The impact of ecbolic therapy in the early postpartum period on uterine involution and reproductive health in dairy cows

Efficacy of an herbal formula Guixiong Yimu San in preventing retained placenta and improving reproductive performance in cows

Retained placenta is a common health issue, and appropriate prevention strategies are effective in postpartum health management. This study aimed to evaluate whether early intervention using GYS can prevent retained placenta and puerperal metritis, as well as enhance reproductive outcomes in cows. Each bovine in the GYS group (n = 591) received a single prophylactic dose of GYS (0.5 g/kg body weight) orally within 2 h after parturition, while those in the control group (n = 598) received no intervention. GYS treatment was associated with a decreased incidence of retained placenta (4.6% vs. 12.0%, P < 0.01, OR = 0.335), a lower puerperal metritis risk (8.8% vs. 20.1%, P < 0.01, OR = 0.369), and a reduced need for additional therapeutic antibiotics (11.2% vs. 26.1%, P < 0.01, OR = 0.342). We observed increases in the first service conception rate (59.7% vs. 49.1%, P < 0.01) and conception rate within 305 days postpartum (93.2% vs. 85.5%, P < 0.01) in the GYS group than in the control group. A significant decrease was observed in the number of services per conception (1.8 ± 1.1 vs. 2.1 ± 1.4, P < 0.01) and the calving-to-conception interval (83.6 ± 39.6 vs. 96.6 ± 52.5 days, P < 0.01) between the two groups. Additionally, GYS treatment increased milk yield on days 7, 14, and 28 postpartum without affecting milk fat, milk protein, somatic cell count (SCC), or milk urea nitrogen (MUN) on days 7 and 28 postpartum. Accordingly, the GYS was effective and safe in preventing retained placenta and to improve reproductive performance in cows. Therefore, it could be a prophylactic intervention for superior postpartum fertility in cows.

Novel Approach for Evaluating Pregnancy-Associated Glycoprotein and Inflammation Markers during the Postpartum Period in Holstein Friesian Cows

We evaluated the relationship between decreased pregnancy-associated glycoprotein (PAG) levels, inflammatory parameters (serum amyloid A [SAA] and milk amyloid A [MAA]), postpartum inflammatory conditions (mastitis, ketosis, and follicular cysts), and the FOXP3 gene. Nineteen Holstein-Friesian cows were included in this study. Up to approximately eight weeks after delivery, weekly health examinations were performed for mastitis and ketosis, and reproductive organ ultrasonography was performed. The decreasing PAG rate was negatively correlated with SAA concentration (r = -0.493, p = 0.032). Cows with mastitis exhibited a slower trend of PAG decrease (p = 0.095), and a greater percentage of these cows had MAA concentrations above 12 µg/mL (p = 0.074) compared with those without mastitis. A negative correlation, although nonsignificant (r = -0.263, p = 0.385), was observed between the day-open period and decreased PAG rate. The day-open period was correlated with the presence or absence of follicular cysts (p = 0.046). Four cows that developed follicular cysts were homozygous for the G allele of the FOXP3 gene related to repeat breeders. These results indicate a relationship between a decreased PAG rate and inflammatory status during the postpartum period. Thus, suppressing inflammation during the perinatal period may improve reproductive efficiency in the dairy industry.

Oxytocin, prostaglandin F2α, and scopolamine for uterine involution of dairy cows

The aim of the study was to compare the effect of three substances with ecbolic activity, Oxytocin, Prostaglandin F2α (PGF2α) and Scopolamine, on the uterine involution process in dairy cows and on the resumption of ovarian activity. Eighty bovine were randomly divided in four groups: GROUP C: 20 cows treated, within 24 h of calving, with 5 mL/head of saline solution; GROUP PG: 20 cows treated, within 24 h of calving, with 150 μg/head of d-cloprostenol; GROUP OX: 20 cows treated, within 24 h of calving, with 50 IU/head of oxytocin acetate; GROUP S: 20 cows treated, within 24 h of calving, with 40 mg/q Scopolamine Butylbromide. Each cow was subjected to blood samples to evaluate the Hydroxyproline (HYP) levels, at T0, within 24 h after calving, and T7, T14, T28, 7, 14, and 28 days after calving, respectively. At T14 and T28, an ultrasound examination was performed to measure the diameter of ex-pregnant horn. In all cows, the reproductive indices (days to first service and number of artificial insemination for conception) were evaluated. In all groups, the HYP concentrations have been rising from T0 to T28, with the maximum levels obtained at T28 in the groups PG and S. As regard the diameter of uterine horn, the comparison among the groups showed significant differences only at T28, with lower values in the group PG and S. In group S and PG, the days to first service were less than other groups. Treatment with Scopolamine and PGF2α resulted in better outcomes, evidenced clinically by more efficient uterine involution and faster ovarian recovery.

Understanding microbial networks of farm animals through genomics, metagenomics and other meta-omic approaches for livestock wellness and sustainability

The association of microorganisms with livestock as endosymbionts, opportunists, and pathogens has been a matter of debate for a long time. Several livestock-associated bacterial and other microbial species have been identified and characterized through traditional culture-dependent genomic approaches. However, it is imperative to understand the comprehensive microbial network of domestic animals for their wellness, disease management, and disease transmission control. Since it is strenuous to provide a niche replica to any microorganisms while culturing them, thus a substantial number of microbial communities remain obscure. Metagenomics has laid out a powerful lens for gaining insight into the hidden microbial diversity by allowing the direct sequencing of the DNA isolated from any livestock sample like the gastrointestinal tract, udder, or genital system. Through metatranscriptomics and metabolomics, understanding gene expression profiles of the microorganisms and their molecular phenotype has become unchallenging. With large data sets emerging out of the genomic, metagenomic, and other meta-omics methods, several computational tools have also been developed for curation, assembly, gene prediction, and taxonomic profiling of the microorganisms. This review provides a detailed account of the beneficial and pathogenic organisms that dwell within or on farm animals. Besides, it highlights the role of meta-omics and computational tools in a comprehensive analysis of livestock-associated microorganisms.

