Epigenetic inheritance of diet-induced and sperm-borne mitochondrial RNAs.

Spermatozoa harbour a complex and environment-sensitive pool of small non-coding RNAs (sncRNAs)1, which influences offspring development and adult phenotypes1-7. Whether spermatozoa in the epididymis are directly susceptible to environmental cues is not fully understood8. Here we used two distinct paradigms of preconception acute high-fat diet to dissect epididymal versus testicular contributions to the sperm sncRNA pool and offspring health. We show that epididymal spermatozoa, but not developing germ cells, are sensitive to the environment and identify mitochondrial tRNAs (mt-tRNAs) and their fragments (mt-tsRNAs) as sperm-borne factors. In humans, mt-tsRNAs in spermatozoa correlate with body mass index, and paternal overweight at conception doubles offspring obesity risk and compromises metabolic health. Sperm sncRNA sequencing of mice mutant for genes involved in mitochondrial function, and metabolic phenotyping of their wild-type offspring, suggest that the upregulation of mt-tsRNAs is downstream of mitochondrial dysfunction. Single-embryo transcriptomics of genetically hybrid two-cell embryos demonstrated sperm-to-oocyte transfer of mt-tRNAs at fertilization and suggested their involvement in the control of early-embryo transcription. Our study supports the importance of paternal health at conception for offspring metabolism, shows that mt-tRNAs are diet-induced and sperm-borne and demonstrates, in a physiological setting, father-to-offspring transfer of sperm mitochondrial RNAs at fertilization.

Effect of prostaglandin alone and in combination with trace minerals on the follicular and luteal dynamics, estrus response and pregnancy in sub-estrus buffaloes (Bubalus bubalis).

Sub-estrus is a condition when buffaloes do not display behavioural estrus signs, despite being in estrus and causes a delay in conception and increases the service period. The present study describes the effect of synthetic prostaglandin (PGF2α) alone and in combination with trace minerals on the follicular and corpus luteum (CL) dynamics, serum estradiol (E2) and progesterone (P4) concentration correlating estrus response and pregnancy outcome in sub-estrus buffaloes during the breeding season. A total of 50 sub-estrus buffaloes, identified through ultrasonography (USG) examination, were randomly allocated into three groups, viz. T1 (Synthetic PGF2α, Inj. Cloprostenol 500 µg, i.m, n = 17), T2 (Synthetic PGF2α + Trace mineral supplementation, Inj. Stimvet 1 mL/100 kg body weight, i.m., n = 17) and control (untreated; n = 16). Following treatment, 100% of sub-estrus buffaloes were induced estrus in the T1 and T2 groups, while only 18.75% were induced in the control. The CL diameter and serum P4 concentration were significantly lower at post-treatment, whereas the pre-ovulatory follicle (POF) size and serum E2 concentration were significantly higher in the T1 and T2 groups as compared to the control (p < .05). The buffaloes of the T2 group had a greater proportion of moderate intensities estrus than those of T1. Moreover, the proportion of buffaloes conceived in the T1 and T2 were 41.2% and 52.95%, respectively. The larger POF diameter and higher serum E2 concentration were associated with intense intensity estrus and higher conception rate (66.7%) in sub-estrus buffaloes. Similarly, CL regression rate, POF size and serum E2 concentration were relatively higher in the buffaloes conceived as compared to those not conceived. It is concluded that synthetic PGF2α in combination with trace minerals induces moderate to intense intensities estrus in a greater proportion of sub-estrus buffaloes and increases the conception rate during the breeding season. Moreover, behavioural estrus attributes correlating follicle and luteal morphometry, serum E2 and P4 concentration could be used to optimise the breeding time for augmenting the conception rate in sub-estrus buffaloes.

Exploration of allelic variants in short tandem repeats (STRs) flanking milk production QTLs and their association with milk production traits in Indian water buffaloes.

