Sudden death caused by stomach dilatation in swine

Related to the feeding 71 sudden deaths occurred in a hybrid breeding unit of 600 sows during a period of 3 years. Post mortem examination showed acute gastric dilatation as the cause of death. The retrospective survey showed that all sows were the offspring of the same landrace boar. Therefore, the deaths are supposed to be related to excess excitement coinciding with a hereditary vegetative lability.     

Does feeding time affect fish welfare?

Increased aquaculture production has raised concerns about managing protocols to safeguard the welfare of farmed fish, as consumers demand responsible aquaculture practices to provide ‘welfare friendly’ products. Feeding is one of the largest production cost in a fish farm and can be one of the biggest stressors for fish. Under farming conditions, fish are challenged with artificial diets and feeding regimes, and inadequate feeding conditions cause stress, alteration of normal behavioural patterns, poor performance and eventually diseases and death, which are by no means acceptable neither economically nor ethically. This review aims to highlight the impact of feeding rhythms and feeding time upon physiological and behavioural welfare indicators, which show circadian rhythms as well. Therefore, all these variables should be considered when designing feeding strategies in farming conditions and assessing the welfare state of cultured fish.     

Effect of an antepartum administration of prednisolone on the early postnatal mortality of piglets in relation to the body condition of the sow

In a single large pig production unit of 6000 breeding sows, 2 groups of 100 sows each were formed at random on the 110th day of pregnancy. Each group was evaluated and divided according to body condition in three subgroups. The groups were treated as follows: Group 1 received a 100 mg single intramuscular dose of prednisolone on the 113th day of pregnancy. Group 2 received a 3 ml single intramuscular dose of physiologic NaCl solution on the 113th day of pregnancy. The parameter "piglets born alive" and the parameter "early postnatal death" were evaluated. The parameter "piglets born alive" shows no significant difference between group 1 and 2. Group 1 showed significantly less early postnatal death compared to group 2. In contrast to other studies, the fat sows of the subgroups 5 in groups 1 and 2 showed no significant difference.     

Analysis of several years of breeding hygiene work in swine

An analysis of disturbances in sow fertility in breeding units in regard to the clinical appearance, the cause and pathology as well as the possibilities of prophylaxis, was conducted. The important reductions or disturbances in fertility are: --An- and subestrous of gilts --disturbances in ovulation, silent estrous as well as prolonged resting phases of old sows --cyst development and subsequent anestrous of old sows --persisting lactation anestrous. The main source of disturbance in the fertility of the sows was found to be the nutrition not adequately adapted to physiological needs especially in advanced pregnancy and other stress situations. The correction of the mentioned causes through management is the most important measure in prophylaxis.     

Pathological indicators in sows relevant to animal welfare in modern housing systems

Methods and problems are discussed evaluating pathological indicators potentially related to animal welfare in modern husbandry systems of brood sows. A variety of interrelationships of diseases and genetic dispositions concerning the locomotive and cardiovascular system interferes with the required forensic evidence between individual sickness and housing and/or neglected care. There are no defined pathological processes indicating disproportionate husbandry as well as insufficient ability of physical exercise. Highly restricted possibilities to move caused by modern housing may result in pathologically manifest alterations. Technopathic diseases (induced by housing systems) may be prevented by enhanced care concerning the health control of animals and the functioning of the technical equipment as well as by appropriate prophylaxis. Farmers and veterinary surgeons should co-operate for the needs of animal welfare. One of the resulting conclusions is to plan for and to provide more labour for specific care necessary to maintain animal welfare. One should consider such management calculations with major precaution in which the size of working units relative to manpower gets increasingly maximized.     

