A novel action of insulin sensitizing drug as a potential promotor of preovulatory follicles, ovulation rate and prolificacy in sheep.

The effect of the insulin-sensitizing drug metformin on preovulatory follicle (POF) number, ovulation rate, fetal rate and prolificacy was studied in forty-six cyclic Malpura ewes. After estrus synchronization, the ewes were equally divided into two groups (n = 23). The treatment group (MET) received a daily oral dose of metformin at a rate of 500 mg/animal for approximately 12 weeks, spanning five estrous cycles, as against untreated control (CON). All the ewes were bred to proven rams at the end of treatment. Ovarian ultrasound scans were performed at each estrus and day 9 of each cycle to assess the number and diameter of POFs and corpora lutea (CL), respectively. A comprehensive assessment of circulating hormones including, estradiol, progesterone, androstenedione, and insulin as well as metabolic indicators such as glucose, and lipid profile parameters was performed. At the end of treatment on the day of estrus (E5D0), the treatment showed a stimulatory effect on follicular development with a 53.2% (P < 0.001) increase in the number of POFs. It also increased the ovulation rate by 67.4% (P < 0.01), with a higher proportion (χ2df1 = 10.7, P < 0.001) of ewes in the MET group having multiple ovulations compared to the CON group (82.6 vs. 30.4%). With 1.48 ± 0.12 prolificacy rate in MET ewes, the proportion of ewes giving birth to multiple lambs was 2.9-fold higher than in the CON group. Plasma estradiol, insulin, glucose, total cholesterol, and LDL-cholesterol concentrations were lower (P < 0.05) in the MET ewes than in the CON. The results of the present study indicate that metformin can increase the number of POF, ovulation rate, fetal rate and prolificacy in ewes, while reducing the plasma estradiol, insulin, glucose and cholesterol in MET ewes.

Supplementation of Moringa oleifera leaf concentrate pellets on nutrient utilization, antioxidant status, and reproductive performance of prolific ewes during extreme summer months in semi-arid tropical conditions.

A feeding trial was conducted for a period of 60 days during extreme summer months to observe the effect of supplementation of Moringa oleifera leaves containing concentrate pellets on nutrient utilization, antioxidant status, and reproductive performance in Avishaan ewes reared under semi-arid condition. Forty adult non-pregnant cyclic ewes (2-3 years, 31.8 ± 0.81 kg body weight) were selected and randomly allocated into 2 groups of 20 animals each, viz., G-I (control) and G-II (treatment). The ewes were grazed on natural pasture for 8 h, offered ad libitum Cenchrus ciliaris hay after grazing and concentrate pellets @ 300 g/animal/day. The ewes in G-I were offered conventional concentrate pellets, whereas G-II ewes were offered concentrate pellets containing 15% Moringa leaves. The mean temperature humidity index during the period of study was 27.5 ± 0.3 and 34.6 ± 0.4 at 0700 h and 1400 h, respectively, indicating severe heat stress. Nutrient intake and utilization were comparable between the two groups. The antioxidant status was higher in G-II ewes as the values of catalase, superoxide dismutase, and total antioxidant capacity were higher (P < 0.05) in G-II ewes compared to G-I. The conception rate was higher (100%) in G-II ewes than G-I ewes (70%). Multiple birth percentage was 77.8% in G-II ewes, and it was comparable with the herd average of Avishaan (74.7%). However, ewes in G-I group exhibited a marked decline in multiple birth percentage (28.6%) than the normal herd average. Hence, it can be concluded that inclusion of Moringa oleifera leaves in feeding of prolific Avishaan ewes improved their antioxidant status resulting in optimum reproductive performance during stressful summer months.

Dietary n-3 PUFA augments pre-ovulatory follicle turnover and prolificacy in well-fed ewes.

