Activity of Digestive Enzymes in Chicken’s 
 Small Intestine and Caeca: Effect of Dietary Protein and Carbohydrate Content

Four castrated pigs, each fitted with a re-entrant cannula in the terminal ileum, were used to study digestion in the small intestine. A nitrogen-free diet was used for the estimation of metabolic nitrogen and amino acids. Faba beans, as the sole source of dietary protein, were used raw or after autoclaving for 30 or 60 min. The four diets were fed to the pigs in a 4 × 4 latin square experiment. The pigs were fed each diet for 6 days prior to a 24-hr collection of total ileal contents. Autoclaving of faba beans had no significant effect on digestibility of dry matter, gross energy, nitrogen and individual amino acids except arginine, which was significantly increased. The intestinal uptake of arginine was the highest and of cystine the lowest in all faba bean diets. It was concluded that autoclaving faba beans had no beneficial effect on the digestion of nutrients in the small intestine of the pig.

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The effect of protein- and non-protein-nitrogen supplements to maize silage on total amino acid supply in young cattle

British Journal Of Nutrition ◽

10.1079/bjn19820138 ◽

1982 ◽

Vol 48 (3) ◽

pp. 527-541 ◽

Cited By ~ 37

Author(s):

B. R. Cottrill ◽

D. E. Beever ◽

A. R. Austin ◽

D. F. Osbourn

Keyword(s):

Amino Acids ◽

Small Intestine ◽

Amino Acid ◽

Dietary Protein ◽

Fish Meal ◽

Metabolizable Energy ◽

Low Energy ◽

Maize Silage ◽

Protein Nitrogen ◽

Microbial N

1. A total of six diets based on maize silage were formulated to examine the effect of protein- and non-protein-nitrogen, and energy supplementation on the flow of amino acids to the small intestine and the synthesis of microbial amino acids in the rumen of growing cattle. All diets contained 24 g totai nitrogen (N)/kg dry matter (DM), of which 550 g N/kg total N was supplied by either urea or fish meal. Four diets contained low levels of barley (estimated total dietary metabolizable energy content of 10·4 M J/kgDM) and urea-N and fish meal-N were supplied in the ratios 3:1, 1·4:1, 0·6:1 and 0·3:1. The other two diets contained between 300 and 400 g barley/kg total diet (11·3 MJ metabolizable energy/kg DM) and the urea-N to fish meal-N ratios were 3:1 and 0·3:1.2. On the four low-energy diets, fish meal inclusion tended to reduce the extent of organic matter (OM) digestion in the rumen but significantly increased duodenal amino acid supply (P< 0·05) in a quadratic manner. Microbial-N synthesis was increased by the two intermediate levels of fish meal supplementation but declined at the highest level of inclusion. With increasing levels of fish meal inclusion, a greater proportion of the dietary protein was found to escape rumen degradation and the apparent degradabilities of fish meal and maize-silage protein of all four diets were estimated to be 0·22 and 0·73 respectively.3. The substitution of barley for part of the maize silage enhanced duodenal supply of amino acids, irrespective of the form of the N supplement, and stimulated microbial amino acid synthesis. For all diets efficiency of microbial-N synthesis was found to vary between 22·5 and 46 g N/kg rumen-digested OM. Contrary to what was found for low-energy diets, the inclusion of fish meal tended to reduce the flow of dietary protein to the small intestine, but these differences were not statistically significant.4. The results appertaining to microbial synthesis, dietary protein degradabilities and duodenal amino acid flow for all diets are discussed in relation to the Agricultural Research Council (1980) proposals for the protein requirements of ruminants, and the production responses observed when similar diets were fed to growing cattle.

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Effects of different dietary protein and lipids levels on growth performance and digestive enzymes of the rabbitfish (Siganus rivulatus), reared in well water

Egyptian Journal of Aquatic Biology and Fisheries ◽

10.21608/ejabf.2021.205026 ◽

2021 ◽

Vol 25 (5) ◽

pp. 645-660

Author(s):

Mohamed El-Sayed Salem et al.

Keyword(s):

Growth Performance ◽

Dietary Protein ◽

Digestive Enzymes ◽

Well Water ◽

Siganus Rivulatus

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Neurotensin stimulates growth of small intestine in rats

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1988.255.6.g813 ◽

1988 ◽

Vol 255 (6) ◽

pp. G813-G817 ◽

Cited By ~ 5

Author(s):

J. G. Wood ◽

H. D. Hoang ◽

L. J. Bussjaeger ◽

T. E. Solomon

Keyword(s):

Small Intestine ◽

Protein Content ◽

Digestive Tract ◽

Brush Border ◽

Digestive Enzymes ◽

Leucine Aminopeptidase ◽

Chronic Administration ◽

Equal Length ◽

Pancreatic Growth ◽

Proximal Small Intestine

Neurotensin has many actions on digestive tract motility and secretion and stimulates pancreatic growth. We examined effects of chronic administration of neurotensin on growth of small intestine and colon. Four groups of 10 rats were injected with saline or neurotensin (33, 100, or 300 micrograms/kg) every 8 h for 5 days. The small intestine was divided into four segments of equal length, weighed, and assayed for DNA, protein, and brush-border digestive enzymes. The colon was weighed and assayed for DNA and protein. Neurotensin caused dose-related increases in growth of small intestine; at the highest dose, similar increases in weight (12-20%), DNA (23-35%), and protein content (33-39%) occurred in each segment of small intestine. Maltase, sucrase, and leucine aminopeptidase (but not lactase) contents were also significantly increased after neurotensin, but the largest effects were seen in the proximal small intestine. Neurotensin had no effect on weight, DNA, or protein content of the colon. These results suggest a role for neurotensin in regulating growth of small intestine.

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