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The objective of the study was to assess the effects of substitution milk and egg for soya products in breeding diets for rats, with concomitant decrease of the dietary protein level and supplementation with amino acids. Soya-containing (S) and two soya-free (NS and NSA) diets were evaluated as protein and energy sources, and their effects on reproductive performance during two cycles, and on the quality of the offspring were assessed. Organ weights were registered in females and blood parameters were determined in males. In the offspring males from S and NS groups, plasma LH, testosterone and prolactin levels were measured on the 22nd and the 60th day of life. The S diet contained more protein of smaller concentration of methionine and cystine and lower biological value than both NS and NSA diets and promoted similar post-weaning growth rate, similar body weight changes of dams during gestation and lactation and slightly lower mating efficiency. Within each reproductive cycle, the number and individual and total body weight of newborn and weanling pups did not differ but in two cycles mean number of neonates per litter and mean litter weight were significantly lower on S than on NSA diet. Plasma concentration of hormones did not differ in 22-day-old offspring males while in the older ones LH and prolactin levels were higher in animals fed on S than on NS diet. It is concluded that replacing soya protein by milk and egg protein with concomitant lowering dietary protein level and amino acid supplementation does not impair the growth rate and tends to improve reproductive performance. Feeding soya-free vs. soya-containing diets differentiates hormonal status of young males.  相似文献   
2.
An experiment was carried out on multiparous sows to study the possibility of total substitution of soybean oil meal by whole horsebean in the lactation diet. Two groups of five sows were kept in metabolism crates during a 5-week long lactation, and their total excreta were collected for 5 days each week. The animals received a diet mainly composed of barley, in which the protein concentrate was soybean oil meal (“soybean” group), or whole horsebean (“horsebean” group) supplemented with d-l methionine (Table I). The two diets were isonitrogenous (14% protein). Milk production and gros composition were estimated at different stages of lactation. The amino acid content of the milk and the plasma level of free amino acids were determined around day 21 of lactation.The performance of the two groups of sows were similar (Table II): the litters were equalized at farrowing, the number of piglets weaned (8.8) and their mean weight at different stages of lactation were identical. Milk production, composition (Table III) and amino acid content (Table IV), and the output of milk constituents were similar. There was some tendancy for the apparent protein digestibility of the “soybean” diet to be higher (81.5% vs 79.6%), partly due to the greater digestibility of dry matter (82.3% vs 81.8%) caused by the lower crude fibre content of this meal. The nitrogen retention coefficient and nitrogen production in the milk were the same in the two groups of sows (Table V). The amino acid availability, estimated with the plasma level of free amino acids, did not show important differences between the diets. The similarity of the results allows the conclusion that whole horsebean supplemented with d-l methionine can be used as the sole protein concentrate in the diets of lactating sows. Moreover, the null nitrogen balances obtained during lactation with a daily intake of 700 g protein may lead to a possible lowering of the protein recommendations, while insisting on the energy supply during the same period.  相似文献   
3.
In a two-factorial experiment on 96 young male rats, the effects of substituting 10% raw potato starch (PS), pectins (PEC), or cellulose (CEL) for corn starch (CS) were studied using an unsupplemented protein-free (PF) diet or a PF diet supplemented either with DL-methionine or urea. The pH and the short chain fatty acids (SCFA) content in caecal digesta, as well as caecal digesta and tissue weights were determined and used as the criteria of caecal fermentation intensity. Blood urea level, amount of N excreted via faeces and urine, DAPA content, and amino acid composition of faecal protein were analyzed as indices of protein metabolism. A 10-day adaptation period to the carbohydrates fed with the casein diet preceded the experimental period of feeding the respective carbohydrates with protein-free diets. Dietary carbohydrates significantly influenced total and individual SCFA content in caecal digesta, as well as other parameters related to the intensity of fermentation. Potato starch and pectins were more intensively fermented than cellulose. Supplementation of the PF diet with methionine and urea affected only caecal isobutyric and valeric acid content in a way dependent on the carbohydrates present in the diet. Carbohydrates significantly altered the routes of N excretion. Faecal excretion was increased by all carbohydrates studied compared to corn starch, pectins had the most marked effect. Urinary excretion was significantly increased by cellulose (as compared with the PEC and PS groups) and decreased by pectins as compared with all other groups. There was an interaction between the effects of carbohydrates and type of protein-free diet on faecal and urinary excretion. The sum of amino acids in faecal protein was the lowest on the PEC diet, but the amino acid composition expressed as a per cent of total amino acid content was similar in all groups. It can be concluded that dietary carbohydrates alter the excretion patterns of endogenous nitrogen in rats in different ways and that this effect is related to the intensity of their fermentation in the hind gut.  相似文献   
4.
Two diets containing either soybean meal (SBM) or SBM and potato protein concentrate (PPC) in proportion of protein 1:1 (diet BS and BPP, respectively), were fed each to 22 females and 22 males from the age of 4-5 weeks throughout two reproductive cycles. A commercial closed-formula SNF diet containing unknown amount of potato protein was fed till the end of the first reproductive cycle. All three diets were also fed during 21 days following weaning, each to 10 offspring males born in the first cycle. The solanidine glycoalkaloids (GA) content in PPC was 2316 mg/kg DM. Feeding diets containing potato protein did not affect pregnancy rate, number and conformation of neonates and number of pups weaned (in all litters number of neonates left with dams being reduced to eight) but it depressed their body weight (weight of weaners on BPP diet only in the first cycle). Growth rate of the offspring males did not differ but feed intake was lower and feed conversion was higher on BPP than on BS and SNF diets. Feeding of BPP diet to offspring did not affect mass of body organs but increased blood urea and albumin concentrations while feeding SNF diet increased relative weight of small intestine and liver and raised blood concentrations of alanine amino transferase, albumin, protein, urea and cholesterol. In dams sacrificed after two cycles only relative weight of uterus and ovaries were lower in females fed on BPP than on BS diet. It is concluded that feeding moderate amounts (6.4%) of high-GA PPC does not impair reproductive performance, does not induce malformation of pups but depresses foetal and postnatal growth rate till weaning but not after weaning.  相似文献   
5.
