Subclinical endometritis in estrual buffaloes: diagnosis, prevalence and impact on reproductive performance.

The study evaluated the reliability of polymorphonuclear (PMN) cell count in endometrial cytology by cytobrush technique as a diagnostic for subclinical endometritis (SCE) at the time of estrus and its relationship with bacterial presence and fertility in buffaloes. Healthy pluriparous buffaloes (n = 115) were subjected to endometrial sampling by cytobrush technique (for cytology and bacterial isolation) and ultrasonography of genitalia prior to insemination at the time of spontaneous estrus. Buffaloes were inseminated at the same estrus and were confirmed for pregnancy by ultrasonography at day 40 post-insemination. Growth of aerobic bacteria was recorded in 26.1% (30/115) of estrual buffaloes. Bacteria of eight distinct genera (Staphylococcus spp., Bacillus spp., Proteus spp., Escherichia coli, Klebsiella spp., Streptococcus spp., Pseudomonas spp. and T. pyogenes) were isolated. Presence of bacterial infection was considered as the standard, against which PMN threshold for SCE was calculated by receiver operator curve (ROC). The PMN count of ≥ 5% with good sensitivity (66.7, 95% CI 50.9-81.4) and specificity (87.0%, 95% CI 78.0-94.6) with an overall high diagnostic accuracy (81.7%) for predicting SCE was obtained. Based on calculated PMN threshold, buffaloes were divided into subclinical endometritic (SCE; ≥ 5% PMNs) and control (< 5% PMNs) groups. Thirty-one buffaloes (27.0%, 31/115) had ≥ 5% PMNs in the endometrial cytology at estrus. Ultrasonographic evaluation showed that size of largest follicle, endometrial thickness, and uterine horn diameter did not differ significantly (P > 0.05) between the two groups. Significantly, lower conception rate (22.58 vs 36.90%, P < 0.05) for first artificial inseminations (AIs) and significantly higher number of AIs per pregnancy (2.81 ± 0.27 vs 1.75 ± 0.15, P < 0.05) were recorded in SCE compared to control group. The results indicated that cytobrush based endometrial cytology with 5% PMN cut-off value has a good accuracy for predicting subclinical endometritis at estrus in buffaloes.

Uterine blood flow during various stages of pregnancy in dairy buffaloes using transrectal Doppler ultrasonography.

Reference data to assess function and perfusion of uteroplacental tissues by assessment of uterine blood flow parameters is not available in buffaloes. The objective of the present study was to assess and quantify blood flow parameters at various stages of gestation. A total of 54 Murrah buffaloes, six animals at every month of gestation, from two months to ten months, were subjected to transrectal Doppler ultrasonography to assess uterine blood flow in both the middle uterine arteries. Resistance and pulsatility indices, velocity and volume of blood flow, diameter of the artery and notch signal were measured for different waveforms. The resistance index value was positively correlated with pulsatility index (r=0.94, P<0.05) but negatively correlated with all other parameters for both arteries, ipsilateral and contralateral to the fetus. With a significant advancement of pregnancy, there was reduction in resistance index with a significant increase in velocity, volume of blood flow and diameter in both arteries. There was a significant increase in the volume and velocity of blood flow (P<0.05) during the last trimester with increased growth demands of the fetus. The notch signal disappeared by 20-24 weeks. Thus, transrectal Doppler ultrasongraphy proved to be a useful non-invasive method to assess the uterine blood flow during pregnancy in buffaloes. This could be a valuable tool to ascertain hemodynamic changes in complicated pregnancy (e.g. abnormalities in uterine blood flow/placenta/fetus) and its extent of deviation from normal.