Short tandem repeats (STRs) are co-dominant, highly polymorphic marker loci, distributed throughout the genome and useful for identification and mapping of QTLs associated with variation in traits of economic significance. Allelic variants were identified in STRs located in close vicinity of cattle QTLs for milk production,, viz. BMS713, BM6404, BM4513, BM121, BM6105, TGLA245, BL1100, BMS1948, BMS711, BM1443, BM1706, BM6438, BM143, BM415, ETH131, ETH 2, and BM1329 in 109 water buffaloes of Murrah breed. All loci except TGLA245 exhibited polymorphism of varying degree. The observed number of alleles, effective number of alleles, PIC value, observed heterozygosity, and expected heterozygosity across all STR loci averaged 4.12 ± 0.22, 3.20 ± 0.22, 0.60 ± 0.04, 0.34 ± 0.05, and 0.66 ± 0.03, respectively. Goodness of fit (chi-square) and likelihood ratio (G square) test demonstrated that the population exhibited a deviation from HWE for all the loci. FIS was positive and ranged from 0.22 to 1.00. Least square analysis of variance exhibited significant effects of BM4513, ETH131, BM713, and BM6105 on first lactational total lactation milk yield, 305-day milk yield, lactation length, and dry period respectively. None of the STRs could exhibit significant effect on peak yield.

Genetic control of non-genetic inheritance in mammals: state-of-the-art and perspectives.

Thought to be directly and uniquely dependent from genotypes, the ontogeny of individual phenotypes is much more complicated. Individual genetics, environmental exposures, and their interaction are the three main determinants of individual's phenotype. This picture has been further complicated a decade ago when the Lamarckian theory of acquired inheritance has been rekindled with the discovery of epigenetic inheritance, according to which acquired phenotypes can be transmitted through fertilization and affect phenotypes across generations. The results of Genome-Wide Association Studies have also highlighted a big degree of missing heritability in genetics and have provided hints that not only acquired phenotypes, but also individual's genotypes affect phenotypes intergenerationally through indirect genetic effects. Here, we review available examples of indirect genetic effects in mammals, what is known of the underlying molecular mechanisms and their potential impact for our understanding of missing heritability, phenotypic variation. and individual disease risk.

Binge drinking, HIV/HPV co-infection risk, and HIV testing: Factors associated with HPV vaccination among young adults in the United States.

Human papillomavirus (HPV) is a common sexually transmitted infection. Binge drinkers often engage in HIV/HPV co-infection high-risk behaviors. We examined the association between binge drinking, HIV/HPV co-infection risk, HIV testing and HPV vaccination among young adults. Data from the 2017 Behavioral Risk Factor Surveillance System survey were examined. Participants (N = 430/450,016; 0.11%) were HPV vaccine-eligible young adults ages 18-26 years. Multivariable logistic regression examined the association between binge drinking in the past 30 days, HIV/HPV co-infection high-risk risk behaviors, HIV testing, and HPV vaccination (initiated/completed, unvaccinated) among young adults. Respondents were primarily cisgender (99.8%), non-Hispanic White (41.4%), employed (46.2%) or student (35.4%), and insured (68.2%). Most did not binge drink (55.2%). The majority did not engage in HIV/HPV co-infection high-risk risk behaviors (78.2%). More than one-half had never been tested for HIV (59%) nor vaccinated against HPV (60.6%). Although binge drinkers (44.8%) were significantly more likely to engage in HIV/HPV co-infection high-risk behaviors (OR = 2.1; 95% CI: 1.0-4.5), binge drinking was not positively associated with HIV testing (OR = 0.98; 95% CI: 0.63-1.53). After adjusting for demographics and HIV/HPV co-infection high-risk behaviors, one (aOR = 2.71; 95% CI: 1.11-6.65) and two episodes (aOR = 3.05; 95% CI: 1.26-7.41) of binge drinking in the past 30 days were significantly associated with HPV vaccination uptake. Positive associations between HPV vaccination and participants having an HIV test in 2017 (aOR = 3.86; 95% CI: 1.42-10.55) and before 2017 (aOR = 2.62; 95% CI: 1.23-5.56) were also statistically significant. Because young adult binge drinkers are more likely to engage in HIV/HPV co-infection high-risk behaviors, promoting HPV vaccination and HIV testing are important public health objectives.

Glaucoma awareness Indian military personnel: a tri-service study.

INTRODUCTION: In India, glaucoma is the third most common cause of blindness, reflecting both its asymptomatic presentation and a lack of knowledge in the general population. No previous published data of glaucoma awareness among the Indian Armed forces personnel exists, who constitute a unique group consisting of people drawn from all parts of the country and society. METHODS: Bilingual questionnaires were distributed to 496 serving Army, Navy and Air Force personnel serving in units local to the Zonal military hospital in North India. Having heard of the term glaucoma resulted in the subject being 'glaucoma aware', while 'knowledge of glaucoma' required at least three out of six questions to be answered correctly. RESULTS: 110/496 (22%) participants were found to be glaucoma aware, while knowledge of glaucoma was found in 60/496 (12%) participants. CONCLUSIONS: This study demonstrates that glaucoma awareness and knowledge is high compared with rural or urban Indian populations. This is likely reflects the frequent health camps conducted by the armed forces and periodic medical examinations. However, these figures are still low compared with developed countries and likely reflects differences in education standards, socioeconomic status and differing influences of the media.

