Postpartum Dairy Cows Research Articles

Effect of Gestational Direct-Fed Microbials Supplementation on the Metabolic Profile in Periparturient Dairy Cows.

This study was conducted at a commercial dairy farm in Queensland, Australia to evaluate the effects of feeding a lactic acid bacteria-based direct-fed microbial (DFM) during gestation on the metabolic profile of periparturient dairy cows and its effects on milk production and body weight. A total of 150 multiparous Holstein cows were randomly selected based on parity (2.3) and days in milk (130 DIM) and divided into two groups of 75 cows each (control and DFM). The control cows were assigned to a basal diet consisting of a silage-based partial mixed ration (PMR), concentrate fed in the dairy twice a day, and ad libitum pasture. The DFM group received the same basal diet supplemented with three strains of Lactobacillus top-dressed in the feed. The DFM supplementation continued during both the dry period and the subsequent lactation. A subset of 82 cows (40 control and 42 DFM) were monitored during the calving season (March to July 2022) to assess the metabolic profile and postpartum performance. Blood samples were collected during the periparturient period (-4 to -2 w prepartum, around calving, and at weeks 1, 3, and 6 postpartum) to measure the levels of metabolites, enzymes, and minerals. Overall, the serum glucose, NEFA, and chloride levels were higher, while protein and urea were lower in cows supplemented with the DFM (p < 0.005). The pre-calving levels of glucose were higher and the total bilirubin, urea, and BHB were lower in cows supplemented with DFM than in the control (p < 0.05). The post-calving levels of glucose and Mg were also higher in the DFM cows than in the control cows (p < 0.05). Average milk production at 110 DIM was significantly higher in the DFM cows compared to control cows (p = 0.03). Although the total milk production over 305 days was numerically greater in the DFM cows, the difference was not statistically significant (p = 0.3), whereas the milk protein percentage was higher in the control cows (p = 0.03). The body weight of the DFM cows was greater during the periparturient period (p = 0.001) than that of the control cows. In the DFM cows, glucose levels had a positive correlation (r = 0.16) with milk yield, at 110 DIM, while serum total protein had a positive correlation with body weight (r = 0.32) (p < 0.05). In conclusion, feeding Lactobacillus-based DFM during gestation can positively influence the metabolic profile of periparturient cows, which, in turn, may affect the milk production and body weight of postpartum dairy cows.

Fertility outcomes in cows with subclinical endometritis after clinical cure of clinical endometritis

Clinical endometritis (CE) is common in post-partum dairy cows and is associated with impaired reproductive performance. The aim of the study was to evaluate the effect of subclinical endometritis (SE) in cows clinically cured of CE on their fertility. The study was performed on 215 Holstein Friesian cows with CE diagnosed by vaginoscopy and ultrasound between 21 and 28 days after parturition. All cows were clinically examined three times at an interval of 2 weeks. Cows without signs of CE were considered cured, and endometrial samples from the uteri were collected by cytobrush to diagnose SE using cytological evaluation of polymorphonuclear neutrophils (PMNs) percentage. The threshold for SE was set at ≥ 5% PMNs. Intervals calving to oestrus and calving to conception, first AI pregnancy rate, pregnancy rate 200 days after artificial insemination (AI), the number of AI per pregnancy (AI/P), pregnancy loss, and culling rate were calculated. SE was diagnosed in 40.9% of cows clinically cured of CE. There were significant differences in the AI/P (3.2 vs. 2.6; p < 0.027) and the pregnancy loss (18.2% vs. 4.7%; p < 0.002) between cows with SE and without SE. Cows with SE showed a tendency towards longer interval calving to conception, lower pregnancy rate 200 days after AI, and higher culling rate. In conclusion, SE after a clinical cure of CE may reduce fertility in dairy cows.

Chromium and Palmitic Acid Supplementation Modulate Adipose Tissue Insulin Sensitivity in Postpartum Dairy Cows

