Effect of extended photoperiod during winter on growth and onset of puberty in Murrah buffalo heifers

Abstract

Aim: To investigate the effect of extended photoperiod on growth rate, hormonal levels, and puberty in Murrah heifers. Materials and Methods: About 14 Murrah buffalo heifers were divided into normal day photoperiod (NDP; n=7) and extended NDP (ENDP; n=7) groups. The ENDP group was exposed to 4 h of extended photoperiod with artificial light (160 lux) after sunset for 3 months during winter. Results: Group, age and group-by-age interaction effects on plasma glucose concentrations were non-significant (p>0.05). A significant effect of age on non-esterified fatty acids (p0.05) while significant (p0.05). Average daily gain and dry matter intake of heifers were nonsignificant between the NDP and ENDP groups but were comparatively higher in ENDP group. By the end of the experiment, 6 out of 7 heifers attained puberty in ENDP group in comparison to 4 out of 7 in NDP group. Conclusion: Extending the photoperiod by artificial light for 4 h during winter season resulted in better growth rate and early onset of puberty in Murrah buffalo heifers.

Keywords

• buffalo
• leptin
• melatonin
• metabolites
• photoperiod
• prolactin
• puberty