Effects of the in ovo injection of vitamin D3 and 25-hydroxyvitamin D3 in Ross 708 broilers subsequently challenged with coccidiosis. I. performance, meat yield and intestinal lesion incidence

Authors: FATEMI, S - Mississippi State University; Collins Elliott, Katie; BELLO, A - University Of Alberta; PEEBLES, E - Mississippi State University

Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/6/2021
Publication Date: 8/14/2021
Citation: Fatemi, S.A., Collins Elliott, K.E., Bello, A., Peebles, E.D. 2021. Effects of the in ovo injection of vitamin D3 and 25-hydroxyvitamin D3 in Ross 708 broilers subsequently challenged with coccidiosis. I. performance, meat yield and intestinal lesion incidence. Poultry Science. 100:101382. https://doi.org/10.1016/j.psj.2021.101382.
DOI: https://doi.org/10.1016/j.psj.2021.101382

Interpretive Summary: Previous research had found favorable results for broiler (meat chicken) production when the birds were given a supplemental injection of vitamin D before hatch. A stressor commonly found in commercial broiler houses is coccidiosis. The current study was undertaken to determine if the in ovo (in the egg) injection of vitamin D would be helpful for combatting a coccidiosis infection. Commercial broiler eggs were given a dose of either vitamin D3 or 25OHD3 forms of vitamin D, either separate or combined three days before hatch. Male birds were raised in battery cages (as coccidiosis is transmitted on the ground through birds eating litter) with half of the birds challenged with a coccidiosis vaccine at 14 days of age. A bird from each of the battery cages was sacrificed before the coccidiosis challenge and another after 2 weeks following the challenge in order to rate or score the intestinal lesions following the challenge. The birds in the cages were also weighed and later processed to determine meat yield at 42 days of age. The vitamin D in ovo supplementation, as expected from previous trials, did not impact the hatch of the eggs. The in ovo supplement did not improve the coccidiosis challenge score of the intestines of the birds, however, the 25OHD3 form of vitamin D did increase the body weight of the birds and the breast meat percentage. In conclusion, the 25OHD3 continued to show benefits for the commercial broiler in terms of greater production but did not show any clear benefit on combatting a coccidiosis challenge.

Technical Abstract: Effects of the in ovo administration of vitamin D3 (D3) and 25-hydroxyvitamin D3 (25OHD3) on broiler intestinal lesion incidence, performance and breast meat yield after a coccidiosis challenge were investigated. On each of 10 incubator tray levels, 10 Ross 708 broiler hatching eggs were randomly assigned to each of the following 5 in ovo injection treatments administrated at 18 d of incubation (doi): 1) noninjected; 2) diluent; diluent containing either 3) 2.4 µg D3 (D3), 4) 2.4 µg 25OHD3 (25OHD3), or 5) 2.4 µg D3 + 2.4 µg 25OHD3 (D3+25OHD3). A 50 µL solution volume was injected into each egg using an Inovoject multi-egg injector. Four male chicks were randomly assigned to each of 80 battery cages in each of 2 rooms. Half of the treatment-replicate cages (8) in each room were challenged with a 20× live coccidial vaccine at 14 d of age (doa). One randomly selected bird from each of 4 treatment-replicate cages was scored for coccidiosis lesions before and 2 wk after challenge. Mean BW, BW gain (BWG), feed intake, and feed conversion ratio were determined for all birds from 0 to 14, 15 to 28, and 29 to 41 doa. Carcass weight, and the absolute and relative (% of carcass weight) weights of carcass parts were determined in 3 birds per treatment-replicate cage at 42 doa. Hatchability of live embryonated injected eggs and hatch residue were not affected by treatment. Across challenge treatment, birds in the 25OHD3 treatment group experienced an increase in BWG between 29 and 41 doa when compared to the D3 or diluent-injected birds. Furthermore, pectoralis major muscle percentage tended (P = 0.059) to increase in birds belonging to the 25OHD3 treatment in comparison to birds in the D3 or diluent-injected treatments. These results indicate that regardless of challenge treatment, 2.4 µg of 25OHD3 may increase the BWG and breast meat yield of birds relative to those that only received an injection of commercial diluent.