Taste aversion learning in horses

The ability of ponies to learn to avoid a relatively novel food associated with illness was tested in three situations: when illness occurred immediately after consuming a feed; when illness occurred 30 min after consuming a feed; and when illness was contingent upon eating one of three feeds offered simultaneously. Apomorphine was used to produce illness. The feeds associated with illness were corn, alfalfa pellets, sweet feed and a complete pelleted feed. The ponies learned to avoid all the fees except the complete feed when apomorphine injection immediately followed consumption of the feed. However, the ponies did not learn to avoid a feed if apomorphine was delayed 30 min after feed consumption. They could learn to avoid alfalfa pellets, but not corn, when these feeds were presented with the familiar "safe foods," oats and soybean meal. Ponies apparently are able to learn a taste aversion, but there were constraints on this learning ability. Under the conditions of this study, they did not learn to avoid a food that made them sick long after consumption of the food, and they had more difficulty learning to avoid highly palatable feeds.     

Gastrointestinal zygomycosis in suckling pigs

Gastrointestinal zygomycosis was diagnosed in 3 suckling pigs (10, 14, and 28 days old) with diarrhea that was unresponsive to treatment with broad-spectrum antibiotics. The 3 pigs were from separate farms, and littermates of the 3 pigs with similar clinical signs had died. At necropsy, 2 of the 3 pigs had catarrhal to fibrinonecrotic gastroenteritis, and the third pig had hemorrhagic gastritis without intestinal lesions. Microscopically, transmural necrosis of the stomach and intestines was associated with marked inflammatory cell infiltration and thrombosis and vasculitis of vessels of the lamina propria and submucosa. Numerous broad, irregularly branching, nonseptate, mucoraceous fungi were seen in the lumens of blood vessels and in the necrotic mucosa and submucosa.     

三种微生态制剂对哺乳母猪、哺乳仔猪及保育猪的应用效果研究

本研究通过对长×大二元杂交哺乳母猪、皮×杜×长×大四元杂交哺乳仔猪、保育猪分别使用利生菌王、益牧宝、方便菌3种不同微生态制剂进行效果试验,结果表明:利生菌王能显著提高哺乳母猪、哺乳仔猪的生长性能,益牧宝对保育猪的生长性能的提高效益较好。     

Mild transmissible gastroenteritis in pigs suckling vaccinated sows

A strain of transmissible gastroenteritis (TGE) virus of low virulence was isolated from 14-day-old pigs suckling sows vaccinated with an attenuated TGE vaccine. Diarrhea developed in suckling pigs approximately 14 days after farrowing in 4 farrowings; however, none of these pigs died from diarrhea. Diarrhea ceased after the 4th farrowing, when vaccination of sows was discontinued. Experimentally, both the field isolate and the vaccine strain were infective and in some instances lethal for 2-day-old pigs exposed orally; however, neither strain was as virulent as the Purdue strain.     

早期断奶仔猪蛋白质营养研究进展

早期断奶最大障碍在于仔猪的消化机能不健全而对饲料的要求特别高。本文结合早期断奶仔猪消化生理特点,介绍了仔猪断奶后氨基酸营养的需要和各种蛋白质饲料原料的营养价值,为调制由母乳过渡到仔猪日粮且不影响仔猪生长率的蛋白质饲粮提供参考。     

环磷酰胺对断奶仔猪免疫功能的影响

本试验旨在探讨环磷酰胺(CY)对断奶仔猪免疫功能的影响。选取12头(28±3)d的杜×长×大断奶仔猪,随机分为对照组和CY组。第1天和第7天,给CY组仔猪注射50mg/kg BW的CY,对照组仔猪注射等量的生理盐水;第7天和第14天,前腔静脉采血待测;第14天,测定迟发型超敏反应。结果表明:(1)CY可降低第7天断奶仔猪的中性粒细胞数量(P0.1)及第14天白细胞、淋巴细胞、中性粒细胞(P0.05)和单核细胞数量(P0.1);(2)CY可降低第14天牛血清白蛋白抗体水平(P0.05);(3)CY可降低第7天干扰素-γ水平(P0.05)。本研究结果表明,CY可抑制断奶仔猪的免疫功能。     

First-pass splanchnic metabolism of dietary cysteine in weanling pigs

Cysteine is a semi-indispensable AA in neonates and is synthesized from the indispensable AA, methionine, by transsulfuration. We previously showed that the gastrointestinal tract (GIT) is a metabolically important site of methionine transsulfuration to cysteine, yet the metabolic fate of dietary cysteine in the GIT has not been established. Cysteine use by gut epithelial cells may play an important role for maintenance of glutathione synthesis and cellular redox function. Our aim was to quantify the extent of gastrointestinal first-pass cysteine metabolism in young pigs. Four-week-old weanling pigs (n = 10) were fed a liquid milk-replacer diet and given an intragastric and intravenous [1-(13)C]cysteine infusion on 2 separate days in a crossover design. Arterial and portal blood samples were collected for cysteine isotopic enrichment by gas chromatography-mass spectrometry and for (13)CO(2) enrichment by isotope ratio mass spectrometry. Our results indicated that dietary cysteine is metabolized during its first-pass splanchnic metabolism, accounting for about 40% of dietary cysteine intake. We also showed that intestinal absorption was the major metabolic fate of dietary cysteine, representing about 75% of intake, indicating that the GIT utilizes 25% of the dietary cysteine intake. Thus, utilization by the GIT represents about one-half (approximately 53%) of the first-pass, splanchnic uptake of dietary cysteine. Moreover, a substantial proportion of dietary splanchnic cysteine metabolism was consumed by the GIT via nonoxidative pathways. We conclude that the gut utilizes 25% of the dietary cysteine intake and that synthesis of mucosal epithelial proteins, such as glutathione and mucin, are a major nonoxidative metabolic fate for cysteine.     

Social hierarchy in suckling and fattening pigs: A review

This brief account of recent work on social hierarchy and its relation to production and disease in the domesticated pig covers the development of the teat order and its influence (if any) on the dominance hierarchy, the mechanisms by which previously unacquainted pigs sort themselves out into a social order, the leadership hierarchy, the factors affecting the stability of the dominance hierarchy, and the way in which a breakdown of the normal social order may contribute to outbreaks of aggression (e.g. tail-biting and cannibalism) within previously contented groups of pigs. A plea is made for further work on some of these important behavioural areas.     

酵母培养物对断奶仔猪的饲喂效果试验

试验以137头21日龄断奶仔猪为对照组,133头21日龄断奶仔猪为试验组,分别饲喂添加了0%和0.25%酵母培养物的断奶仔猪全价日粮。结果发现:①试验组和对照组仔猪21日龄的断奶平均个体重差异不显著(6.49kg和6.20kg,P=0.5918),而仔猪42日龄时的平均个体重差异显著(13.33kg和11.97kg,P=0.020),仔猪平均个体重试验组比对照组每头增加1.07kg;②仔猪27日龄转舍后,前6d的仔猪平均采食量试验组要显著高于对照组(0.35kg和0.24kg,P=0.039);③对照组有4头仔猪有轻度腹泻,试验组无腹泻发生。