EFFECT OF SOME GROWTH PROMOTERS ON PERFORMANCE OF WHITE AND BROWN BOVANS LAYERS

Document Type : Research articles.

Authors

Poult. Prod. Dept., Fac. Agric., Fayoum Univ., Egypt

Abstract

A total number of 570 Bovans hens was used in this experiment.
Hens were classified into two equal strains (White and Brown) of 285
hens each and were divided into 3 treatments, each of 95 hens. One
experimental corn- soybean meal diets was formulated. The basal diet
contained 19.0% CP and 2800 Kcal ME/Kg diet was fed during the
laying period. Two types of probiotics were supplemented to the diet (2
kg/ton) to study their effects on productive performance commercial
laying hens compared to the control diet (without growth promoters):1-
Choong Ang Yeast Culture (CYC-100) is a unique live yeast culture
product (saccharomyces cerevisiae 1.510x10
11 CFU/ kg) and 2- More
Yeast (MY) is a unique dead yeast culture (saccharomyces cerevisiae).
Hens in all treatments were kept under a similar management system.
The obtained results were summarized as follows:
It can be concluded that Brown Bovans had significantly better feed
conversion (FC) and economic of efficiency than White Bovans being
5.60 g feed/ g egg mass and 0.747 vs 7.00g feed/ g egg mass and 0.723.
The MY treatment had higher economical efficiency of 0.777 than other
the treatments.
The White Bovans had significantly higher egg production % with lower
egg weight (EW) than the Brown Bovans being 72.81% and 54.66g vs
68.80% and 55.81g, respectively. Hens fed the diets supplemented with
CYC-100 and MY had higher egg production%, EW and egg mass (EM)
than those fed the control diet. The highest egg production%, EW and
EM were shown during the period from 29-32 weeks of age being
90.65%, 60.42 and 4922.05g, respectively.
White Bovans had significantly higher haematocrit value (Ht %) and
haemoglobin value (g/dl) than the Brown Bovans (25.76% and
9.64g/100ml vs 24.30% and 9.05g/100ml, P≤0.05). Hens fed the MY
supplemented diets had lower Ht% and Hb of 24.19% and 8.87g/100ml
than the other treatments.
Diets supplemented with both CYC-100 and MY\ had lower cholesterol
content than those fed the control diet. It can be seen that as birds
advanced in age and production, both Ht% and Hb gradually increased.
The period from 21-24 weeks of age had the lowest Ht, Hb and
cholesterol estimates of 21.55% 8.13g/100ml and 149.05mg/dl
.

Keywords