• Asian-Australasian Journal of Animal Sciences
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• v.10 no.3
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• pp.293-297
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• 1997

Studies were designed to study the peri-parturient rise in strongyle faecal egg counts (FEC) in ewes grazing in a rubber plantation in North Sumatra, Indonesia. In three consecutive lambing seasons strongyle FEC of peri-parturient ewes and dry ewes were monitored from 2 to 3 weeks before lambing until 7 to 9 weeks post lambing to measure the magnitude and duration of the peri-parturient rise. A significant rise in FEC was observed during the post-parturient period in two of the three studies. FEC increased in the three studies from lambing day, and were elevated until 5 to 9 weeks following lambing. Lactating ewes shed on average 3 times more eggs than dry ewes. Lactating ewes were therefore considered as an important source of pasture infection. These findings are discussed in relation to the epidemiology and control of gastrointestinal nematodes in the humid tropics.

• Journal of Animal Science and Technology
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• v.56 no.3
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• pp.8.1-8.6
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• 2014

Background: Artificial insemination (AI) can serve as a powerful tool to the sheep owners for making rapid genetic progress of their flock. The AI in sheep is mostly performed using fresh semen with two reasons i) lambing rate following trans-cervical AI with frozen semen is limited by the inability of frozen-thawed sperm to transit the cervix and ii) the need of circumventing the cervical barrier through laparoscope aided intrauterine AI. Therefore, AI with frozen-thawed semen is not as widespread in sheep as it is in other domestic species. However, to get maximum benefits through the use of AI, frozen-thawed semen is a prerequisite because instead of high fertility, the short shelf life of fresh semen coupled with a limitation on the number of insemination doses achievable per unit time restricts the widespread use of individual sires. Therefore, in order to enhance lambing rate, a total of 240 trans-cervical artificial inseminations with frozen-thawed semen were performed in Bharat Merino ewes during autumn season either once in the evening (G-I, 10 h after onset of estrus, n = 100) or twice (G-II, 14 h and 22 h after onset of estrus, n = 140) i.e. once in the morning and again in the evening. Results: The pregnancy rate (proportion of pregnant ewes confirmed by ultrasonography at day 40) and lambing rate (proportion of ewes lambed) were higher in G-II as compared to G-I (26.4 vs 20% and 19.3 vs 10%, respectively). The difference in lambing rates was statistically (P < 0.05) significant. The depth of insemination within cervico-uterine tract had no significant effect on pregnancy and lambing rates. Conclusions: The results indicate that lambing rate in sheep following TCAI with frozen-thawed semen was significantly influenced by time of inseminations. Two inseminations after 14 and 22 h of onset of estrus enhanced the lambing rates of Bharat Merino sheep as compare to single insemination after 10 h of onset of estrus. The TCAI technique with frozen-thawed ram semen is promising and may serve as a valuable tool for genetic improvement of sheep breeds. Research efforts are going on worldwide to overcome the poor fertility following TCAI with frozen-thawed semen.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.8
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• pp.1119-1126
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• 2013

The objective of this study was to compare the goodness of fit of four lactation curve models: Wood's Gamma model (WD), Wilmink (WL), and Pollott's multiplicative two (POL2) and three parameters (POL3) and to determine the environmental factors affecting the complete lactation curve of F1 dairy sheep under organic management. A total of 5,382 weekly milk yields records from 150 ewes, under organic management were used. Residual mean square (RMS), determination coefficients ($R^2$), and correlation (r) analysis were used as an indicator of goodness of fit for each model. WL model best fitted the lactation curves as indicated by the lower RMS values (0.019), followed by WD (0.023), POL2 (0.025) and POL3 (0.029). The four models provided total milk yield (TMY) estimations that were highly correlated (0.93 to 0.97) with observed TMY (89.9 kg). The four models under estimated peak yield (PY), whereas POL2 and POL3 gave nearer peak time lactation estimations. Ewes lambing in autumn had higher TMY and showed a typical curve shape. Higher TMY were recorded in second and third lambing. Season of lambing, number of lambing and type of lambing had a great influenced over TMY shaping the complete lactation curve of F1 dairy sheep. In general terms WL model showed the best fit to the F1 dairy sheep lactation curve under organic management.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.10
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• pp.1395-1399
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• 2004

