Blood serum ingredients and productive qualities of geese by triptophane level optimization in the diet during the period of intensive egg laying

Abstract

Based on the important metabolic action of tryptophan in animals and poultry, important scientific and practical interest are studies aimed at optimizing the level of this amino acid in diets.

A number of studies in recent years have shown that tryptophan is used in geese in the biosynthesis of nicotinic acid, serotonin, muscle proteins, hemoglobin, melatonin, required to ensure the physiological course of ovogenesis and spermiogenesis. Tryptophan normalizes the digestive and nervous systems, stimulates immune function.

It should be noted that today quantitative standards for this amino acid have been developed in the diets for different sex and age groups of geese, but domestic standards differ from foreign ones. However, in the scientific literature we have not found information on the metabolic and productive effects of optimized amounts of tryptophan in the diet of geese in such an important development period as intensive egg-laying.

Based on the above, the aim of our work was a comparative study of the effect of different amounts of tryptophan in the diet of geese during the reproductive period on changes in protein metabolism in the blood, their laying and incubation qualities of eggs.

The study was conducted on four groups of geese-analogues of Obroshynska gray breed group during 3-month laying period (January-March). For this purpose, 4 groups of geese were formed – analogues in age and live weight (in each group there were 4 geese and 1 goose). During the experiment period, geese of all groups received compound feed, balanced in nutrients, minerals and vitamins in accordance with norms, had free access to water. The control group did not receive synthetic tryptophan supplements. The level of this amino acid in this group was 0.16 g per 100 g of feed. To the diet of geese 2-, 3-, 4th experimental group was additionally introduced respectively 0.04; 0.09 and 0.14 g of synthetic tryptophan per 100 g of compound feed.

As a result of the conducted researches we found that the highest content of albumins in serum as well as α, β and γ-globulins was in the 3rd experimental group, in which it was respectively: 3.17; 0.31; 0.62 and 0.37%, which is 0.11; 0.04; 0.13 and 0.06% more than in the control. Regarding the level of amine nitrogen in the blood, it was 1.04% higher in the 3rd experimental group of geese than in the control.

Analyzing the performance of poultry, it should be noted that the average egg production of geese was slightly higher in the 2nd and 4th experimental groups compared to the control, and the highest – In 3rd experimental group and was 41.6 ± 0.9 pieces. The average weight of eggs in the 3rd experimental group of geese was 172.7 g, or 3.1 g more than in the control. The optimal index of egg shape was found in the 3rd experimental group of geese. The thickness of the eggshell in the experimental and control groups of geese did not change significantly.

Regarding such an important indicator as the hatchability of goslings, we found that it was the highest in the 3rd group (79.3%).

In general, the results of our studies show that increasing the level of tryptophan in feed from 0.16 to 0.25% during intensive egg laying optimizes the level of serum protein ingredients, improves the quality of hatching eggs, as well as hatchability and preservation of youngs.