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1.
Studies on vitamin B6 and pantothenic acid conducted with pigs, poultry and veal calves are presented to demonstrate the difficulties involved in research on B vitamins. The analysis of the B vitamins already poses problems, so that recommendations on dietary requirement must be seen in the light of the respective analytical procedures used. A distinction must be made between the minimum and optimum requirements of the animals. Today, the dietary provision of the optimum requirements is of priority and needs suitable and sensitive biochemical criteria or performance criteria for assessment.Studies using early-weaned and market pigs demonstrate that, in the case of vitamin B6, the urinary xanthurenic acid secretion after a tryptophan load and the activities of the serum transaminases are suitable biochemical criteria to diagnose suboptimum supply. Though these criteria were less responsive in poultry than in pigs, nevertheless, when the supply of vitamin B6 was suboptimal in broiler chicken, the body's retention of dry matter, nitrogen and energy, providing measures of true performance, proved to be affected adversely.The assessment of the optimum vitamin B requirement for practical feeding rations is illustrated with results from studies on the pantothenic acid requirement of broilers and market pigs. On the basis of live weight gain and feed efficiency, and also taking into consideration biochemical criteria provided by pantothenic acid and coenzyme A levels in the blood and liver, an optimum pantothenic acid requirement of 8 mg per kg of feed is recommended for broilers and 9 mg per kg of feed for market pigs. The dietary requirement of piglets, market pigs and broilers for vitamin B6 is estimated to be 3 mg per kg of feed.  相似文献   

2.
Two tests, using commercial White Leghorn layers and simplified rations, were conducted to determine the need for certain supplemental B‐vitamins. Varying levels of a multiple supplement (containing riboflavin, pantothenic acid, niacin and choline) were used in the first test. A factorial arrangement of treatments, using single and combination additions of riboflavin, pantothenic acid and niacin, was employed in the second test.

During the first test all supplemental vitamin levels resulted in a highly significant increase in egg production and egg size. The lowest dietary supplemental vitamin level was just as adequate as higher levels. Food consumption, body weight gain, viability and specific gravity of eggs were not significantly affected by B‐vitamin fortification.

Riboflavin supplementation resulted in a significant increase in egg production in the second test. The specific gravity of eggs was significantly decreased due to riboflavin supplementation. The addition of niacin and pantothenic acid to the basal ration did not significantly influence performance. Riboflavin was the only vitamin which exerted an appreciable influence on egg size during the second test.  相似文献   


3.
畜禽维生素需要量是指畜禽维持正常生命活动、生长发育和繁殖活动所需的维生素。但随着畜牧场的规模化和集约化发展,饲料供应商或畜禽生产者对畜禽维生素的供给可能不适应实际畜禽对维生素的需要量。本文综述了影响畜禽维生素需要量的因素,即畜禽体因素、药物与饲料中的成分和维生素的稳定性,为畜禽的维生素供给提供参考。  相似文献   

4.
1. The influence of different forms of dietary selenium (Se) on vitamin E (alpha-tocopherol) and Se contents of egg yolk and chicken meat was investigated. 2. Eggs were collected from laying hens subjected to 4 different dietary treatments after 24 weeks of age. Treatments compared the effects of inorganic Se supplementation (selenite) to those of organic (Se-enriched yeast, Se-enriched alga Chlorella) supplements. In a second experiment the effect of the above organic dietary Se supplementation on the alpha-tocopherol contents of meat from broiler chickens was evaluated. 3. Dietary Se supplementation increased the alpha-tocopherol content of egg yolks from 297 mg/kg dry matter in treatment without supplementation to 311 mg/kg when selenium was supplemented as selenite, and to 370-375 mg/kg when organic supplements were used. The Se and alpha-tocopherol contents of breast and thigh meat in broilers were significantly increased by organic dietary Se supplementation. 4. The inclusion of organic dietary Se sources in the diets of laying hens and broilers would enhance the nutritional value (vitamin E and Se contents) of products (eggs and meat) for human consumption.  相似文献   