Periparturient dairy cows exhibit intense lipolysis driven by reduced dry matter intake, enhanced energy needs, and the loss of adipose tissue (AT) insulin sensitivity. Extended periods of low insulin sensitivity and negative energy balance induce lipolysis dysregulation, leading to increased disease susceptibility and poor lactation performance. Chromium (Cr) supplementation improves systemic insulin sensitivity, while palmitic acid (PA) increases energy availability for milk production. However, the effect of supplementing Cr and PA alone or in combination on insulin sensitivity in AT is unknown. Thirty-two multiparous cows were used in a randomized complete block design experiment and randomly assigned to one of 4 diets fed from 1 to 24 DIM. Diets included: control, no supplementation (CON, n = 8); Cr (Cr-propionate at 0.45 ppm Cr/kg DM, n = 8); PA (1.5% DM, n = 8); or Cr+PA (n = 8). Plasma samples were collected at -13 ± 5.1 d prepartum (PreP), and 14.4 ± 1.9d (PP1) and 21 ± 1.9d (PP2) after calving for albumin, BHB, BUN, calcium, cholesterol, glucose, nonesterified fatty acids (NEFA), total protein, iron, transferrin, triglycerides, and oxylipids quantification. Subcutaneous AT (SCAT) explants were collected at PreP, PP1 and PP2 and incubated in the presence of the lipolytic agent isoproterenol (ISO = 1 µM, BASAL = 0 µM) for 3 h. The antilipolytic effect of insulin (1µL/L) on SCAT explants was evaluated during ISO stimulation (IN+ISO). Lipolysis was quantified by glycerol release in the media (nmol glycerol/mg AT). Macrophage infiltration and adipocyte size were measured using hematoxylin and eosin-stained AT sections and immunohistochemistry. Cr tended to reduce postpartum NEFA concentrations when compared with CON, PA, and Cr+PA. Likewise, Cr increased the percentage of large adipocytes (>9000 µm2) postpartum compared with other diets. In line with higher lipid content, Cr-fed cows had higher ex-vivo BASAL lipolysis at PP2 when compared with PA and Cr+PA. ISO induced higher lipolysis at PP1 and PP2 but it was not affected by Cr and PA. IN+ISO reduced lipolysis by 29.91 ± 11% in Cr compared with ISO. In contrast, IN+ISO did not affect ISO lipolysis in CON, PA, and Cr+PA. Plasma transferrin was reduced by Cr. At PP2, PA cows had 3.3-fold higher macrophage infiltration in SCAT when compared with CON and Cr. Plasma 9-HODE and 9-oxoODE were increased by Cr+PA. PA increased plasma 13-oxoODE and Cr increased the ratio of 13-HODE:13-oxoODE. PA increased 5-iso Prostaglandin F2α-VI. Our results demonstrate that supplementing Cr during the immediate postpartum enhances SCAT insulin sensitivity and lipid accumulation. Further studies should determine the effects and mechanisms of action of Cr and PA on AT lipogenesis, adipogenesis, and their impact on lactation performance.

183 Comparison of presynchronization and OvSynch protocols following fixed-time breeding in lactating dairy cattle

Abstract Current study was carried out to compare two presynch-OvSynch protocols with standard OvSynch protocol in postpartum Holstein dairy cattle. Postpartum cows (n = 473) were randomly divided into one of the three protocols: I) G7G-OvSynch (n = 159), cows were subjected to PGF2α followed by GnRH 48 h later. After 7 d post-GnRH injection, standard OvSynch protocol was introduced, II) G7GM-OvSynch (n = 162), cows were subjected to the same protocol as in group I) except one extra PGF2α at 12 h interval in Ovsynch part, and III) standard OvSynch protocol (n = 152). The progesterone (P4) profile was subjected to d 30 and d 60 post FTAI. Ovarian status was monitored at the 1st GnRH, PG, and 2nd GnRH injection of the breeding part. Pregnancy/ AI was diagnosed on d 30,60, and 90 post-FTAI, and pregnancy loss was also on d 60 and 90 post-FTAI. Pregnancy data were analyzed using the Chi-square test and plasma P4 profile by ANOVA using SAS. Ovulatory follicle diameter (mean ± SD) was 15.44 ± 1.24 in G7G-Ovsynch, 15.21 ± 1.36 in G7GM-OvSynch, and 14.90 ± 1.02 in OvSynch, respectively (P &amp;gt; 0.05). Plasma P4 profile (ng/mL; Mean ± SD) on d 30 post TAI was 6.50 ± 1.39,7.01 ± 1.13 and in 6.49 ± 1.32 G7G-OvSynch, G7GM-Ovsynch and OvSynch groups, respectively (P = 0.09). On d 60 post TAI, P4 profile was recorded to be 7.75 ± 1.20, 7.58 ± 1.36 and 6.80 ± 0.96 in G7G-OvSynch, G7GM-OvSynch and OvSynch, respectively (P &amp;lt; 0.05). P/AI on d 30 was 51.57% (83/159), 57.41% (93/162) and 42.76% (65/152) G7G-Ovsynch, G7GM-OvSynch, and OvSynch, respectively (P = 0.033). Similarly, AI on d 60 and d 90 post FTAI was 44.65% (1/159):51.85% (84/162), 38.16% (58/152): 43.40% (69/159) and 51.23% (83/162):36.18% (55/152) in G7G-Ovsynch, G7GM-OvSynch, and OvSynch protocols (P = 0.051: 0.027), respectively. Pregnancy loss on d 60 and d 90 post FTAI was 13.41%: 2.90%, 9.68%: 1.20% and 10.77%: 5.20% in G7G-Ovsynch, G7GM-OvSynch, and OvSynch, respectively (P = 0.73: 0.35). Although statistically non-significant (P = 0.56), overall pregnancy loss on d 90 post-FTAI was also numerically greater in the G7G-OvSynch (15.85%) protocol as compared with G7GM-OvSynch (10.75%) and OvSynch (15.38%). We concluded that the G7GM-OvSynch protocol has resulted in an increased P/AI, P4 profile in comparison with G7G-OvSynch and OvSynch. Similarly, pregnancy loss was also less in the G7GM-Ovsynch protocol, which makes it a protocol of choice for postpartum dairy cows.

