English

Abstract

The study was conducted to analyze the laying characteristics of Nera black hens in a hot and humid environment and assess the physical characteristics of good, intermediate and poor layers. Seventy-five eight months old Nera black hens of mean body weight 1.35 ± 0.24 kg (range: 1.20 -1.65 kg) in their 12th week of lay and housed individually in battery cages were used for the study. Eggs were collected daily and recorded for each hen. The hens were subsequently divided into three classes based on their laying performance as follows: Good layers, intermediate layers and poor layers and their physical conditions appraised. Results showed that the peak of lay was between 06:00 to 08:00 h and egg production declined gradually throughout late afternoon hours until no egg was laid between 17:00 and 18:00 h. About 88.75 and 11.25% of the eggs were laid in the morning and afternoon hours, respectively.  Eggs laid between 6:00 and 7:00 h had the heaviest (P<0.05) mean egg weight (70.10 ± 0.92 g) and the first eggs in a clutch were the heaviest eggs (P<0.05). Hens with the longest clutches and shortest number of pause days produced the greatest number of eggs. Good and intermediate layers had smooth, pinkish and full combs and wattles, moist and enlarged vents and flexible pubic bones with wide space in-between. Poor layers had dry combs and wattles, tight and hard abdomen and narrow space between pubic bones. It was concluded that Nera black hens could lay up to 229.68 eggs/annum and lay most eggs between 06:00 and 08:00 h of the day. Egg collection especially in floor managed flocks should be intensified within this time period to minimize losses from cracks and egg eating by the birds.   Key words: clutch traits, egg production, Nera black, oviposition time, pause days.