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1.
In 9 experiments the vitamin A content of the livers of 64 newborn (still births and deaths up to 48 h p.p.) and 69 weaned piglets, 122 growers and 110 fattening pigs was investigated after slaughtering or autopsy. Liver samples were taken from 78 growers by means of biopsy after latarotomy. A fluorometric analysis of the plasma vitamin A level was made. At the time of birth the vitamin A content of the piglet livers was less than 100 IU/g and did not show any differences between the experiments. At the time of weaning, however, the livers of piglets from large-scale production showed a three times higher content (175 IU/g liver) in comparison to those from traditional production. Highly significant linear relations were established between the vitamin A content of the feed and the liver. According to these, a liver content of vitamin A of approximately equal to 30 IU/g is ensured by approximately equal to 2,000 IU in weaning piglets and by approximately equal to 800 IU vitamin A/kg feed in fattening pigs. The vitamin A activity of the beta-carotene in weaners was ascertained as less than 100 IU/mg. The plasma vitamin A level indicated the vitamin A status only in the range of deficient supply. A different plasma content could not be detected between 1,000 and 4,000 IU vitamin A/kg feed. According to this, a semilogarithmic relation was calculated according to the model of a saturation curve between the vitamin A content of the plasma and the liver. The threshold value for the decrease of the plasma level under 45 IU vitamin A/dl is 35 IU/g liver. Due to the low definiteness measure (B = 0.52) the relation cannot be applied to the individual animal. A contamination of 1,000 mg nitrite/kg feed had a low, and in the course of the experiment decreasing, influence on the vitamin A content of plasma and liver.  相似文献   

2.
In two experiments with 420 male cairina (Cairina moschata domestica L.) semisynthetic rations were used with vitamin A supplements between 0 and 10,000IU per kg feed. Clinical deficiency symptoms, such as coordination disturbances or horny growths at the oesophagus glands, could be prevented in the starter period up to 3rd week with 500IU vitamin A and in the fattening period between the 4th and 10th/11th weeks with a 250IU vitamin A supplement per kg feed. Cairina achieved an optimal fattening performance under the conditions tested with 1,000 IU in the starter period and with 500 IU vitamin A supplement in the fattening period. Under consideration of the vitamin A storage in the liver and a safety supplement of 4000 IU vitamin A per kg start feed (0-3 weeks) and 2,000 IU vitamin A per kg fattening feed (4-11 weeks) is suggested as requirement norm and mixed feed supplement.  相似文献   

3.
Live weight development and feed expenditure on 3 levels of crude protein supply and with isocaloric rations were investigated in scientific feeding experiments with 7 castrated male pigs each of the Bulgarian land race in the live weight range between 30 and 100 kg with a subdivision at 60 kg. The crude protein concentrations in the rations for the 3 groups were 17%, 15% and 13% in the first fattening period and 15% 13% and 11% in the second fattening period. In the two fattening periods the digestibility of the feed mixtures used was ascertained in experiments. The daily live weight gain in the three groups over the whole fattening period reached a high level of performance (836 g, 778 g and 757 g). The feed expenditure values were 3.3, 3.7 and 3.7 kg mixed feed (88% dry matter) per kg live weight gain. The highest protein supply resulted in the best weight gain performance and the lowest feed expenditure.  相似文献   

4.
Live weight development and feed expenditure were investigated on 3 levels of protein supply and isocaloric rations in scientific feeding experiments with 10 castrated male pigs each of the genetic origin land race pig X large white fed individually in the live weight range between 30 and 100 kg with a subdivision at 60 kg. In the air-dried matter the crude protein content of the feed mixtures used in the first fattening period was 17.6; 15.7 and 13.7% resp. and in the second fattening period from 60 kg live weight onwards 14.9; 12.8 and 11.4% resp. for the 3 test groups. In both fattening periods the digestibility of the rations and the N-balance were determined at 3 representative animals from each of the 3 groups. The following average live weight gains were achieved in the 3 test groups: 1st fattening period: 662; 592 and 539 g resp.; 2nd X fattening period: 709; 676 and 644 g resp. Feed expenditure over the complete fattening period was 4.2; 4.5 and 5.2 kg air-dried matter per kg live weight gain. The highest protein supply resulted in the best live weight gain performance and the lowest expenditure.  相似文献   