Adipose Tissue Oxylipin Profile Changes with Subclinical Ketosis and Depot in Postpartum Dairy Cows

Lipolysis of adipose tissue is a natural occurrence during the periparturient period in dairy cows. However, when lipolysis rates exceed the capacity of other tissues to utilize nonesterified fatty acids (NEFA), it may lead to the development of ketosis and other diseases. Additionally, polyunsaturated NEFA (PUFA) can become oxidized into oxylipins, which modulate inflammation and metabolism. The objective of this work was to identify depot-specific differences on adipose tissue oxylipin profile in dairy cows with and without subclinical ketosis and assess the effects of oxylipins on adipocyte function in vitro. Subcutaneous adipose tissue from the flank (SAT) and visceral adipose tissue from the omentum (VAT) were collected through laparotomy from multiparous dairy cows (5-14 d in milk) and grouped according to blood β-hydroxybutyrate (BHB) into non-ketotic (NK; n = 5; BHB ≤ 0.8 mmol/L) and subclinical ketotic (SCK; n = 5; BHB 1.4 and ≤ 2.6 mmol/L). A targeted lipidome capable of detecting a 154 oxylipins was performed in paired SAT and VAT samples from all animals. Data were analyzed using the PROC GLIMMIX procedure in SAS (v9.4, SAS Institute Inc., Cary, NC, USA) for the effect of depot (SAT, VAT), ketosis status (SCK, NK), and their interaction (depot × ketosis status) on oxylipin abundance. The oxylipins thromboxane-B2 (TXB2), prostaglandin-A2 (PGA2), and 5-hydroxeicostretanoic acid (5-HETE) were selected from lipidomic data based on effects of ketosis status and depot-specificity to further investigate their effects on SAT and VAT adipocyte function. Lipidomic data revealed 50 oxylipins across both adipose tissue depots. SCK was associated with a decreased abundance of TXB2 and tended to associate with an increase in prostaglandinA2 (PGA2) and prostaglandinE1 (PGE1). Additionally, PGE1, 15-keto-prostaglandin-E2 (15-Keto-PGE2), 13,14-dihydro-15-keto-prostaglandin-E2 (13-14dh-15k-PGE2), 5-HETE, and 15-HETE were increased in SAT. While VAT had a greater abundance of 9,10-dihydroxy-12Z-octadecenoic acid (9,10-DiHOME), 12,13-dihydroxy-9Z-octadecenoic acid (12,13-DiHOME), 9-oxo-10E,12Z,15Z-octadecatrienoic acid (9-OxoOTrE) and 13S-hydroxy-9Z,11E,15Z-octadecatrienoic acid (13(s)-HOTrE). In vitro, AVG dose of 5-HETE on VAT cells tended to increase proliferation at d 7 compared with the control, HIGH dose of TXB2 tended to decrease lipid accumulation in SAT compared with control, and AVG dose of PGA2 on VAT cells tended to lower ROS compared with the control. Overall, postpartum dairy cows have depot-specific adipose tissue lipidomic profiles which are associated with changes in ketosis status.

Connections between Endometrial Health Status, Fatty Liver and Expression of Endocannabinoid System Genes in Endometrium of Postpartum Dairy Cows.

The endocannabinoid system (ECS) plays a crucial role in reproductive health, but its function in postpartum dairy cows remains poorly understood. This study investigated the expression patterns of ECS-related genes in the endometrium of postpartum dairy cows and their associations with endometrial health and the presence of fatty liver. Endometrial biopsies were collected from 22 Holstein Friesian cows at 4 and 7 weeks postpartum. Gene expression was analyzed using RT-qPCR, focusing on key ECS components including CNR2, MGLL, FAAH1, NAAA, NAPEPLD, PADI4 and PTGDS. The results reveal dynamic changes in ECS gene expression associated with endometritis and fatty liver. MGLL expression was significantly upregulated in cows with endometritis at 7 weeks postpartum, while NAAA expression was consistently downregulated in cows with fatty liver. CNR2 showed a time-dependent pattern in endometritis, and PTGDS expression was elevated in clinical endometritis at 4 weeks postpartum. The presence of fatty liver was associated with altered expression patterns of several ECS genes, suggesting a link between metabolic stress and endometrial ECS function. These findings indicate a potential role for the ECS in postpartum uterine health and recovery, offering new insights into the molecular mechanisms underlying reproductive disorders in dairy cows and paving the way for novel therapeutic approaches.

Association between IGF-1 and IGFBPs in Blood and Follicular Fluid in Dairy Cows Under Field Conditions.

Insulin-like growth factor 1 (IGF-1) regulates dairy cow reproduction, while the paracrine IGF system locally influences fertility. In both systems, IGF-1 bioactivity is regulated through binding proteins (IGFBPs) inhibiting IGF-1 binding to its receptor (IGF1R). This study aimed to investigate a possible transfer between this endocrine and paracrine system. Therefore, blood and follicular fluid (FF) from postpartum dairy cows were analysed for ß-hydroxybutyrate (BHB), IGF-1, IGFBP-2, -3, -4, -5, and an IGFBP fragment in two study parts. The mRNA expression of IGFBP-2, IGFBP-4, IGF1R, and the pregnancy-associated plasma protein A (PAPP-A) in granulosa cells was measured. The results showed correlations between plasma and FF for IGF-1 (r = 0.57, p < 0.001) and IGFBP-2 (r = -0.57, p < 0.05). Blood BHB negatively correlated with IGF-1 in blood and FF and IGFBP-3, -5 and total IGFBP in blood (IGF-1 plasma: r = -0.26, p < 0.05; FF: r = -0.35, p < 0.05; IGFBP-3: r = -0.64, p = 0.006; IGFBP-5: r = -0.49, p < 0.05; total IGFBP: r = -0.52, p < 0.05). A negative correlation was found between IGFBP-2 expression and IGF-1 concentration in FF (r = -0.97, p = 0.001), while an IGFBP fragment positively correlated with IGF1R-mRNA in FF (r = 0.82, p = 0.042). These findings suggest a transfer and local regulation between the somatotropic axis and the follicular IGF system, linking the metabolic status with local effects on dairy cow fertility.

