The effect of hydroxy-selenomethionine on the productive and reproductive performance of old broiler breeders.

Background: Selenium (Se) is a rare essential element that plays a vital role in the health and performance of animals. By interfering in the production of antioxidant enzymes such as glutathione peroxidase, thioredoxin reductase and methionine sulfoxide, Se plays a role in reducing the effects of oxidative stress and animal performance.

Objectives: This study aimed to investigate the effect of hydroxy-selenomethionine (OH-SeMet) in the diet of broiler breeder and old broiler breeder roosters on productive performance, reproduction and sperm quality parameters.

Investigation of enrofloxacin and chloramphenicol residues in broiler chickens carcasses collected from local markets of tabriz, northwestern iran.

Background: The present study was aimed to determine the residual amounts of chloramphenicol and enrofloxacin in broiler chickens muscle and liver sam-ples gathered from local markets of Tabriz City, northwestern Iran.

Methods: Ninety broiler chickens carcasses were collected from different local markets of Tabriz, during July/August 2013. Random samples of thigh and breast muscle and liver were gathered and kept at -80(°)C until analyzes.