Evaluation and comparison of early hemodynamic changes after elective mitral valve replacement in patients with severe and mild pulmonary arterial hypertension.

OBJECTIVE: To evaluate and compare early hemodynamic changes after elective mitral valve replacement (MVR) in patients with severe and mild pulmonary arterial hypertension (PAH). DESIGN: A prospective observational study. SETTING: University-affiliated hospital. PARTICIPANTS: Sixty patients undergoing elective MVR. INTERVENTIONS: The patients were divided into 2 equal groups based on the presence (group A) or absence (group B) of severe PAH defined as systolic pulmonary artery pressure (PAP) > or = 50 mmHg on preinduction pulmonary artery catheterization. Thiopental, fentanyl, midazolam, isoflurane, and rocuronium (or vecuronium if the heart rate >100 beats/min) were used for the induction and maintenance of anesthesia. MVR was performed using standard cardiopulmonary bypass (CPB) techniques. The therapy for PAH was electively instituted in all patients with a nitroglycerin infusion (0.5-1 microg/kg/min), deliberate hypocarbia (arterial carbon dioxide tension < or = 35 mmHg), fractional inspired oxygen concentration = 1.0, and elective ventilation for at least 12 hours in the postoperative period. Hemodynamic and arterial blood gas parameters were serially measured before induction; after intubation; after termination of CPB; after extubation; and at 6, 24, and 48 hours after surgery. Differences in these parameters were analyzed within and among the groups using appropriate statistical tests. MEASUREMENTS AND MAIN RESULTS: The mean CPB and aortic cross-clamp times were similar in the 2 groups (78 +/- 33 and 50 +/- 21 minutes in group A and 63 +/- 32 and 41 +/- 23 minutes in group B). The mean PAP, pulmonary capillary wedge pressure, and pulmonary vascular resistance decreased significantly soon after CPB in both groups (p < 0.001), but the decrease was significantly lower in group A (p < 0.001). The mean PAP approached near-normal values in group A (23 +/- 8 mmHg) and normal values in group B (16 +/- 6 mmHg) immediately postoperatively. There was an increase in cardiac index (p < 0.01) after CPB in group A. A relative improvement in oxygenation occurred after MVR in group A compared with group B (p < 0.001). Patients in group A were ventilated for a longer duration (25.9 +/- 18.8 v 17.3 +/- 7.9 hours, p < 0.05). There was no significant difference in the inotropic requirement between the 2 groups. There was no mortality in either group. CONCLUSIONS: PAP returns to near-normal values in patients with severe preoperative PAH and to normal values in patients with mild preoperative PAH immediately after MVR. The outcome after surgery in patients with severe PAH is comparable to those with mild PAH.

Perioperative management of a patient with Dandy Walker malformation with tetralogy of Fallot undergoing total correction and fresh homologous pericardial pulmonary valve conduit implantation: Report of a rare case.

Perioperative management of a patient with Dandy-Walker malformation (DWM) with tetralogy of Fallot (TOF), patent ductus arteriosus, and pulmonary artery stenosis is a great challenge to the anesthesiologist. Anesthetic management in such patients can trigger tet spells that might rapidly increase intracranial pressure (ICP), conning and even death. The increase in ICP can precipitate tet spells and further brain hypoxia. To avoid an increase in ICP during TOF corrective surgery ventriculo-peritoneal (VP) shunt should be performed before cardiac surgery. We present the first case report of a 11-month-old male baby afflicted with DWM and TOF who underwent successful TOF total corrective surgery and fresh autologous pericardial pulmonary valve conduit implantation under cardiopulmonary bypass after 1 week of VP shunt insertion.

Effect of costimulants on interleukin-2-like activities from goat peripheral blood mononuclear cells.