The use of ultrasonography in the transition period to estimate adipose tissue depots and their association with risk of early postpartum hyperketonemia in Holstein dairy cattle

An elevated prepartum BCS is a risk factor for postpartum hyperketonemia (HYK) and elevated fatty acid (NEFA) concentrations in dairy cattle. The association between different adipose tissue depots, such as subcutaneous (SCAT) as well as visceral adipose tissue (VAT) depots and HYK and elevated NEFA concentrations remains unknown. The objective of this 2-part study was to describe SCAT and VAT depots using ultrasonography during the transition period and to associate them with metabolic markers of negative energy balance in early postpartum dairy cows. Multiparous Holstein cows were enrolled in a prospective observational cohort study with 2 cohorts in subsequent study years (Cohort 1: n = 31; Cohort 2: n = 28). At −6, −4, −2, and 2 wk relative to calving (Cohort 1) or −2 and 2 wk relative to calving (Cohort 2) BCS was determined and cows were examined via transcutaneous ultrasound at 6 locations for prediction of adipose tissue mass in 5 depots: 1) abdominal adipose tissue (AAT), 2) retroperitoneal adipose tissue (RPAT), 3) omental adipose tissue (OMAT), 4) mesenteric adipose tissue (MAT), and 5) subcutaneous adipose tissue (SCAT). Postpartum serum NEFA and BHB concentrations were determined twice weekly from 1 to 14 DIM. Cows were categorized as having HYK or high NEFA concentrations (NEFAH) if ≥1 sample resulted in a BHB ≥1.2 mmol/L or NEFA ≥720 µEq/L, respectively. Critical thresholds associated with HYK or NEFAH for each depot at −2 wk relative to calving and the time of maximum estimated depot size were evaluated using logistic regression and a receiver operator characteristic analysis. Abdominal AT increased from −6 to −2 wk relative to calving in cohort 1 but did not differ from −2 to 2 wk relative to calving. Subcutaneous AT did not change from −6 to −2 wk but decreased from −2 to 2 wk relative to calving in cohort 1 and 2. Omental AT accurately (AUC = 0.77) predicted HYK in cohort 1 but was non-informative for the prediction of HYK in cohort 2 (AUC = 0.49). Predicted AT depots were not informative for the prediction of NEFAH (AUC ≤0.59) in either cohort. Results from this study suggest that AT can be monitored during the transition period using the described technique; however, estimated prepartum AT depots at −2 wk relative to expected calving were inaccurate in distinguishing between postpartum NEFAH and non-NEFAH or HYK and non-HYK.

Altered bile acid and correlations with gut microbiome in transition dairy cows with different glucose and lipid metabolism status

The transition from pregnancy to lactation is critical in dairy cows. Among others, dairy cows experience a metabolic stress due to a large change in glucose and lipid metabolism. Recent studies revealed that bile acids (BA), besides being involved in both the emulsification and solubilization of fats during intestinal absorption, can also affect the metabolism of glucose and lipids, both directly or indirectly by affecting the gut microbiota. Thus, we used untargeted and targeted metabolomics and 16S rRNA sequencing approaches to investigate the concentration of plasma metabolites and BA, the composition of the rectum microbial community, and assess their interaction in transition dairy cows. In Experiment 1, we investigated BA and other blood parameters and gut microbiota in dairy cows without clinical diseases during the transition period, which can be seen as well adapted to the challenge of changed glucose and lipid metabolism. As expected, we detected an increased plasma concentration of β-hydroxybutyrate (BHBA) and nonesterified fatty acids (NEFA) but decreased concentration of glucose, cholesterol, and triglycerides (TG). Untargeted metabolomic analysis of the plasma revealed primary BA biosynthesis was one of the affected pathways, and was consistent with the increased concentration of BA in the plasma. A correlation approach revealed a complex association between BA and microbiota with the host plasma concentration of glucose and lipid metabolites. Among BA, chenodeoxycholic acid derivates such as glycolithocholic acid, taurolithocholic acid, lithocholic acid, taurochenodeoxycholic acid, and taurodeoxycholic acid were the main hub nodes connecting microbe and blood metabolites (such as glucose, TG, and NEFA). In Experiment 2, we investigated early postpartum dairy cows with or without hyperketonemia (HPK). As expected, HPK cows had increased concentration of NEFA and decreased concentrations of glucose and triglycerides. The untargeted metabolomic analysis of the plasma revealed that primary BA biosynthesis was also one of the affected pathways. Even though the BA concentration was similar among the 2 groups, the profiles of taurine conjugated BA changed significantly. A correlation analysis also revealed an association between BA and microbiota with the concentration in plasma of glucose and lipid metabolites (such as BHBA). Among BA, cholic acid and its derivates such as taurocholic acid, tauro α-muricholic acid, and taurodeoxycholic acid were the main hub nodes connecting microbe and blood metabolites. Our results indicated an association between BA, intestinal microbe, and glucose and lipid metabolism in transition dairy cows. These findings provide new insight into the adaptation mechanisms of dairy cows during the transition period.

