PHOTOPERIOD EFFECT ON GROWTH, REPRODUCTIVE TRAITS, HORMONAL AND THERMO-PHYSIOLOGICAL RESPONSE OF THE PEARL GUINEA FOWLS

<p><strong>Background.</strong> Guinea fowl production is gaining much attention and recognition across the globe.  However, the bird’s inability to lay fertile eggs all year round is one of the key challenges to commercialization and intensive production. <strong>Objectives/hypothesis. </strong>This study examines the photoperiod effect on growth, reproductive traits, hormonal and thermo-physiological response of the Pearl Guinea fowls. This study hypothesize that photoperiod will solve the seasonal breeding behaviour among Guinea fowls. <strong>Methodology.</strong> This study was conducted at Dawu in the Ashanti Region of Ghana. Birds used for this investigation were subjected to different photoperiod: 12HL:12HD, 14HL:10HD, 16HL: 8HD and 18HL:6HD using a white bright LED Energy saving bulbs of 120 watts with light intensity of 5.60 lux and kept from day-old to 168 days in a completely randomized design. <strong>Results.</strong> Birds subjected to 18HL:6HD treatment group recorded the highest (P &lt; 0.05) final body weight (1757.23 g/bird), body weight gain (1734.33 g/bird), daily weight gain (10.32 g/bird), total feed intake (6627.3g/bird) and daily feed intake (39.45 g/bird). Birds subjected to 14HL:10HD had the best (3.809) feed conversion ratio. Birds subjected to 18HL:6HD laid earlier (P &lt; 0.05) (130 days) with the lowest (P &lt; 0.05) egg weight of 23.33 g. While birds subjected to 12HL:12HD reached 184 days before starting egg production (P &lt; 0.05) but recorded the highest (P &lt; 0.05) egg weight of 37.33 g. Birds in the 18HL:6HD treatment group recorded the highest (P &lt; 0.05) percentage fertility (86.94) followed by 16HL:8HD (79.86 %) and 14HL:10HD (79.44 %). Hatchability was very high among birds subjected to 16HL:8HD and 18HL:6HD with mean values of 82.89 % and 82.69 % respectively. FSH, LH, Prolactin and testosterone levels in the blood increased with increasing photoperiod (P &lt; 0.05). Birds on the 18HL:6HD treatment had the highest (P &lt; 0.05) body temperature (41.57 ^oC), pulse rate (270.87 Beats/min), respiratory rate (42.69 Breath/min) and rectal temperature (42.95 ^oC). <strong>Implications.</strong> Except for birds subjected to 12HL:12HD, birds across the other photoperiod groups were able to lay fertile eggs across the period of study. <strong>Conclusion. </strong>This study concludes that, photoperiod levels up to 18HL: 6HD promote rapid growth, reduce age at first egg laying, improve fertility and hatchability of Guinea fowl eggs and boost hormonal production.</p>