Culture supernatants containing interleukin-2-like activities (CS-IL2) were prepared from goat peripheral blood cells (mononuclear cells 75% and polymorphonuclear cells 25%). These were stimulated with three costimulants, (tetradecanoyl phorbol acetate, indomethacin and calcium ionophore A23187), either alone or in different combinations, in RPMI-1640 medium (containing 0.5% bovine serum albumin (BSA)) with or without serum. After 18 h of incubation with costimulants, concanavalin A (Con A) was added and the incubation was continued for next 48 h. Higher interleukin-2 (IL-2)-like activities were generated in the culture supernatants prepared in RPMI-1640 growth medium containing 0.5% BSA without serum. Further, IL-2-like activities were much higher in culture supernatants obtained by stimulation with all the three costimulants, as well as Con A, than the two costimulants with Con A or any of the costimulants with Con A.

Balloon mitral commissurotomy: an intraoperative assessment.

OBJECTIVE: Advances in balloon catheter technology have revolutionized the management of obstructive cardiovascular diseases. For lesions like mitral stenosis, balloon commissurotomy has emerged as an alternative to surgical relief showing definite functional benefits in a few clinical trials, albeit with variable results. Such variability necessitated objective evaluation of the efficacy of balloon mitral commissurotomy. METHODS: The balloon mitral commissurotomy was carried out in 11 patients suffering from isolated mitral stenosis, under vision in a surgical setting. All patients were in NYHA class III/IV. Initially single balloon was used for mitral commissurotomy followed by double balloon, before completing the mitral valvotomy with surgical instruments whenever required. The commissural split was measured by firmly stretching the two commissures using nerve hooks and measuring the distance between the two hooks with the help of a caliper. Assessment of balloon dilation was made by calculating exact percentage of residual commissural split following balloon dilation as compared with completed mitral valvotomy. The exact percentage of commissural split was thus obtained by subtracting residual commissural split following balloon dilation from commissural split obtained after surgical open mitral valvotomy. RESULTS: Complete commissurotomy using the balloon technique was possible in two (18.2%) patients. In the remaining nine (81.8%) patients, balloon expansion provided only 50% to 80% of commissural split and required instrumental completion with good results. CONCLUSIONS: Balloon mitral commissurotomy, by virtue of its circumferential force, helps to develop a good cleavage and attains good hemodynamic improvement which may be life saving in critical mitral stenosis in selected group of patients with pliable mitral leaflets and minimal subvalvular pathology.

Interictal SPECT with Tc-99m HMPAO studies in migraine patients.

Migraine is considered to be a functional neurological disorder. For several years cerebral blood flow studies have been fueling the controversy surrounding the pathophysiology of migraine headache. Tc-99m HMPAO SPECT brain imaging was performed during the headache-free period in 44 migraineurs. The findings were compared with those of age 17 and sex-matched controls. The SPECT analysis was performed by using a 360 degrees rotating single head gamma camera system (Toshiba GCA 602A/SA, Japan), equipped with a LEAP collimator, interfaced to a Toshiba computer system, after 20 minutes following the injection of 350-550 MBq of Tc-99m HMPAO. The SPECT images revealed clear interhemispheric asymmetry in the upper frontal and occipital parts of the brain in migraineurs. It is suggested that an impaired regional cerebral vascular autoregulation may exist even during headache-free intervals in patients suffering from migraine.

Cannulation of the internal jugular vein in patients undergoing open heart surgery.

A total of 476 internal jugular vein cannulations performed between June 1990 to August 1991 were prospectively evaluated. The patients' age ranged between ten days to 61 years. We achieved a high success rate of cannulation (97.9%). We describe the use of two single lumen catheters inserted through right internal jugular vein as an alternative to the popular multilumen catheters. We also suggest that low approach should be tried more often in children, if the central approach fails.

Blood conservation in valve surgery.

Blood utilization in 40 patients undergoing elective valve surgery was prospectively studied. The patients had valvular lesions of rheumatic origin with a mean age of 29.1 years and a mean preoperative hematocrit of 35.23 +/- 4.16. Blood was removed from all patients after induction of anesthesia and reinfused after bypass (mean 365.12 +/- 66.96 ml). Membrane oxygenator was used in all the patients. All discard suction was routed through a regionally heparinised collecting and processing system, and the resulting red cell concentrate was transfused. At the conclusion of bypass, all blood remaining in the pump oxygenator was also processed by cell saver and used for subsequent reinfusion. Normovolemic anemia was accepted in hemodynamically stable patients. Thirty two patients (80%) received no bank blood or blood products during their entire hospital course. A total of twelve units of whole blood was transfused into eight patients.