Isolation and morphological identification of fungi from endometrial samples of postpartum dairy cows

Numerous studies on endometritis of postpartum dairy cows describe the bacterial aetiology of the condition. However, studies on fungal agents causing inflammatory conditions of the reproductive tract are limited. The objective of the present study was to identify the mycotic isolates from the reproductive tract of postpartum dairy cows and analyse their susceptibility to antifungal agents. In this study, 70 endometrial cytobrush samples were collected from dairy cows 40 - 120 days postpartum (dpp) and cultured in Sabouraud dextrose agar (SDA). The isolated fungal cultures were identified by Lactophenol Cotton Blue staining and were subjected to antifungal susceptibility testing. The frequency of isolation of fungi from endometrial samples was 15.71 per cent (11/70). Aspergillus niger was isolated from four (33.33%) samples, followed by Penicillium spp. (25%), Aspergillus fumigatus (16.67%), Mucor spp. (16.67%) and Absidia spp. (8.33%). Antifungal susceptibility testing revealed that 50 per cent of the isolates were susceptible to fluconazole, whereas only 25 per cent of the isolates were completely resistant to amphotericin-B. The prevalence of fungal infection in reproductive tract was higher in cows with an age of ≥ 5 years and a parity of ≥ 2, though this was not significant. A significantly higher number of cattle with history of intrauterine antibiotic therapy were positive for fungal culture. However, the association between prevalence of fungi and reproductive complications was statistically non-significant. Keywords: Postpartum dairy cows, fungal infections, Aspergillus niger, mycotic infections

Progesterone profiles in postpartum dairy cows with inflammatory disorders

The objective of this prospective cohort study was to determine if progesterone (P4) profiles differed between dairy cows with or without inflammatory disorders early postpartum. A total of 708 cows from 2 commercial herds were enrolled 3 wk before parturition and examined for clinical health disorders (difficult calving, retained placenta, metritis, displaced abomasum, mastitis, or lameness) until 5 wk postpartum. Serum haptoglobin (Hp) was measured in blood at 2 and 6 DIM (range ±2 d); metritis was assessed at 4, 8, 11, and 15 DIM; and purulent vaginal discharge and endometritis (≥6% PMN in endometrial cytology sampled by cytobrush) were assessed at 35 ± 3 DIM. As Hp ≥0.8 g/L or endometritis were associated with ovarian dysfunction in previous studies, cows with serum Hp ≥0.8 g/L at either time point and endometritis, regardless of clinical disease, were classified as the cohort with inflammatory disorders (INFLAM; n = 139). Clinically healthy cows without difficult calving, with singleton birth, with Hp <0.8 g/L at both sampling times, without endometritis or purulent vaginal discharge, and BCS ≥3.00 (1 to 5 scale) were classified as healthy (n = 133). Cows with only one of the 2 conditions (high Hp or endometritis) were excluded. Cohorts had serum P4 measured twice weekly from 35 to 70 DIM (±3 d), and the first detected luteal phase (LP) during the sampling period was defined as the period from onset of luteal activity (P4 increase to ≥1 ng/mL) until decline of P4 to <1 ng/mL. The odds of prolonged LP (≥21 d long), average LP length, peak P4, and time to P4 decline (hazard rate) were analyzed using multivariable mixed logistic, linear, or Cox proportional hazard regression models including INFLAM status, parity, sampling day (when applicable), and herd as a random effect considering the covariates of season, milk yield at first DHIA test, and DIM at onset of cyclicity or LP length (when applicable). Cows with INFLAM had greater odds of prolonged LP (LSM ± SEM; 67% vs. 37% ± 7%), greater average LP length (17 vs. 15 ± 2 d), lesser P4 at d 4 (4.6 vs. 5.5 ± 0.3 ng/mL) and d 7 (6.0 vs. 7.7 ± 0.3 ng/mL) of the LP, and lesser peak P4 (6.9 vs. 8.2 ± 0.3 ng/mL) during the LP than healthy cows. Status of INFLAM was associated with time to P4 decline in multiparous but not primiparous cows; the LP of INFLAM multiparous cows was less likely to have luteolysis (P4 decline) by d 14 (adjusted hazard ratio [AHR] and 95% CI: 0.54; 0.31 to 0.94) or by d 21 (AHR: 0.32; 0.12 to 0.84) than in healthy multiparous cows. In conclusion, postpartum cows with markers of systemic inflammation at wk 1 and uterine inflammation at wk 5 had altered luteal function (prolonged LP and lower P4 concentrations) before first breeding, which is a possible pathway linking postpartum health disorders and reduced fertility.

