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221.
J Redlich W B Souffrant J P Laplace U Hennig R Berg J M Mouwen 《Canadian journal of veterinary research》1997,61(1):21-27
Ileo-rectal anastomosis (IRA), which is frequently used to measure prececal digestibility in pigs, could induce some disturbances of the normal absorptive function. Our aim was to investigate the effects of different IRA surgical procedures on the main histologic characteristics of the small intestine in pigs. The 4 different IRA procedures compared to intact pigs (INT) were the following: either end to end (EE) or end to side (ES) with or without preservation of the ileocecal valve (EEV, EE, ESV, ES respectively). At 147 d after surgery, samples of the wall of the duodenum, jejunum and ileum were taken under anesthesia and histometric examinations were performed on HE- and PAS-colored sections to estimate changes mainly of mucosa and muscle layers. The values recorded for villus length, crypt depth, and whole thickness of the mucosa suggested that the EE procedures disturb the small intestine less than the ES models. A new parameter, called epithelial quotient and calculated as [(villus length/crypt depth)/mitotic index], was proposed to improve the comparisons. According to this quotient, EE procedures did not significantly affect the mucosa of the whole small intestine. An increased density of goblet cells was recorded in all operated pigs along the small intestine, but mainly in the ileum after EE-IRA. The lymphatic follicle area was reduced. These findings, which were in agreement with a reduced mitotic index in the ileum of EE-pigs, indicated a decreased effect of noxious factors on the small intestinal mucosa in IRA-pigs, especially after the EE-IRA procedure. Some atrophic or hypertrophic effects on the muscle layers were related to the absence or preservation of the ileo-cecal valve. Finally it was concluded that i) there was no major disturbance after IRA, and ii) the end to end procedure was most beneficial for the structural integrity of the small intestine. 相似文献
222.
In two feeding experiments fattening bulls received on average a daily supplement of 170 or 200 mg Monensin. In a further 8-week experiment the daily Monensin supplement was 0; 500 or 1 000 mg per day. Ergotropic Monensin supplements (experiments 1 and 2) did not change the blood count and the Ca, P and Mg content of blood serum and the activity of AP, AST and LAP in the serum remained unchanged. Net acid base excretion and the content of Na, K and Mg in urine were not significantly influenced either. The influence of 500 mg Monensin per animal and day on the feed intake of animals previously given lower supplements was insignificant. 1 000 mg Monensin per animal and day resulted in a 40% decrease of feed intake and permanent diarrhoea. It was connected with a diminishing of the glucose content in the blood and an increase of net acid base, Na and P excretion in urine. The blood count did not change after the Monensin overdose. In conclusion one can say that the ergotropic Monensin supplement did not change the metabolism parameters. 相似文献
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In a multi-generation experiment with 120 hens of the species White Leghorn per group kept in cages, the influence of 5%, 7.5% and 15% 'fermosinR' torula yeast in the ration of mixed feed on various performance parameters in the 364-day laying period was investigated under long-term toxicologic aspects. In all probability there is no indication of toxic influences. The compatibility of the biomass can be considered good provided the basic nutrition-physiologic demands are met. 相似文献
226.
Generally, the faeces of laying hens fed 15N casein rations were found to contain equal proportions of TCE-precipitable and TCE-soluble nitrogen. Considerable variations were observed to occur between the 64 samples investigated (27%-75%) and no explanation was found to account for this fact. The content of basic amino acids in faecal proteins was found to differ considerably from that of the proteins in the intestinal contents. A high lysine content was found after the feeding of wheat. The present trial substantiated this result, provided the casein contained a certain proportion of non-available lysine. The apparent and true digestibility of dietary N was 88% or 91%, that of 15N (2nd and 6th day of experiment) and 92%. During the feeding of labelled casein a higher level of N labelling was found in the TCE-soluble portion of the faeces, whereas on the 8th to 12th day a higher level of labelling was observed in the TCE-precipitable portion of the faeces. The peak of 15N excretion occurred on the 3rd day of experiment. When 15N administration terminated the atom% 15N in the faeces and in urine was found to decrease rapidly approximating the initial level of labelling asymptotically. 相似文献
227.