In 2 two-factorial experiments, each conducted on 80 growing male rats, the effects of substituting 10% raw potato starch (PS), pectins (PEC), or cellulose (CEL) for wheat starch (WS) and the addition of tannic acid to WS (WSTA) were studied using diets differing in protein quality. Casein unsupplemented or supplemented with DL-methionine and gluten unsupplemented or supplemented with lysine, methionine and tryptophan were used as protein sources in Experiment 1 and 2, respectively. Parameters indicative of caecal fermentation intensity (pH, acetic, propionic and butyric acid contents, digesta and tissue weight) and of protein metabolism (urea blood concentration, faecal and urinary nitrogen excretion) were determined. Ten-day balance experiments were preceded by a 10-day adaption period to respective carbohydrates given in a diet containing balanced protein. In both experiments the type of carbohydrates affected the caecal concentration of individual and total SCFA and other parameters of fermentation intensity. Pectins and potato starch were fermented more intensively than cellulose. Faecal N excretion was increased by all carbohydrates substituted for cereal starch, and by tannic acid. Urinary excretion was greater on CEL than on PEC and WSTA containing casein and on other diets containing gluten. In both experiments urinary N excretion was the lowest on PEC diets. Protein quality had the greatest effect on apparent biological value and net protein utilization but all indices of protein utilization were also affected by carbohydrates. It is concluded that not only the amount of N excreted in faeces but also in urine is affected by the type and fermentability of carbohydrates.  相似文献   
6.
Two groups of 26 male and 26 female rats at the initial age 30 +/- 2 days were fed during 31 weeks on diets containing 20 percent of yellow lupin seeds having low (LG) or high (HG) gramine content. The animals were mated twice within nutritional groups, 1 male: 1 female, and their main reproductive parameters were recorded. In both reproductive cycles body weight of females at mating, after parturition and after 21-days lactation was lower in HG than in LG group. Fertility rate and body weight of neonates were not affected by the diet while number of neonates per litter tended to be lower by 0.7 and 0.8 pups in HG than in LG group. Body weight of weaners was also substantially smaller in dams fed on HG than LG diet. Relative weight of spleen but not of liver, kidney and heart was significantly greater in HG females. Four weeks old males and females issued from the first litters born to LG and HG animals (ten males and ten females per treatment) were fed individually on respective diets during 3 weeks. Feed intake and growth rate did not differ between the treatments. In males relative weight of liver and testicles was greater, while hematocrit and red blood count were lower in HG than in LG group. In females organ weights did not differ. Activity of liver enzymes determined in males was not affected by the diet. It may be concluded that high-gramine lupin affects negatively lactational performance, probably via lower feed intake, but it does not induce apparent teratogenic effects in the progeny.  相似文献   
7.
The effects of feeding autoclaved commercial SSNIFF (SN) diet and diets containing soya bean (S) and casein (C) to growing conventional (CON) and specified pathogen‐free (SPF) rats were determined. Diets S, C and SN, autoclaved at 121 °C during 20 min (T1), at 134 °C during 10 min (T2) and non‐autoclaved (T0), were fed during four weeks, each to 8 CON males and 8 females of mean initial body weight 56 g, kept individually. Diets S, C and SN, autoclaved at T1, were fed during two months, each to 20 SPF males and 20 females of mean initial body weight 58 g, kept in group of 5 animals per cage. In CON rats, autoclaving did not affect feed intake and weight gain, decreased thyroid and stomach weight, increased caecal tissue and digesta weight, and concentrations of isobutyric, isovaleric and valeric acid in caecal digesta. Among biochemical blood parameters, autoclaving decreased only total protein concentration and aspartate aminotransferase activity. Feeding C diet resulted in lower feed intake and weight gain in CON and SPF males. Diet affected organ weights and the greatest differences were found in rats on SN diet for weights of stomach, caecum and female reproductive organs. Diet affected concentration of all short‐chain fatty acids, pH and weight of caecal digesta, the most important being the greatest butyric acid concentration on SN diet and isoacids on C diet. It is concluded that autoclaving of both soya‐containing and soya‐free diets does not affect negatively animal performance and physiology.  相似文献   
8.
The effects of feeding varied levels of low- and high-gramine yellow lupin seeds (LG and HG, respectively), and of synthetic gramine added to the diets in amounts ranging from 0.15 to 1.2 g per kg were investigated in one experiment on growing chicken and in two experiments on growing rats. The comparison of LG and HG lupin and the effect of 0.5 g gramine per kg of LG diet were determined in a growth-balance experiment with pigs. Organ weights and histology, blood parameters and activity of liver enzymes were determined. The response to HG lupin and gramine concentration varied among the species, the rats being more affected than chicken; no adverse effects of HG lupin or gramine were found in growing pigs. The common reaction of rats and chicken to the high levels of gramine (native or synthetic) was the decrease of feed intake and body gain. The increase of the relative weight of liver or kidney, changes in hematological parameters and liver enzymes were found only in rats. The estimated NOAEL (no-observed-adverse-effect level) of gramine was about 0.3 g/kg diet for rats, 0.65 g for chicken and at least 0.5 g for growing pigs.  相似文献   
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