Effect of using different levels of pistachio seed coat on feed intake, nitrogen retention, microbial protein synthesis and ruminal parameters in Kermani sheep

In order to investigate the effect of using different levels of pistachio seed coat (PSC) on feed intake, ruminal parameters, microbial protein synthesis and nitrogen retention in Kermani sheep, four male sheep with a mean weight of 54 ± 2 kg were used. This experiment was conducted in 4×4 Latin square design in four periods of 21 days. After determining the chemical composition of PSC, it was used in the preparation of experimental diets and replaced with wheat bran. The experimental diets were: 1) control diet (without PSC), 2) diet containing 5 % PSC, 3) diet containing 10 % PSC and 4) diet containing 15 % PSC. The results showed that feed and nitrogen intake, excreted nitrogen and nitrogen retention were not affected by feeding the experimental diets. Adding PSC to the diet, ruminal ammonia nitrogen was reduced (P<0.05), however, it did not affect the pH of ruminal fluid at 0, 2, 4, 6 and 8 hours after feeding (P<0.05). The total protozoa population of the rumen was not affected by experimental diets, while the population of cellulolytic species increased linearly (P<0.05). Among sheep, no significant difference was observed in terms of total purine derivatives, allantoin, creatinine, uric acid, hypoxanthine and xanthine and, of course, microbial protein synthesis. According to the results, and no difference in the factors between the control group and other experimental groups, it can be said that PSC can be used up to 15% of dry matter in sheep diet and can be replaced with wheat bran or other diet ingredients.