No apparent differences in intestinal histology of channel catfish (Ictalurus punctatus) fed heat-treated and non-heat-treated raw soybean meal

The histopathologic effects of feeding heat‐treated soybean meal to fingerling channel catfish (Ictalurus punctatus) were studied. Fish were fed one of six diets: a diet containing 450 g kg^?1 commercial soybean meal (CSBM), or diets with the CSBM replaced by non‐heat‐treated raw soybean meal (RSBM0), or RSBM heated at 130 °C for 5 min (RSBM5), 10 min (RSBM10), 20 min (RSBM20) or 40 min (RSBM40). After 10 weeks, tissue samples were taken from the stomach, proximal intestine, distal intestine, liver, pancreas and spleen from fish in each group for histologic examination. Mild necrotic lesions were found in the gastric glands, pancreas and liver of fish in all the groups (treatment and control groups). Hepatic glycogen deposition was also observed in all the groups, and the spleen samples exhibited considerable brownish‐black pigment deposition around the splenic corpuscles and diffuse mild‐to‐moderate congestion in all of the groups. Generally, these histologic effects appeared to be equivocal between all of the groups, and no abnormalities were noted in the proximal or distal intestine. These findings suggest that feeding channel catfish a diet containing 450 g kg^?1 non‐heat‐treated RSBM did not cause severe histologic changes associated with soybean meal anti‐nutritional factors as have been reported in salmonids.     

Nocturnal and diurnal feeding by Galaxias auratus, a lentic galaxiid fish

Abstract –  We examined the diel feeding pattern, gastric evacuation and daily ration of a lentic, endemic Tasmanian galaxiid fish, Galaxias auratus . Analysis of stomach contents and consumption estimates based on collections of fish every 3 h over three 24-h periods in summer 2002/2003 revealed that feeding always occurred during both day and night, with no obvious peaks. We also estimated the gastric evacuation rate of G. auratus in a laboratory experiment using the two prey species found to be dominant in stomachs of field-sampled fish. The relationship was best described by an exponential model, with rate parameters ( R ) of 0.104 and 0.081 for the evacuation of the amphipod, Austrochiltonia australis , and the cladoceran, Daphnia carinata , at water temperatures of 11.5 and 16.5 °C, respectively. Daily ration of G. auratus in summer was estimated to be approximately 3% (dry body weight) using the models of Elliot & Persson and Eggers. Galaxias auratus appears to be unusual in that its feeding pattern cannot be classified as nocturnal, diurnal or crepuscular, but its gastric evacuation and daily ration estimates are still similar to other comparable Northern Hemisphere freshwater fishes.     

Controlled hatchery production of Clarias gariepinus (Burchell 1822): an estimate of maximum daily feed intake of C. gariepinus larvae

Abstract. The satiation time, stomach capacity, gastric evacuation rate and return of appetite were investigated in Clarias gariepinus larvae. The evacuation of food from the stomach was described by the exponential model. Gastric evacution was found to be inversely related to return of appetite. Both satiation time and feed intake as a % of body weight were found to increase rapidly over the first few days of larval feeding, after which they remained constant. A simple model is proposed for the estimation of maximum feed intake in relation to feeding scheduled and feeding frequency for Clarias gariepinus larvae.     

The importance of exogenous factors on the composition of the urine of breeding sows

The influence of protein content in feed, of reduced and increased water-intake, of different hygienic situations and of antibiotic feed-medication on urine contents was controlled in healthy and cystitis diseased sows. It could be shown, that the urinary quality of healthy and ill sows was influenced in the same direction by exogenous factors. The amount of water-intake shows the greatest influence. Its rinsing effect on the quantity of relevant parameters of the urine examination (bacterial count, protein content, cell content) can induce misleading findings. Therefore the evaluation of the urinary status should be completed by anamnestic information, especially concerning increased or reduced water-intake.     

