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131.
幼龄蓝孔雀日粮代谢率试验   总被引:4,自引:0,他引:4  
采用全粪收集法对雌雄混群饲养的20只幼龄(5月龄)蓝孔雀日粮(粗蛋白质水平28.20%,总能水平18104.4kJ/kg)中能量、粗蛋白质、干物质、粗脂肪、无氮浸出物和粗纤维的代谢率进行了测定,其结果分别是:81.72%、59.80%、75.46%、46.73%、88.55%和58.71%。  相似文献   
132.
Ten isonitrogenous (350 g kg1-crude protein) diets incorporating raw and soaked deoiled sal (Shorea robusta) seed meal at 200, 300,400, 500 and 600 g kg?1 into a fish-meal-based diet were fed to rohu, Labeo rohita (Ham.), fingerlings for 60 days and fish performance was studied. Tannin from raw salseed meal could be reduced from 34 to 7 g kg?1 by soaking in water for 16 h at room temperature. In terms of growth response, food conversion ratio and protein efficiency ratio, a diet containing 200 g kg?1 soaked salseed meal resulted in significantly (P < 0.01) the best performance of the fish. Apparent protein digestibility (APD) values decreased with increasing level of oilseed meal. Carcass protein was highest in fish fed diets containing 200 g kg?1 soaked salseed meal. The results showed that deoiled salseed meal can be incorporated in carp diets up to 200 g kg?1 and 300 g kg?1 in raw and treated forms respectively.  相似文献   
133.
Diet of larval and juvenile pikeperch (Stizostedion lucioperca) reared in ponds wasinvestigated and compared with the diet ofpikeperch from a reservoir. The standard lengthof first feeding pikeperch larvae in ponds was6.1 mm, on average, and although rotifers werepresent in the diet, their numericalcontribution can be considered asinsubstantial. Rotifers were soon replaced bynauplii of cyclopoid copepods, which werehighly positively selected and contributedlargely to the diet up to a larval length of 10 mm.Daphnia spp. were consumed from the onsetof exogenous feeding, but were not positivelyselected until 15 mm. Anothersmaller cladoceran Bosmina longirostriswas highly negatively selected and did notcontribute significantly to the diet. A clearpositive selection for larger relatively tosmaller prey and a preference for Daphniafrom a body length of 15 mm onwards could beobserved. In the reservoir, rotifers were notfound in the diet of pikeperch larvae even inthe smallest individuals. Dominant food itemswere nauplii and 1st copepodite instar ofEudiaptomus gracilis and Cyclopsspp. Cladocerans – Daphnia galeata andto a lesser extent Diaphanosomabrachyurum appeared in the pikeperch diet at alength of about 10 mm. A shift from copepods toDaphnia spp. and especiallyLeptodora kindtii could be recognised inpikeperch at a length of 20 mm. When comparing ourdata from nursing ponds with the data fromímov reservoir, similar trends in dietcomposition were observed.Growth of pikeperch was found significantlyfaster in nursing ponds than in the reservoir.Slow growth of reservoir pikeperch was probablyan artefact due to the prolonged spawningperiod in the reservoir. Larvae and juvenilesfrom later spawnings decreased the average sizeof the population over the studied period. Innursing ponds lowest average standard length atharvest was found in the pond with the highestnumbers of fish, and vice versa in the pondwith the lowest numbers the largest standardlength was recorded. This result corresponds tothe increased intracohort food competitionamong juvenile pikeperch with increasingstocking density.  相似文献   
134.
The influence of water temperature (17 and 25 °C) and a period of fasting on the self-selection of macronutrients were examined in common carp held on a 12:12-h light/dark cycle. Eight replicate groups of juvenile carp (ca. 15 g body weight at 17 °C and 25 g at 25 °C) were fed with three test diets [high-protein (HP), high-fat (HF) and high-carbohydrate (HC) diets] by individual self-feeders for 3 weeks, followed by a 2-week period of fasting and then 3 weeks of refeeding. At 17 °C, the carp initially selected the HP and HF diets [HP/HF/HC (%)=38:40:22], whereas at 25 °C, the carp selected the HP diet over the others (55:21:24). After fasting, the carp tended to increase their demand for the HF diet at 17 °C and for the HC diet at 25 °C, but the overall self-selection of the test diets did not differ markedly from that prior to fasting. Carp held at 17 °C had higher relative whole body fat content and plasma triglyceride concentration; the latter decreased markedly during fasting. These results suggest that water temperature influences the macronutrient selection by carp: a relatively high demand for both protein and fat at 17 °C and for protein at 25 °C. Two weeks of fasting, however, did not markedly alter their macronutrient selection.  相似文献   
135.
Mass seed production depends a great deal on the development of adequate artificial diets, which in turn depends on the development of methods to speedily and reliably assess the nutritional value of experimental diets. This study examined the sensitivity of light histological and ultrastructural criteria to detect differences in the nutritional value of diets for the Japanese spiny lobster, Panulirus japonicus (V. Siebold), phyllosoma larvae. The acceptability of diets, the apparent absorption of lipids and carbohydrates by the midgut gland cells, and the characteristics of various cell types were determined in 43-, 106- and 143-day-old intermoult phyllosoma fed diets of Mytilus edulis (L.) ovary alone (MO) or in combination with Anemia (MO+AR), which so far have given the best results in terms of growth and percentage of metamorphosis into puerulus, and two other diets considered less efficient, viz. Mytilus edulis testis (MT) and Artemia (AR). Acceptability of all diets attained 100% within 10 min of feeding as revealed by observation through the semitransparent cuticle of the larvae. Histological examination of larvae that ingested comparable amounts of food revealed pronounced variation in the absorption of lipids and carbohydrates by the midgut gland cells (AR相似文献   
136.
