Systemic inflammation (SI) is increasingly studied in several species because it may be central in many metabolic disturbances and be a risk factor for clinical disease. This proof-of-concept study evaluated the effects of the anti-inflammatory drug meloxicam on markers of SI and energy metabolism, polymorphonuclear neutrophil (PMN) function, and endometritis in clinically healthy postpartum dairy cows. Cows received meloxicam (0.5 mg/kg of body weight; n = 20) once daily for 4 days (10-13 days postpartum) or were untreated (n = 22). Blood samples were collected −7,

This study evaluated the effects of treatment with meloxicam (a non-steroidal anti-inflammatory drug), parity, and blood progesterone concentration on the dynamics of the uterine microbiota of 16 clinically healthy postpartum dairy cows. Seven primiparous and 9 multiparous postpartum Holstein cows either received meloxicam (0.5 mg/kg SC, n = 7 cows) once daily for 4 days (10 to 13 days in milk (DIM)) or were untreated (n = 9 cows). Endometrial cytology samples were collected by cytobrush at 10, 21, and 35 DIM, from which the microbiota analysis was conducted using 16S rRNA gene sequence analysis. A radioimmunoassay was used to measure progesterone concentration in blood serum samples at 35 DIM and cows were classified as ˃ 1 ng/mL (n = 10) or ≤ 1 ng/mL (n = 6). Alpha diversity for bacterial genera (Chao1, Shannon-Weiner, and Camargo’s evenness indices) were not affected by DIM, meloxicam treatment, parity, or progesterone category. For beta diversity (genera level), principal coordinate analysis (Bray-Curtis) showed differences in microbiota between parity groups. At the phylum level, the relative abundance of Actinobacteria was greater in primiparous than multiparous cows. At the genus level, there was lesser relative abundance of Bifidobacterium, Lactobacillus, Neisseriaceae, Paracoccus, Staphylococcus, and Streptococcus and greater relative abundance of Bacillus and Fusobacterium in primiparous than multiparous cows. Bray-Curtis dissimilarity did not differ by DIM at sampling, meloxicam treatment, or progesterone category at 35 DIM. In conclusion, uterine bacterial composition was not different at 10, 21, or 35 DIM, and meloxicam treatment or progesterone category did not affect the uterine microbiota in clinically healthy postpartum dairy cows. Primiparous cows presented a different composition of uterine bacteria than multiparous cows. The differences in microbiota associated with parity might be attributable to changes that occur consequent to the first calving, but this hypothesis should be investigated further.

Paraoxonase-1 (PON1) is an enzyme found in serum and follicular fluid that protects cell membrane and circulating lipids against oxidative damage. The aims of this study were to measure the direct effects of recombinant PON1 (rPON1) on bovine oocyte maturation at the molecular level (gene expression) and to measure the carry-over effects of PON1 on pre-implantation embryo development in vitro. COCs were submitted to IVM with the addition of 0.0, 0.02, 0.04 and 0.08 mg ml(-1) of rPON1, corresponding to an average PON1 arylesterase enzyme activity of 2.2 ± 0.4, 15.5 ± 1.5, 30.2 ± 3.0 and 57.9 ± 5.0 U ml(-1) , respectively. The results indicated that addition of rPON1 during IVM improved embryo development in a dose-dependent manner as D7 embryo development was 22.2%, 29.4%, 32.2% and 37.0% for the treatment groups, respectively (p = 0.02). In conclusion, addition of PON1 enzyme during IVM exerted dose-related positive effects on embryo development rates to blastocysts.

The aim of this study was to compare the J-Synch and conventional protocols associated with estrus detection in beef heifers and to compare pregnancy rate between non-lactating cows displaying estrus or not during the J-Synch protocol. In Experiment 1, heifers were subjected to timed artificial insemination (AI) in a conventional protocol with ECP (n=147) or J-Synch protocol plus eCG (n=149). The AI occurred 12 hours after estrus expression; or 48 (Conventional protocol) and 72 hours (J-Synch protocol) after device removal for animals not displaying estrus. The J-Synch group received 10 µg of GnRH at AI. In Experiment 2, the J-Synch was performed (n=116 cows), but without eCG injection, and estrus was monitored. Pregnancy rate was not different between protocols in Experiment 1 (Conventional: 50.68%; J-Synch: 60.4%). Heifers that displayed estrus had higher pregnancy rate only in the conventional protocol. In Experiment 2, pregnancy rate was not different between cows that displayed estrus or not. Therefore, performing AI earlier according to estrus expression increases pregnancy rate in conventional protocol, however it does not increase pregnancy rate in the J-Synch protocol.Keywords: early artificial insemination; cattle; estrus behavior; GnRH-based protocol. ResumoOs objetivos desse estudo foram comparar o protocolo J-Synch e o protocolo convencional associados com detecção de estro em novilhas de corte e comparar a taxa de prenhez entre vacas não lactantes que demonstraram ou não estro após o protocolo J-Synch. No experimento 1, as novilhas foram submetidas à inseminação artificial (IA) em tempo fixo em um protocolo convencional com ECP (n=147) ou através do protocolo J-Synch com eCG (n=149). A IA ocorreu 24 horas após o estro; ou 48 (Convencional) e 72 horas (J-Synch) após a remoção do dispositivo naqueles animais que não demonstraram estro. O grupo J-Synch recebeu 10 µg de GnRH no momento da IA. No experimento 2, foi aplicado o protocolo J-Synch (n=116 vacas) sem administração de eCG e o estro foi monitorado. No Experimento 1, a taxa de prenhez não foi diferente entre os protocolos (convencional: 50,68%; J-Synch: 60,4%). Novilhas que demonstraram estro tiveram maior taxa de prenhez apenas no protocolo convencional. No Experimento 2, a taxa de prenhez não foi diferente entre as vacas que demonstraram ou não estro. Assim, antecipar o momento da IA de acordo com o estro aumenta a taxa de prenhez no protocolo convencional, contudo não aumenta a taxa de prenhez no protocolo J-Synch.Palavras-chave: antecipação da inseminação artificial; bovinos; comportamento estral; protocolos baseados em GnRH.

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