Ontogenetic development of digestive functionality in golden pompano Trachinotus ovatus (Linnaeus 1758)

Ontogenetic development of the digestive system in golden pompano (Trachinotus ovatus, Linnaeus 1758) larvae was histologically and enzymatically studied from hatch to 32 day post-hatch (DPH). The development of digestive system in golden pompano can be divided into three phases: phase I starting from hatching and ending at the onset of exogenous feeding; phase II starting from first feeding (3 DPH) and finishing at the formation of gastric glands; and phase III starting from the appearance of gastric glands on 15 DPH and continuing onward. The specific activities of trypsin, amylase, and lipase increased sharply from the onset of first feeding to 5–7 DPH, followed by irregular fluctuations. Toward the end of this study, the specific activities of trypsin and amylase showed a declining trend, while the lipase activity remained at similar levels as it was at 5 DPH. The specific activity of pepsin was first detected on 15 DPH and increased with fish age. The dynamics of digestive enzymes corresponded to the structural development of the digestive system. The enzyme activities tend to be stable after the formation of the gastric glands in fish stomach on 15 DPH. The composition of digestive enzymes in larval pompano indicates that fish are able to digest protein, lipid and carbohydrate at early developmental stages. Weaning of larval pompano is recommended from 15 DPH onward. Results of the present study lead to a better understanding of the ontogeny of golden pompano during the larval stage and provide a guide to feeding and weaning of this economically important fish in hatcheries.     

Feeding and growth of glass eels, Anguilla anguilla L.: the effect of feeding stimulants on feed intake, energy metabolism and growth

Abstract. Two experiments were conducted in which glass eels, Anguilla anguilla L., were fed with six different diets. Two natural diets, cod roe and minced bovine spleen, and four artificial diets, an unflavoured trout fry crumble and three trout fry crumble diets with added feeding stimulants, were used. The feeding stimulants tested were cod roe extract, spleen extract and a mixture of synthetic L-amino acids. In the first experiment the glass eels were fed at a restricted feeding level and in the second experiment at an ad libitum feeding level. The intake of metabolizable energy (ME) was determined as the sum of retained energy and heat production. Metabolizability of the diets decreased with increasing feeding level and was 75-95% for cod roe, 35-50% for spleen and 40-60% for the artificial diets. Since utilization of ME for maintenance and growth was not affected by feeding level and diet, differences in growth rates could be explained by differences in ME intake. Group ME intake in turn was determined by the fraction of the fish which were actually eating. The uniform feeding response of the glass eels fed the natural diets resulted in the highest ad libitum ME intake (80-90 kJ/kg^0.8/day) and growth rate (4-4-4-9g/kg^0.8/day). Addition of feeding stimulants significantly increased the ad libitum ME intake of the artificial diets from 45 kJ/kg^0.8/day to 50-60 kJ/kg^0.8/day, which resulted in an increase in growth rate from 1·3 g/kg^0.8/day to 24 g/kg^0.8/day.     

Diel feeding pattern and ration of two sizes of silver barb, Puntius gonionotus Bleeker, in a nursery pond and ricefield

The diel feeding pattern, electivity and ration of 4.5-6.9 and 11.5-13.6 cm (total length) silver barb, Puntius gonionotus Bleeker, were investigated along with water quality characteristics in a nursery pond and a ricefield in Bangladesh. Small fish had two peaks (0900-1200 h and 1500-1800 h) in feeding activity in the pond but only one in the ricefield at 1500 h. Feeding at high levels went on throughout the day and on moonlit nights for small fish, and their diet was dominated in both environments by aquatic macrophytes as well as Microcystis, Spirogyra, Oedogonium and Cladophora, rotifers, crustaceans and insects. Large fish fed at low levels, had a single feeding peak during midday in the pond but no clear feeding peak in the ricefield. Large fish consumed macrophytes as well as Microcystis, Anabaena, Spirogyra and Cladophora, and crustaceans (in the pond) or molluscs (in the ricefield). Overall electivity was negative for microalgae. Zooplankton were avoided by large fish in the ricefield. The gastric evacuation time was 1-5 h at 27.5-34.0°C. Daily rations for small and large fish were estimated to be 1.4% and 0.3% of body weight in the pond and 1.1% and 0.6% in the ricefield. Improved fish yields may be achieved by stocking small P. gonionotus where the available food resources include important amounts of zooplankton, and by allowing aquatic macrophytes and weeds to grow in the ricefield or pond after stocking, such that the growing fish can feed increasingly on these.     