5.
Chemical composition of meat-and-bone meals (n = 22), poultry by-product meals (n = 12), blood meals (n = 6), bone meals (n = 4) and feather meals (n = 8) indicated a slight degree of overdrying. Crude fat and ash contents were within the acceptable limits. Mineral elements of bones were determinative in the element pattern of meat-and-bone meals as indicated by the significant correlations between Ca, P and Mg. Crude protein was in negative regression and correlation with crude ash content (r = -0.81; P less than 0.001). This was more pronounced when the data were expressed in fatless dry matter (r = -0.94; P less than 0.001). Crude protein also showed significant negative correlations with Ca, P and Mg contents, offering the possibility to predict their levels from nitrogen content. Meat-and-bone meals and poultry by-product meals were relatively rich sources of riboflavin, niacin, pantothenic acid and biotin, whereas their pyridoxine and thiamine contents were low. Blood meals, bone meals and feather meals were found to be negligible vitamin B sources. Vitamin B and crude protein content of abattoir by-product meals showed uncertain correlations.  相似文献   

6.
Three experiments were carried out to investigate the involvement of vitamins in the fatty liver and kidney syndrome. The compounds studied, singly and in combination, were thiamin, riboflavin, nicotinic acid, pyridoxine, pantothenic acid, biotin, folic acid vitamin B12, ascorbic acid, choline and inositol and of these, only biotin prevented the syndrome. The minimum levels of supplemental dietary biotin required to prevent mortality varied from 0-05 to 0-15 mg/kg, depending on the diet. These levels were higher than the amounts required for maximum liveweight.  相似文献   

7.
Blood concentrations of thiamin, biotin, nicotinates, pantothenates, folates, riboflavin, vitamins A, B6, B12, C, E, beta-carotene and choline were analyzed in healthy animals (23 horses, 25 dogs, and 29 cats). B-Complex vitamins and choline also were analyzed in the liver of the dogs and cats. Vitamin concentrations in the blood and livers of dogs were similar; however, blood vitamin A and beta-carotene concentrations were lower in the cat than in the dog. Horses had a higher B12 blood concentration than did the dogs and cats. These data can be useful for detecting overt and hidden vitamin deficits in these species due to various conditions.  相似文献   

8.
维生素D是家禽需要的重要维生素之一。本文阐述了家禽维生素D的来源、新陈代谢和生物学功能、影响家禽维生素D需要量的因素以及维生素D的缺乏或过量对家禽生长发育和生产性能的影响 ,也为进一步研究维生素D提供了借鉴  相似文献   

9.
OBJECTIVE: To assess effects of high dietary amounts of vitamin C or vitamin E and oxidative stress on the heart and growth performance of broilers maintained at an altitude of 2,200 m above sea level. ANIMALS: 360 chicks (1-day-old broilers). PROCEDURE: Birds were randomly assigned to 3 groups (120 chicks/group). Each group of birds was fed a specific diet (control group, basal diet containing 12 mg of vitamin E (DL-alpha-tocopherol acetate)/kg of feed without additional ascorbic acid; vitamin E group, basal diet supplemented with 75 mg of vitamin E/kg of feed; and vitamin C group, basal diet supplemented with 400 mg of ascorbic acid/kg of feed) throughout the entire 7 weeks of the study. Feed consumption and body weight of chicks were recorded on a weekly basis. Nine randomly selected birds from each group were euthanatized each week. Remaining birds were euthanatized at the end of the study. Samples of cardiac tissues were obtained to measure thiobarbituric acid reactive substances (TBARS), an indicator of oxidative stress. RESULTS: Vitamin E-supplemented diets resulted in better growth performance, lower rates of feed conversion, and lower TBARS content. Vitamin C-supplemented diets resulted in lower feed consumption and lower rates of feed conversion. When used separately, neither of the vitamins had any effect on mortality attributable to ascites syndrome. CONCLUSION AND CLINICAL RELEVANCE: It is recommended that diets supplemented with vitamin C, vitamin E, or both be fed to broilers maintained at an altitude of 2,200 m above sea level to improve growth performance.  相似文献   

