Protein value of a new genotype oat (CDC SO-I) for the NRC dairy model: Protein degradation balance and kinetics, protein fractions and total metabolizable protein supply

2008 ◽  
Vol 88 (3) ◽  
pp. 507-513 ◽  
Author(s):  
P. Yu ◽  
B. G. Rossnagel ◽  
Z. Niu
Keyword(s):  
Small Intestine ◽  
Dairy Cattle ◽  
Protein Degradation ◽  
Western Canada ◽  
Microbial Protein ◽  
Normal Variety ◽  
In Situ Techniques ◽  
Metabolizable Protein ◽  
New Genotype ◽  
Protein Supply

Recently, a new genotype of oat has been developed specifically for feed purposes by the Crop Development Centre called CDC SO-I (“SuperOat”) containing a low-lignin hull and a high-fat groat. However, no quantitative evaluation of protein supply from CDC SO-I to dairy cow has been done in terms of potential protein degradation balance (PDB) and total metabolizable protein (MP) supply. These data are crucial in order to develop more efficient, competitive and optimal feeding the new genotype of oat (CDC SO-I) for livestock. Unlike DVE/OEB, PBI, ARC and NKJ-NJF models, NRC-2001 is a total digestible nutrient (TDN-) based model which is more popular in North America. The objectives of this study were to use the NRC model with inputs based on laboratory and in situ techniques to predict the potential nutrient supply to dairy cows from CDC SO-I in comparison with two conventional oat varieties, CDC Dancer and Derby, in western Canada. The quantitative predictions were made in terms of: (1) Rumen-synthesized microbial protein truly absorbed in the small intestine (AMCP); (2) Rumen undegraded feed protein truly absorbed in the small intestine (ARUP); (3) Endogenous protein in the digestive tract (AECP); (4) Total metabolizable protein supply in the small intestine (MP), and (5) Protein degraded balance (PDB). The results show that using the NRC model, the predicted PDB and total MP supplies to dairy cattle were significantly increased from the newly developed genotype of oat (CDC SO-I). Compared with the normal oat, CDC Dancer, CDC SO-I significantly increased (P < 0.05) ARUP, by 24%, and total MP supply by 9%, but did not change (P > 0.05) AMCP, AECP and PDB, with averages of 55.7, 4.5 and -11.96 g kg-1 dry matter (DM), respectively. Compared with the normal variety, Derby, CDC SO-I significantly increased (P < 0.05) AMCP, by 19%, total MP supply by 13% and increased PDB by 114%, but did not change (P > 0.05) ARUP and AECP values with averages of 19.2 and 4.5 g kg-1 DM, respectively. In conclusion, CDC SO-I oat increased total absorbed metabolizable protein supply to dairy cattle by 9–13% in comparison with the two conventional oat varieties used in western Canada. However, although CDC SO-I improved protein degraded balance, it still had a negative value (-10.6 g kg-1 DM), indicating the potential imbalance between microbial protein synthesis from available rumen-degradable crude protein (CP) and potential energy from fermentation in the rumen. Key words: TDN-based model, dairy cattle, oat genotype, protein degradation balance, metabolizable protein supply

Determination of nitrogen degradability of some different protein sources by in situ techniques

1999 ◽  
Vol 1999 ◽  
pp. 92-92
Author(s):  
M. Gorgulu ◽  
L. Baykal ◽  
H.R. Kutlu ◽  
C. Atasoglu
Keyword(s):  
Amino Acids ◽  
Small Intestine ◽  
Protein Degradation ◽  
Microbial Growth ◽  
Rumen Fermentation ◽  
Protein Sources ◽  
In Situ Techniques ◽  
The World

The rate and extent of protein degradation in the rumen is very crucial, as it determines the availability of nitrogen to microorganisms and amino acids in the small intestine to the host animals. The protein consumed by the animal should be partly degradable in the rumen, as peptides and amino acids derived from proteolysis are thought to stimulate microbial growth and rumen fermentation under certain conditions. It is, therefore, very important to determine the degradability of different feed ingredients which are grown and used in different regions of the world. The present study was undertaken to assess the degradation characteristics of different protein sources grown and used in Turkey.

scholarly journals Effect of the roughage/concentrate ratio on nitrogen entering the small intestine of dairy cows.

1981 ◽  
Vol 29 (4) ◽  
pp. 273-283
Author(s):  
S. Tamminga
Keyword(s):  
Protein Synthesis ◽  
Organic Matter ◽  
Small Intestine ◽  
Dairy Cows ◽  
Microbial Protein ◽  
Crude Fibre ◽  
Microbial Protein Synthesis ◽  
Digestible Organic Matter ◽  
Protein Supply ◽  
Microbial N

The effect of different roughage:concentrate ratios on N entering the small intestine was studied in groups of 2 to 5 cows with a rumen fistula and re-entrant cannulae at the beginning of the small intestine. In 3 series there were 10 treatments in which DM intake ranged between 3.8 and 15.7 kg daily; the proportion of long roughage in the diet was from 29 to 81%. The apparent digestibility of organic matter (O), crude fibre (XF) and nitrogen-free extracts (XX) was 76, 69 and 81%, respectively. The proportion of the digestion taking place in the stomach was 59, 94 and 76%. A larger proportion of the apparently digestible organic matter tended to be digested in the stomach when there was a larger proportion of long roughage in the diet. The contribution of microbial N to the intestinal N was estimated. From this the efficiency of microbial protein synthesis was estimated and related to the amount of carbohydrates (XF + XX) fermented in the stomach. Per kg carbohydrates fermented, 32 plus or minus 1.5 g microbial N was produced. The percentage of dietary N not degraded in the stomach averaged 30 plus or minus 1.5. Varying the ratio between long roughage and pelleted concentrates seemed to have little effect on the degradation of dietary protein or on the efficiency of microbial protein synthesis. With long roughage in the diet between 29 and 81% there seems little effect of varying the roughage:concentrate ratio on the protein supply in dairy cows. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals Influence of Small Intestinal Protein on Carbohydrate Assimilation in Beef and Dairy Cattle

1995 ◽  
Author(s):  
David L. Harmon ◽  
Israel Bruckental ◽  
Gerald B. Huntington ◽  
Yoav Aharoni ◽  
Amichai Arieli
Keyword(s):  
Small Intestine ◽  
Dairy Cattle ◽  
Critical Role ◽  
Starch Digestion ◽  
Peripheral Tissues ◽  
Critical Data ◽  
Intestinal Protein ◽  
Small Intestinal ◽  
Protein Supply

The long term goal of the proposed research, "Influence of small intestinal protein on carbohydrate assimilation and metabolism in beef and dairy cattle" was to define the limits of small intestinal starch digestion and clarify regulatory mechanisms involved in starch assimilation in cattle. It was hypothesized that dietary protein plays a critical role in the regulation of intestinal digestion; however, studies clearly identifying this role were lacking. The first two experiments quantified starch digestion (disappearance from the small intestine) in response to known increments in duodenal protein supply and found that the quantity of DM, OM and starch disappearing from the small intestine increased linearly (P <.01) with protein infusion. A follow-up experiment also demonstrated that casein infusion linearly increased pancreatic a-amylase concentration and secretion rate. The final experiment provided critical data on metabolic fates of glucose derived from intestinal starch digestion. These data demonstrated that increasing postruminal starch supply does increase the metabolism of glucose by visceral tissues: however, this increase is minor (20%) compared with the increase in portal production (70%). These changes can have a dramatic impact on the glucose economy of the animal and result in large increases in the amount of glucose reaching peripheral tissues.

Sign in / Sign up

Export Citation Format

Share Document