Evaluating differences in milk production, reproductive performance, and survival associated with vaginal discharge characteristics and fever in postpartum dairy cows

The objective was to assess differences in productive and reproductive performance, and survival associated with vaginal discharge characteristics and fever in postpartum dairy cows located in Western and Southern states of the U.S.A. This retrospective cohort study included data from 3 experiments conducted in 9 dairies. Vaginal discharge was evaluated twice within 12 DIM and scored on a 5-point scale. The highest score observed for each cow was used for group assignment (VD group) as follows: VD 1 and 2 (VD 1/2; n = 1,174) = clear mucus/lochia with or without flecks of pus; VD 3 (n = 1,802) = mucopurulent with < 50% pus; VD 4 (n = 1,643) = mucopurulent with ≥50% of pus or non-fetid reddish/brownish mucous, n = 1,643; VD 5 = fetid, watery, and reddish/brownish, n = 1,800. All VD 5 cows received treatment according to each herd's protocol. Rectal temperature was assessed in a subset of VD 5 cows, and subsequently divided into Fever (rectal temperature ≥39.5°C; n = 334) and NoFever (n = 558) groups. A smaller proportion of cows with VD 5 (67.6%) resumed ovarian cyclicity compared with VD 1/2 (76.2%) and VD 4 (72.9%) cows; however, a similar proportion of VD5 and VD 3 (72.6%) cows resumed ovarian cyclicity. A smaller proportion of VD 5 (85.8%) cows received at least one artificial insemination (AI) compared with VD 1/2 (91.5%), VD 3 (91.0%), or VD 4 (91.6%) cows. Although we did not detect differences in pregnancy at first AI according to VD, fewer cows with VD 5 (64.4%) were pregnant at 300 DIM than cows with VD 1/2 (76.5%), VD 3 (76.2%), or VD 4 (74.7%). Hazard of pregnancy by 300 DIM was smaller for VD 5 compared with VD 1/2, VD 3, or VD 4 cows. A greater proportion of VD 5 cows were removed from the herd within 300 DIM compared with other VD groups. There was 760 kg lesser milk production within 300 DIM for VD 5 compared with VD 2, VD 3, and VD 4, whereas VD 2, VD 3, and VD 4 had similar milk production. We did not detect an association between fever at diagnosis of VD 5 and reproductive performance or milk production. A greater proportion of VD 5 cows without fever were removed from the herd by 300 DIM compared with VD 5 cows with fever. Differences in productive and reproductive performance, and removal of the herd were restricted to fetid, watery, and reddish/brownish vaginal discharge, which was independent of fever.

Specificity of two peripartum blood markers for early lactation acute uterine inflammation in pasture-fed, seasonal-calving dairy cows.

A delayed recovery of the reproductive tract from natural inflammatory processes associated with postpartum involution will compromise further reproductive function. Following a literature review, we selected serum amyloid A (SAA) and α1-acid glycoprotein (α1-AGP) to assess as potential circulating markers of acute uterine inflammation, as concentrations of these 2 acute phase proteins were reported to be elevated early postpartum in dairy cows with active uterine infection. Convenience serum samples from an induced model of uterine infection were used to measure concentrations of these markers. Infection was induced by infusing either 107 or 109 cfu of Trueperella pyogenes (n = 9 cows each; bacteria group n = 18) or saline as a control (n = 18) into the uterus at 48 d postpartum. Although infection stimulated an increase in uterine polymorphonuclear neutrophils, SAA and α1-AGP concentrations in serum were not different between infusion groups. Cows were subsequently classified into uterine health groups based on the presence of endometritis, with or without the presence of T. pyogenes in uterine culture in response to uterine infusion. Mean SAA concentrations were greater in cows that were either endometritis negative – infection positive (n = 9), endometritis positive – infection negative (n = 5), or endometritis positive – infection positive, compared with the endometritis negative – infection negative (n = 11) cows. There was no difference between uterine health groups for α1-AGP concentrations. Mean SAA and α1-AGP concentrations changed over time, reaching maximum concentrations on d 3 and 7 post-infusion, respectively, before decreasing thereafter to d 17 post-infusion.

Oestrus induction and fertility response in post-partum anoestrus dairy cows treated with homeopathic medicine

The study was carried out to evaluate the effect of two homeopathic medicines to induce oestrus in 36 postpartum anoestrus crossbred Jersey dairy cows. Group 1 cows were fed a mineral mixture, and group 2 and 3 were medicated with Pulsatilla and Sepia drenched at the dose rate of 20 mL twice daily for 8 days, respectively. The mean plasma progesterone level (ng/mL) estimated using a radio immunoassay kit was significantly higher in group 2, followed by group 3 before and after medication on day 28 and 60, post artificial insemination (AI). Out of 12 induced for oestrus, 10 cows (83.33 %) and 9 cows (75.0 %) in group 2 and 3 were confirmed pregnant by rectal palpation on day 60 post AI, respectively. Both the homeopathic medicines showed 100% oestrus induction with a mean interval of 25.17 to 25.50 days, and Pulsatilla medicated cows showed improved fertility response than Sepia. The significantly higher level of progesterone after the withdrawal of homeopathic medication might be due to the release of circulating hormone, which blocks estradiol negative feedback. The subsequent increase reduces uterine PGF2 alpha secretion for a better conception rate.

Repeated inoculation with rumen fluid accelerates the rumen bacterial transition with no benefit on production performance in postpartum Holstein dairy cows

