A study was conducted to assess the pattern of production of yellow follicle (YF) at the endof the laying period (LP, 23-40 weeks) of broiler breeders (BB) in a tropical commercial farm. Samples were taken fromfour Ross 308 BB flocks of different ages. Ten hens perweek were randomly selected from each flock and individually weighed. Immediately they were hung upside down tied by their feet, killed by neck dislocation and dissected to collect weigh the ovary, oviduct and the egg, if it was present in uterus. Ovarian follicles greater or equal than 0.5g (YF)were separated from the ovary and individually weighed to establish the YF hierarchy, the number of yellow follicles (NYF), the number of follicle pairs (NFP), when two yellow follicles are different by less or equal than 1g of weight, and number positions in the hierarchy (NP=NYF-NFP). Finally, the relationships between NYF, NFP and NP with LP wereassessed. Relationships between egg weight (EW) and ovary weight (OW) and oviduct weight (OvW) were also evaluated. In both cases data was plotted and the regression curves fitted using PROC REG procedures of SAS. Data analysis showed inverse linear relationships between NYF and NP over the laying period, with R-2 values of 0.78and 0.71, respectively. The NYF decreased from 5.9 to 5.0 between weeks 23 and 40 andNpdeclinedfrom 5.8 to 4.9, respectively. The NFP ranged from 0-2 without describing a specific pattern with the PP and 7.6% of the follicles were present as pairs. No clear relationships were found between EW and OW or OvW.
|Number of pages||6|
|Journal||Revista cientifica-Facultad de ciencias veterinarias|
|Publication status||Published - 2011|