Lupine is applicable in diets for layer chickens of parental flock

Abstract

Climatic conditions in most Russian regions are unfavorable for the cultivation of soy beans which are considered the best protein source in diets for all types of poultry. Soya yield in Russian soya-producing regions (Far East, Krasnodar Krai, and some other southern territories) cannot provide the growing poultry production with this important protein source. The alternatives for soybean meal and other soya products are therefore in need; domestically selected low-alkaloid cultivars of white and narrow-leaf lupine are increasingly gaining importance as vegetable protein sources. Feed-grade lupine usually contains up to 42 % of crude protein. The disadvantages of lupine are high contents of fiber (12.5-16.0 %) and lignin (0.9 %), and the presence of alkaloids. Alkaloid content in sweet lupine cultivars is 0.008-0.12 %, in bitter cultivars 1-3 %. Chemical and amino acid composition of white lupine modern cultivars was earlier determined, and their efficiency in poultry diets was studied in vivo. It was found that the grain of low-alkaloid cultivars Gamma, Dega, Dikaf 14 can be included into the diets for poultry at 15-20 % dosage. Supplementation of lupine-containing diets with proper enzyme preparations can improve the digestibility of dietary nutrients and poultry performance. Dehulling of lupine grain decreases fiber content and increases protein content in concentrated lupine-based protein feeds; the latter in dehulled lupine is close to that in soybean products. This original research for the first time proves the possibility of soybean and sunflower meals substitution for white low-alkaloid lupine cultivar Dega the in diets for parental flock of laying hens. The trial was performed on 5 groups of parental White Leghorn layers (cross SP 789) from 184 to 365 days of age fed balanced diets containing 0; 5; 7; 10; and 15 % of dehulled Dega lupine grain (39.61 % crude protein, 5.60 % crude fiber). It was found that 5-10 % lupine does not impair livability and productivity parameters in layers. Lupine was found to influence the intensity of lay, egg fertility, hatch of chicks, micromorphology of liver in hens. The substitution of soy for lupine (7, 10, and 15 %) improved egg production and egg weight output per hen by 1.51 and 7.10 %; 3.31 and 1.64 %; 6.56 and 3.64 %, respectively, in compare to control; feed expenses per 1 kg egg weight in these groups was 0.9; 4.07; and 1.81 % lower. The percentages of infertile eggs and early embryonic deaths in using 10 and 15 % lupine were lower compared to control, evidencing the absence of negative impact of lupine Dega on early embryonic development. The highest doses of lupine did not increase the incidence of late embryonic deaths in eggs from layers aged 47 weeks: the percentages of late embryonic deaths and weak chicks from layers fed 15 % lupine were 4 and 5 % vs. 9 and 8 % in control. The histological investigation of liver revealed no significant differences between lupine-fed and control layers; nucleoplasmic ratio in the hepatocytes was similar in all treatments. In all treatments liver had no abnormalities, the connective tissues were poorly developed and located in the peripheral segments of the liver (where it forms a capsule) and near the portal triad. The hepatic plate structure is well developed, and the tortuous plates are radially oriented. The clusters of blood cells are seen in the lumen of the central veins and sinuous capillaries. Hepatocytes are not clearly bordered, polygonal in shape; nuclei centered or sometimes slightly peripherally shifted, round or oviform, has 1-4 nucleoli. Cytoplasm is unevenly stained, granular; lymphoid cells are found in the stroma and parenchyma. The results of histological investigation of liver, productivity parameters in layers, and the efficiency of incubation of eggs obtained evidence that 5-15 % of Dega lupine dehulled grain as a protein source in diets of laying hens from parental flock does not impair productivity and rendered no cytotoxic effects on the liver of hens. This cultivar of white lupine can be recommended as a dietary protein source both for commercial and parental layer flocks.