Effect of feeding different levels of whole wasted egg on feed intake, nutrient digestibility, rumen fermentation parameters and microbial protein synthesis in Kermani male sheep

Considering that the significant numbers of eggs are broken during transport, storage and sale and are not consumable by humans, so it can be used as a high quality feed in livestock diet. Egg is an important alternative feed ingredient that contains high quality crude protein and crude fat. It is estimated that 8% of produced commercial eggs had not a good quality which has good nutritional value for animal consumption. It has been thought that, as a high quality nutrient, unmarketable cracked eggs could be used in animal nutrition and a few studies have been carried out on that respect. Therefore, the purpose of this experiment was to investigate of the effect of feeding different levels of wasted egg as the main source of dietary protein on sheep rumen fermentation, nutrient digestibility and blood parameters.

Whole waste egg were prepared from a commercial laying hen farm during 10 consecutive days. The collected eggs were air-dried away from direct sunlight then grounded. After determining the chemical composition of wasted eggs, levels of 0, 2.5, 5 and 7.5% were used in experimental diets. For determine the effects of wasted egg on sheep, four mature ram (with 44±0.5 live weight) were used in a change-over design with four periods of 21 days. Nutrients digestibility determined by fecal total collection method. In the 5 days at the end of each period at 0, 3 and 6 h after morning feeding, rumen fluid was sampled from sheep by esophagus tube and were filtered through three layers of cheesecloth. Blood samples were collected at the end of each period and 3 h after morning feeding in 10-mL. To determine the amount of allantoin and microbial protein synthesis, the daily urine produced during 24 hours was collected.

In the present study, dry matter intake and digestibility in sheep fed experimental diet were not significantly altered. Ruminal pH was not affected by waste egg. But, ammonia nitrogen and total protozoa population (13.54 and 9.94 respectively) in rumen fluid at three hours after morning feeding increased (P<0.05) by adding of waste egg in sheep’s diet. Total purine derivatives and microbial protein synthesis did not change. Blood cholesterol levels in sheep fed wasted egg were significantly higher (58.75 in control diet vs 69 in 7.5 % whole waste egg diet) than other groups (P<0.05).

In conclusion, waste egg has suitable nutrients for using livestock feed. Whereas, feeding 7.5% of wasted egg increased of total protozoa population and ammonia nitrogen, and improved fermentation condition. Because alter in ruminal fermentation characteristics, this waste can be used as part of a concentrate in the diet of sheep.