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Microbial Protein (microbial + protein)
Terms modified by Microbial Protein Selected AbstractsEffect of fortifying concentrate supplement with fibrolytic enzymes on nutrient utilization, milk yield and composition in lactating goatsANIMAL SCIENCE JOURNAL, Issue 3 2009Prokasananda BALA ABSTRACT Thirty lactating Beetle-sannen crossbred goats were randomly divided into 3 groups based on first fortnight milk yield, and then adjusted to body weights to study the effect of fibrolytic enzyme supplementation on digestibility and milk production. Goats in the control group (C) were fed 500 g of concentrate supplement (CS) without exogenous fibrolytic enzymes (control; CG) or CS fortified with cellulase and xylanases @ of 4000 and 12500 (EG1) or 8000 and 18 750 IU/kg (EG2), respectively. CS was offered in two equal proportions just after milking at 7 and 17 h. After feeding CS, goats were fed 1200 g of wheat straw as roughage in two equal parts at 08.00 and 18.00 hours. Milk yield was studied for 3½ months. Milking was done by hand. Changes in body weight were also recorded. After a preliminary period of 60 days of feeding, a 7-day digestibility trial was conducted in two intervals with 5 animals from each group at a time. The increase in either wheat straw or NDF intake due to the enzyme mixture was only 3%. There was significant improvement (P < 0.05) in the diet digestibility of DM, OM, CP, NDF, ADF and total carbohydrates (TC) between the control and EG1 and EG2 goats. Improvements were greater (P < 0.05) in the latter group. Microbial protein (MBP) was estimated based on purine derivatives and creatinine excreted in spot urine samples. MBP increased about 10 and 15% in EG1 and EG2, but these values were statistically invalid. Phenomenally milk yield, fat and SNF were significantly (P < 0.001) changed with progression of lactation. On a temporal basis, fortnightly changes in FCM yield of this study could be grouped as 1 month each of first and last and 1½ of middle phase of lactation. Repeated measure analysis showed 180 to 260 mL/day of higher FCM and 16 to 20 g/day of higher SNF yield (P < 0.001) in EG2 than control or even EG1 during 5 to 7th fortnight. However, no significant impact (P > 0.05) was noticed on TF. Feed intake, g/kg FCM yield was also 7% less in EG2 than either CG or EG1. The study concluded that apart from increased digestibility, fortification of CS with cellulase and xylanases enzymes improved FCM yield in the last quarter of lactation in goats, and improved body weights by 5% (P > 0.05). While the digestibility of the diet was higher in EG1 and EG2, the impact on FCM and SNF yield was noticed only on EG2. Our study indicated that CS of lactating goats may be fortified with 8000 and 18 500 IU/kg CS in the last quarter of lactation. [source] Prediction of protein supply to ruminants from concentrates: comparison of the NRC-2001 model with the DVE/OEB systemJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 4 2005Peiqiang Yu Abstract The objective of this study was to compare the DVE/OEB system (DVE = truly absorbed protein in the small intestine; OEB = degraded protein balance) and the NRC-2001 model in the prediction of supply of protein to dairy cows from 46 selected concentrates: malting-type barley (cv Harrington), feed-type barley (cv Valier), field tick beans (Vicia faba), white albus lupins (Lupinus albus), whole soybeans and horse beans (Vicia faba cv Alfred). The two barleys were processed by coarse (roller miller, 0.533 mm gap) and fine (hammer mill, 2 mm screen) processing. The field tick beans and white albus lupins were dry roasted at various conditions at the University of Melbourne. The soybeans and horse beans were pressure-toasted at 100, 118 and 136 °C for 3, 7, 15 and 30 min at Wageningen Feed Processing Centre. Comparisons were made in terms of (1) ruminally synthesized microbial protein, (2) truly absorbed protein in the small intestine and (3) degraded protein balance, based on 46 samples. The results showed that the predicted values from the DVE/OEB system and the NRC-2001 model had significant correlations. However, using the DVE/OEB system, the overall average microbial protein supply based on available energy was 10% lower and the truly absorbed protein in the small intestine was 8% lower than that predicted by the NRC-2001 model. A difference was also found in the prediction of the degraded protein balances, which was 16% higher than that estimated from the NRC-2001 model. These differences are due to factors used in calculations in the two models, although both are based on similar principles. This indicates that further refinement is needed for a modern protein evaluation and prediction system. Copyright © 2004 Society of Chemical Industry [source] The integration of digestion and osmoregulation in the avian gutBIOLOGICAL REVIEWS, Issue 4 2009Todd J. McWhorter Abstract We review digestion and osmoregulation in the avian gut, with an emphasis on the ways these different functions might interact to support or constrain each other and the ways they support the functioning of the whole animal in its natural environment. Differences between birds and other vertebrates are highlighted because these differences may make birds excellent models for study and may suggest interesting directions for future research. At a given body size birds, compared with mammals, tend to eat more food but have less small intestine and retain food in their gastrointestinal tract (GIT) for shorter periods of time, despite generally higher mass-specific energy demands. On most