Hormones & Cattle Farming
Announcer: Farm and Family is a production of the Mississippi State University Extension Service.
Amy Myers: Today we're talking about hormones and cattle farming. Hello. I'm Amy Myers and welcome to Farm and Family. Today we're speaking with Dr. Erdogan Memili, Professor at Mississippi State University, Department of Animal and Dairy Sciences. Also, with Riley Messman and Lacey Dissert, graduate students majoring in agriculture with a concentration in Animal Science.
Dr. Memili, tell us about your research and teaching philosophies?
Dr. Memili: We study functional genomics of economically important traits with a focus on reproduction in farm animals. The goal of our research is it identify molecular biomarkers and mechanisms to improve reproduction and production of livestock. I am privileged to teach our students the goat and sheep production with laboratory, scientific writing and endocrine secretions.
Amy Myers: Now Riley, tell me about the endocrine secretions class?
Riley Messman: In this class, we studied the endocrine glands, the hormones they secrete and their functions and regulations in the mammalian systems. Working individually or as groups, we also did a class project on hormones in cattle agriculture, welfare and human health. In this project, we first did a comprehensive literature search and found the most relevant articles that were published in peer reviewed scientific journals. Then we critically read a panel of selected articles as a class, discussed them and developed a scientific report.
Amy Myers: Lacey, tell me about the hormones in cattle farming.
Lacey Dissert: Hormones are secreted from the endocrine gland such as the hypothalamus, pituitary glands, ovaries, testes and the uterus to carry out specific functions in cells and tissues. The main endocrine gland, the hypothalamus secretes several hormones including growth hormone, releasing hormone, gonadotropin releasing hormone, corticotropin releasing hormone and thyroid releasing hormone, that target the pituitary gland.
Growth hormone releasing hormone stimulates the pituitary to secrete growth hormone which in turn stimulates the growth of bone, muscle, and will also increase milk production. GNRH also known as gonadotropin releasing hormone stimulates the production of gonadotrope hormones that are follicle stimulating hormone and luteinizing hormone for oocyte or sperm production in maturation in the ovary or testes.
Corticotropin releasing hormone stimulates the pituitary gland to secrete adrenal corticotropic hormone which targets the adrenal cortex to produce the steroid cortisol. Cortisol is a key stress indicator in animals. Furthermore, the corpus luteum or CL forming after ovulation produces progesterone, the pregnancy hormone which allows endometrium to facilitate the developing uterus. So hormones are vital for cattle physiology development, health and welfare.
Amy Myers: So going back to Riley, what are the applications of hormones in cattle farming?
Riley Messman: Hormones can be used to increase the quantity and quality of animal products without negatively impacting animal or consumer health. For example, exogenous growth hormone such as recombinant bovine somatotrophin and growth implants which are compromised of androgens, estradiol, progesterones or synthetic forms of these, can be used to increase carcass traits leading to a higher amount of quality meat selection, such as steaks in your grocery store.
It also improves milk production leading to a greater supply of our cheese, ice cream and milk. Producers can use hormones to improve reproductive efficiency in their cattle as well. They can use estrosynchronization programs to breed their cows earlier in late breeding season, ultimately leading to heavier weaned calves and greater profit.
The usage of hormones allows reproducers to keep up with the increasing food demand, due to an exponentially growing population while reducing the environmental impacts and increasing animal welfare.
Amy Myers: And Lacey, how about the meat and milk from cattle and the take home message from hormones and cattle farming?
Lacey Dissert: In the United States, we are very fortunate to have numerous federal and state laws that regulate food safety. Milk made for human consumption is free of exogenous hormones and antibiotics. Prior to obtaining FDA approval, pharmaceuticals undergo rigorous testing to discover what an adequate withdrawal period will be. A withdrawal period is the period of time needed for animals to metabolize and fully excrete the pharmaceutical that was administered, like hormones.
In the agriculture industry, producers are aware of the withdrawal period for pharmaceuticals and the legislation surrounding it. Withdrawal periods are clearly stated on all hormone and antibiotic labels. It is important to understand that hormones are administered to improve efficiency, animal welfare and the end product, which is quality beef and milk products.
Research has shown that beef or milk from cattle that have received exogenous hormones, do not cause a risk to the animal or to the consumers consuming it. RSBST increases milk production, growth, development and overall efficiency of cattle. Although the FDA has deemed RSBST as safe, the consumer has a negative connotation of this hormone.
There is an opportunity to enhance public understanding of science based solutions for food animal production and product quality.
Amy Myers: Today we have been speaking with Dr. Erdogan Memili, Professor. Also with Riley Messman and Lacey Dissert, graduate students. I'm Amy Myers and this has been Farm and Family. Have a great day.
Announcer: Farm and Family is a production of the Mississippi State University Extension Service.