Trans-Generational Effect of Feeding Genetically Modified maroACC Corn to Laying Hens and Offspring Roosters on Offspring Roosters Growth and Reproduction

ABSTRACT: The aim of this study was to evaluate the chronic effect of feeding a transgenic corn line containing maroACC gene from the Agrobacterium tumefaciens strain (CC) to laying hens and their offspring roosters on growth and reproduction of offspring roosters. Healthy White Leghorn laying hens (n = 72 placed in cages; 3 hens/cage) were randomly allotted to 3 corn-soybean meal dietary treatments (8 cages/treatment) formulated with non-transgenic near-isoline control corn (CT), CC corn, or commercially available non-transgenic reference corn (RF). After 12 weeks, fertile eggs were collected and hatched for 21 days. A total 108 offspring cockerels were assigned to 3 dietary treatments for 32 weeks: i) CT corn-fed parental hens/CT corn-fed offspring cockerels (CT / CT); ii) CC corn-fed parental hens/CC corn-fed offspring cockerels (CC / CC); iii) RF corn-fed parental hens/RF corn-fed offspring cockerels (RF / RF). Each dietary treatment had 36 offspring cockerels and was assigned to 6 replicates with 6 offspring cockerels per replicate. Body weight and feed intake were determined weekly. The semen quality was measured at the end of 28 and 30 weeks. At the end of 32 weeks, offspring roosters were harvested and the carcass yield were recorded (n=6/treatment). Secondary sex characteristics (the size and weight of rooster cockscomb and whisker) of offspring roosters were measured at the same time. Testes were weighed and sampled for histological analysis. Serum was collected for sex hormone analysis. There was no difference in body weight, feed intake and carcass yield between the CT/CT diet and the CC/CC diet. The testis weight, histology and health were not affected by the dietary treatment. No difference was observed in semen quality indicies between roosters consuming the CT/CT diet and roosters consuming the CC/CC diet. The serum concentration of prolactin and estradiol for roosters fed the CC/CC diet were lower (P＜0.05) than those fed the CT/CT diet. The concentration of follicle-stimulating hormone, luteinizing hormone, and testosterone were not affected by dietary treatment. The weight and height of rooster cockscomb and the weight and size of rooster whisker for roosters fed the CC/CC diet were similar with those fed the CT/CT diet, but the length and thickness of cockscomb for roosters fed the CC/CC diet were less (P＜0.01) than those fed the CT/CT diet. In conclusion, trans-generational feeding of maroACC corn has no negative effect on growth and reproductive performance of offspring roosters.