5.
Diseases and losses were registered in dependence on vitamin A supply with 2,035 pigs (6.5-114 kg live weight). The histologic examinations comprised various organs of 72 animals. The content of the main protein fractions as well as antibody titre after supplementing antigenes were determined in the serum of 104 animals. The feeding of a vitamin-A- and carotinefree casein-starch-respectively a Vitamin-A-free cereal-soybeanmeal-diet led to deficiency symptoms after 7-8 respectively 16-19 weeks of experiment particularly in the shape of nervous disturbances and voice affectations. Histologically a hyperplasia and a metaplasia of the epithelium of the big ducts in the salivory gland could be proved. The repletion of a part of the avitaminotic animals by means of oral (500 I.U./kg feed) and parenteral (500,000 to 1,000,000 I.U. i.m.) vitamin A administration is proof of a lack of vitamin A. Vitamin A and provitamin dosage did not influence diseases and losses with the exception of the occurrence of deficiency symptoms. The protein content of the serum as well as that of the globulin fractions alpha, beta, gamma did not change, the albumin content was lower in the groups without vitamin A (p greater than 0.05). Antibody titre against the lipopolysaccharide of salmonella dublin and human gamma globulin were diminished in piglets and fattening pigs fed vitamin A free (p less than 0.05). Taking the criterion of animal health, a vitamin A requirement higher than for growth (250 I.U./kg feed) cannot be derived.  相似文献   

6.
In seven experiments with 46,310 young animals from hatching to the 21st week the vitamin A supplement varied between 0 and 10,000 IU per kg mixed feed. Feed intake was significantly diminished in three out of seven experiments when chicken feed was given without vitamin A supplement. In the young chicken period 1,500 IU vitamin A supplement were sufficient for optimal body weight development, in the young hen period native carotene was sufficient. The variation of the body weight of the individual animals on the 126th day did not show any connection with vitamin A supply. The carotene content of the rations was sufficient to prevent deficiency symptoms. The livers and yolk sacs of one-day-old chickens on average contained 114 and 56 IU vitamin A/g substance when the parents had received mixed feed with 15,000 IU vitamin A/kg. There is a positive relation between the vitamin A supply of the young chickens and hens and the vitamin A content of the liver.  相似文献   

7.
Scientific feeding experiments were carried out with 5 castrated male pigs and 4 female animals of the genetic origin "Camborough" in the live weight range between 30 and 100 kg with a subdivision at 60 kg. In each test group the animals were fed individually and received rations with approximately equal contents of protein, amino acids, minerals and vitamins but different energy contents. Energy intake was adjusted to 3 levels of 100%, 85% and 70% of semi-ad-libitum intake. Apart from that, the digestibility of the feed mixtures used in the 2 fattening periods was determined. Having reached a live weight of 100 kg, 7 representative animals per group were slaughtered and a number of slaughtering parameters were registered. In all three test groups the daily live weight gain over the complete fattening period was very high (846, 819 and 778 g). Though the weight gain in group 3 with 70% of the energy supply of group 1 is significantly lower than in the other two groups, it is, however, only 70 g lower than in group 1. Consequently, the feed expenditure (2.6 kg mixed feed per kg live weight gain) in group 3 is by 20% lower than in group 1, in which the feed expenditure is 3.2 kg mixed feed per kg live weight gain. There were no significant differences on the weight gain performances and the registered carcass parameters between sows and castrated male pigs. Observed deviating tendencies are discussed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