The present study evaluated the effect of dietary supplementation with n-3 polyunsaturated fatty acids (PUFA) on preovulatory follicle (POF) turnover, prolificacy, and endocrine and metabolic milieu in Malpura sheep. Fifty cyclic ewes with 3-3.5 body condition scores on a five-point scale were allocated equally to two groups (n = 25) following estrus synchronization and were supplemented with 0.6 mL/kg body weight of n-3 PUFA-rich fish oil (FO) or palm oil (PO) as control, for 60 d following an acclimatization period of 7 d. All ewes were mated with sexually active rams at the end of the supplementation period. On ultrasonographic ovarian scanning at the last fourth estrus, the mean number of POFs was 77.8% greater (P < 0.01) in FO ewes than in the PO ewes. The proportion of ewes with multiple ovulations two months after the beginning of supplementation was 56% in the FO group as compared to 8% in the PO group. The number of fetuses was 46% higher (P < 0.01) in the FO than in the PO ewes at d 45 of gestation. At lambing, the twinning percent in the FO ewes was three times greater than in the PO ewes (27.3 vs. 9.1%). Plasma cholesterol, estradiol, and insulin concentrations were lower (P < 0.01) in ewes fed with FO than those offered PO group at the end of the feeding period. It was concluded that the dietary supplementation of n-3 PUFA-rich FO in well-fed Malpura ewes improved the number of follicles and ovulation rate which led to an increased prolificacy, accompanied by a reduction of plasma cholesterols, estradiol, and insulin.

Cryostress induces fragmentation and alters the abundance of sperm transcripts associated with fertilizing competence and reproductive processes in buffalo.

The study aimed to assess the influence of cryostress on RNA integrity and functional significance in sperm fertilizing ability. The fresh and post-thawed buffalo sperm (n = 6 each) samples were evaluated for their functional attributes, and sperm total RNA was subjected to transcriptome sequencing followed by validation using real-time PCR and dot blot. Overall, 6911 genes had an expression of FPKM > 1, and among these 431 genes were abundantly expressed (FPKM > 20) in buffalo sperm. These abundantly expressed genes regulate reproductive functions such as sperm motility (TEKT2, SPEM1, and PRM3, FDR = 1.10E-08), fertilization (EQTN, PLCZ1, and SPESP1, FDR = 7.25E-06) and the developmental process involved in reproduction (SPACA1, TNP1, and YBX2, FDR = 7.21E-06). Cryopreservation significantly (p < 0.05) affected the structural and functional membrane integrities of sperm. The expression levels of transcripts that regulate the metabolic activities and fertility-related functions were compromised during cryopreservation. Interestingly, cryostress induces the expression of genes involved (p < 0.05) in chemokine signaling (CX3CL1, CCL20, and CXCR4), G-protein coupled receptor binding (ADRB1, EDN1, and BRS3), translation (RPS28, MRPL28, and RPL18A), oxidative phosphorylation (ND1, ND2, and COX2), response to reactive oxygen species (GLRX2, HYAL2, and EDN1), and immune responses (CX3CL1, CCL26, and TBXA2R). These precociously expressed genes during cryopreservation alter the signaling mechanisms that govern sperm functional competence and can impact fertilization and early embryonic development.

Shielding effect of melatonin improves seminal quality and oxidative stress indices during chilled storage of ram semen.

Supplementation of antioxidant to semen extender maintains seminal quality by reducing oxidative stress during preservation time period. The main aim of this study was to investigate the effect of different concentrations of melatonin supplementation on liquid storage of Magra ram semen. This study was performed on adult Magra ram (n = 8), and seminal ejaculates (48) were collected and evaluated for various macroscopic and microscopic seminal quality parameters for further processing. After preliminary evaluation, ejaculates of each collection session were mixed and divided into four equal aliquots. All the aliquots were diluted (1:10) with Tris-citric fructose egg yolk extender contained sans melatonin served as control, whereas the other three aliquots were supplemented with 0.5, 1 and 2 mM MLT which were grouped as MLT0.5, MLT1 and MLT2, respectively. Thereafter, the samples were stored at 4 ºC for 72 h, and various seminal parameters (individual sperm progressive motility, viability, abnormalities, plasma membrane functionality) along with oxidative stress parameters (total antioxidant capacity (TAC), malondialdehyde (MDA)) were evaluated at 0, 24, 48 and 72 h of preservation. The results indicated that the mean percent values for progressive sperm motility, viability, plasma membrane functionality and TAC were significantly higher (p < 0.05) in treated groups with the highest values in MLT1 group. Significantly lower (p < 0.05) percentage of total sperm abnormalities and MDA level was observed in treatment groups compared to control group. The results report that supplementation of 1 mM melatonin efficiently maintains the seminal quality and ameliorates oxidative stress during preservation at 4 ºC to 72 h.