10.
Forty-eight growing pigs were randomly assigned to five dietary groups and penned individually. They received a diet based on barley, wheat, corn and soya bean meal according to requirement. The experimental groups were supplemented with 400% or 800% of vitamins B(2), B(6) and pantothenic acid, or 400% or 800% of biotin, while all other vitamins were administered according to requirement. Growth performance, carcass characteristics, aspartate aminotransferase (AST), and content of vitamins in blood, liver and muscles were recorded. Growth performance showed no influence of supplementation, while backfat thickness in the group with 800% B(2)/B(6)/pantothenic acid was significantly higher. Content of B(2) in blood, liver and muscle was similar in all groups. Content of B(6) in blood and liver showed significant differences according to supplementation. The content of vitamin B(6) in muscle in the experimental groups was significantly higher than that in the control group. The content of pantothenic acid in blood and muscle in the experimental groups was significantly higher, while in liver all groups were significantly influenced by the supplementation level. Biotin content in liver showed no influence, but the content in plasma was significantly higher in the experimental groups and the content in muscle was significantly higher according to supplementation. The activity of AST showed no significant influence of the dietary vitamin level, but it was obviously decreased in the groups supplemented with biotin. The findings indicate that the dietary supplementation of vitamin B(2), B(6), pantothenic acid and biotin could not improve performance, but the contents in blood, liver and muscle.  相似文献   

11.
对婴幼儿配方乳粉货架期内的维生素损失进行了检测分析,研究发现,脂溶性维生素——维生素A、维生素D、维生素E、维生素K1的损失率较高,超过了20%。另外,婴儿配方乳粉中的叶酸损失率明显高于较大婴儿配方乳粉和幼儿配方乳粉;维生素B1、维生素B2、维生素B6、烟酰胺、泛酸、维生素C、生物素在货架期内较为稳定;充氮罐装和充氮盒装产品的维生素损失率相近。  相似文献   

12.
The effect of the oral administration of high dosages of vitamins C and E on the innate immune system of the seabream was investigated. Gilthead seabream (Sparus aurata L.) were fed four different diets for 45 days: a commercial diet as control, a 3g/kg vitamin C-supplemented diet, a 1.2g/kg vitamin E-supplemented diet or a diet containing both vitamin supplements. After 15, 30 and 45 days, serum ascorbic acid and alpha-tocopherol levels, growth, complement titers and head-kidney leucocyte phagocytic and respiratory burst activities were evaluated. The results showed that serum vitamin levels reflected dietary input. Fish fed the vitamin C-supplemented diet showed an enhanced respiratory burst activity, while fish fed the vitamin E-supplemented diet exhibited increased complement and phagocytic activities. All of these positive effects were found in fish fed the joint diet, as well as a synergistically enhanced respiratory burst activity at day 30. The results demonstrate that in vivo vitamins C and E exert a synergistic effect enhancing the respiratory burst activity of seabream phagocytes.  相似文献   

13.
One hundred 6-week-old susceptible cockerels were inoculated with a pathogenic strain of infectious bursal disease virus (IBDV) and kept in the same pen as 100 each of 6-week-old pullets, local chickens and broilers. The cockerels developed depression and diarrhoea on day 3 post inoculation (PI) and most of the pullets and some of the local chickens and broilers showed similar signs on day 4 PI. Loss in weight was severe and similar in the pullets and local chickens, being significantly greater than that in the broilers from days 3–11 PI. The total mortality was 85%, 66.7%, 30% and 20% for the pullets, cockerels, local chickens and broilers, respectively. The lesions were more severe in the pullets and local chickens than in the broilers. IBDV antigen and antibody were detected, respectively, in all the bursal and serum samples from the infected chickens tested. The contact exposure method used in this study simulates better what happens in nature than inoculation with IBDV. The reduced mortality observed among the local chickens, compared with that (61.5%) seen in earlier studies using intraocular inoculation of IBDV, may have been due to behavioural differences that tend to result in their ingesting a relatively low dose of the virus.  相似文献   