Mechanical ventilation after open heart surgery.

One hundred adult patients, undergoing elective open heart surgery over a period of 4 months, were studied to assess the practice of ventilation in the post operative period. The anaesthetic technique employed used moderate doses of morphine, supplemented with halothane and a muscle relaxant. The decision to extubate was based on clinical assessment, and satisfactory blood gases following a 45 minute T-piece trial. The patients were ventilated for an average duration of 8 hours and 2 minutes and 59 out of 100 patients were extubated within 8 hours. Patients undergoing coronary artery bypass graft were ventilated for significantly longer durations (10 hours 28 minutes) (p < 0.05) and had significantly lower arterial oxygen tension (p < 0.01) 30 minutes after extubation, as compared with those undergoing valvular surgery. Also patients whose bypass time exceeded 2 hours had significantly longer extubation times (p < 0.05) as compared with those who had a bypass time less than 1 hour. T piece trial was found to be a satisfactory method of weaning in all the patients.

Surgical management of cardiac myxomas.

Cardiac myxomas are rare cardiac lesions, though they are the commonest tumours of the heart. Seventeen cases of cardiac myxomas have been operated during the last one decade. Exertional dyspnoea, palpitation and chest pain were the main presenting symptoms. Echocardiographic assessment was the only definitive diagnostic investigation required prior to surgery. Early surgical excision was planned in all the cases. Irrespective of the exposure techniques, removal of the tumour with wide excision of its base was practised. There was one early death due to low cardiac output in a patient brought in a shock like state. Follow up study has revealed 14 patients in NYHA class I and two patients are having class II symptoms. Periodic echocardiographic follow up study has not revealed any recurrence till date. It is concluded that an early diagnosis and surgery gives excellent long term results in these cases.

Control of tachycardia and hypertension following coronary artery bypass graft surgery: efficacy and haemodynamic effects of esmolol.

Hypertension following coronary artery bypass grafting is not uncommon, especially in patients having good left ventricular function. It is often accompanied by tachycardia. The purpose of this study is to determine the efficacy of esmolol in the treatment of tachycardia and hypertension immediately following cardiopulmonary bypass and to study other haemodynamic effects of esmolol. Thirty patients undergoing elective [corrected] coronary artery bypass grafting were included in this prospective study. Morphine-based anaesthetic technique along-with standard bypass techniques were used in all the patients. The study was performed in the operating room about 30-45 minutes after the termination of cardiopulmonary bypass. Patients having a heart rate of more than 90 bpm and systolic blood pressure of more than 130 mm Hg without any inotropic support were included and randomly assigned to esmolol or control group. Esmolol was administered in a bolus dose of 500 micrograms/kg followed by infusion of upto 100 micrograms/kg/min. The patients in the control group were administered comparable volumes of normal saline. Baseline haemodynamic measurements were obtained just before the administration of esmolol or normal saline and were repeated after 5, 10, 15, 30 and 45 min. The baseline measurement in both the groups showed that patients were maintaining a state of hyperdynamic circulation with high systolic blood pressure (esmolol group 148 +/- 15 mm Hg, control group 140 +/- 8 mm Hg; p = NS), heart rate (esmolol group 128 +/- 17 bpm, control group 127 +/- 17 bpm; p = NS) and cardiac index (esmolol group 3.1 +/- 1 L/min/m2, control group 3.3 +/- 0.5 L/min/m2; p = NS). Esmolol decreased systolic blood pressure (p < 0.001), heart rate (p < 0.01) and cardiac index (p < 0.05) at five minutes. These changes persisted throughout the study period. The left ventricular stroke work index decreased at five minutes (p < 0.05) and remained so till 30 minutes. The maximum fall in heart rate (15%) and systolic blood pressure (16%) was observed at 45 minutes. There were no haemodynamic changes in the control group except that cardiac index, stroke volume and left ventricular stroke work index increased at five minutes. We conclude that esmolol lowers the indices of cardiovascular work in patients who demonstrated hyperdynamic circulation. This was achieved by decreasing the heart rate and systolic blood pressure which was accompanied by decrease in cardiac index and left ventricular stroke work index.

Haemodynamic effects of leg raising in patients undergoing coronary artery bypass grafting.

