Effect of increasing concentrations of deoxynivalenol (DON) in diet on health and performance of laying hens of different genetic background

A 12-laying months experiment with laying hens of two different genetic backgrounds was conducted to evaluate the effect of feeding of DON contaminated wheat on performance, egg components and health of the hens and the effect of the breed of the laying hens on the sensitivity towards DON. A total of 216, 23 weeks old laying hens (108 Lohmann Brown, LB, and Lohmann Selected Leghorn, LSL, respectively) were assigned to the feeding trial with increasing concentrations of DON (0, 3.4, 9.9 mg/kg) resulting in 6 experimental groups of 36 hens each. All birds were caged individually and had free access to feed and water. Eggs were collected three times during the experience for the evaluation of egg quality. At the end of the experiment 20 laying hens per group were slaughtered. Blood was collected for haematology. Liver, spleen, heart, breast muscle, glandular stomach and gizzard were dissected, emptied (glandular stomach and gizzard), and weighed. Tissues for histological examination were collected directly after slaughtering. Significant adverse effect of DON was noticed on the laying intensity, body weight and weight gain of the laying hens; laying intensity was significantly decreased due to the presence of DON in the diet in the second laying period while laying intensity of the LSL hens was significantly higher than the LB hens. Moreover, a decrease in life body weight and lower weight gain ratio was detected in the LB hens fed 9.9 mg/kg DON, while the LSL hens were not significantly affected by the dietary treatment. The relative weight of breast muscle of the LB hens fed 9.9 mg/kg DON was significantly lower than that of other LB groups, while the relative weight of liver was significantly higher. on the other hand, breast muscle and liver relative weights of the LSL hens were not significantly affected by the dietary treatment. Haematocrit and concentrations of white blood cells were not significantly affected by the dietary treatment while significant breed differences were observed. Moreover, DON contaminated wheat resulted in reduction in the eggshell proportion of the eggs of the LB hens fed 9.9 mg DON/kg diet at the 40 th and 60 th week of life while LSL eggs were not significantly affected. Overall, it can be concluded that the performance and health of the laying hens was adversely affected by the presence of DON in hen’s diet at the highest level (9.9 mg/kg) but to a different extent and depending on the breed of the laying hens.