14.
Ten sets of 5 littermate pigs from each of 2 genetic strains were utilized to determine the impact of the dietary concentration of 5 B vitamins (riboflavin, niacin, pantothenic acid, cobalamin, and folacin) on growth from 9 to 28 kg of BW in pigs with high or moderate capacity for lean growth. All pigs (penned individually) were reared via a segregated, early weaning scheme, so that the lean growth potential of each strain could be expressed. The basal diet provided the 5 test vitamins at concentrations of total and estimated bioavailability equivalent to a minimum of 100 and 70%, respectively, of their estimated requirements (NRC, 1998) for 5- to 10-kg pigs. At a BW of 9 +/- 0.9 kg, pigs within each litter were allotted to the basal diet supplemented with sources of the 5 test vitamins equivalent to an additional 0, 100, 200, 300, or 400% (bioavailable) of the NRC requirements. Pigs from the high lean strain consumed less feed (P < 0.05) and gained BW faster (P < 0.02) and more efficiently (P < 0.01) than pigs of the moderate lean strain. In both lean strains, the rate and efficiency of growth were improved (P < 0.01) as dietary B vitamin concentrations were increased. However, the dietary B vitamin concentrations needed to optimize G:F were greater (P < 0.03) in the high (>470% of NRC, 1998) vs. moderate (270%) lean strain. Based on these data, the dietary needs for 1 or more of the 5 B vitamins are greater than current NRC (1998) estimates, particularly in pigs expressing a high rate of lean tissue growth. The greater need for these vitamins is not associated with greater dietary energy intake or body energy accretion rate but is potentially due to shifts in the predominant metabolic pathways.  相似文献   

15.
B-vitamin supplementation of diets for feedlot calves   总被引:3,自引:0,他引:3  
B-vitamin supplementation of diets for 144 shipping-stressed crossbred calves (116 kg) at levels up to 10 times that recommended for growing pigs did not influence (P greater than .20) weight gain or feed conversion during a 56-d receiving trial. However, vitamin supplementation tended (P less than .10) to reduce morbidity. In a second trial, supplemental B-vitamins had no effect (P greater than .20) on efficiency of microbial growth or site and extent of digestion of organic matter, acid detergent fiber and N. Supplemental dietary riboflavin, niacin, folic acid, B12 and ascorbic acid were largely metabolized [degraded and (or) absorbed] anterior to the small intestine, with escape values of 1, 3, 10 and 0% of added vitamins, respectively, while dietary B6 and biotin largely escaped the rumen. Thiamine and pantothenic acid were intermediate in ruminal escape (52 and 22%, respectively). Small intestinal absorption of thiamine, niacin, riboflavin, B6 and B12 averaged 75, 79, 25, 79 and 48%, respectively. Coefficients for ruminal escape and microbial synthesis for each B-vitamin were calculated using the slope-ratio technique. Measured flows for thiamine, riboflavin and B12 in a third experiment were similar to flows predicted from escape and synthesis equations, though flow of niacin and B6 were under-predicted by 37 and 44%, respectively. Results are interpreted to indicate that intestinal B-vitamin supply can be predicted based on dietary composition and intake.  相似文献   