BackgroundThe dairy cow’s postpartum period is characterized by dramatic physiological changes, therefore imposing severe challenges on the animal for maintaining health and milk output. The dynamics of the ruminal microbiota are also tremendous and may play a crucial role in lactation launch. We aim to investigate the potential benefits of early microbial intervention by fresh rumen microbiota transplantation (RMT) and sterile RMT in postpartum dairy cows. Twelve fistulated peak-lactation dairy cows were selected to be the donors for rumen fluid collection. Thirty postpartum cows were divided into 3 groups as the transplantation receptors respectively receiving 10 L fresh rumen fluid (FR), 10 L sterile rumen fluid (SR), or 10 L saline (CON) during 3 d after calving.ResultsProduction performance, plasma indices, plasma lipidome, ruminal microbiome, and liver transcriptome were recorded. After fresh and sterile RMT, we found that the molar proportion of propionic acid was increased on d 7 in the FR and SR groups and the bacterial composition was also significantly changed when compared with the CON group. A similarity analysis showed that the similarities between the CON group and FR or SR group on d 7 were 48.40% or 47.85%, whereas the similarities between microbiota on d 7 and 21 in the FR and SR groups were 68.34% or 66.85%. Dry matter intake and feed efficiency were not affected by treatments. Plasma β-hydroxybutyrate concentration in the FR group was decreased and significantly different lipids mainly included phosphatidylcholine and lysophosphatidylcholine containing polyunsaturated fatty acids. Hepatic transcriptomics analysis indicated acute-phase response pathways were upregulated in the SR group.ConclusionsOur study suggests that RMT can shorten the transition process of the ruminal microbiota of postpartum dairy cows with no benefit on dry matter intake or feed efficiency. Inoculation with rumen fluid may not be a useful approach to promote the recovery of postpartum dairy cows.Graphical

Endometrial DNA methylation signatures during the time of breeding in relation to the pregnancy outcome in postpartum dairy cows fed a control diet or supplemented with rumen-protected methionine.

Post calving metabolic stress reduces the fertility of high producing dairy cows possibly by altering the expression of genes in the maternal environment via epigenetic modifications. Therefore, this study was conducted to identify endometrial DNA methylation marks that can be associated with pregnancy outcomes in postpartum cows at the time of breeding. For this, twelve days post-calving, cows were either offered a control diet or supplemented daily with rumen-protected methionine. Cows showing heat 50-64days postpartum were artificially inseminated. Endometrial cytobrush samples were collected 4-8h after artificial insemination and classified based on the pregnancy out comes as those derived from cows that resulted in pregnancy or resulted in no pregnancy. The DNAs isolated from endometrial samples were then subject to reduced representative bisulfite sequencing for DNA methylation analysis. Results showed that in the control diet group, 1,958 differentially methylated CpG sites (DMCGs) were identified between cows that resulted in pregnancy and those that resulted in no pregnancy of which 890 DMCGs were located on chr 27: 6217254-6225600bp. A total of 537 DMCGs were overlapped with 313 annotated genes that were involved in various pathways including signal transduction, signalling by GPCR, aldosterone synthesis and secretion. Likewise, in methionine supplemented group, 3,430 CpG sites were differentially methylated between the two cow groups of which 18.7% were located on Chr27: 6217254-6225600bp. A total of 1,781 DMCGS were overlapped with 890 genes which involved in developmental and signalling related pathways including WNT-signalling, focal adhesion and ECM receptor interaction. Interestingly, 149 genes involved in signal transduction, axon guidance and non-integrin membrane-ECM interactions were differentially methylated between the two cow groups irrespective of their feeding regime, while 453 genes involved in axon guidance, notch signalling and collagen formation were differentially methylated between cows that received rumen protected methionine and control diet irrespective of their fertility status. Overall, this study indicated that postpartum cows that could potentially become pregnant could be distinguishable based on their endometrial DNA methylation patterns at the time of breeding.

Incidence of uterine infections, major bacteria and antimicrobial resistance in postpartum dairy cows in southern Ethiopia

BackgroundUterine infections, primarily caused by bacterial pathogens, pose a significant problem for dairy farmers worldwide, leading to poor reproductive performance and economic losses. However, the bacteria responsible for uterine infections have not been adequately studied, nor has the antibiotic susceptibility of the causative bacteria been frequently tested in Ethiopia. This study aims to estimate the cumulative incidence of uterine infections in postpartum dairy cows, identify bacterial causes and determine antimicrobial susceptibility profile of the isolated bacteria.MethodsA prospective cohort study was conducted in which 236 cows from 74 dairy farms were monitored biweekly from calving to 90 days postpartum for metritis, endometritis and other disorders. Aseptic uterine swab samples were collected from 40 cows with uterine infections. The samples were cultured, and the isolated bacteria were tested for antimicrobial susceptibility using the disk diffusion method.ResultsOut of 236 cows monitored during the postpartum phase, 45 (19.1%) were found to have contracted uterine infection. The cumulative incidence of metritis was 11.4% (n = 27), while the cumulative incidence of endometritis was 7.6% (n = 18). Of the 40 cultured swab samples, 29 (72.5%) had one or more bacteria isolated. The most commonly isolated bacteria were Escherichia coli (45%), coagulase-positive staphylococci (30%), and Klebsiella spp. (22.5%). Other bacterial spp, including Arcanobacterium pyogenes (12.5%), Fusobacterium spp. (12.5%), Enterobacter aerogenes (12.5%), coagulase-negative staphylococci (12.5%), Streptococcus spp. (7.5%), Salmonella spp, (5%) Proteus spp (5%) and Pasteurella spp (2.5%) were also isolated. All of the isolated bacteria demonstrated resistance to at least one of the antimicrobials tested. Multidrug resistance was observed in E. coli, Klebsiella spp., A. pyogenes, and Fusobacterium spp. Gentamicin was found to be the most effective antimicrobial against all bacteria tested, while tetracycline was the least effective of all.ConclusionThe study found that a significant proportion of cows in the population were affected by uterine infections and the isolated bacteria developed resistance to several antimicrobials. The study emphasizes the need for responsible use of antimicrobials to prevent the emergence of antimicrobial resistance. It also highlights the importance of raising awareness among dairy farmers to avoid the indiscriminate use of antibiotics and its consequences.