8.
In three fattening experiments with 1344 male cairinas (Cairina moschata domestica L.) from hatching to the 77th day vitamin A supplement was reduced to 2500 IU/kg feed from hatching to the 21st day and to 1250 IU/kg feed from the 22nd to the 77th day. There was no supplementation of the feed with vitamin E or nicotinic acid. The reduction and elimination of the vitamin supplements on average did not have significant effects on fattening performance, feed intake, body weight, feed conversion and losses of animals in the starter and fattening periods. In the fattening period there was a tendency towards a higher intake and expenditure of feed in two experiments. Presumably the supplementation of 1250 IU/kg mixed feed is not always sufficient for an optimal fattening performance. In three production experiments with 33,850 cairinas no disadvantageous influence on fattening performance could be ascertained after a supplementation of 4,000 IU in the starter feed and 2,000 IU vitamin A in the fattening feed.  相似文献   

9.
105 growing sows in the live weight range were fed with 7 test rations with graduated energy and amino acid levels. The growth intensity was very much influenced by the daily energy consumption. On the basis of regression analysis the following linear relation between daily weight increase (y in g per kg live weight0,75) and the daily energy consumption (x in energetic feed units for pigs per kg live weight0,75) was calculated: y = -13,79 + 0,7037 x (r = 0,84, sb -0,0295). The interpolation with regard to live weight balance resulted in a maintenance requirement of 19,8 energetic feed units for pigs resp. 70 kcal net energy fat for pigs per kg live weight0,75. The methods of assessment chosen showed an increase of the energy requirement per 100 g additional live weight increase per day of a constant amount, independent of the live weight, of 142 energetic feed units for pigs resp. 497 kcal net energy fat for pigs.  相似文献   

10.
Studies of the energy metabolism at maintenance and growth levels after the feeding of rations with a crude protein content of 17-24% and 44-47% resp. were carried out with hybrid pigs of line 150 in the live weight range between 10 and approximately 50 kg. This paper gives information on the methods and the outlay of the experiment and presents results concerning feed intake, live weight development and digestibility. Feed intake increased on average with growing live weight by 30-35 g DM/kg live weight. Feed conversion ranged from 1.2 to 1.8 kg DM/kg live weight gain in the first period and from 2.3 to 3.2 kg DM/kg live weight gain in the last period. The digestibility of the energy in the rations with a crude protein content of between 17 and 24% averaged 80% and that of the rations with a crude protein content of 44-47% averaged 86%. In the course of ontogenetic development the digestibility increased up to about 30 kg LW. The influence of the nutritional level on the level of digestibility was unequal in the experiments. In one experiment a decrease (1% unit) and in two experiments an increase (1-3% units) of the digestibility after the feeding of growth level in contrast to maintenance level could be observed. The change of rations with a varying protein content did not result in an influence on the digestibility level in comparison with the constant feeding of one ration.  相似文献   

11.
Scientific feeding experiments were carried out with 7 male castrated pigs of the genetic origin land race pig X large white with the test animals fed individually and the rations containing approximately the same amounts of protein, amino acids, minerals and vitamins but varied amounts of energy. Energy intake was adjusted to three levels: 100%, 85% and 70% of semi-ad-libitum intake (group 1 = 100%). With regard to protein supply there was a subdivision into 30-60 and 60-100 kg live weight. In addition to this, the digestibility of the feed mixture used and the N-balance were determined in both fattening periods. Having reached 100 kg live weight, the animals were slaughtered and a number of slaughtering parameters was determined. The average daily live weight gain in the three test groups was 749, 664 and 540 g over the whole fattening period. The feed expenditure was 3.7, 3.9 and 4.3 kg mixed feed per kg live weight gain so that, with regard to live weight performance and feed expenditure the group with the highest energy supply showed the best results. The level of energy supply had a remarkable influence on the composition of weight gain; thus the amount of fat in the carcass of the animals of groups 3 was by 1.8 kg and 2.5 kg resp. lower than of the animals in groups 2 and 1.  相似文献   