Groups of male and female Cairina ducks subjected to equal starter feeding (1st to 3rd weeks) were used from the 4th week of live (fattening period) to test feed mixes of varying energy and crude protein levels (480 energetic feed equivalents/heu[EFH] - 140 g crude protein[CP]; 480 EFh - 180/g CP; 555 EFh - 140 g CP; 555 EFh - 180 g CP; 625 EEh - 140 g CP; 625 EFh - 180 g CP - all figures referred to 1 kg of feed). The different energy levels remained without influence of the live weight development. High-energy feed caused, however, higher expenditures of energetic feed equivalents per kg of gain and resulted in carcases with higher fat proportion. At all the 3 energy levels under study, high-protein feeding proved superior to low-protein rations with regard to live weight gains and meat yield. For the time being, 500 EFh and 180 g CP per kg of organic matter are recommended as indicators for Cairina duck fattening rations. 相似文献
228.
The present study included 2 trials which were performed to investigate in which way graded vitamin B6 supplies or vitamin B6 deficiency would influence the chemical composition of the whole body, the liver, pectoral muscle or the eggs of hens and in which way it might change the pattern of amino acid composition in the proteins of the pectoral muscle. The following results were obtained: No direct changes in the protein and fat content of the birds (total body, liver, pectoral muscle) were noted in trial 1 when graded amounts of vitamin B6 were supplied, whereas in trial 2 signifikant increases in the fat content of the body and decrases in the protein levels were observed when vitamin B6 supplements were added to a vitamin-deficient diet (pair-fed group) or fed to animals receiving increased amounts of food (controls). Variations in dietary vitamin B6 concentrations did not produce statistically significant changes in the protein and fat content of eggs, and in the pattern of amino acid composition of proteins in the pectoral muscle. However, with increasing vitamin B6 uptake, the serine to glycine ratio was narrowed. 相似文献
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J Wünsche M Meinl U Hennig E Borgmann F Kreienbring H D Bock 《Archives of Animal Nutrition》1987,37(2):169-188
In addition to a basic ration (barley, dried green fodder, fishmeal) pigs (castrated males, 100 ... 130 kg live weight) received a supplement of raw potato starch, raw ensiled potatoes, cooked potato starch or steamed ensiled potatoes; nutrient and amino acid passage and digestibility (absorption) were measured in the small intestine, the upper large intestine and the total digestive tract with the help of simple cannulae at the distal ileum and the middle of the hind gut and the estimation of the HCl insoluble ash as an indicator. In addition, the amounts of bacteria in faeces were determined and the influence of raw and cooked potato starch on N retention was ascertained. When raw potato products were fed, distinctly higher amounts of dry matter, organic matter and starch pass the ileum, which get into the colon undigested, i.e. the digestibility of these substances is low at the end of the ileum (raw potato starch 24%, starch of raw ensiled potatoes 36%). Up to the middle of the colon there is intensive bacterial starch degradation so that in this place the difference between raw and thermically treated potatoes is only small. No matter what the previous treatment of the potatoes was, there is hardly any starch in faeces, i.e. it was nearly 100% digested up to the end of the digestive tract. The passage and digestibility resp. of ash and crude cellulose from the basic ration is not influenced by the supplement of raw or thermically treated potato products in the individual sections of the digestive tract. At the end of the ileum there are no differences between the apparent digestibility of the crude protein and absorption of amino acids of supplemented raw or cooked potato starch or steamed ensiled potatoes; after the use of raw ensiled potatoes they are, however, significantly more reduced than the comparison of analyses of faeces shows. In the large intestine the high amount of potato starch stimulates the metabolism and the reproduction of faecal bacteria as is shown by an increase by 20-30% in bacteria N excretion in faeces. Apparent crude protein digestibility and amino acid absorption are diminished by that. The increased N excretion in faeces after the supplement of raw potato starch to the basic ration is-in comparison with the supplement of heated starch-compensated by a commensurately lower N excretion in urine so that N retention practically remains uninfluenced by the supplement of variously treated potato starch.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献