FUNMI ADEBIYI, ANTHONY OLOGHOBO, OLUFEMI ADEBIYI
University of Ibadan, Department of Animal Sciences, Nigeria
This experiment was conducted to investigate the dietary effect of raw garlic on the performance, cholesterol content of egg yolk and serum lipids of laying hens. A total of sixty 18 weeks old Isa Brown layers were randomly assigned to six diets containing raw garlic (0, 1, 2, 3, 4 and 5%) in five replicates of two birds each. The experimental period lasted 20 weeks. Feed intake was assesed weekly. Egg production and egg weight were measured daily. Blood samples were collected from all the birds at week 5, 10, 15 and 20 of the experiment. The serum samples collected were analysed enzymatically for total cholesterol, triglyceride and high density lipoprotein cholesterol. Samples of egg yolks were analysed for cholesterol at the 5th, 10th, 15th and 20th weeks of the experiment. There were no differences (p > 0.05) in feed efficiency, average egg weight and egg mass. High inclusion of raw garlic (4%) significantly (p < 0.05) reduced feed intake by 6.5%. There was a significant (p < 0.05) increase of 15.7% in production per hen and day at 2% inclusion of raw garlic. There was a significant (p < 0.05) reduction in serum total cholesterol, triglycerides, low density lipoprotein and egg yolk cholesterol by 36.6%, 18.1%, 70.6%, and 27.1% respectively. The values of high density lipoprotein cholesterol concentration increased (p < 0.05) linearly in response to increasing levels of dietary garlic (r2=0.80). This study demonstrated that inclusion of raw garlic up to 4% in layers diet could increase hen-day production and decrease egg yolk cholesterol concentration (mgg-1 yolk) and serum lipids without adverse effects on performance of laying hens.
Keywords: Cholesterol, garlic, laying hens, lipid metabolism