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1.
In the experiment, 2 x 12 growing pigs received 19 or 6.7 mmol glucosinolates + aglucones/kg feed via conventional rapeseed meal (RSM) or RSM of a newly bred variety. These pigs and 24 littermates pair fed with a soya bean meal (SBM) diet were subdivided in groups of 4 animals each. Their diet contained either no supplementary iodine or an iodine supplementation of up to 1 mg/kg feed. In the RSM and SBM groups the lack of additional iodine lowered the serum T4 and T3 content below the detection limit and caused goitre with about 1 mg iodine in the total thyroid. The SBM diet with 0.0625 mg supplementary iodine/kg increased the serum T4 level and reversed the thyroid enlargement but not that of epithelial cells. The hypothyroidism (goitre and serum T4 level approximately 10 nmol/l) still existed in the case of this iodine dosage together with the RSM of the newly bred variety. A serum T4 level comparable to that of the animals fed SBM was only reached by supplementing the low glucosinolate diet with 0.25 mg iodine/kg feed. The iodine content of the thyroid, however, was reduced by 50 per cent. Though thyroid and epithelial cells were enlarged, this enlargement was not so obvious as in animals exposed to higher glucosinolate level. In spite of 1 mg supplementary iodine/kg feed, the feeding of the conventional RSM resulted in a lower serum T4 level a reduced thyroid iodine content and the enlargement of thyroid and that of epithelial cells. Compared to the high glucosinolate RSM, a significantly lower antithyroid effect of the low glucosinolate RSM was found in pigs with iodine supply. The degree of thyroid enlargement and the serum T4 level were the criteria.  相似文献   

2.
Since insufficient iodine intake is widespread among the German population, farm animals should if possible receive iodine above requirement, thus concentrating the trace element in milk, eggs and possibly meat. Experiments with a total of 29 fattening pigs with grain soy-bean meal diets without iodine supplementation or with increasing supplements up to 1000 micrograms iodine/kg diet did not show any effect on growth intensity (gain) and feed efficiency. At and above 125 micrograms supplementary iodine/kg diet the thyroid was not or only little hypertrophied and iodine incorporation into thyroglobulin sufficed to sustain serum T4 concentration. The glucosinolates of rape feeds increase iodine requirement. In an experiment with a total of 36 fattening pigs the thyroid iodine depot was decreased due to rapeseed meal feeding, this in agreement with antithyroid drugs which had been also tested. A thyroid with emptied iodine depot is hardly able to synthesize and release hormone, the serum thyroxine concentration showed a drastic decrease. More iodine may compensate for effects of glucosinolates, however, only with not too much of these compounds in the feed. Excessive iodine dosages (10 mg/kg diet) were compared with supplements in the range of recommendations (100 and 1000 micrograms/kg diet) with a total of 120 pigs in three groups of 40 animals each. The dosage of 10 mg iodine/kg diet decreased serum T3 concentration. The enlarged thyroid with double weight had a very high iodine concentration. In comparison with physiological application (100 or 1000 micrograms iodine/kg diet) the thyroid deposited only little iodine in the group with the excessive iodine intake related to consumed iodine quantity. In case of sufficient and excessive iodine supply--industry of compounds feed applies up to 2.5 mg supplementary iodine/kg diet--T4 and iodine of serum but also thyroid weight cannot serve as markers. This range of usual iodine supply is better characterized by the iodine depot of the thyroid. As a rule, thyroid weight increase indicates glucosinolate effects, generally those of dietary antithyroid compounds, more seldom it shows extreme and longterm iodine undersupply or iodine excess.  相似文献   

3.
In two experiments the effect of feeding dried crushed white and red grape press cake replacing 10--20% of the complex feed mixture A1 and SOL, was studied on the 21 biochemical indicators of blood serum, plasma, suprarenal glands, liver and tissue of fattened pigs. Changes indicating unsuitability of this non-traditional feed were not observed. During feeding red grape press cake, the young pigs of 35kg body weight had a lower concentration of glucose in blood serum, in comparison with the control. The temporary increase of calcium level and decrease of inorganic phosphorus in these animals was accompanied by a lower activity of alkaline phosphatase. White and red grape press cake affected positively the vitamin E level in blood serum. In the muscles of the experimental slaughter pigs protein proportion was increased and fat proportion was decreased.  相似文献   

