Ovarian follicular growth and maturation in the domestic pigeon and guinea fowl (Numida meleagris).

Yolks of pigeon and guinea fowl eggs were examined for the number of dichromate-staining rings. Estimates of the time for rapid follicular development using this technique were 5.1 and 5.6 days for pigeons and guinea fowl, respectively. Another measure of follicular development based on the incorporation of Sudan dyes into the yolk yielded an estimate of 6.5 and 8.3 days for pigeons and guinea fowl, respectively. Using one and two-egg clutches, no differences due to clutch position were observed in either species. There was a significant difference (P less than or equal to .01) between results obtained with the two techniques for measuring the period of rapid yolk deposition. The dichromate technique can give valuable data relative to yolk deposition, especially in species where it is impractical to daily catch and administer Sudan dyes. But the tendency to underestimate the period of follicular growth means that caution must be exercised in comparing results obtained with that technique and the more labor-intensive Sudan dye incorporation method. The time from the end of yolk deposition until oviposition is defined as the rest period. This interval was 1.5 days for pigeons and 1.7 days for guinea fowl. This is considerably longer than the rest period of Coturnix quail but similar to that found in turkeys and chickens.