Study on the Influence of Various Methods of Induced Molting on Performance and Health of Leghorn Layers

Abstract

The present study was conducted to investigate the impact of various induced molting methods on egg performance and health of leghorn hens which include livability and disease incidences, and economic impact on White leghorn layers. For this purpose, Five Hundred Ten hens were subject into two rearing systems i.e. floor rearing system (FS) and cage rearing system (CS). Each experimental system was randomly divided into five equal treatment groups and each treatment group consisted of three replicates. The first treatment group served as control and was fed on layer diet (CF), while the induced molting was done in other groups according to the following plan. Group B was provided with low energy feed with turmeric (LEFT), C was treated with feed withdrawal (FW), group D with low energy feed with aluminum sulphate (LEFA) and group E with low energy feed (LEF), respectively. After first production cycle (70th week) reared birds were inspected for production performance, egg quality, hematology, intestinal morphology and economics.

Results obtained revealed that during induced molting period maximum body weight loss was recorded in FW treatment, followed by LEFT, LEFA, LEF and CF treatment groups in both systems. Higher body weight was observed in control and lower in feed withdrawal method during post molt stage. Feed intake was significantly higher in LEFT treatment group than control diet. Significantly (P<0.05) higher egg production was recorded in LEFT treatment group than LEF and CF treatments throughout the production period in cage and floor system. Better feed efficiency was noted in LEFT and poor in CF treatment groups. Hen house and hen day egg production was significantly (P<0.05) higher in LEFT and lower in control treatment groups. Higher mortality rate was observed in feed withdrawal and lower in LEFT treatments in cage and floor housing system. Egg weight, shell thickness, shell weight and Haugh unit score were significantly (P<0.05) increased in turmeric treatment. Non-significant difference was observed among the groups for albumin weight, yolk weight, egg length, egg width and egg pH. The dressing percentage and relative weight of visceral and non-visceral organs showed significant (P<0.05) difference among the treatment groups during induced molt period, but difference was non-significant during post molt period. The abdominal fat, spleen weight, length and weight of intestine were significantly affected by treatments during post molting stage. Villus height was higher in control feed treatment during induced molting stage. However, intestinal morphology was significantly improved in LEFT group than other treatments and control feed group during post molting period. The hematological parameters showed significant (P<0.05) difference among the treatment during induced molting except packed cell volume which was non-significant, while during post molting stage non-significant (P>0.05) difference was noted for RBCs, WBCs, and hemoglobin but PCV showed significant difference. The higher RBCs level was recorded in FW and lower in LEF treatment during induced molting stage. Hemoglobin concentration was maximum in FW and minimum in CF treatment during induced molting stage. Furthermore, hemoglobin level was maximum in LEFA treatment and minimum for control feed treatment during post molting period. Minimum packed cell volume was recorded for LEFT treatment and maximum in full feed treatment during induce molting. WHEREAS, data showed that higher PCV was recorded in LEFT and lower for LEFA treatment. T3 and T4 hormone concentration was higher in full feed than other groups. Significantly higher values of T3 hormone was recorded in FW treatment and lower for control feed treatment during molting period. However, maximum T4 hormone level was recorded in FW treatment and lower for CF treatment, respectively at induce molting period. Economics of experimental birds showed that maximum net profit was earned from the LEFT and minimum from control feed treatment. It was concluded from present findings that molting with turmeric method showed better production performance and better economic return than other methods of treatment groups.