Effect of dietary n-3 polyunsaturated fatty acid supplementation on the expression of genes involved in progesterone biosynthesis in the corpus luteum of goat (Capra hircus).

Emerging evidence indicates that dietary n-3 polyunsaturated fatty acids (PUFA) alter the fatty acid composition of corpus luteum (CL) and directly affect the luteal function in the cow, which is independent of the inhibitory effect on the endometrial PGF2α production. The present study, thus, investigated the effects of n-3 PUFA rich fish oil (FO) supplementation on the transcriptional modulation of genes involved in the biosynthesis of progesterone (P4 ) in the CL collected during the luteolytic phase of oestrous cycle in the goat. On the day of synchronized oestrus, goats (n = 6/group) were fed an isocaloric diet supplemented with either FO or palm oil (PO). The dose of oil supplementation was 0.6 mlkg-1 body weight, and the duration was 55-57 days. The FO provided 156 mgkg-1 body weight of n-3 eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The CL was collected by laparotomy on day 16 post-oestrus, and the relative abundance of P450 side-chain cleaving enzyme, steroid acute regulatory protein (StAR) and 3ß-hydroxy steroid dehydrogenase (3ß-HSD) genes was quantitated by real-time PCR. The results indicated that the dietary FO significantly upregulated the expression of 3ß-HSD by 1.13-fold and downregulated StAR by ~2-fold as compared to PO group (p < .05). It is concluded that dietary FO differently affected the expression of genes involved in P4 synthesis in the CL during the luteolytic window of the oestrous cycle in the goat.

Effect of n-3 PUFA-rich fish oil supplementation during late gestation on kidding, uterine involution and resumption of follicular activity in goat.

We have shown that dietary supplementation of n-3 polyunsaturated fatty acid (n-3 PUFA)-rich fish oil (FO) around the breeding time improved the utero-ovarian functions in the goat. Here, we investigated the effect of FO supplementation during the periparturient period on serum n-3 PUFA, prostaglandin F2α metabolite (PGFM), placental expulsion, uterine involution, resumption of oestrus and neonatal vigour. Rohilkhandi goat in advanced gestation (n = 16) was divided into two equal groups. One group was supplemented with FO containing 26% n-3 long-chain PUFA at the rate of 156 mg per kg body weight, while the control group was fed isocaloric palm oil (PO) from -3 to +3 week of kidding. Dietary FO increased serum concentration of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) by 7.3- and 6.6-fold, respectively, after 6 weeks of supplementation. Goats in FO group expelled the foetal membranes 99.1 min earlier (p < .01) than those of PO group. Further, dietary FO significantly decreased the serum PGFM on day 7 post-partum. However, no difference was found on uterine involution, which was complete by day 20 post-partum in either group. Resumption of follicular activity by day 5 post-partum was 87.5% in the FO as compared to 25% in the PO group (p < .05). Similarly, occurrence of behavioural oestrus by day 90 post-partum was 57.1% in goats of the FO group while none of does was in the PO group (p < .01) expressed oestrus. It was concluded that feeding FO-rich diet during -3 to +3 weeks of kidding decreased the PGFM till day 7 post-partum, hastened the expulsion of foetal membranes and reduced the time from kidding to first post-partum oestrus in Rohilkhandi does.

Effect of different levels of n-3 polyunsaturated fatty acids rich fish oil supplementation on the ovarian and endometrial functions in the goat (Capra hircus).