4.
We investigated the effects of dietary copper and vitamin E in diets containing 6% rapeseed oil on the performance and the antioxidative and oxidative status of growing pigs. The 10 dietary treatments consisted of a basal diet (9 mg of vitamin E/kg feed, 15 mg of Cu/kg feed), the basal diet + 6% rapeseed oil (Diet 1; 18 mg of vitamin E/kg feed, 15 mg of Cu/kg feed), and Diet 1 plus supplements of vitamin E (0, 100, and 200 mg of dl-alpha-tocopheryl acetate/kg feed) and copper (0, 35, and 175 mg of Cu/ kg feed) in a 3 x 3 factorial arrangement of treatments. Eight or nine pigs were given ad libitum access to each diet from 25 to 100 kg of live weight. The inclusion of rapeseed oil tended (P < .10) to improve ADG and feed utilization. Compared with the addition of 35 mg of Cu/kg, the addition of 175 mg/kg improved growth rate and increased feed intake early in the experiment, but, over the total experiment, neither 35 nor 175 mg of Cu/kg affected performance. Compared with the addition of 100 mg of vitamin E/kg or no addition, the addition of 200 mg/kg reduced ADG over the total experiment (P = .05). The antioxidative and oxidative status of the pigs was evaluated in terms of blood and liver concentrations of antioxidants (alpha-tocopherol, ascorbic acid, vitamin A, superoxide dismutase, glutathione peroxidase), prooxidants (Cu), concentrations of lipids (triglycerides and cholesterol), fatty acid composition, thiobarbituric acid-reactive substances (TBARS), and clinical chemical (creatine kinase and glutamate-oxaloacetate-transaminase) and hematological variables that indicate the level of oxidative stress. There were no vitamin E deficiency signs or increased oxidative stress in pigs fed low dietary vitamin E levels, and no prooxidative effect of Cu was found. Increasing dietary levels of vitamin E increased the concentration of alpha-tocopherol in plasma and liver. Supplementation with Cu increased liver concentrations of Cu and alphatocopherol. The progression in liver TBARS was reduced by the addition of vitamin E and Cu. The addition of rapeseed oil changed the fatty acid composition of liver, increased alpha-tocopherol concentration in plasma and Cu concentration in liver, and reduced the rate of lipid oxidation in liver. In conclusion, even though the effects were minor, vitamin E, Cu, and rapeseed oil improved the antioxidative status of the live pigs.  相似文献   

5.
The experiment was carried out on 96 female broilers, allocated to eight groups of 12 birds kept in individual cages. Two basal wheat‐ and soyabean meal‐based diets containing 150 g/kg of rapeseed expeller cake were formulated, differing in the level of P: 7.1 g/kg in diet H or 5.9 g/kg in diet L. Rapeseed cake supplied 3.15 μmol alkenyl glucosinolates per gram of diet. The eight treatments were: basal diets only, basal diets + phytase (1000 U/kg), basal diets + organic acid blend (OA, 6 g/kg), or basal diets + both additives. Diets were fed from day 8 to 28 of life. The results showed that the lower dietary P content and OA supplementation did not significantly affect feed intake or BWG, while both increased (p < 0.001) after phytase supplementation. Tibia ash content as well as tibia ultimate strength were lower (p < 0.001) in birds fed diets L compared with diets H, and increased (p < 0.01) with phytase supplementation of diet L, while OA had no influence on either parameter. Dietary P levels and OA supplementation had no influence on the pH of gut digesta, but the pH of jejunal digesta increased following phytase supplementation (p < 0.01). Morphological measurements of the small intestinal mucosa of chicks indicated that OA added to diet L depressed villi height (p < 0.001) and crypt depth (p < 0.001); both parameters increased after phytase supplementation (p < 0.01). The lower total SCFA as well as acetic, propionic and butyric acid concentrations in caecal digesta indicated lower activity of caecal microflora in birds fed diets L compared with H. OA supplementation had no influence, while phytase supplementation increased the concentration of acetic acid in caecal digesta. Supplementation of diets with either phytase or OA increased thyroid weight by 16% (p < 0.01) and 11% (p < 0.05) respectively. The increase in thyroid weight because of phytase supplementation was greater at the lower dietary P level, and the greatest when both phytase and OA were added to the diet.  相似文献   

