Effects different levels of Lysophospholipid on growth performance, nutrient digestibility, carcass characteristics, some blood parameters and hepatic enzymes in crossbred Zell - Afshari fattening male lambs.

Objective: : In mixed breeds or high-yielding breeds that require the use of lipid resources in the diet to provide the required energy level for livestock, in order to increase fat consumption and increase its digestibility, the use of lysophospholipids has advantages. Also, the possibility of using fat in the diet while maintaining other conditions of gastrointestinal physiology, reduces the consumption of grains and prevents metabolic disorders such as acidosis. This study was performed to investigate the effects of consumption of different levels of lysophospholipids on performance, quantitative and qualitative traits of carcass, apparent digestibility, some blood parameters and liver enzymes in male fattening lambs of Afshari breeds.
Materials and methods: In this study, 24 male lambs of Zell mixed with Afshari with an average weight of 29.85 ± 1.9 kg and an average age of 4 months were used. Experimental lambs were tested in 4 treatments and 6 replications in each treatment for 90 days. Experimental treatments include: 1) control treatment without adding lysophospholipid in the diet and with diets containing lipid source 2) diet treatment containing lipid source plus 0.25% lysophospholipid in the diet 3) diet treatment containing lipid source plus adding 0.5 % lysophospholipid in diet 4) Diet treatment contained lipid source plus addition of 0.75% lysophospholipid in diet.
Results: The results showed that the addition of lysophospholipid supplement to the diet of fattening lambs had a significant effect on daily feed intake (P <0.05). The use of 0.75% lysophospholipid supplement increased feed intake. In the present study, the use of 0.75% of lysophospholipid supplement diet reduced the numerical value of feed conversion ratio, but this reduction was not numerically significant (P <0.05). The final live weight was higher in the lysophospholipid supplementation treatments than in the control group. Also, the group that received 0.75% of lysophospholipid supplement had a higher final weight than the control group and other groups (P <0.05). Dry matter and crude protein digestibility were not significantly different in the experimental groups and the control group. However, the apparent digestibility of crude fat increased in all groups that received lysophospholipid supplementation compared to the control group. NDF digestibility increased in the groups that received 0.5 and 0.75% of lysophospholipid supplement diet. However, ADF digestibility increased significantly only in the group that received 0.75% lysophospholipid supplementation. Experimental treatments had no effect on the serum glucose concentration of crude protein in experimental animals. Also, serum urea, cholesterol, triglyceride, LDL and VLDL concentrations increased with lysophospholipid supplementation. But the serum HDL concentration decreased. Also, experimental treatments had no effect on the concentration of liver enzymes in blood serum. Although the concentrations of alkaline phosphatase (ALP), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were numerically higher on day 90 in the groups receiving lysophospholipid supplementation, but this increase was statistically significant. Was not significant (P <0.05).
Conclusion: Due to the positive effects of lysophospholipid supplement on fat digestibility, functional traits and without creating unfavorable conditions on fiber digestibility (NDF and ADF), liver enzymes can be used in the diet of Afshari mixed breeding male lambs.