Effect of Antimicrobial Treatment on the Dynamics of Ceftiofur Resistance in Enterobacteriaceae from Adult California Dairy Cows

Dairy farm use of antimicrobial drugs (AMD) is a risk for the selection of antimicrobial resistance (AMR); however, these resistance dynamics are not fully understood. A cohort study on two dairy farms enrolled 96 cows with their fecal samples collected three times weekly, for the first 60 days in milk. Enterobacteriaceae were enumerated by spiral plating samples onto MacConkey agar impregnated with 0, 1, 8, 16 and 30 µg/mL ceftiofur. Negative binomial regression analyzed AMR over time. The continuum of ceftiofur concentrations permitted estimation of the minimum inhibitory concentration (MIC) and analysis using interval regression. The most common systemic AMD was ceftiofur, administered in 94% of treatments (15/16 cows). Enterobacteriaceae did not grow in 88% of samples collected from non-AMD treated cows at 8 µg/mL ceftiofur. Samples from AMD treated cows had peak counts of resistant Enterobacteriaceae during AMD treatment and returned to baseline counts by 3-4 days post-treatment at 8 µg/mL. Sensitive Enterobacteriaceae (0-1 µg/mL ceftiofur) were reduced below pre-treated levels for 29-35 days post-AMD treatment. Population MIC peaked during AMD treatment and returned to baseline levels by 7-8 days. We conclude that the effect of systemic ceftiofur on the resistance of Enterobacteriaceae in early lactation dairy cows was limited in duration.

Postpartum Uterine Involution and Embryonic Development Pattern in Chinese Holstein Dairy Cows

Understanding the postpartum uterine involution pattern and embryonic development could facilitate bovine reproduction management, improve reproductive efficiency, and diagnosis of the reproductive disorder, which would contribute to the success of the dairy business. This study aimed to investigate postpartum uterine involution and embryonic developmental patterns or postconceptional marks of embryonic fetal development in Chinese Holstein dairy cows using B-mode ultrasonography. The results revealed a significant decline in the involution period with an increase of parity and age. The uterine involution period was shorter in multiparous cows when compared with cows with lower parities. Consistently, cows over 4 years old recovered faster than younger cows (2 or 3 years). Besides, the elder cows (over 4 years) had a relatively larger size of resumed cervix uteri and horns. Postpartum uterine involution pattern analysis revealed that the reproductive tract recovered very fast during the first 16 days postpartum for all the parity. Results of postconceptional marks of embryo development revealed a slow increase in diameter of the gravid uterine horn and crown-rump length (CRL) before day 60. In contrast, this increase was dramatic and rapid after the 60th day. We also established two models to estimate gestational age based on gravid uterine horn diameter or CRL. A formula was established to determine the gravid uterine horn size during postconceptional on day 30th–day 90th (r = 0.8714, P < 0.01). In addition, a significant positive correlation between CRL and gestational age (r = 0.98151, P < 0.01) was built. In conclusion, these results illustrated that parity and calving age had significant effects on uterine involution in Chinese Holstein cows. Crown-rump length and gravid uterine horn diameter are both efficient for evaluating the embryo growth. These current findings broaden the understanding of basic reproductive pattern in Chinese Holstein cows and could benefit bovine reproductive management primarily in postpartum and early pregnant cows to reduce the calving interval and avoid periparturient metabolic diseases.

Hemodynamic changes evaluated by Doppler ultrasonographic technology in the ovaries and uterus of dairy cattle after the puerperium

The present detailed study aimed to establish for the first time the ovarian and uterine hemodynamic change in dairy cows after the end of the puerperal period to investigate a possible association between Doppler indices and volume of blood flow. Twenty cows weighing 500-600 kg (mean 400 ± 50 kg) and 4-5 years of age (mean 3.2 ± 0.5 years) categorized into two main groups (true anestrum, with corpus luteum, n = 10) and (normal cyclic, n = 10), The period of examination started from day 39 till day 70 after calving with day after day routinely examination by b-mode and Doppler performed on both ovaries with ovarian arteries (OA) and uterus with uterine arteries (MUA) in the ipsilateral (ipsi) and contralateral (contra) side to ovulation, in addition to a thickness in horns and body was measured. Estradiol and progesterone were also measured. Results showed that both Doppler indices in the OA and MUA ipsi and contra had a positive (P ≤ 0.001) correlation with contra Doppler indices, but revealed a negative (P ≤ 0.05) correlation with ipsi and contra Doppler velocities, blood flow rate and volume in anestrum cows. Both ovarian and uterine ipsi indices showed an increase (P ≤ 0.05) in the anestrum cows, and both PSV and EDV of both arteries ipsilateral showed (P ≤ 0.05) a decrease in the anestrum cows, the ipsi and contra ovarian and uterine colored % were lower in anestrum group than the normal group. Estradiol (P ≤ 0.05) decreased in anestrum cows than the normal, while progesterone increased in the anestrum group. Conclusion, although uterine and ovarian morphology were changed in anestrum cows, the vascular system of the ovary as well as uterus underwent much more marked vascular changes, the most significant being that of blood flow velocities and volume.