PSIII-18 Effect of Industrial Hemp Supplementation on the Salivary Melatonin Concentrations of Angus Cattle at Different Phase of Reproductive Cycle

• Published in: Journal of animal science 2023-11, Vol.101 (Supplement_3), p.394-394
• Main Authors: Samuel, Felix U, Ogunkunle, Nathaniel, Simpson, Monya D, Jones, Kendra, Hering, Josh, Abdelrahim, Gamal-Eden, Verghese, Martha, Cerbet, Ernst, Kuang, Xianyan
• Format: Article
• Language: English
• Subjects: Acclimatization; Animal feed; Antioxidants; Body weight; Cannabaceae; Cattle; Circadian rhythms; Enzyme-linked immunosorbent assay; Estrus; Feed additives; Feeds; Hemp; Immune response; Immune system; Melatonin; Pineal gland; Reproductive cycle; Saliva; Supplements
• ISSN: 0021-8812; 1525-3163
• DOI: 10.1093/jas/skad281.467

Abstract Melatonin is an indoleamine, a neurotransmitter and neurohormone mainly produced in pineal gland but also in the ovary. It has an important role in reproduction, antioxidant, immune system and circadian behavior. Industrial hemp is increasingly being included in animal feeds and it is therefore important to evaluate the effect of industrial hemp supplementation on the profiles of melatonin following different phases of reproductive cycle. Twenty apparently healthy Angus heifers, aged 19 months with average body weight of 363 kg and body condition score of 6.5 were randomly divided into two groups of ten heifers each in a completely randomized design. Group 1 (n = 10) were supplemented with grounded industrial hemp at 20/200mg of the concentrate, and group 2 (n = 10) no industrial hemp supplementation. Hay and water were provided ad libitum. The animals were acclimatized for 1 week after which they were synchronized using the 7-day CO-Synch protocols. Salivary samples were collected at preestrus, during estrus and at post estrus. Melatonin in the saliva was assayed with a competitive ELISA kit. The salivary melatonin concentrations were greater (P > 0.05 in the treated groups at estrus (25.29 ± 1.48 pg/mL), pro-estrus (23.98 ± 2.3 pg/mL) and post-estrus (20.31 ± 3.0 pg/mL) compared with the untreated groups at pre-estrus (18.9 ± 1.5 pg/mL), estrus (20.4 ± 2.22 pg/mL) and post estrus (17.22 ± 2.6 pg/mL).The profiles of the salivary melatonin were greater (P > 0.05) at estrus phase in the hemp treated groups compared with the pre-estrus and post estrus phase of the treated groups; however, numerical but non-significant increases were observed in the untreated group at estrus phase compared with the pre-estrus and post estrus phases. It was concluded that industrial hemp supplementation could improve melatonin concentrations and hence improve reproductive, antioxidant and immune function of the cattle.