INTRODUCTION The ultimate goal of dairy management is to remove all those impediments which are coming across the way to achieve the better performance of the animals. Gastrointestinal parasitism is one of the major impediment in achieving optimum performance of animals. Helminths which are a diverse group of parasitic worms, encompassing Nematodes, Cestodes and Trematodes are recognized as a major constraint to livestock production throughout the tropics and elsewhere (Waller, 1997). These infections cause considerable economic loss in terms of productivity in many ways including mortality in heavily parasitized animals (Rinaldi et al., 2011; Wadhwa et al., 2011). The economic losses with parasitism in cattle are mostly associated with subclinical parasitism, with no obvious signs of parasitism but significant losses in potential production. These losses are often very insidious in nature and often difficult to prove statistically in a consistent manner (Hawkins, 1993). Helminthic infections were once reported to be responsible for causing nearly one-third of total losses due to all animal diseases (Anon, 1990). It has also been established that a strategic anthelmintic treatment can improve animals performance including reproductive performance (Stuedemann et al., 1989). To deal with this problem of gastrointestinal parasitism, when it comes to treatment, either they are commonly overlooked as majority of the infected animals show little obvious clinical signs and their effects are gradual and chronic (Raza et al., 2010), thus not drawing the immediate attention of the farmer, or treated conventionally with commercially available chemical anthelmentics. livestock producers are sometimes hesitant to use these anthelmintics due to their associated adverse effect and cost. Another associated issue is emergence of anthelmintic resistance which is a threat to agricultural incomes, and has been reported from all the four corners of the world, to all available drugs, in all classes of helminthes (Lalchhandama, 2010). Emergence of anthelmintic resistance along with associated adverse effects and the high cost of synthetic anthelmintics makes it need of the hour to develop alternative approaches. Herbal based anthelmintics could be the best possible alternative of these synthetic anthelmintics, as plants has long been used for ages by farmers and traditional healers to treat parasitism and to improve performance of livestock. Regardless of their wide ethnoveterinary usage scientific evidence on the anti-parasitic efficacy of most plant products is limited. Many in vitro studies have been conducted to demonstrate the anthelmintic efficacy of different herbs, some of them reported Neem and Garlic as the most efficacious for in vitro anthelmintic activity (Amin et al., 2009). For practical utilization their in vivo validation needs to be done. With these considerations the present study was carried out to evaluate the in vivo efficacy of Garlic and Neem combination for their anthelmintic potential and also its effect on animal’s reproductive performance. MATERIALS AND METHODS The present study was carried out at Livestock Research Centre (LRC), National Dairy Research Institute (NDRI), Karnal, India. Neem leaf powder was procured from local market after assessing their quality in consultation with ayurvedic practitioner and drug manufacturer. Garlic bulbs were purchased from the local market and were dried under the shade for a period of 15 days. After drying, the outer husks were removed and the bulbs were ground to fine powder by using electrical mixer. The herbal mixture was prepared after mixing pulverized herbs in specific proportion. The dose was calculated for the respective animal based on their body weight, then Garlic and Neem powder were weighed accordingly in the ratio of 1:5 (based on the dose rate obtained by the in vitro standardization). Twenty eight freshly calved crossbred Karan Fries (Tharparkar × Holstein Friesian) cows, in first to third parity were selected and none of them had been dewormed at least six month before the start of the experiment. Animals were randomly divided into four (4) groups. Animals in control group (T1) were provided with the routine feeding practices of the farm without any kind of deworming. Animals in treatment groups were fed the same ration as in control group but provided with dewormer as follows- In T2 group: The synthetic dewormer used was Macfen-plusTM. In T3 group: Garlic + Neem in the ratio 1:5 was given @ 4g/kg body weight as single dose on day 7 after parturition. In T4 group: Garlic + Neem in the ratio 1:5 was given @ 4g/kg body weight as single dose on day 7 after parturition and subsequently same dose was repeated on day 60. For in vivo efficacy of the herb, fecal evaluation was done for parasitic eggs. Faecal egg count reduction was calculated as per equation of Coles et al. (1992). To see the effect of herbal anthelmintic on reproductive traits of KF cows, the reproductive parameters were recorded for each cow. For calculating days