Oxidative Stress and Role of Natural Plant Derived Antioxidants in Animal Reproduction

The experimental knowledge on the role of oxidative stress,and beneficial and detrimental effects of plant derived antioxidants in male and female animal reproduction are reviewed in this article.Free radical-induced oxidative stress in animal reproduction causes great loss to livestock industry.Antioxidant therapy has been implicated to be effective in preventing diseases resulted from oxidative stress.Considering the advantages of lower side effects of natural antioxidants than those of synthetic antioxidants,plants or their extracts have been extensively utilized in animals.Although many advances have been gained on application of plant derived antioxidants in alleviating oxidative stress,debatable issues still exist.Because many opposite effects were observed even using plant extracts containing similar bioactive substances in the same animal species.Therefore,plant derived antioxidants,like free radicals,are ＂double-edged swords＂ in animal reproduction,representing that they may exhibit beneficial or detrimental effects in animal reproduction,including spermatogenesis,semen functions,estrous cycles,ovulation,ovary functions,endometrium,embryo development,and pregnancy.Besides dose-dependent manner as an explanation of plant extracts＇ dual function,future studies are needed to investigate the mechanism of double-edged actions of plant derived antioxidants in different animal reproduction systems.

Meat Quality Parameters and the Effects of Stress: A Review

The objective of this review was to address the stress effects on meat quality considering the main attributes that involve meat quality.Animal protein production has been increasing with global demand for meat with meat quality a major concern,especially for more demanding consumers who are looking for quality products to meet their needs.The quality of the meat is the result of what happened to the animal throughout the production chain,that is,good rearing conditions result in a better meat quality.Different types of stress can be harmful to animals due to inadequate or improper animal handling on farms,inadequate transport conditions,poorly maintained trucks and roads,and conditions that agitate animals can lead to bruising,thermal stress.The stress in animals occurs when they are in adverse conditions and can significantly compromise meat quality loss.As an example,stress can significantly affect meat quality parameters as drip loss(DL),meat color,change ultimate pH and cause meat anomalies.Among the main parameters of evaluation used for meat quality are color,characterized by luminosity(L^*,a^*,b^*),lipid and protein oxidation,pH,water holding capacity(WHC)and softness.Producing and processing high-quality meat is a challenge since it is necessary to apply methods that promote comfort in a complete sense,in a way that minimizes inducing significant stress.Based on the results presented it is remarkable that stress alters the meat quality,compromising the main attributes that involve it,like color,pH,WHC,Warner-Bratzler shear force(WBSF),lipid oxidation,among others andis necessary to avoid or reduce stress caused during the production of the animals to ensure a high-quality meat,resulting in greater profitability for the producer.