6.
An experiment was conducted to determine the effects of including cottonseed cake in rations for weaned growing pigs. Thirty-two Landrace x Large White pigs, weighing 20-24 kg, were included in four blocks formed on the basis of initial weight within sex in an otherwise completely randomized block design. The pigs were killed when they reached a live weight of 75.0 +/- 2.0 kg and the half carcases were analysed into cuts and the weights of the organs were recorded. An estimate of the productivity of the pigs on each diet was calculated. Cottonseed cake reduced the voluntary feed intake (p < 0.001) and live weight gains p < 0.001) and increased the heart, kidney and liver weights (p < 0.01). The pigs on the soya bean-based control diet took the shortest time to reach slaughter weight. The result was probably in part due to lysine deficiency and in part to the effect of free gossypol. It was found that it is at present cost-effective to include cottonseed cake in pig weaner-grower diets up to 300 g/kg in Cameroon.  相似文献   

7.
The aim of the present study was to assess the influence of different levels of iodine supplementation on animal growth and the iodine content of food from beef cattle. In a dose–response experiment with 34 growing fattening bulls of the “German Holstein” breed, in the range from 223 to 550 kg body weight, three iodine dosages were tested. The animals were fed a corn silage/concentrate ration. Iodine concentration in the diet amounted to 0.79 (Group 1), 3.52 (Group 2) and 8.31(Group 3) mg I per kg dry matter (DM). After slaughtering, I was determined in blood, serum, plasma, thyroid, liver, kidneys and meat (M. longissimus dorsi, M. glutaeus medius) by ICP-MS. I-supplementation did not significantly influence DM intake, daily weight gain (1453 (1), 1419 (2) and 1343 (3) g; p > 0.05) or slaughtering performance, but the weight of the thyroid gland increased significantly with the highest I dosage (32 (1), 26 (2) and 42 (3) g animal− 1, p < 0.05). I-supplementation significantly increased I-concentration in muscle, liver, kidney and thyroid gland (p < 0.05). The contribution of beef food to I-intake of humans is relatively low, therefore there is no need to reduce the EU-upper limit (10 mg kg− 1 feed) for growing fattening cattle from the view of consumer safety. In view of animal health and performance more dose–response studies seem to be necessary.  相似文献   

8.
Meat products with a higher iodine content can be produced through feeding animals with a diet supplemented with inorganic iodine salts or with algae containing high iodine. This may help to improve daily iodine intake and to control iodine deficiency disorders (IDD) in man. In the present study a total of 40 crossbred pigs (Deutsche Landrasse × Piétrain) with an average body weight of 17 kg were allotted to either a control group, to two groups receiving potassium iodide (KI) at different concentrations (5 or 8 mg iodine per kg of feed) or to two groups receiving the algae Laminaria digitata containing the same amount of iodine. After pigs were fed with iodine-supplemented diets for 3 months, it was found that compared to the control group the iodine content increased by up to 45% in fresh muscle, by 213% in adipose tissue, by 124% in the heart, by 207% in the liver and by 127% in the kidneys. There was a significant (p < 0.01) higher concentration of serum thyroxine (T4) and a lower concentration of serum triiodothyronine (T3) in those iodine-supplemented groups. The iodine content of urine from all iodine-supplemented groups was also greatly increased. Furthermore, it was shown that the supplementation of algae into feed could increase daily body weight gain by 10% (p > 0.05). It is suggested that the carry-over of iodine through feeding pigs with an algae-supplemented feed could be beneficial to both the control of IDD and the improvement of pig production.  相似文献   

