Effect of feeding rumen-protected lysine through the transition period on postpartum uterine health of dairy cows

Abstract

Feeding rumen-protected methionine as an indispensable amino acid source has been shown to improve reproductive performance in dairy cows, but the effect of feeding rumen-protected lysine (RPL) during the peripartum period on reproductive performance is not well explored. Therefore, we aimed to determine the effects of feeding RPL (AjiPro-L Generation 3, Ajinomoto Heartland Inc.) prepartum, postpartum, or both on follicular dynamics, uterine health, and mRNA gene expression of the endometrium. Seventy-five multiparous Holstein cows were assigned to 1 of 2 dietary treatments with or without RPL in a randomized, complete block design. A 2 × 2 factorial arrangement of treatments was used. Prepartum (-28 d to calving), animals were fed a diet (68% of dietary DM from forage) with RPL [PRE-L; 0.54% RPL of dietary dry matter intake] or without RPL (PRE-C). After calving, half of the cows from each prepartum treatment group were assigned to a diet (56% forage) with RPL (PRE-L POST-L; PRE-C POST-L; 0.40% RPL of dietary dry matter intake) or without RPL (PRE-C POST-C; PRE-L POST-C) until 28 d in milk (DIM). Vaginal discharge was detected with a Metricheck device (Simcro) to detect metritis, and at 28 DIM polymorphonuclear leukocytes were evaluated as a percentage of the epithelial cells using a cytology brush (Andwin Scientific) and an endometrial tissue biopsy was collected for mRNA expression and histology. The first postpartum follicular growth cycle was monitored

Supplementation of rumen‐protected lysine during the close‐up period improves vaginal discharge clearance in Holstein dairy cows

“…In a previous study involving RPL supplementation during the pre‐ and/or post‐partum periods, uterine tissue transcripts linked to inflammation were downregulated 28 days postpartum in cows receiving prepartum RPL supplementation; yet, the PMN percentage was unaffected (Guadagnin et al., 2022). Uterine microbiota similarity was observed between subclinical endometritis and healthy cows at 35 days postpartum; yet, clinical endometritis cows had distinct microbiomes with relatively low bacterial diversity (Pascottini et al., 2020).…”

“…Additionally, Guadagnin et al. (2022) demonstrated that peripartum RPL supplementation did not affect the postpartum follicular dynamics or first ovulation. In that study, the first ovulation occurred 18 days after parturition; most experimental cows ovulated at the time of the earliest ovulation after parturition, and reproductive physiology made it impossible to ovulate earlier.…”

“…Few research studies have explored the impact of RPL supplementation during the close‐up dry period on uterine involution and the resumption of ovarian function in dairy cows. One study demonstrated improved uterine immune function (Guadagnin et al., 2022), yet BUN levels were not examined. Therefore, the effects of RPL supplementation during the close‐up period on uterine involution, ovarian function, and blood parameters, including BUN, in dairy cows fed forage‐ and corn‐based diets were examined in the present study.…”

“…in the RPL group and 15 cows in the CON group ovulated in the first follicular wave, with over 70% of both groups ovulating within the second postpartum follicular wave. Additionally,Guadagnin et al (2022) demonstrated that peripartum RPL supplementation did not affect the postpartum follicular dynamics or first ovulation.In that study, the first ovulation occurred 18 days after parturition; most experimental cows ovulated at the time of the earliest ovulation after parturition, and reproductive physiology made it impossible to ovulate earlier. Therefore, RPL supplementation during the close-up period did not seem to notably affect ovarian function recovery in cows with normal post-calving ovarian dynamics and peripartum nutritional and metabolic status.…”

Environmental and Economic Responses to Precision Feed Management in Dairy Cattle Diets

“…A multiple regression analysis indicated that milk production and milk protein percent were significantly higher when RPM was fed [47]. Amino acids have also been reported to have benefits for reproduction, transition cow health and heat stress [48][49][50][51].…”