黄条鰤幼鱼胃排空特征、消化酶活性及摄食调控基因表达

为阐明黄条鰤幼鱼摄食消化特性，构建最佳胃排空数学模型，确立最适摄食投喂间隔，实验检测了黄条鰤幼鱼[(63.96±5.63) g]胃排空过程中内容物质量、肝脏和肠道中消化酶活性变化，分析了垂体中摄食调控相关基因的表达，比较了线性模型、平方根模型、立方模型3种数学模型对胃排空曲线的拟合程度。结果显示，黄条鰤在摄食后瞬时胃内容物湿重呈阶段性降低，18 h后降为0，属于直线下降型胃排空类型。胃排空过程中，肝脏淀粉酶、脂肪酶和糜蛋白酶活性呈先上升后下降、随后又上升接着下降的“M”型变化趋势，淀粉酶活性在摄食后0～6 h显著上升，脂肪酶和糜蛋白酶活性在0～9 h显著上升。三种酶活性在9～12 h均呈显著下降趋势，在15～18 h显著上升，且在18 h活性达到最高；肠道中的淀粉酶在0～6 h显著上升，随后下降，9～12 h呈上升趋势，12 h活性达到最高，随后逐渐下降，其脂肪酶和糜蛋白酶活性则是在摄食后0～12 h显著上升，12 h活性达到最高，随后逐渐下降。神经肽Y (npy)和食欲素(ore) mRNA表达水平呈先上升后下降趋势，npy在摄食后12～15 h内表达水平显著上升，ore在9～15 ...     

Evidence that <Emphasis Type="Italic">ghrelin</Emphasis> may be associated with the food intake of gibel carp (<Emphasis Type="Italic">Carassius auratus gibelio</Emphasis>)

Ghrelin, a non-amidated peptide hormone, is a potent anorectic neuropeptide implicated in feeding regulation in mammals and non-mammalian vertebrates. However, the involvement of ghrelin in the feeding behavior of teleosts has not been well understood. To better understand the role of ghrelin in the regulation of appetite in fish, in this study, we cloned the cDNAs encoding ghrelin and investigated their mRNA distributions in gibel carp tissues. We also assessed the effects of different nutritional status on ghrelin mRNA abundance. Ghrelin mRNAs were ubiquitously expressed in ten tissues (intestine, liver, brain, mesonephron, head kidney, spleen, skin, heart, muscle, gill and pituitary gland), and relatively high expression levels were detected in the gut. Postprandial studies analysis revealed a significant postprandial decrease in ghrelin mRNA expression in the gut (1 and 3 h after the regular feeding time). In addition, ghrelin mRNA expression in the gut significantly increased at day 7 after fasting and declined sharply after refeeding, which suggested that ghrelin might be involved in the regulation of appetite in gibel carp. Overall, our result provides basis for further investigation into the regulation of feeding in gibel carp.     

南沙岛礁周围水域主要鱼类食物网

在南沙岛礁周围水域收集了43种主要鱼类,共940个胃含物,根据对它们的食性分析,并依其食料生物的生态类群以及消化器官特点,一般可划分为浮游生物食性、底栖动物食性、游泳动物食性、浮游生物兼底栖动物食性、底栖动物兼游泳动物食性等5种食性类型。根据食物网中各营养级的相互关系,初步划分为4个营养级,即初级生产者(海洋植物)、草食性动物和杂食性动物、低级肉食性动物和中级肉食性动物、高级肉食性动物。并根据这些营养级的划分,南沙岛礁周围水域43种主要鱼类可分低级肉食性鱼类,中级肉性鱼类和高级肉食性鱼类,它们的比为28105。灰裸顶鲷是南沙岛礁周围水域三重剌网举足轻重的捕捞对象,从食物网的观点出发,应加强灰裸顶鲷幼鱼期敌害鱼和其竞食者的捕捞,为低级肉食性经济鱼类除害,灰裸顶鲷就有可能增加资源量。     