12.
In a individual feeding experiment (348 days) 24 fattening bulls were given either a ration high in roughage (2.8 kg concentrate mixture, wheat straw ad libitum: group I) or high in concentrate (5.6 kg concentrate mixture, wheat straw ad libitum group II) supplemented with various levels of vitamin D3 (0, 250, 500, 1,000, 2,000, 4,000 and 8,000 IU per 100 kg body weight (bw) and day) and minerals as required. After 58, 101, 134, 172, 205, 277 and 340 days 25-OH-D3 plasma concentration was estimated. Fattening and slaughtering parameters were measured. The 25OH-D3 plasma concentration was significantly influenced by vitamin D3 supply, kind of ration and day of taking samples. 25-OH-D3 plasma concentration decreased below 5 ng per ml when vitamin D3 supply was less than or equal to 250 IU per 100 kg bw and day. The initial plasma levels were maintained when 500 IU vitamin D3 per 100 kg bw and day was given (6.6 ng per ml). Administration of greater than or equal to 1,000 IU per 100 kg bw and day increased 25OH-D3 plasma level (greater than 10 ng/ml). Plasma 25OH-D3 concentration was significant higher when bulls consumed diets rich in concentrate (10.6 and 18.2 ng/ml for I and II after 340th day). Differences in content of cell walls and crude fat of rations may be responsible for results. Daily weight gain of bulls amounted to 712 and 945 g when fed diets I or II. Dry matter intake and live weight gain were not significantly influenced by different vitamin D3 supply. Clinical symptoms of rachitis did not appear.  相似文献   

13.
The energetic utilization of rations with raw and steamed sugar beets, dried sugar beet pulp (16 measured values each), sucrose and apple pectin (8 measured values each) as supplement feed to a basic ration was measured at 4 growing pigs each in the live weight range of between 40 and 130 kg. The utilization of the energy in the rations amounted to 69.1 +/- 5.5, 68.3 +/- 7.1, 60.9 +/- 5.8, 70.5 +/- 4.1 and 69.9 +/- 6.9% (same sequence as above). The utilization values for the supplemented feedstuffs were 69.2 +/- 7.4, 68.0 +/- 10.0, 55.9 +/- 9.7, 72.2 +/- 7.6 and 71.7 +/- 17.3%. The average retention value of the digestible pectin was derived from the test results with dried sugar beet pulp and apple pectin as 5.8 kJ/g. An influence of the ontogenetic development on energy utilization cannot be derived from the comparison of the retention effect of digestible nutrients measured at growing pigs and that derived from adult pigs.  相似文献   

14.
Three long time individual feeding experiments (greater than 258 days) with 48 beef cattle each (dairy breed and beef breed, 50% each) were carried out in order to measure the influence of various vitamin A supply (0, 2,500, 5,000 and 10,000 IU vitamin A per 100 kg body weight and day) on fattening and slaughtering performance, vitamin A concentration of liver and serum as well as carotene concentration of serum. The bulls consumed corn silage (experiments 1 and 2; 9.4 and 18.3 mg carotene per kg dry matter) or NaOH-treated and pelleted straw (experiment 3; no carotene). The roughages were supplemented with 2 (exp. 1 and 2) and 3 kg (exp. 3) concentrate per day. The vitamin A supply of corn silage diet did not significantly influence the dry matter intake (exp. 1: means: 6.95; 6.91 to 7.05; exp. 2: means: 6.54; 6.53 to 6.54 kg dry matter per animal and day) and the daily weight gain of bulls (exp. 1: means: 1076; 1028 to 1157; exp. 2: means: 1058; 1041 to 1057 g per animal). The bulls consumed 8.87 kg dry matter per day, the daily weight gain amounted to 1030 g per animal and day in experiment 3. The bulls of unsupplemented group reduced feed intake and weight gain after 150 days, an additional vitamin A supply was necessary. At the end of experiments 1 and 2 the liver vitamin A concentration of unsupplemented groups amounted to 38.8 and 65.9 mumol/kg, it increased after vitamin A supply (up to 153.4 mumol/kg). Feeding of pelleted straw effected a liver vitamin A concentration lower than 10 mumol/kg except the group supplemented with 10,000 IU vitamin A per 100 kg body weight and day (35.7 mumol per kg fresh matter of liver). The vitamin A concentration of blood is unsuitable for evaluation of vitamin A status of cattle. The carotene content of feeds and level of vitamin A supply determined the carotene concentration of blood. Recommendations for a suitable vitamin A supply of ration of growing cattle were given depending on body weight and type of diet.  相似文献   

