Effect of semen extenders on viability of ISA Brown and Hubbard Flex roosters' sperm stored for 24 h

Artificial insemination is used in almost 95% of turkey reproductive flocks and is becoming more important in chickens, particularly broiler breeders, as well as in assisted reproduction of wild birds kept in breeding centers. Diluted semen is recommended for artificial insemination. Pooled semen samples collected twice a week by dorso-abdominal massage from 2 chicken lines: laying—ISA Brown (ISA-B) and meat type—Hubbard Flex (H-F) were divided into 5 parts: neat semen and diluted in 1:2 ratio with 4 extenders: basic EK; EK + 1 μg/mL organic selenium and 8 μg/mL vitamin E; EK + 10 mg/mL of royal jelly; and EK + 0.25 g/mL of lyophilized bovine colostrum. Diluted semen samples were evaluated after 15 min and then 24 h storage at 4°C. Sperm concentration, motility, motility parameters (with Sperm Class Analyzer), and morphology were evaluated in the neat semen, whereas in diluted and stored samples, the last 3 traits were determined. In case of both lines, dilution did not affect (P > 0.05) the number of live normal cells (78.0–81.1% in ISA Brown and 73.8–68.7% in Hubbard Flex) in relation to neat semen; however, bovine colostrum addition increased (P < 0.05) the percentage of bulb head sperm (5.7 vs. 10.0% and 12.1 vs. 17.6%, for ISA and Hubbard, respectively) and decreased sperm motility (67.4 vs. 92.9% and 67.3 vs. 98.5% for ISA and Hubbard). The 24 h storage of neat semen and semen diluted with colostrum caused (P < 0.05) the unfavorable changes in all evaluated traits and both chicken lines, whereas semen dilution with remaining extenders decreased the percentage of live normal cells (by 18.8–23.4% ISA and by 20.9–25.5% Hubbard) but did not affect sperm motility (81.5–87.6% for ISA and 81.1–96.6% for Hubbard). Sperm motility and motility parameters depended both on the extender and chicken line.