Customized modified therapies for ovarian cyst and persistent follicle followed with TAI in early postpartum dairy cows.

Postpartum ovarian dysfunction [ovarian cyst (OC) and persistent follicle (PF)] has been an important issue. Finding effective hormonal treatments to improve reproductive performance in dairy cows has become a necessity. Improve reproductive performance and ovarian activity in postpartum cows with specific customized treatment for OC and PFs. The study included 48 cows at 14 days P.P, which received two dosages of 500 μg IM cloprostenol, 14 days apart as presynchronization protocol. Ultrasound ovarian scans 14 days after the last injection for 4 weeks. The cows were divided into three groups according to ovarian status: OC (n = 14), PF (n = 12), and NE (n = 22). In the OC group, received 500 μg IM cloprostenol and 100 μg IM cystoriline, a second dose of cloprostenol 14 days later and a second dose of cystoriline 36 hours later, and AI after 24 hours (GnRH+ PG/PG/GnRH). In the PF group, was fitted with progesterone-releasing intravaginal device (PRID) for 9 days; the same day, they received 100 μg cystoreline then 500 μg cloprostenol 7 days later, after PRID removal AI 56 hours later (PRID + GnRH/PG). In the NE group, artificial insemination was implemented until 28 days depending on estrus detection. The ovarian activity was greatly affected by the customized treatments, leading to enhanced follicular and luteal activity, particularly after the PGF2α injection. The OC and PF groups showed substantial estrus responses of 71.43% and 75.02%, respectively, during AI time. While the NE group had an ovulation rate of 54.5% and a pregnancy rate of 31.8%, the treatment groups showed marked improvements in reproductive performance. The ovulation rates in the OC and PF groups were 71.43% and 75% and the pregnancy rates at the 1st artificial insemination were 64.28% and 66.7%. Improving reproductive performance and minimizing the time to first service are possible advantages of early case-specific treatment for postpartum cows with OC and PFs.

Benefícios da suplementação com disseleneto de difenila em vacas leiteiras no período de transição: efeitos metabólicos, imunes e antioxidantes

ABSTRACT The aim of this study was to evaluate the effects of diphenyl diselenide (PhSe) supplementation during the transition period on the metabolism, immunity, oxidative status, and milk production of postpartum dairy cows. Twenty-seven Holstein females were divided into groups: (PhSe) (DDG), which received 3 μmol/kg of (PhSe)2 in 4 mL of dimethyl sulfoxide (DMSO) subcutaneously, DMSO (DMSOG), and NaCl (NACLG) which received 4 mL of DMSO and 0.9% NaCl. Evaluation of body condition score (BCS), weighing and administrations were performed at 42, 28, and 14 days prepartum, and on the day of calving (0). On days 0, 7, 14, 21, and 35 postpartum, BCS was evaluated, and blood were collected. Colostrum was obtained from the first postpartum milking. Production was measured, and milk was collected on days 7, 14, 21, and 35 postpartum. DDG showed higher values of total protein (TP) and globulins (GLOB) 7 days postpartum and increase from day 0 to days 21 and 35. DDG immunoglobulin G (IgG) was higher on days 21 and 35, and increased between days 7 and 21. In postpartum TP, GLOB and IgG are physiologically reduced, therefore, the results indicate that supplementation of transition females with (PhSe) stimulated postpartum humoral immunity.

Supplementation of Multistrain Probiotics Improves Milk Production, Blood Metabolites, Digestibility, and Rectal Microbiota during the Prepartum and Early Lactation Stages in Crossbred Cows

The current study aimed to study the effects of administration with a multistrain probiotic formulation (MPF) initiated from the prepartum stage on lactation performance, digestibility, rectal microbiota, and blood metabolites of postpartum dairy cows. A total of 30 multiparous crossbred (Holstein Friesian × Balady) dairy cows were randomized into three groups: control (no MPF supplementation), MPF1 (0.5 g MPF/cow/d), and MPF2 (1 g MPF/cow/d). The administration of MPF started 28 days before calving and continued for 84 days after. The results revealed that cows in the MPFI and MPF2 groups had higher milk production, 3.5% FCM, and ECM than those in the control group. The MPF‐supplemented cows had significantly greater milk energy output, DMI, and yields of solids‐not‐fat, lactose, total solids, ash, fat, and protein. The MPF supplementation significantly enhanced feed conversion and significantly interacted with milk solids‐not‐fat, lactose, total solids, and protein. Hematological indicators did not significantly alter between the MPF and control groups. However, cows receiving MPF supplements had higher levels of Hct. Serum biochemical measurements showed lower serum concentrations of LDL, total cholesterol, and VLDL in MPF‐fed cows than in the control group. The digestibility of organic and dry matter tended to be higher in MPF‐supplemented cows. The populations of lactobacillus, bacillus, and total bacterial count increased due to MPF administration, while the count of Clostridium, Salmonella, E. coli, and coliforms decreased in MPF‐fed cows. In summary, administering MPF during late gestation and early lactation period improved milk production, fecal microbial composition, and overall health of dairy cows.