Danuta Strusińska

Changes of Nitrogen Compounds During Ensiling of High Protein Herbages – A Review

Abstract Losses of crude protein during ensiling of herbages, in contrast to carbohydrates, do not affect the reduction of its content; their form is changed into greater solubility non-protein compounds and also highly degraded forms, which lower the efficiency of the microbial protein synthesis in the rumen. These processes are accompanied by a change of amino acid composition of herbage protein and decrease in intestinal digestibility of protein from feeds as a result of the formation of indigestible complexes with carbohydrates (ADIN). Reduction of protein degradation in silages is achieved by accelerated acidity through addition of acids or dominance of homofermentative bacteria. The positive effects of fermentation inhibitors or sorbents use, as well as the wilting of raw material on the level and rate of protein degradation were demonstrated by many researchers. A greater contribution of protein nitrogen and reduction of deamination in silages can also be obtained by using bacteria inoculants. Increasing the proportion of protein nitrogen is accompanied by the improved efficiency of microbial protein synthesis.

Effect of Diets Containing Grass Meal and Alfalfa Meal on the Content of Carotenoids, Vitamin A and Vitamin E in the Egg Yolk and Selected Reproduction Parameters in Geese

Abstract Puchajda-Skowrońska, H., Strusińska, D., Trojanowska, E. and Kozlowski, K. 2010. Effect of diets containing grass meal and alfalfa meal on the content of carotenoids, vitamin A and vitamin E in the egg yolk and selected reproduction parameters in geese. J. Appl. Anim. Res., 37: 191–195. To determine the effect of the carotenoid content of diets on the reproduction parameters of geese as well as on the accumulation of carotenoids and selected carotenoid fractions, and the content of vitamin A and vitamin E in the egg yolk in successive months of the laying season a breeding flock of geese in their first year of production (28-week-old) was randomly divided into two equal groups. The geese were fed isonitrogenous and isocaloric complete diets where the main source of carotenoids (including xanthophylls) was 20% grass meal containing 244 meg/g carotenoids and 175 meg/g xanthophylls in the first group and 20% alfalfa meal containing 187 meg/g carotenoids and 132 meg/g xanthophylls in the other group. Diets with a 20% grass meal content contributed to a significantly higher total content of carotenoids, in particular ethyl ester of β-apo-8′ carotenoic acid and citranaxanthin, in the egg yolk. The egg fertilization rate over the entire laying period was 16.69% higher in the group of geese fed a diet with higher carotenoid concentrations. Laying intensity was inversely correlated with the carotenoid content of the egg yolk. In the peak-laying months, the lowest retinol, tocopherol and carotenoid concentrations were noted in the egg yolk in both experimental groups.

Effect of Rumen Protected Methionine Supplementation on Early Lactational Responses of Dairy Cows Fed a Grass Silage and Cereals Diet

To investigate the milk production limiting potential of a diet based on grass silage (40%), hay (15%), dried sugar beet pulp (13%) and grain compound mixture (32%), 28 multiparous cows in early lactation were randomly assigned to two treatment groups: a control group and a group receiving supplementary rumen protected methionine (RPMet) treatment (12 g intestinally available methionine/cow/day, given 1-120 days postpartum; Smartamine; RPANs technology). The diet was formulated to meet the requirements for protein and net energy. RPMet supplementation had no significant effect on DMI (kg/cow/day), milk dry mass, milk lactose and milk urea contents. Responses for mean daily milk yield, mean milk fat and milk protein yields were significantly higher (P < 0.05) in cows supplied with RPMet than in controls. Mean daily milk yield, milk protein and milk fat yields increased by 2.4 kg, 108 g and 124 g, respectively. The mean daily milk protein and casein contents were increased by 1.8 g and 0.9 g and milk fat content by 1.2 g in 1 kg of milk, respectively. The results suggest that in cows fed grass silage and a grain compound mixture milk production is limited by methionine insufficiency, but milk production performance can be increased significantly by the addition of RPMet to the diet.