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D B Olumeyan

Publications and source records attributed to D B Olumeyan.

2 recordsLinked to original sources

Effect of age and sex of egg strain chickens and of two stocking densities of broilers on voluntary water intake and performance in a sub-humid environment.

Voluntary water intake and performance of egg-strain chickens of different age groups and sex were compared. Cockerels grew faster and consumed 41% more feed and 43% more water than pullets of the same strain and age. Cockerels of nineteen weeks consumed significantly more feed (P < 0.05) than layers of 30 weeks of the same strain, but there was no significant difference in their daily voluntary water intake. The physiological activities associated with egg laying in chickens, apparently require more water to feed ratio than for the active growth of cockerels. In a second experiment, the effect of 2 stocking densities on voluntary water intake and performance were compared. Birds on higher stocking density (0.09 m2/bird) performed similarly to those on low stocking density (0.18 m2/bird), but the higher stocking density birds recorded slightly higher mortality. Voluntary water consumption was not significantly affected (P > 0.05), although birds on higher stocking density recorded slightly higher average daily voluntary water consumption. The higher stocking density birds recorded slightly higher per cent mortality during the 8 week period, but higher per cent mortality was recorded with the low stocking density birds during the 0 to 4 week brooding period.

Aging↗

Rumen microbial changes in cattle fed diets with or without salinomycin.

Four rumen-fistulated steers, randomly assigned to two groups (control and salinomycin fed) were used to monitor the changes in rumen microbial populations and volatile fatty acids (VFA) concentrations associated with feeding salinomycin (0.22 mg X kg-1 X day-1). Steers were adapted to an alfalfa hay and grain (80:20) diet before supplementing the diet with salinomycin, and then the diet was changed to 50:50 and 20:80 ratios of alfalfa hay to grain at 2-week intervals. Rumen samples for total and selective enumeration of anaerobic bacteria. VFA analysis, and enumeration of protozoa were collected during the 80:20 alfalfa hay-to-grain diet before salinomycin feeding, and during the 80:20, 50:50, and 20:80 hay-to-grain diets with salinomycin. At each sampling period, rumen samples were collected at 3 h after feeding on three consecutive days. Salinomycin feeding had no effect on rumen pH and total VFA concentration. The acetate-to-propionate ratio was significantly lower in salinomycin-fed steers than in the control. The molar proportion of butyrate increased in both control and salinomycin-fed steers. Total anaerobic bacterial counts were lower in salinomycin-fed steers than in the control steers after 8 weeks of salinomycin feeding. Salinomycin-resistant bacteria increased from 7.6 to 15.6% in salinomycin-fed steers but remained unchanged in control steers. Salinomycin had no effect on cellulolytic and lactate-utilizing bacteria, but the proportion of amylolytic bacteria was higher in salinomycin-fed steers than in control steers. The total number of protozoa decreased initially in salinomycin-fed steers. The initial reduction was due to reduced numbers of Entodinium species. Holotrichs were unaffected by salinomycin feeding.

Animal Feed↗