9.
The effect of feeding dry feed (DF), nonfermented liquid feed (NFLF), and fermented liquid feed (FLF) to growing pigs on aspects of gastrointestinal ecology and on performance was investigated. Nonfermented liquid feed was prepared by mixing feed and water at a ratio of 1:2.5 immediately before feeding. Fermented liquid feed was prepared by mixing feed and water in the same ratio as NFLF, and stored in a tank at 20 degrees C for 4 d, after which half the volume was removed twice daily at each feeding and replaced with the same volume of feed and water mixture. A total of 60 pigs (initial BW of 30.7 kg) from 20 litters was used. Twenty pigs, housed individually, were allotted to each of the diets and fed restrictively. Five pigs from each diet were sacrificed at an average BW of 112 kg and digesta from the gastrointestinal tract (GI-tract) was obtained to examine variables describing some aspects of the gastrointestinal ecology. Fermented liquid feed contained high levels of lactic acid bacteria (9.4 log cfu/g) and lactic acid (approximately 169 mmol/kg), low levels of enterobacteria (<3.2 log cfu/g), and had a low pH (4.4). Nonfermented liquid feed contained 7.2 log cfu/g of lactic acid bacteria, and 6.2 log cfu/g of enterobacteria, which indicated that fermentation had started in the feed. The pigs fed FLF had the lowest levels of enterobacteria along the GI-tract (<3.2 to 5.0 log cfu/g), and those fed NFLF the highest levels (5.7 to 6.6 log cfu/g; P < or = 0.02). Fermented liquid feed caused a decrease in gastric pH from 4.4 and 4.6 for DF and NLF, to 4.0 (P = 0.003), and increased numerically the gastric concentration of lactic acid (P = 0.17) from 50 to 60 mmol/kg in the DF and NFLF treatments to 113 mmol/kg in the FLF treatment. The animals fed NFLF showed the highest weight gain (995 g/d) and feed intake (2.14 kg/d), and those fed FLF the lowest values (weight gain, 931 g/d; feed intake, 1.96 kg/d; P = 0.003 for weight gain, and P < 0.001 for feed intake). The results from the present study indicate that feeding FLF as prepared here may be a valid feeding strategy to decrease the levels of enterobacteria in the GI-tract of growing pigs, whereas feeding liquid feed that has started to ferment (high levels of enterobacteria and high pH as with NFLF) increases the presence of these undesirable bacteria. Nonetheless, higher daily feed intake and body weight gain are obtained when feeding NFLF compared with feeding FLF or DF.  相似文献   

10.
Supplementation of pigs with vitamin E, the most important lipid-soluble antioxidant, has been shown to improve meat quality and animal health. Previous studies in cultured cells and laboratory animals indicate synergistic effects between polyphenols and vitamin E. The present feeding trial was undertaken to investigate the effects of dietary green tea polyphenols (GTP) on vitamin E status, antioxidative capacity and parameters of meat quality in growing pigs. Eighteen castrated, crossbred, male pigs received a flavonoid-poor diet based on corn starch, caseinate and rapeseed oil with a total vitamin E content of 17 IU/kg diet over a period of 5 weeks. This basal diet was supplemented with green tea extract to provide daily doses of 0 (control), 10 and 100 mg GTP/kg body weight. Dietary supplementation of growing pigs with GTP did not affect serum, liver, lung and muscle vitamin E (α- and γ-tocopherol) concentrations, plasma antioxidant capacity (ferric reducing ability of plasma, trolox equivalent antioxidant capacity) or parameters of meat quality including meat temperature, pH, conductivity, colour and drip loss. In conclusion, supplementation of pig diets with green tea catechins is not associated with improved antioxidant status and meat quality under practice-oriented conditions.  相似文献   

11.
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   

12.
Vitamin E, selenium and polyunsaturated fatty acids (PUFAs) were determined in feed used at three piggeries over a four-week period and compared with corresponding concentrations in clinically normal grower pigs at slaughter. Mean values were vitamin E: 59 IU/kg (feed), 6 μmol/kg (liver), 1.7 μmol/1 (serum); and selenium: 310 μg/kg (feed), 5200 nmol/kg (liver), 1700 nmol/1 (blood). Alpha-tocopherol accounted for 80% of the mean vitamin E activity in the feed and over 95% that in the liver and serum. The mean ratio of PUFA to total fatty acid (FA) in the feed (38%) was similar to that in the serum (36%) and liver (39%), but the ratio of peroxidisable PUFA (PPUFA) to FA increased from 1.7% in the feed to 4.2% in the serum and 10.8% in the liver. The ratio of α-tocopherol (mmol) to PPUFA (mol) in the liver varied from 0.16 to 0.48. The relationship of these data to the “VESD” syndrome is discussed in the light of other published data.  相似文献   