Decreasing the ratio of n-6 to n-3 polyunsaturated fatty acid (PUFA) through dietary manipulation improves the reproductive functions in the dairy cow. This study was conducted to determine the effect of dietary supplementation of n-3 PUFA rich fish oil that provided different levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) to determine the optimum dose with respect to endometrial and ovarian functions in the doe. Normal cyclic goats (n = 20) were divided into four groups (n = 5/group) and the fish oil was supplemented for 55 days such that EPA and DHA content were 0, 72, 156 and 312 mg/Kg body weight for CON, LOW, MED and HIGH groups, respectively. The diet was made isonitrogenous and isocaloric. Estrus was synchronized by two PG regimen at 11 days apart with first PG on day 25 of supplementation. Experimental does were observed from second PG till day 17 post-estrus. Ovarian ultrasound revealed that the follicular attributes were comparable among the groups; however, the diameter of CL on day 5 post-estrus was significantly larger in the MED group. Fish oil supplementation even at the lowest dose significantly decreased the serum estradiol (E2) and basal as well as oxytocin (OXT) induced PGFM during the late luteal phase of the estrous cycle (P < 0.05). Further, the MED group showed a significant decrease in the serum E2 on day 17 post-estrus as compared to LOW group. A significant increase in the progesterone (P4) on day 14 post-estrus was recorded in the MED group. Neither the effect of treatment nor time was significant either on day 16 or 17 post-estrus with respect to PGEM following OXT challenge (P > 0.05). It is concluded that the dietary fish oil inhibited OXT induced PGF2α release and decreased E2 during the late luteal phase of the estrous cycle in the doe, which will have a favourable effect on the maternal recognition of pregnancy. In addition, MED level (156 mg/Kg body weight) increased the CL size and circulating P4 during the luteal phase.

Effect of dietary n-3 polyunsaturated fatty acid rich fish oil on the endometrial prostaglandin production in the doe (Capra hircus).

Recently, we showed that dietary supplementation of n-3 PUFA rich fish oil (FO) decreased the metabolites of serum prostaglandin (PG) F2α and E2 during the window of pregnancy recognition in the doe. In this study, we investigated its effect on the changes on endometrial PG production in vitro. Cycling does (n = 12) of Rohilkhand region were divided into two equal groups and fed a concentrate diet supplemented with either FO containing 26% n-3 PUFA (TRT; n = 6) or palm oil (CON; n = 6) @ 0.6 mL/kg body weight for 57 days. Estrus was synchronized by two injections of PGF2α analogue viz, on day 25 and 36 of supplementation and laparo-hysterotomy was performed to obtain endometrial tissue on day 16 of the synchronized estrus. Endometrial explant culture was done using a defined medium.The basal PG production was assayed at 6 and 12 h. Endometrial explant was stimulated with oxytocin (OXT) and/or recombinant ovine interferon tau (roIFN-τ) and PGs were assayed at 3 and 12 h post-treatment. The relative expression of genes related to PG metabolism in the endometrium was done by Quantitative Real Time PCR technique (qRT-PCR). There was a significant (P < 0.05) decline in the basal production of PGF2α and PGE2 in the TRT as compared to the CON group. The cultured endometrial tissue produced PGF2α in a time- dependent fashion in both the groups (P < 0.05). Neither OXT nor roIFN-τ had a significant (P > 0.05) effect on the PGF2α and PGE2 production in the TRT group. Similarly, the PG production in the OXT and roIFN-τ was comparable with the control in TRT. Expression of mRNA for cyclooxygenase-2 (COX-2), cytosolic phospholipase A2 (cPLA2) and PGF synthase (PGFS) was lower (P < 0.05) whereas, PGE synthase and peroxisome proliferator-activated receptors such as PPAR-γ and δ was increased (P < 0.05) in n-3 PUFA fed doe. In conclusion, dietary supplementation of FO decreased the endometrial production of PGF2α and PGE2 by downregulating the COX-2, cPLA2 and PGFS transcripts in the doe. The findings suggest that n-3 PUFA influence embryo survival by modulating the endometrial PG.

Supplementation of vitamin E, selenium and increased energy allowance mitigates the transition stress and improves postpartum reproductive performance in the crossbred cow.