foods, however, they are not less efficient at digestion, which begs the question how they compensate. Intestinal tissue-specific rates of enzymatic breakdown of substrates and rates of active transport do not appear higher in birds than in mammals, nor is there a demonstrated difference in the extent to which those rates can be modulated during acclimation to different feeding regimes (e.g. diet, relative intake level). One compensation appears to be more extensive reliance on passive nutrient absorption by the paracellular pathway, because the avian species studied so far exceed the mammalian species by a factor of at least two- to threefold in this regard. Undigested residues reach the hindgut, but there is little evidence that most wild birds recover microbial metabolites of nutritional significance (essential amino acids and vitamins) by re-ingestion of faeces, in contrast to many hindgut fermenting mammals and possibly poultry. In birds, there is some evidence for hindgut capacity to breakdown either microbial protein or protein that escapes the small intestine intact, freeing up essential amino acids, and there is considerable evidence for an amino acid absorptive capacity in the hindgut of both avian and mammalian hindgut fermenters. Birds, unlike mammals, do not excrete hyperosmotic urine (i.e. more than five times plasma osmotic concentration). Urine is mixed with digesta rather than directly eliminated, and so the avian gut plays a relatively more important role in water and salt regulation than in mammals. Responses to dehydration and high- and low-salt loads are reviewed. Intestinal absorption of ingested water is modulated to help achieve water balance in one species studied (a nectar-feeding sunbird), the first demonstration of this in any terrestrial vertebrate. In many wild avian species the size and digestive capacity of the GIT is increased or decreased by as much as 50% in response to nutritional challenges such as hyperphagia, food restriction or fasting. The coincident impacts of these changes on osmoregulatory or immune function of the gut are poorly understood. [source] Using a complex non-TDN based model (the DVE/OEB system) to predict microbial protein synthesis, endogenous protein, degradation balance, and total truly absorbed protein supply of different varieties of cereal oats for ruminantsANIMAL SCIENCE JOURNAL, Issue 3 2009Peiqiang YU ABSTRACT Recently a new super-genotype of oat has been developed in the Crop Development Center called CDC SO-I (,SuperOat': low lignin and high fat). In a previous study, we evaluated total metabolizable protein using a TDN-based model-NRC-2001 which is popular in North America. However, the TDN-based NRC model is not accepted universally. The objectives of this study were to use a complex non-TDN based model, the DVE/OEB system, to evaluate potential nutrient supply to ruminants from the SuperOat in comparison with two normal varieties of oats (CDC Dancer and Derby) in western Canada. The quantitative predictions were made in terms of: (i) truly absorbed rumen synthesized microbial proteins in the small intestine; (ii) truly absorbed rumen undegraded feed protein in the small intestine; (iii) endogenous protein in the digestive tract; (iv) total truly absorbed protein in the small intestine; and (v) protein degraded balance. Results showed that using the DVE/OEB system to predict the potential nutrient supply, it was found that the SuperOat had similar truly absorbed rumen synthesized microbial protein levels (61, 63, 59 g/kg DM, P > 0.05, for SuperOat, CDC Dancer and Derby, respectively), higher truly absorbed rumen undegraded feed protein than CDC Dancer (22 vs. 17 g/kg DM P < 0.05, for SuperOat, CDC Dancer, respectively), but similar to Derby (22 vs. 21 g/kg DM; P > 0.05), and similar endogenous protein (16, 16, 18 g/kg DM; P > 0.05). Total truly absorbed protein in the small intestine is only numerically higher in the SuperOat (67 vs. 65, 62 g/kg DM, P > 0.05, for CDC Dancer and Derby, respectively). However, the protein degraded balance was significantly different (P < 0.05) with a positive value for the SuperOat (7.0 g/kg DM) and negative values for two normal varieties (,1.5, ,6.8 g/kg DM for CDC Dancer and Derby, respectively). In conclusion, the model predicted significantly different protein degradation balance. The SuperOat had positive degradation balance but other two normal varieties had negative protein degraded balance However, the SuperOat had similar total absorbed protein value to the two normal varieties of oats. [source] Recovery and separation of cell lysate proteins using hydrogels guided by aqueous two-phase extraction principlesBIOTECHNOLOGY & BIOENGINEERING, Issue 2 2002Christopher S. Putka Abstract The addition of poly(ethylene glycol) and salts to clarified cell lysates of Thiosphaera pantotropha increases sorption of microbial proteins into dextran hydrogels, consistent with the thermodynamics of aqueous two-phase extraction. Addition of 12 wt% PEG-10,000 to the lysate increased total sorption of protein by the dextran gel from 5.2 mg/g dextran to 37 mg/g; addition of either 0.1 M potassium iodide or tetrabutylammonium fluoride along with PEG to the lysate increased protein sorption to more than 63 mg/g, a 12-fold increase. SDS-PAGE demonstrated that the type of salt added controls which proteins are absorbed by the gel. Previously demonstrated only with model solutions, these results suggest another approach to recovery and separation strategies for proteins produced by fermentation. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 80: 139,143, 2002. [source] | ||||||||||