16.
Two experiments evaluated the relationship of vitamin E (source and level) and vitamin A (level) on the apparent absorption and retention of both vitamins in weaned pigs. Both experiments used a combined total of 460 crossbred pigs ([Yorkshire x Landrace] x Duroc), housed in elevated 1.2- x 1.2-m crates containing five pigs per pen. Experiment 1 was a 2 x 2 x 2 factorial arrangement of treatments in a randomized complete block design conducted in seven replicates. Levels of vitamin A (2,200 or 13,200 IU/kg), vitamin E (15 or 90 IU/kg), and two vitamin E sources (D-alpha-tocopheryl acetate [D-TAc] or DL-alpha-tocopheryl acetate [DL-TAc]) were evaluated over a 35-d period. Vitamin A or E levels and the two vitamin E sources did not affect pig performances to 20 kg BW. Serum retinol and alpha-tocopherol concentrations increased (P < 0.01) as the dietary level of each vitamin increased. Serum alpha-tocopherol declined as dietary vitamin E level increased when vitamin A level increased resulting in an interaction (P < 0.05). Serum alpha-tocopherol concentrations were higher (P < 0.05) at 35-d postweaning when D-TAc was the vitamin E source. Experiment 2 was a 3 x 2 factorial arrangement of treatments conducted in six replicates. Three levels of vitamin A (2,200, 13,200, or 26,400 IU/ kg) and two sources of vitamin E (D-TAc or DL-TAc) each provided at 40 IU/kg diet were evaluated over a 35-d period. Pig performances to 35-d postweaning were not affected by the dietary variables. Serum alpha-tocopherol (P < 0.01) and retinol (P < 0.05) concentrations increased as their respective vitamin level increased. Serum (P < 0.05) and liver (P < 0.01) alpha-tocopherol concentrations both declined as dietary vitamin A levels increased resulting in interaction responses. Serum alpha-tocopherol concentration was higher (P < 0.05) at 35-d postweaning when d-TAc was the vitamin E source. Dietary vitamin E sources had no effect on serum or liver retinol concentrations. These results demonstrated that both supplemental vitamin A and vitamin E increased in the blood as their dietary levels increased. However, as dietary vitamin A level increased, serum and liver alpha-tocopherol concentrations declined, suggesting a reduced absorption and retention of alpha-tocopherol when weaned pigs were fed high dietary vitamin A levels.  相似文献   

17.
18.
对内蒙古呼和浩特地区牛乳中多种维生素含量进行测定与分析。主要测定了牛乳中VA、VB2、泛酸、VC以及VE 5种维生素的含量,其中,VA、VB2、泛酸以及VE的检出率均为100%,VC检出率为87.5%,同时研究了不同季节对牛乳中维生素含量的影响。结果表明,VB2和泛酸含量较稳定,受季节影响小;VA和VE含量均不同程度受到季节的影响;VC含量波动较大,受自身性质和季节变化双重影响。通过研究呼和浩特地区牛乳中多种维生素含量,对乳制品企业强化维生素指标具有重要的指导意义,也为今后的研究者提供了更准确的数据资料。  相似文献   

19.
Ten poultry farms (broiler breeder pullets, layer pullets, and broilers) in the provinces of Entre Rios and Buenos Aires in Argentina were examined for presence of Eimeria spp. Litter samples obtained from flocks 7-11 wk old were taken to the laboratory for oocyst counting and sporulation, then concentrated for inoculation into coccidia-free chickens. Species were identified by prepatent period, oocyst size, location and appearance of lesions in the intestine, microscopic examination of mucosal smears, and histology (to confirm Eimeria brunetti). On this basis, Eimeria praecox was found in two samples, Eimeria mitis in two, Eimeria acervulina in nine, Eimeria maxima in seven, Eimeria necatrix in three, Eimeria tenella in seven, and E. brunetti in four. These results confirm the presence of all seven recognized species of Eimeria in chickens in the Republic of Argentina.  相似文献   

20.
1. A study was conducted to investigate the effects of several vitamins and trace elements chickens and in chickens experimentally infected with malabsorption syndrome (MAS). 2. Vitamins and trace minerals in feed were varied. Breeders received either a basal amount of vitamins and trace minerals (low mix) or an increased amount (high mix). Their progeny also received either a low mix or a high mix. Effects of different breeder and broiler mix combinations on broiler performance, heamatology, spleen weight and humoral response were examined in control chickens. The effects of the different feeds and breeder, broiler combinations at the severity and recovery of MAS infection were also studied. 3. In general, the immune system can be stimulated by addition of vitamins and trace minerals, without affecting the growth potential of the controls. The number of leukocytes increased on d 1 in the broilers descended from breeders receiving high mix. The response to Newcastle disease virus boost was affected by the different amount of vitamins. 4. When breeders received a high mix the number of infiltrating polymorphonuclear leukocytes in the intestine was higher compared with breeders receiving basal amounts of minerals and vitamins. Also the recovery rate of intestinal lesions, cystic crypts of Lieberkühn and villus atrophy, as observed by histopathology, was faster in the groups where the breeders received high mix.  相似文献   

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