Dairy cow undergoes tremendous physiological challenges during the transition period leading to negative energy balance (NEBAL), impaired immunity and oxidative stress that ultimately compromises the postpartum fertility. Accordingly, we investigated the effects of antioxidant supplementation and increased energy allowance on transition stress and fertility of crossbred cow. Advanced pregnant crossbred cows (n = 26) of 2-4 parity and lactation potential of >10 L/day were divided into two equal groups (n = 13 cows/group). Cows were fed diets either (i) supplemented with vitamin E (80 IU/kg DM), Selenium (Se; 0.3 mg/kg DM) and increased energy allowance in the form of 20% additional concentrate (TRT) or (ii) basal diet without any supplementation as control (CON). Vitamin E and Se were supplemented with wheat flour bolus from -4 to 8 week of calving whereas energy allowance was increased from 2 to 8 week of calving on daily basis to individual animal (where 0 is day of calving). Blood samples were collected on weekly interval from -4 to 8 week of calving. Oxidative stress was assessed by estimation of malondialdehyde (MDA), total antioxidant capacity (TAC), superoxide dismutase (SOD) and catalase (CAT). Immunity level was assessed via estimation of phagocytic activity (PA) of granulocytes and lymphocyte proliferation assay (LPA). Postpartum fertility was assessed by interval to first postpartum estrus (day) and pregnancy rate. Cows in TRT had a significantly lower MDA, higher TAC and decreased activity of SOD and CAT than that of CON (P < 0.05). Phagocytic activity increased at -1, 0 and 3-8 weeks postpartum (P < 0.05) while LPA showed difference (P < 0.05) at parturition, week 4 and 8 postpartum. Marked improvement in the fertility was recorded in terms of early resumption of postpartum estrus (P < 0.001) and higher pregnancy rate (P < 0.05).

Effect of dietary supplementation of omega-3 polyunsaturated fatty acid (PUFA) rich fish oil on reproductive performance of the goat (Capra hircus).

Dietary supplementation of n-3 PUFA decreases the luteolytic PGF2α and improves the pregnancy rate in the dairy cow. However, its effect in the goat is not known. Accordingly, we studied the effect of supplementation of n-3 PUFA rich Fish oil (FO) on different reproductive events in the goat. Cycling goats (n = 30) were divided into two equal groups and fed an isocaloric and isonitrogenous diet supplemented with either FO (TRT; n = 15) or palm oil (PO) (CON; n = 15) @ 0.6 mL/kg body weight for 72 days during the breeding season. Estrus synchronization was done on day 25 and 36 of supplementation using two PG regimen and the goats in estrus were bred. Mean interval from PGF2α administration to the onset of estrus was 12 h longer (P < 0.05) in the TRT group than that of CON. The number of preovulatory follicles (POF) and ovulation rate was significantly higher in FO supplemented goats (P < 0.05) by 39.64 and 41.35%, respectively. Though the corpus luteum diameter was significantly higher (P < 0.05) on day 5, 8 and 11 post-breeding in the TRT group, mean serum progesterone (P4) did not differ significantly (P > 0.05). Mean concentration of serum estradiol (E2) was significantly (P < 0.01) lower in the FO supplemented group during day 0-60 post-breeding which could be due to significantly low serum cholesterol (P < 0.01). Though the serum concentration of PGF2α metabolite (PGFM) and PGE2 metabolite (PGEM) in the pregnant goats was significantly (P < 0.05) lower in the TRT group on day 16 and 17 post-breeding, the ratio of PGEM to PGFM remained unaffected suggesting a favourable effect of FO supplementation on the early pregnancy. The number of embryos, twinning rate and kidding rate were high in FO supplemented group though it was non-significant. However, gestation length, birth weight of kids and neonatal behaviour were comparable between the groups (P > 0.05). In conclusion, supplementation of n-3 PUFA rich FO significantly increased the number of POF and ovulation rate with numerical increase in the kidding rate. Further, it decreased the serum E2 and PGFM during the critical window of pregnancy recognition in the doe.