The effects of changes in the feeding regime on growth rate, body composition and fatty acid content of body lipids were monitored during the production cycle of European eels (Anguilla anguilla) in a fish farm, from elvers to commercial size (> 100 g).A high variation in growth rate obliged periodic grading. The fat content in the body of the eels notably increased over the study period in a direct relationship with size. At commercial size, a certain degree of sexual dimorphism was apparent, as were differences in dorsal coloration. At this stage, females were clearly larger than males and had a greater amount of body fat.Changes in dietary lipid composition (moist natural food, pellet foods with low and high fat content) influenced fatty-acid composition of body and muscle lipids. No differences between sexes were recorded in this respect. In general, indices of the nutritional quality of body lipids decreased progressively (in terms of the ratio between saturated, on the one hand, and mono- and polyunsaturated, on the other). However, the high fat content of the eels' edible fraction provides an equally high amount of the strongly recommended highly unsaturated fatty acids of the 3 series (HUFA3). © Rapid Science Ltd. 1998  相似文献   
137.
Refractory epilepsy is a common disorder both in humans and dogs and treatment protocols are difficult to optimise. In humans, different non-pharmacological treatment modalities currently available include surgery, the ketogenic diet and neurostimulation. Surgery leads to freedom from seizures in 50–75% of patients, but requires strict patient selection. The ketogenic diet is indicated in severe childhood epilepsies, but efficacy is limited and long-term compliance can be problematic. In the past decade, various types of neurostimulation have emerged as promising treatment modalities for humans with refractory epilepsy. Currently, none of these treatment options are used in routine daily clinical practice to treat dogs with the condition. Since many dogs with poorly controlled seizures do not survive, the search for alternative treatment options for canine refractory epilepsy should be prioritised. This review provides an overview of non-pharmacological treatment options for human refractory epilepsy. The current knowledge and limitations of these treatments in canine refractory epilepsy is also discussed.  相似文献   
138.
Canine hereditary copper-associated hepatitis is characterized by gradual hepatic copper accumulation eventually leading to liver cirrhosis. Therapy is aimed at creating a negative copper balance with metal chelators, of which d-penicillamine is the most commonly used. d-penicillamine often causes gastro-intestinal side effects and life-long continuous therapy may lead to a deficiency of copper and zinc. The aim of the current study was to investigate the effect of a low-copper, high-zinc diet as an alternative to continuous d-penicillamine treatment for the long-term management of canine copper-associated hepatitis.Sixteen affected Labrador retrievers were followed for a median time period of 19.1 months (range, 5.9–39 months) after being effectively treated with d-penicillamine. The dogs were maintained on a diet containing 1.3 ± 0.3 mg copper/1000 kcal and 64.3 ± 5.9 mg zinc/1000 kcal. Liver biopsies were taken every 6 months for histological evaluation and copper determination. Plasma alanine aminotransferase (ALT) and alkaline phosphatase, as well as serum albumin were determined.Dietary treatment alone was sufficient to maintain hepatic copper concentration below 800 mg/kg dry weight liver in 12 dogs during the study period. Four dogs needed re-treatment with d-penicillamine. ALT activity and albumin concentration were not associated with hepatic copper concentration, but showed a significant association with the stage and grade of hepatitis respectively. In conclusion, a low-copper, high-zinc diet can be a valuable alternative to continuous d-penicillamine administration for long-term management of dogs with copper-associated hepatitis. The copper re-accumulation rate of an individual dog should be considered in the design of a long-term management protocol and in determining re-biopsy intervals.  相似文献   
139.
140.
The purpose of this study was to determine how insulin and leptin concentrations varied in a large population of privately owned horses. Further, the study was designed to examine the relationships between insulin and leptin with innate (sex, age, breed) and managerial (diet, exercise) factors in these horses. Resting blood samples (for determination of glucose, insulin, and leptin concentrations), body condition scores, feed information, and health history were collected from 366 privately owned horses. In this group of horses, 48% were considered overweight (Body Condition Score ≥6) and 8% were considered hyperinsulinemic (insulin concentrations >30 μU/mL). Confirming the findings of studies within research herds, both insulin and leptin concentrations were found to be correlated with body condition score (P < .001). It was also found that geldings had higher insulin concentrations than mares (P < .05). Ponies were found to have higher insulin and leptin concentrations as well as higher body condition scores, than several other breeds examined. While not a specific measure of insulin sensitivity, resting insulin concentrations have been associated with quantitative measurements of insulin sensitivity and may be useful in large-scale studies for estimating insulin and glucose dynamics. Because of the association between insulin resistance and obesity with diseases such as laminitis, the findings of the present study may help owners identify horses that may be at risk for the development of such conditions.  相似文献   
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