13.
选取健康"杜×长×大"三元杂交生长猪36头,按饲养试验要求分为3组,每组3个重复,每重复4头猪(公、母各半)。对照组饲喂玉米-豆粕型日粮;试验1组(双低菜粕组)在对照组饲粮基础上,用8%的双低菜粕代以配方中7%的豆粕;试验2组(双低菜粕+酶组)在试验1组基础上添加0.03%专用复合酶制剂。预试期7 d,正试期32 d。结果表明,不同处理日粮对生长猪的生长和饲料利用无显著影响(P>0.05);添加酶制剂使生长猪血清FT3水平提高了17.01%(P<0.05);双低菜粕组生长猪血清IgA含量提高了14.08%(P<0.01),加酶后生长猪血清IgGI、gM、补体C3和C4含量分别提高了12.59%(P<0.01)、20.59%(P<0.01)、36.18%(P<0.01)和24%(P<0.01);不同处理日粮对生长猪血清抗氧化指标及Ca、P、BUN(尿素氮)含量均无显著影响(P>0.05)。  相似文献   

14.
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   

15.
(1) Apparent ileal and total tract protein digestibilities of rapeseed meal and cake and soybean meal and cake were assayed in growing turkeys at 4, 8 and 12 weeks of age. (2) In addition, the effect of killing technique on apparent ileal protein digestibility values obtained by a slaughter method and effect of rapeseed feeding on size of specific organs were studied. (3) Protein digestibility coefficients of rapeseed products were mostly 0.10 to 0.15 units lower than those of soybean products. Ileal digestibility of protein increased slightly or remained unchanged from 4 to 8 weeks and decreased thereafter. No effect of feed processing method (meal vs cake) on ileal digestibility was observed. (4) Killing the birds by carbon dioxide inhalation and bleeding led to slightly lower ileal digestibility values than mechanical stunning and neck dislocation. (5) Total tract digestibility of protein decreased from 4 to 8 weeks of age for soybean meal and rapeseed meal but increased for soybean cake and rapeseed cake. From 8 to 12 weeks of age total tract digestibility of protein decreased for all the products tested. (6) Feed containing rapeseed led to enlargement of thyroid glands and hearts, but did not affect liver size or mortality.  相似文献   

16.
Twelve pigs were subjected to model trials to study the effect of an aflatoxin-contaminated pig-fattening diet, administered for 26 days. Aflatoxin B1 constituted 55% of the aflatoxins tested. The aflatoxin concentrations used in the trials were 30 and 300 micrograms per 1 kg of feed. No clinical effect of aflatoxin was observed in the pigs. Aflatoxins were found to have adverse effects on proteosynthesis. A decrease in the weight gains of the pigs was accompanied by a decrease in the total plasma protein and, in the group with the higher aflatoxin dose (300 micrograms per 1 kg of feed), also by an increase in the total bilirubin concentration in the blood serum. Perilobular steatosis, dissociation of the liver trabeculae, and more pronounced activation of the reticuloendothelial system were demonstrated by the histological examination of liver tissue. An increase in the content of hydroxyproline was recorded in the muscle of the experimental pigs. It is documented by the results that the aflatoxin dose of 30 micrograms per 1 kg of feed (the recommended maximum admissible concentration for the Czech Socialist Republic) is high enough to reduce the performance of pigs and the biological value of their meat.  相似文献   

