Effect of different levels of protein in feed on immunity of broiler chickens in ontogenesis

УДК 636.5.033/59.083
DOI 10.33861/2071-8020-2024-1-21-24

Ovchinnikova N. V., Kuzmina I.V.

Summary. Studies were conducted to investigate the effect of different levels of protein (23.0%; 21.5% and 24.5%) in the feed on hematological parameters of broiler chickens blood. Experiments were carried out on 105 Smena 9 cross broiler chickens from daily to 35 days of age. Crude protein in the diet was changed by changing the proportion of soybean meal and synthetic amino acids in the period from daily to 14 days of age. Blood for the study was obtained weekly from 5 head from each group. At 24 and 7 days of age - at slaughter. In other age periods - from the umbilical vein. When adding different levels of protein to the diet, differences in the number of leukocytes were observed, namely, in experimental group 1 this indicator was lower than in control and experimental groups 2. In all investigated groups there is a tendency to increase erythrocytes with age. When varying different levels of protein in the diet in both experimental groups, the values of this indicator were lower relative to the control group. Heterophiles (Het) are the predominant cell type in the leukocytic blood formula at the daily age, from the 7-day age the lymphocytic (Lym) blood profile is established, in 21 (experimental groups) - 28 (control group) days the so-called ‘physiological crossroads’ of the leukocytic blood formula of broilers occurs. Our experiment revealed a sharp jump of monocytes (Mon) in the experimental 2 group at 7- and 21-day-old in 7 (p<0.05) and 2.6 times (p<0.05), respectively, exceeding the values of the control group. The change in the number of eosinophils (Eos) occurred in a wave-like manner in all groups. At the age of 28 days, there was an increase in the number of basophils (Bas) by 50% in the control and experimental group 1 (p<0.05), and in experimental group 2 (p<0.05) at 35 days of age. Based on the above observations, we concluded that the change in the ingredient composition of feed in the first two weeks of rearing affects the morphological indices of blood of broiler chickens.

Keywords: broiler chickens, protein, immunity, erythrocytes, leukocytes, hemoglobin, hematocrit, heterophils, lymphocytes, monocytes, basophils, ontogenesis.

References:

1. Vertiprakhov V. G. et al. Morfobiokhimicheskie issledovaniya krovi u selskokhozyaystvennoy ptitsy [Morphobiochemical blood tests in poultry]. - 2021: 134 p.

2. Evropeyskaya konventsiya o zashchite pozvonochnykh zhivotnykh, ispolzuemykh dlya eksperimentov ili v inykh nauchnykh tselyakh [European Convention for the Protection of Vertebrate Animals Used for Experimental or Other Scientific Purposes]. - 1986. URL: http://www.conventions.ru/view_base. php?id=19432

3-21. Vide supra.

Author affiliation:

Ovchinnikova Natalya V., graduate student, junior scientific researcher of the Laboratory of Physiology of the All-Russian Research and Technological Institute of Poultry Breeding; 10, Ptitsegradskaya st., Sergiev Posad, Moscow region, 141311; e-mail: natalya.o90@mail.ru.

Responsible for correspondence with the editorial board: Kuzmina Irina V., Ph. D. in Biology, junior scientific researcher of the Laboratory of Physiology of the All-Russian Research and Technological Institute of Poultry Breeding; 10, Ptitsegradskaya st., Sergiev Posad, Moscow region, 141311; e-mail: irina. kislova1606198@yandex.ru.