15.
Three groups of six pigs each (live weight at the beginning of the experiment 20 kg) were given a cereal ration with 8% rape seed meal. Group I did not receive a J supplement and was fed ad libitum. The rations of groups II and III were supplemented with 1 mg J/kg feed. The feed intake of group II was limited to the amount consumed by group I (pair fed); group III received the feed ad libitum. The daily weight gains of the 3 groups were 327, 377 and 613 g, feed expenditure 3.79, 3.68 and 3.47 kg/kg gain. In an N balance experiment carried out with 3 animals each from groups I and II, 41.4% of the N taken in group I and 43.8% in group II were retained (p greater than 0.05). Liver, intestinal fat and leaf were heavier in group I (p less than 0.01), the protein content of the empty body, the bones and bristles significantly lower than in group II. Protein retention in group II was 14% higher than in group I. In case of iodine deficiency protein retention is lower, energy retention, however, is largely unchanged.  相似文献   

16.
In six experiments with laying hybrids the influence of a varied nutritive beta-carotene and vitamin A supply during rearing on the performance in the laying period was tested. Basal rations poor in carotene without vitamin A supplementation in the rearing period diminished feed intake and laying performance in the laying period, retarded the beginning of intensive laying and increased feed expenditure per 100 g egg if the feed for laying hens contained less than 5000 IU vitamin A per kg. Relations between varied vitamin A supply and the performance parameters of the laying performance could not be proved if chick and young hen feed with maize even without vitamin A supplement or if rearing feed with approximately 2500 IU vitamin A or laying hen feed greater than 5000 IU vitamin A supply were used.  相似文献   

17.
Five experiments with 18 to 36 male calves each of the black and white dairy cattle breed (age: 14-21 days, initial live weight: approximately 45 kg per animal) were carried out in order to investigate the influence of various vitamin A supply (0-80,000 IU per 100 kg LW and day) on dry matter intake and weight gain as well as the vitamin A status of liver and blood plasma over 84 days. The calves consumed a diet free of carotene and vitamin A consisting of milk replacer, concentrate and chopped wheat straw. The calves were fed in three experiments for a longer time in order to observe the further vitamin A depletion. Nine animals consumed an unsupplemented ration, nine other one got 10,000 IU vitamin A per 100 kg LW and day. Biopsies of liver and plasma samples were taken from 4 animals per group every four weeks. The various vitamin A supplementation did not significantly influence the dry matter intake (Mean: 1.67; 1.48 to 1.80 kg DM per animal and day) and the weight gain of calves (Mean: 702, 599 to 770 g per animal and day). First vitamin A deficiency symptoms (reduced feed intake, decreased weight gain, diarrhoea etc.) were observed in animals of unsupplemented group after 100 days of experiments. After 84 days the vitamin A concentration of liver of animals of unsupplemented groups decreased to 1.3-32.2% compared with the begin of experiments (60.6-155.7 mumol/kg fresh matter). Up to 51% of initial concentration were found when 10,000 IU vitamin A per 100 kg LW and day were fed. About 25,000 IU vitamin A per 100 kg LW and day were required in order to keep the initial level of vitamin A concentration of liver. The plasma vitamin A concentration is unsuitable for estimation of vitamin A status of calves. The concentration of vitamin A of liver and plasma amounted to 114 mumol per kg and 0.25 mumol per litre at the begin of experiments. The vitamin A concentration of liver of unsupplemented group decreased to 20 mumol per kg, that of plasma increased to 0.28 mumol per 1 at the end. A strong vitamin A deficiency (liver concentration: less than 10 mumol/kg) may cause a decrease of vitamin A concentration of blood.  相似文献   

