient compliance. The jugular, cephalic, saphenous, ear, lateral thoracic and subcutaneous abdominal veins are accessible. Hair removal and a thorough aseptic skin preparation should be performed prior to catheter insertion. Daily maintenance is required to detect complications and maximise catheter longevity. Potential complications include thrombus formation, thromboembolism, bacterial colonisation and septicaemia, blood loss and air embolism. Permanent or transient skin dwelling bacteria are commonly isolated if sepsis occurs. The development of novel antiseptic and antibiotic impregnated catheters may reduce the complications associated with catheter infection in the future.     

立枯丝核菌侵染玉米的研究

 用获自水稻及玉米的立枯丝核菌(Rhizoctonia solani Khn) AG-11A接种玉米发生典型纹枯症状,其致病力显著强于AG-4。玉米拔节期,上位叶鞘抗性较强,抽雄及抽丝期抗性减弱,下位叶鞘无论在拔节期或抽雄、抽丝期,均较上位叶鞘感病。接种玉米后8小时,形成侵染垫及附着胞,从这些结构上形成侵入钉侵入,AG-4侵染上位叶鞘时,常以菌丝直接穿透表皮或从气孔侵入。在去掉菌体的叶鞘表面,发现有周边光滑或稍破损的侵入孔。接种后12小时,在叶鞘细胞中发现菌丝,它们在穿过细胞壁进入邻近细胞时,明显变细。接种后16小时,新生出的菌丝从气孔成丛出现。     

规模化猪场疫病传入的外部风险因素指标体系的初探

据实际调查,运用层次分析法,将疫病传入的各外界风险因素指标划分为目标层、准则层和分准则层三个层次。采用EXCEL软件进行数据统计,依次编辑各层次结构模型,构建各层次的判断矩阵和一致性检验。结果表明：猪场的管理措施、生物安全、场址是疫病传入的主要风险因素。据此确立了I级指标和II级指标,从而构建疫病传入的风险因素指标体系。     

搜爆训练中犬行为诊断

对犬在搜爆训练中的行为进行分析,可以正确判断犬在搜索中的工作状态,以便抓住根源纠正犬在训练中出现的问题,对提高带犬民警的指挥操作能力有着重要的意义.     

Heinz body anemia in a dog that had been sprayed with skunk musk

A 5-year-old pit bull-type dog was examined because of lethargy and black feces, and a presumptive diagnosis of methemoglobinemia was made on the basis of grossly visible brown discoloration of the mucous membranes and urine. Heinz body formation was seen on examination of blood smears, and severe anemia developed 3 days later. The dog did not have any history of exposure to toxins or drugs that have been associated with Heinz body formation. The only remarkable historical finding was that the dog had been wandering loose the day prior to initial examination and returned home smelling strongly of skunk spray. Skunk spray contains thiols and other compounds that are strong oxidizing agents. It was speculated that the methemoglobinemia and Heinz body anemia were a result of exposure to these compounds. Skunk interactions with dogs usually have malodorous but otherwise harmless results. However, findings in this dog suggest that more serious consequences may develop in isolated cases.     

对动物防疫体系建设的思考

近来,动物防疫体系建设越来越成为社会关注的热点,各地对动物防疫体系建设的力度不断加大,对其管理模式进行了一些有益探索。笔者认为必须在以下几个问题上提高认识。1充分肯定动物防疫体系的历史作用,提高动物防疫体系建设重要性的认识动物防疫体系在过去50多年中对支持畜牧业