Differing planes of nutrition alter serum and histotroph amino acid composition in nonpregnant, multiparous beef cows on day 3 of the estrous cycle

Authors: SWANSON, REBECCA - North Dakota State University; NEVILLE, TAMMI - North Dakota State University; MCCARTHY, KACIE - University Of Nebraska; KASSETAS, CIERRAH - North Dakota State University; BOROWICZ, PAWEL - North Dakota State University; Crouse, Matthew; REYNOLDS, LAWRENCE - North Dakota State University; DAHLEN, CARL - North Dakota State University; CATON, JOEL - North Dakota State University

Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/17/2024
Publication Date: 7/19/2024
Citation: Swanson, R.M., Neville, T.L., McCarthy, K.L., Kassetas, C.J., Borowicz, P.P., Crouse, M.S., Reynolds, L.P., Dahlen, C.R., Caton, J.S. 2024. Differing planes of nutrition alter serum and histotroph amino acid composition in nonpregnant, multiparous beef cows on day 3 of the estrous cycle. Journal of Animal Science. 102. Article skae199. https://doi.org/10.1093/jas/skae199.
DOI: https://doi.org/10.1093/jas/skae199

Interpretive Summary: This study sought to determine the effect of differing nutritional planes, maintaining body weight or moderate body weight loss, on concentrations of blood serum and uterine histotroph amino acids and glucose in nonpregnant, multiparous beef cows on d 3 of the estrous cycle. Furthermore, serum non-esterified fatty acids, blood urea nitrogen, performance, body composition, and carcass characteristics were evaluated. Cows were subjected to their diets for 62 days, resulting in decreased body condition, average daily gain, average daily feed intake, G:F, and a greater change in body weight among moderate loss cows. These data demonstrate our model for moderate body weight loss was successful. Moderate body weight loss cows exhibited alterations in serum and histotroph amino acid composition in the uterine horn contralateral to the corpus luteum (CL). Amino acids are important in protein synthesis and bioactive affects. Alterations in histotroph amino acid composition could negatively impact embryonic and fetal growth and development since it serves as a nutrient supply throughout pregnancy and is especially critical during early pregnancy, before the placenta is fully functional. Albeit, in the present study histotroph amino acid alterations were in the uterine horn contralateral to the CL, which would be opposite of the developing conceptus. Nevertheless, because the two uterine horns communicate via the common uterine body, the pre-implantation conceptus should have access to the histotroph from the contralateral uterine horn. In addition, we also hypothesize that the presence of an embryo is necessary for initiating histotroph secretion in the ipsilateral horn. Thus, future studies are needed to fully elucidate effects of nutritional plane on histotroph nutrient composition, and its potential benefit to conceptus development as well as developmental programming.

Technical Abstract: Endometrial-derived uterine histotroph is a critical component of nutrient supply to a growing conceptus throughout gestation; however, the effect of nutritional plane on histotroph nutrient composition remains unknown in multiparous cows. We hypothesized that differing planes of nutrition would alter histotroph and serum nutrient composition in beef cattle. Thus, we evaluated serum and histotroph amino acid and glucose composition, and serum non-esterified fatty acids (NEFA) and blood urea nitrogen (BUN) in cows individually fed to maintain body weight (0 kd/d, n = 9; CON) compared with those losing moderate body weight (-0.7 kg/d, n = 9; NEG). After 49 d of differing nutritional planes, cows were subjected to the 7-d CoSynch + CIDR estrus synchronization protocol and then slaughtered on d 62. Blood serum (d 0 and 62) and uterine histotroph [d 62; from uterine horns ipsilateral and contralateral to the corpus luteum (CL)] were collected and analyzed for concentrations of amino acids, glucose, and NEFA. Performance characteristics, body composition via ultrasound (d 0 and 62), and carcass characteristics were collected. Body condition score, change in body weight, average daily gain (ADG), dry matter intake (DMI), and gain:feed (G:F) were decreased (P