17.
Four diets were formulated with protein from fishmeal (FM), groundnut cake (GC), ensiled sweet potato (Ipomoea batatas L. (Lam.)) leaves (SP) or ensiled sweet potato leaves with lysine (SPL). In experiment 1, 24 crossbred (Large White x Mong Cai) growing pigs were allocated randomly by sex into four groups of six pigs and given one of four diets. Experiment 2 was conducted using 16 crossbred pigs (Large White x Mong Cai) at four farms. On each farm, pigs were allocated to two experimental groups. One group was fed the FM diet and the other group the SPL diet. In experiment 1, the daily live weight gains (DLWG) were significantly higher (p < 0.05) for the FM and SPL treatments (542 and 536 g/day, respectively) than for the GC and SP treatments (464 and 482 g/day, respectively). Feed intake was highest (2.0 kg/day) for the SPL and lowest (1.7 kg/day) for the GC treatment (p < 0.05) and feed conversion ratio (FCR) was highest (3.8 kg/kg gain) for SP and lowest (3.5 kg/kg gain) for FM (p < 0.05). There were no significant differences for carcase measurements among diets (p > 0.05). The feed cost per kg live weight gain was lowest for the SP and SPL diets compared to the FM and GC diets. The results of experiment 2 show that there were no significant differences in feed intake, DLWG and FCR between the two diets (p > 0.05). In conclusion, sweet potato leaves can replace fishmeal and groundnut cake in traditional Vietnamese diets for growing pigs.  相似文献   

18.
Eighty-five dairy cows of the Swedish Red and White Breed (SRB) were included in a long-term experiment during 3 consecutive lactations. The cows were divided into 3 different dietary groups that received no rapeseed (NR), up to 1.2 kg dry matter (DM) 00-rapeseed meal plus 0.2 kg DM full-fat 00-rapeseed (MR), and up to 2.5 kg DM 00-rapeseed meal plus 0.9 kg DM full-fat 00-rapeseed (HR) per day. No significant differences in culling rates or disease rates were found between the feeding groups at any time during the experiment. The interval from calving to conception among the primiparous cows was longer for the HR-group (125 days) than for the NR-group (100 days). The response to a thyrotroph releasing hormone around 90 days postpartum during the first lactation was significantly higher for the HR-group (86.7 µ/L/h) than for the NR-group (55.2 µg/L/h). This indicates that at the highest level of rapeseed feeding, glucosinolates had a very mild, suppressive influence on thyroid hormone release, apparently compensated for by an increased activity along the hypothalamic-pituitary-thyroid axis. No significant differences in fertility or thyroid function were found among the pluriparous cows. During 2nd lactation the concentration of serum urea was higher in the NR-group (7.31 mmol/L) than in the HR-group (6.83 mol/L). The effects of independent environmental factors influenced fertility and thyroid function to a much greater extent than the rapeseed feeding. It was concluded that the feeding of rapeseed products from certified double low varieties of B. napus to adult dairy cows in amounts up to 3 kg rapeseed meal per cow and day would not have any negative effects on animal health or fertility.  相似文献   

19.
A trial with the continual administration of feed contaminated with the Delor 103 preparation (polychlorinated biphenyls--PCB) at a rate of 75 mg per kg for chicks lasted four weeks. The concentrations of serum thyroxine and triiodothyronine were found to decrease, the concentrations of total calcium increased and at the Delor 103 doses of 150 mg per kg even the phosphorus concentration and the activity of alkaline phosphatase in the serum of chicks decreased. The addition of potassium iodide to feed (250 mg per kg) did not influence the clinical picture of Delor 103 intoxication. The results confirm a finding that in the course of PCB intoxication severe disorders of the thyroid gland take place and calcium metabolism is disturbed. This finding is important in view of evaluation of the intoxication of young, growing chicks.  相似文献   

20.
Vitamin E, selenium and polyunsaturated fatty acids (PUFAs) were determined in feed used at three piggeries over.a four week period and compared with corresponding concentrations in clinically normal grower pigs at slaughter. Mean values were vitamin E: 59 IU/kg (feed), 6 micromol/kg (liver), 1.7 micromol/l (serum); and selenium: 310 microg/kg (feed), 5200 nmol/kg (liver), 1700 nmol/l (blood). Alpha-tocopherol accounted for 80% of the mean vitamin E activity in the feed and over 95% that in the liver and serum. The mean ratio of PUFA to total fatty acid (FA) in the feed (38%) was similar to that in the serum (36%) and liver (39%), but the ratio of peroxidisable PUFA (PPUFA) to FA increased from 1.7% in the feed to 4.2% in the serum and 10.8% in the liver. The ratio of alpha-tocopherol (mmol) to PPUFA (mol) in the liver varied from 0.16 to 0.48. The relationship of these data to the VESD syndrome is discussed in the light of other published data.  相似文献   

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