云龙石斑鱼胃排空特征和摄食消化特性研究

为阐明养殖新品种云龙石斑鱼(Epinephelus moara♀×E.lanceolatus♂)摄食胃排空特征和消化酶活性变化规律,本研究检测了体重为(680.35±39.84)g云龙石斑鱼摄食后胃内容物百分比,比较了线性模型、平方根模型和立方模型对胃排空曲线的拟合程度,分析了云龙石斑鱼摄食后血清中葡萄糖、皮质醇含量和肝脏消化酶活性变化,并对胃排空率与消化酶进行了相关性分析。结果发现,云龙石斑鱼摄食后,胃排空率呈典型的先慢后快再慢的消化类型。3种模型均能拟合云龙石斑鱼的胃排空数据,其中,立方模型拟合效果最佳。由立方模型可知,云龙石斑鱼胃80%排空(食欲基本恢复)时间为9.5 h,100%排空(食欲完全恢复)约为14.8 h。血清中葡萄糖、皮质醇含量及肝脏中消化酶(淀粉酶、糜蛋白酶和脂肪酶)活性在摄食胃排空过程中均呈先升高后降低的趋势。摄食后,血清中皮质醇、葡萄糖含量和肝脏内消化酶活性逐渐升高,0~3 h上升速率较慢,3~6 h内呈急剧上升的变化趋势,且在摄食后6 h,血清中皮质醇、葡萄糖含量和肝脏内消化酶活性达到最高(P<0.05),之后呈显著下降趋势,云龙石斑鱼瞬时排空速率与消化酶活性呈正相关(P<0.05)。综上,基于云龙石斑鱼胃排空特征和摄食消化特性,结合生产实践,在食欲基本恢复后开始投喂,投喂间隔为10 h左右,每日投喂2次,效果最佳。     

Development of the digestive system in dusky kob,Argyrosomus japonicus,larvae

In order to contribute to the development of larval rearing technologies of dusky kob, Argyrosomus japonicus, we studied the morphology and histology of the larval digestive system from hatching to 30 days after hatch. At hatch, the digestive tract appeared as a simple tube. The mouth was closed (endogenous feeding) and it opened by 65 degree days (DD). Supranuclear vacuoles appeared by 88 DD, initiating exogenous feeding. By 145 DD, the oil globule had disappeared. The stomach, intestine, rectum and gastric glands were visible by 224 DD. Number and size of supranuclear vacuoles began to decrease with progressive vacuolisation of the enterocytes and intestinal folds became obvious. The rectum was well differentiated at 338 DD but lacked supranuclear vacuoles in the enterocytes, suggesting limited nutrient absorption. At this stage, lipid absorption shifted to the hindgut, which now contained many lipid vacuoles. Goblet cells were visible in the midgut as gastric glands appeared, and their number increased from 292 DD. At the start of the third developmental phase, the larvae had a fully functional digestive system.     

Oral bovine serum albumin immune‐stimulating complexes improve the immune responses and resistance of large yellow croaker (Pseudosciaena crocea,Richardson, 1846) against Vibrio alginolyticus