to first observed estrus, groups of cows were observed twice daily in the morning and evening to determine the signs of estrus by the experienced and skilled personnel and estrus chart was prepared for each cow. Service period was calculated by counting the number of days from calving to the service that resulted in pregnancy and this was confirmed by pregnancy diagnosis after 45-60 days of last service. The numbers of service required for successful conception is called as Number of service per conception were recorded. Conception rate is the proportion of cows that were detected in oestrus and inseminated to that were pregnant. It was calculated as per the following equation. RESULTS AND DISCUSSION A. Effect of herbal anthelmintic (Garlic + Neem) on nematode control (Fecal egg count) In all the anthelmintic treated groups, mean EPG values were found significantly (p≤0.05) lower compared to the control group. In synthetic dewormer group T2 there was observed the highest reduction of 96.79±2.09 % which was significantly higher than the herbal treated groups T3 (57.36±11.44%) and T4 (60.24±7.21 %). The overall mean values of FECR also shows an increase (-14.06±3.34%) in the egg count in the control group, whereas decrease in egg count was observed in all the anthelmintic treated groups. The synthetic dewormer treated group (T2) and the double dose herbal treated group (T4) did not show significant difference (83.20±2.76% and 78.85±3.09 %) in the overall FECR which was significantly better than the single dose (T3) group (56.62±3.39%). B. Effect of herbal anthelmintic (Garlic + Neem) on reproduction performance of cows The data (Table 1) on reproduction performance for different groups were recorded and evaluated on the basis of days to first observed estrous, days to first service, service period, service per conception and first service conception rate. The first observed estrous (DFOE) in T1 was 78.00±4.88 days and for T2, T3 and T4 were 60.71±9.25, 75.14±8.36 and 59.14±3.01days, respectively. For first observed estrous there was found no significant difference between T1 and T3. The treatment group T4 was found to have significantly (p≤0.05) lower interval to first observed estrous, however the group T3 did not found significantly different from either of the groups. The comparatively early postpartum estrous could be due to better energy status of cows in anthemintc treated groups. Resumption of ovarian cyclicity after parturition depends upon nutritional status, body energy reserves and blood glucose level of the animal. As blood glucose is the main source of energy for ovarian function (Rabiee et al., 1997) and influences in vitro bovine thecal steroidogenesis (Stewart et al., 1995), it might have played a major role in achieving early postpartum ovulation. Average number of days to first service (DFS) were found highest in the untreated group. In comparision to untreated cows, T2 and T4 treatment group cows received service 17 and 20.86 days earlier. Service period (SP) was found significantly lower in T2 and T4 groups compared to the untreated group. In comparison to control, cows in T2 and T4 group conceived 28.43 and 34.57 days earlier. The higher service period in control group might be due to higher incidence of negative energy balance and subclinical mastitis. Our findings are supported by Gunay and Gunay (2008). They reported that cow suffering with mastitis prior to first postpartum AI and between first postpartum AI and pregnancy diagnosis had significantly (p≤0.05) extended duration of days open. Conception to first service (FSCR) was found highest in T4 group (57.14%) followed by T2 and T3 groups (42.86%) which was 28.57% in control group. A direct relationship between postpartum energy balance and first ovulation was demonstrated by Canfield et al. (1990). Negative energy balance results into increased BUN concentration (Dhaliwal, 2001). Greater serum or plasma urea nitrogen concentration reduces LH binding to ovarian receptors, leading to decrease in serum progesterone concentration and pregnancy rates (Sharma et al., 2006). Number of services per conception (NSPC) was found lower in cows of herbal anthelmintic treatment group, although non significantly. This suggest the favourable action of herbal antelmintic in improving conception rate with minimum services, which might be due to better status of uterine health which further attributed to anti-oxidant and immune-modulatory action of herbs which prevent infections (Ao et al., 2011; Huang et al., 2010). Similar type of findings on reproductive performance improvement with herbal supplementation has been reported by Cui et al., (2014) in Holstein cows. Chandra (2015) reported that the polyherbal mixture reduced the service period around sixty days in Murrah buffalo. Stuedemann et al. (1989) reported higher pregnancy rates for anthelmintic treated (98%) animals than that for untreated animals (75%). Also, they reported that the calving rate was higher for anthelmintic treated cows (90%) than for untreated cows (68%).