Activity of alkaline phosphatase in male lamb blood serum in relation to age and growth rate

Abstract

Purpose: to assess the correlation of serum alkaline phosphatase with the live weight and growth rate of male lambs during the milk and post-milk growing periods.Materials and methods. The study of indicators of serum alkaline phosphatase activity in 74 male lambs aged one and five months was carried out in connection with the intensity of growth and the peculiarities of metabolism. All the male lambs were born at the same time and were raised for up to six months under similar feeding and maintenance conditions. To study the dynamics of changes in the live weight of young animals, individual weighing was carried out monthly with an accuracy of 0.1 kg. Based on the results of weighing, the absolute, relative, and average daily live weight gains were calculated and the animals were divided into three groups. The analysis of the serum for the content of the studied parameters was performed by photometry with the help of the corresponding sets of reagents of the company «VitalDiagnostics SPb».Results. During the observation period, the average increase in live weight of male lambs was 21,14 kg, or 136,75 g per day. At one month of age, the activity of alkaline phosphatase was 188,61±9.50 U/l, and at five months — 100,01±3,58, or 47% (P<0,001) lower. It was found that the activity of the enzyme during the suckling period was positively associated with live weight and growth intensity (r=0,35 and 0,49), and after weaning from mothers — negatively (r = -0,46 and -0,46, respectively). The activity of alkaline phosphatase was consistently increased in monthly male lamb when they moved from a group with lower productivity to a larger one — 160,5 — 191,4 — 214,9, and in five-month-olds, on the contrary, decreased — 121,0 — 98,1 — 80,2 E/l. At the age of one month, the increase in growth intensity was accompanied by an increase in the blood serum of male lamb values of gamma-glutamyltranspeptidase, glucose, calcium and phosphorus, and a decrease in urea and cholesterol levels. At the age of five months, both the list of links and their vector changed. In the serum of fast-growing animals, the de Ritis coefficient and gamma-glutamyltranspeptidase were higher, but the activity of lactate dehydrogenase and creatine phosphokinase was lower.Conclusion. The presence of a correlation between alkaline phosphatase and growth makes it possible to use alkaline phosphatase in zootechnical practice and breeding work as an additional criterion for the growth potential of male lambs up to six months in the early stages of ontogenesis. However, the change in the nature of the relationship from plus to minus implies a differentiated approach in the use of this indicator, taking into account the age of the male lambs.