This study aimed to investigate effects of bovine serum albumin immune‐stimulating complexes (BSA ISCOMs) on immune‐related genes expression, serum nonspecific immunity and disease resistance of large yellow croaker (Pseudosciaena crocea). Fish were fed diets containing 3.5 ml of BSA ISCOMs per kg feed (experimental group) or 3.5 ml of phosphate‐buffered saline per kg feed (control group) for 1 week. The liver, spleen, head‐kidney tissues were sampled for determining gene expression of myxovirus‐resistant protein (Mx), major histocompatibility complex class II alpha chain (MHC II α), tumour necrosis factor‐alpha (TNF‐α) and interleukin‐10 (IL‐10) 30 and 90 days after feeding. Also, blood samples were collected for determining activities of serum superoxide dismutase (SOD), interferon alpha (IFN‐α), TNF‐α and alkaline phosphatase (ALP). TNF‐α and MHCⅡα gene expression in the liver, spleen, head‐kidney, as well as IFN‐α, TNF‐α and ALP activities in the serum, of experimental fish were significantly higher 30 days after feeding; while only TNF‐α and MHC II gene expression in the head‐kidney remained upregulated 90 days after feeding. The cumulative mortality of the experimental fish was significantly lower than control. This study indicated that BSA ISCOMs improved the immune response and induced protective immunity in large yellow croaker.     

斑点叉尾对全植物蛋白饲料的胃排空及消化道内容物特性研究

为研究斑点叉尾(鱼回)[体质量(115.55±7.54)g]对全植物蛋白饲料的胃排空,实验比较了3种常用数学模型对其排空曲线的拟合程度,同时探究了摄食过程中消化道内容物的水分、pH和消化酶的变化规律.结果发现,3种数学模型均可较好地描述斑点叉尾(鱼回)胃排空曲线,平方根模型最适于定量描述,指数模型次之,线性模型较差.根据平方根模型分别计算得到斑点叉尾(鱼回)胃50％排空时间为12.8 h(以干重计),完全排空约36 h.在摄食后0～36 h内,内容物水分含量在后肠保持不变,在胃部呈缓慢上升趋势,而在前肠和中肠则呈先上升后下降趋势.消化道各段内容物pH在摄食后3h内均显著下降,3～30 h间总体保持平稳状态,在30 h后又呈显著上升趋势.消化道各段蛋白酶、脂肪酶和淀粉酶比活力在摄食3h内显著上升,并在3～30 h内保持相对稳定水平,摄食30 h后呈显著下降趋势.整个摄食过程中,消化道各段消化酶比活力大小依次为前肠＞中肠＞后肠＞胃.研究表明,斑点叉尾(鱼回)在摄食过程中,消化道各段内容物的水分、pH和消化酶比活力均随时间呈现相应的规律性变化.而这些内环境参数的相互作用,综合影响了特定胃排空时间的形成.     

Ontogenetic development of digestive enzymes and effect of starvation in miiuy croaker <Emphasis Type="Italic">Miichthys miiuy</Emphasis> larvae

The ontogenetic development of the digestive enzymes amylase, lipase, trypsin, and alkaline phosphatase and the effect of starvation in miiuy croaker Miichthys miiuy larvae were studied. The activities of these enzymes were detected prior to exogenous feeding, but their developmental patterns differed remarkably. Trypsin activity continuously increased from 2 days after hatching (dah), peaked on 20 dah, and decreased to 25 dah at weaning. Alkaline phosphatase activity oscillated at low levels within a small range after the first feeding on 3 dah. In contrast, amylase and lipase activities followed the general developmental pattern that has been characterized in fish larvae, with a succession of increases or decreases. Amylase, lipase, and trypsin activities generally started to increase or decrease at transitions from endogenous to exogenous feeding or diet changes, suggesting that these enzymatic activities can be modulated by feeding modes. The activities of all the enzymes remained stable from 25 dah onwards, coinciding with the formation of gastric glands and pyloric caecum. These results imply that specific activities of these enzymes underwent changes due to morphological and physiological modifications or diet shift during larval development but that they became stable after the development of the digestive organs and associated glands was fully completed and the organs/glands functioned. Trypsin and alkaline phosphatase were more sensitive to starvation than amylase and lipase because delayed feeding up to 2 days after mouth opening was able to adversely affect their activities. Enzyme activities did not significantly differ among feeding groups during endogenous feeding; however, all activities were remarkably reduced when delayed feeding was within 3 days after mouth opening. Initiation of larvae feeding should occur within 2 days after mouth opening so that good growth and survival can be obtained in the culture.