EFFECT OF SEMEN DILUTION RATIO AND INSEMINATION INTERVALS ON TURKEY HEN FERTILITY AND EMBRYO VIABILTY

Abstract

The fertility and embryo mortality of indigenous turkeys in response to varied semen dilution ratios for weekly and fortnight inseminations were assessed. In a 2x4 factorial arrangement of a randomized complete block design, 64 local turkey hens were divided into eight groups of eight hens each. Each group of hens comprised four replicates of two hens each. Hens from two replicates were 9 months old while the other two were 16 months old. Semen was pooled from 10 turkey toms. Hens were inseminated with the pooled semen diluted with normal saline at a ratio of 1:0 (T1:0), 1:1 (T1:1), 1:2 (T1:2) and 1:3 (T1:3) containing approximately 90x106, 45x106, 30x106, 22.5x106 motile spermatozoa, respectively, weekly and fortnightly over a period of 12 weeks. Fertility, hatch parameters and embryo mortality were assessed. Data were analysed using ANOVA at α0.05. Fertility at weekly and fortnight inseminations were similar (80.8±1.6% and 81.8±1.6%, respectively), but was significantly (p˂0.05) lower in T1:3 (74.8±2.3%) than T1:0 (87.1±2.2%) and T1:2 (85.3±2.3%) among the dilution ratios. However, with the interaction of the two factors, the only significance observed was in fortnight insemination with T1:3 (72.8±3.1%), which was significantly (p˂0.05) lower than T1:0 (89.3±3.1%) and T1:2 (86.8±3.3%). Hatchability and embryo mortality was similar across all groups. The block effect was not significant across the parameters. Weekly or fortnight insemination intervals with semen diluted at 1:2 or containing approximately 30x106 motile spermatozoa was sufficient to give optimal fertility without compromising embryo viability in the indigenous turkey hens.