BACK TO QUEBEC CITY 2002 TITLES
Sexual behaviour and fertility
of broiler breeder flocks illuminated by high-pressure sodium, compact
fluorescent and
incandescent lighting
C.M. Vandenberg and T.M.
Widowski
University of Guelph,
Guelph, Canada
Gas discharge lamps, such as compact fluorescent (CF) and high-pressure sodium (HPS) offer advantages to poultry producers because of energy savings and longer lamp lives. However, the spectral characteristics of these light sources are considerably different from those of standard incandescent (IN) lamps, which may influence bird behaviour and performance. This is especially important for broiler breeder flocks, which depend on visual cues to facilitate natural mating to produce fertile eggs.
In order to determine if light sources affect sexual behaviour and fertility, we observed courtship and mating behaviours and measured fertility from 12 pens of birds (4 pens per light treatment) illuminated by either HPS (84 lux), CF (38 lux) or IN (38 lux). Each pen held 39 Ross broiler breeder hens and 3 Ross broiler breeder roosters from 23 to 65 weeks of age. Live observations were made during weeks 30, 33, 36, 44, 47, 50, 57, 59, and 63 weeks of age with three observation weeks averaged for one period for a total of three time periods. Each pen was randomly observed for 10 minutes/day for two days during the observation week. All observations occurred between 4:30 and 6:30 pm with all-occurrence scan sampling recording the incidence of the following behaviours: waltzing, rear approach, tidbitting and mounting (performed by the rooster) crouching and escaping (performed by the hen) and successful copulations. There were no differences in light treatment for all behaviours (P>0.05) or successful copulations (P>0.33). However, there was a significant decrease in frequencies of sexual behaviour across periods (P<0.05) except for waltzing (P>0.37).
Fertility was tested by collecting nest eggs from each pen for four days on 30 & 36, 44 & 50, and 57 & 63 weeks of age grouped into two weeks per period. There were no differences in light treatment for the mean fertility (P>0.20) and change of fertility between weeks within periods (P>0.84). Again, there was a significant decrease across periods in the mean fertility (P<0.02).
Overall, courtship and mating behaviour decreased with age showing a corresponding decrease in fertility. However, there were no differences between light treatments for either behaviour or fertility.