Effect of different levels of lysophospholipid on performance, degradability, ruminal parameters, microbial population, and carcass fatty acids in fattening lambs

 Lysophospholipids play an important role in animal nutrition. These substances, which are also classified as plant secondary metabolites, have a positive effect on the digestion and absorption of lipid nutrients in livestock. Lysophospholipids, mostly due to their emulsifying properties, increase the digestibility of fats and fat-soluble vitamins and can selectively prevent the growth of gram-positive bacteria. They can also emulsify dietary fats and increase fat absorption in the intestinal epithelium. The lysophospholipids can improve the consumption of fatty acid supplements and increase their digestibility. Therefore, they have substantial benefits for ruminants. The current study was conducted to evaluate the effects of consumption of different levels of lysophospholipids on degradability parameters, ruminal parameters, carcass fatty acid profile, microbial population, and protozoa in fattening male lambs.

 In this study, 24 crossbred male lambs with four treatments and six replications per treatment were used in a completely randomized design. The experimental diets included: 1. Basal diet (control) (without lysophospholipid in the diet and with a diet containing a lipid source), 2. Treatment containing a lipid source + 0.25% lysophospholipid in the diet, 3. Treatment containing a lipid source + 0.50% lysophospholipid in the diet, and 4. Treatment containing a lipid source + 0.75% lysophospholipid in the diet. The lipid source and lysophospholipid supplement were rumen-protected products. The total fattening period was 105 days (15 days of adaptation + 90 days of recording period).

 The results showed that adding 0.75% of lysophospholipid supplement increased feed consumption and daily weight gain and decreased FCR (P<0.05). With the addition of lysophospholipid supplement to the diet of fattening lambs, there was no significant difference between experimental diets with the control diet regarding the rapidly degraded fraction and slowly degraded fraction and total potential of degradability of dry matter, protein, and NDF (P>0.05). Experimental treatments had no significant effect on pH and ammonia nitrogen. The addition of 0.75% of the lysophospholipid supplement, compared to other treatments, increased the concentration of acetic acid and the ratio of acetate to propionate in the ruminal fluid and also increased linolenic acid (c18:3 ω3) (P <0.05) and the ratio of ω6/ω3 decreased in all experimental groups (P<0.05). The use of 0.5 and 0.75% lysophospholipid supplements in the diet increased the total ruminal bacterial population (P <0.05) but did not affect the population of protozoa (P<0.05).

 Based on the results of this experiment, it is possible to use lysophospholipid supplements at the levels of 0.5 and 0.75% of diets containing fat supplements in fattening male lambs.