18.
10 castrated pigs each of a live weight (LW) of 35 kg and 115 kg were fed over 28 and 40 days resp. in a way that a live weight equilibrium was achieved. The pigs were kept individually and at a low mobility on perforated floors of zinc-plated sheet iron at an air temperature of 19 degrees C. The weighing 35 kg received 668 kJ ME/kg LW 0.75 per day and one half of the animals weighing 115 kg 635 kJ ME/kg LW 0.75 in a diet consisting of barley and bran. The other half of the animals weighing 115 kg received 514 kJ ME/kg LW 0.75 per day in a ration consisting barley, bran and dried skim milk. The crude protein content of the rations was 12.6 and 17.1% resp. of the DM, the crude fibre content amounted to 8-10% of the DM. Energy excretion in faeces and urine was calorimetrically measured. Up to the end of the experiment LW and the weight of the empty body (without ingesta) remained unchanged. For the measuring of energy retention, 4-5 zero animals each were analysed before the experiments. The pigs weighing 35 kg showed a daily loss of 39 g fat in the course of the 40-day experiment. The calculation of the energy balance showed that an intake of 790 kJ ME/kg LW 0.75 was necessary. This maintenance requirement, rather high in comparison with values from literature, can be explained with the emission of body heat on sheet iron floors and a crude fibre content of 9% in the rations. The pigs of the two groups of 115 kg LW were at an energy equilibrium at both nutrition levels. The lower maintenance requirement of the group fed with dried skim milk cannot exclusively be explained by the higher energetic utilization of the milk protein in the ration. The reason should be the more advanced age of the animals of the milk group. Although they had nearly the same live weight, their empty bodies contained 41% fat, the pigs of the barley/bran group, however, only 34%, both before and after the experiment.  相似文献   

19.
Studies were made with a total of 272 fattening pigs. Iodine deficiency both in rations of soya bean meal and rape seed meal increased the weight of the thyroid gland and the height of the epithelium cells and significantly reduced the T4 and T3 level in the serum. Iodine supplements to the rape seed meal rations distinctly diminished the goitrogenic effect, did not, however, cancel it out. Stage of goiter and depression of consumption were--different shown by the T3 and T4 level in the serum. Highly significant relations were calculated between live weight gain, weight and the height of the epithelium cells on the one hand and the T4 level in the serum on the other. Iodine supplementations of rations without thyrostatic components should amount to greater than or equal to 0.1 mg/kg. Iodine supplementations of 0.5 mg/kg feed are at present recommended to rations with rape seed meal quotas of less than 8%.  相似文献   

20.
The vitamin E requirement of growing pigs was estimated on the basis of prevention of morphological signs of deficiency. Five groups of pigs were fed a barley-based diet low in vitamin E that contained 16 mg of DL-alpha-tocopheryl acetate equivalents/kg and .1 ppm of Se for 4 wk (depletion I). This period was followed by 7 wk of supplementation, during which the groups received 0, 15, 45, 135 and 405 mg of supplemental DL-alpha-tocopheryl acetate/kg diet. Finally, all the animals were fed the low vitamin E diet for 7 wk (depletion II). To follow the vitamin E concentration in serum and tissues, blood samples were collected and biopsies were taken from skeletal muscle, adipose tissue and the liver throughout the experiment. The peak vitamin E value was observed in the liver, followed by the adipose tissue and then skeletal muscle. The liver responded rapidly to changes in dietary vitamin E intake, whereas the adipose tissue and the skeletal muscle reacted at a slower rate. In spite of the abundant occurrence of the different vitamin E isomers in the feed, alpha-tocopherol was the main isomer detected both in the serum and in the tissues. The activity of glutathione peroxidase in serum increased with age but was independent of the serum vitamin E concentration. In the unsupplemented group all animals suffered from the vitamin E and Se deficiency syndrome (VESD) in an acute or chronic form. A total of 31 mg of DL-alpha-tocopheryl acetate/kg diet (16 mg of naturally occurring vitamin E and 15 mg as supplementation) equivalent to 2.5 IU vitamin E/g polyunsaturated fatty acids (PUFA) was enough to prevent the development of VESD. In view of the large individual variations of vitamin E concentration in target organs, and to obtain a certain safety margin for prevention of VESD in growing pigs, a supplement of 30 mg of DL-alpha-tocopheryl acetate/kg diet is recommended.  相似文献   

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