WATER-QUALITY .3. THE EFFECT OF WATER NITRATE AND BACTERIA ON BROILERBREEDER PERFORMANCE

Broiler breeder hens received water containing 1.90, 3.55, 5.19, or 10 .38 mg/L nitrate-nitrogen (0, 10, 20, or 40 mg/L added sodium nitrate) and 0 or 100 CFU/mL Escherichia coli (E. coli) during a 40-wk producti on cycle. Hen day egg production (HDP) was not affected by treatment w ith nitrate or bacteria alone. Combined E. coli and 10.38 mg/L nitrate -nitrogen treatment resulted in egg production significantly (P less t han or equal to .05) lower that that in hens drinking only E. coli con taminated water. Dietary water treatment did not affect follicle size, but fewer (P less than or equal to .05) rapidly growing small follicl es (greater than or equal to 10 mm) and more (P less than or equal to .05) atretic follicles occurred on the ovary of hens as reproductive a ge increased from 15 to 40 wk of egg production. Neither water treatme nt affected fertility of eggs; however, birds consuming 10.38 mg/L nit rate-nitrogen laid eggs with the lowest (P less than or equal to .05) fertile hatchability. Decreased fertile hatchability may results from lowered vitamin A metabolism. Results from this experiment further con firm the negative effect of low-level water nitrate-nitrogen on domest ic poultry.