Twenty patients undergoing elective coronary artery bypass grafting were studied prospectively to evaluate the haemodynamic effects of passive leg raising. The patients were divided into two groups: those having good left ventricular function with ejection fraction of 0.50 or more (group I, n = 10) and those having poor left ventricular function with ejection fraction of upto 0.35 (group II, n = 10). Morphine-based anaesthetic technique was used and standard haemodynamic measurements were obtained at following stages: (1) control--20 to 30 min after induction of anaesthesia; (2) one minute, and (3) five min after raising both the legs; (4) one min, and (5) five min after the legs were repositioned. In group I, heart rate decreased from 71 +/- 9 to 66 +/- 8 beats/min (p < 0.001) at stage 1 and persisted throughout the study period. This was accompanied by a decrease in cardiac index, although, the statistical significance was achieved at stage 3 and 4 only. The haemodynamic changes observed in group II were of more severe magnitude. The heart rate decreased from 90 +/- 13 to 84 +/- 13 beats/min at stage 1 (p < 0.05) and persisted throughout the study with maximum decrease of 14 percent occurring at stage 3. The cardiac index decreased significantly from 2.4 +/- 0.3 to 2.0 +/- 0.5 L/min/m2 (p < 0.05) at stage 1. This persisted throughout the study except that it recovered at stage 4. The maximum decrease in cardiac index (20%) occurred at stage 2. In addition, systemic vascular resistance increased significantly from 1458 +/- 255 to 1830 +/- 420 dyne.sec.cm-5 (p < 0.05) at stage 1 and persisted throughout the study period. We conclude that passive leg raising should be undertaken with caution in patients with coronary artery disease especially in those who have poor left ventricular function.

Healed perivalvular abscess: Incidental finding on transesophageal echocardiography [corrected].

A 36-year-old male patient presented with the complaints of palpitations and breathlessness. Preoperative transthoracic echocardiography (TTE) revealed a bicuspid aortic valve; severe aortic regurgitation with dilated left ventricle (LV) and mild LV systolic dysfunction (ejection fraction 50%). He was scheduled to undergo aortic valve replacement. History was not suggestive of infective endocarditis (IE). Preoperative TTE did not demonstrate any aortic perivalvular abscess. Intraoperative transesophageal echocardiography (TEE) examination using the mid-esophageal (ME) long-axis view, showed an abscess cavity affecting the aortic valve, which initially was assumed to be a dissection flap, but later confirmed to be an abscess cavity by color Doppler examination. The ME aortic valve short-axis view showed two abscesses; one was at the junction of the non-coronary and left coronary commissure and the other one above the right coronary cusp. Intraoperatively, these findings were confirmed by the surgeons. The case report demonstrates the superiority of TEE over TTE in diagnosing perivalvular abscesses.

Resumption of ovarian cyclicity and fertility response in bull-exposed postpartum buffaloes.

A study was undertaken to evaluate the effect of bull exposure on resumption of ovarian cyclicity and fertility response in postpartum buffaloes raised under standard farm conditions. A total of 24 Murrah buffaloes was randomly grouped to receive one of the following treatments: (1) exposure to a vasectomised bull from 40th to 90th day postpartum (bull-exposed, BE, n=11) and (2) isolated from bull (non-exposed, NE, n=13). Changes in the progesterone concentration were used to assess the resumption of ovarian cyclicity. Postpartum interval to resumption of ovarian cyclicity (47+/-2.58 days vs. 56+/-2.37 days, p<0.05) as well as behavioral estrus (57+/-3.61 days vs. 71+/-5.13 days, p<0.05) was shorter in bull-exposed animals than control animals. Similarly, animals in the BE group had significantly shorter interval to postpartum ovulation (48+/-2.69 days vs. 57+/-2.37 days, p<0.05). Reduced incidence of silent ovulation was observed in BE group compared to NE group (18.18% vs. 50%). More than half proportion of animals in BE group conceived by 60 days postpartum compared to a very low proportion of animals in NE group (54% vs. 15%, p<0.05). Furthermore, first service conception rate in BE animals was significantly greater than NE animals (100% vs. 37.50%, p<0.05). In conclusion, continuous bull exposure to buffaloes during later postpartum period accelerates resumption of ovarian cyclicity, reduces incidence of silent ovulation and enhances first service conception rate. These results indicate that introduction of bulls to buffalo herd could be a rational management strategy for reducing the postpartum anestrus by enhancing reproductive function in buffaloes.