The objective of this study was to evaluate the effect of dietary fat inclusion on nutrient intake, body weight, milk production, return to estrus, pregnancy and lambing of winter-lambing, postpartum Awassi ewes. Thirty multiparous, winter-lambing Awassi ewes (body weight=51${\pm}$7.0 kg) were randomly assigned to three dietary treatments (n=10) for 62 days using a completely randomized design. Experimental diets were isonitrogenous, and were formulated to contain 0 (CON), 2.5 (MF), and 5% (HF) added fat, and 33% of the dietary crude protein (CP) as undegradable intake protein (UIP). On day 26 postpartum (day 0=parturition), ewes and their lambs were housed in individual pens for 28 days. Feed offered and refused was recorded daily. At the end of this period, ewes and their lambs within each treatment were combined into one group and fed their respective diet ad libitum. One fertile Awassi ram fitted with a marking harness was allowed with each group for 34 days. No significant (p>0.05) differences in dry matter intake, organic matter intake, and crude protein intake were observed for ewes fed the three experimental diets. No difference was observed in metabolizable energy intake (MEI) for ewes fed the CON and the MF diets (average 8.3 Mcal/d) diet. However, ewes fed the HF diet had greater(p<0.05) MEI compared with the rest of the treatments. Ewe body weights increased throughout the study, unaffected by the experimental diets. No significant differences in milk production were found among ewes fed the three experimental diets. No significant differences were observed in pregnancy rate (6/10, 5/10, 6/10 for CON, MF and HF diets, respectively), lambing rate and the number of lambs per ewe among the three treatments. postpartum reproductive performance of well-fed, winter-lambing Awassi ewes.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.7
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• pp.957-962
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• 2002

In July, three trials were conducted to evaluate the best sponge type and optimum PMSG dose to be administered to sheep under the Jordanian Badia (arid) conditions. In trial 1, three flocks (n=77, n=18 and n=47 for flocks 1, 2 and 3, respectively) were administered with 40 mg fluorogestone acetate (FGA) intravaginal sponges for 12 days before receiving 600 IU of PMSG at the time of sponge removal. In trial 2, 95 ewes were assigned to 4 groups to receive 300 (n=25), 450 (n=27), 600 (n=22) or 750 (n=21) IU of PMSG following a 12 d FGA 40 mg sponge insertion period. In trial 3, 60 ewes were assigned to 3 groups (n=20) to receive either FGA 30 mg, FGA 40 mg or medroxyprogesterone acetate (MAP) 60 mg intravaginal sponges all followed by an administration of 600 IU of PMSG at sponge removal. In all trials, rams were isolated 1 day before sponge insertion and were allowed back with the ewes at sponge removal. Estrual responses and lambing data were collected. The effects of treatment, milking status and face color on estrual responses and lambing data were examined. In trial 1, greater first cycle conception rate (p<0.05), twinning rate (p<0.01) and the number of lambs born/served ewe (p<0.01) were observed in flock 2 compared with flocks 1 and 3. Neither face color nor milking status had any influence on the measured parameters (p>0.05). Despite low lambing rate in trial 2, ewes receiving 600 IU of PMSG had greater (p<0.05) number of lambs born/served ewe compared with ewes receiving 450 IU of PMSG. Regardless of PMSG dose, intervals to detected estrus occurred 10 h earlier (p<0.01) in dry than lactating ewes. Similar to trial 2, lambing rate was depressed in trial 3. The expression of estrus was advanced (p<0.05) in ewes receiving MAP 60 mg sponges compared with those receiving FGA 30 and FGA 40 mg sponges (42$\pm$3.1, 49$\pm$3.1 and 49$\pm$3.1 h post sponge removal in ewes receiving MAP 60 mg, FGA 30 mg and FGA 40 mg sponges, respectively). Other parameters were not influenced (p>0.05) by sponge type, milking status and face color. Data show that a 600 IU dose of PMSG tends to give the best lambing results. In addition, results indicate that the use 60 mg MAP sponges for estrus synchronization may be more appropriate under the Jordanian Badia conditions during late seasonal anestrus.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.1
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• pp.36-42
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• 2013

The average twin lambing rate of Bayanbulak sheep is 2% to 3%. However, a flock of sheep with a close genetic relationship and an average of 2 to 3 lambs per birth has been found recently. To determine the major genes controlling the prolificacy of the flock in the present study, the flock was designated A while 100 normal Bayanbulak sheep were randomly selected to comprise the control flock B. Ligase detection reaction method was applied to detect and analyze the 10 mutational loci of the 3 candidate prolificacy genes including bone morphogenetic protein type I receptors, bone morphogenetic protein 15, and growth differentiation factor 9. The 10 mutational loci are as follows: FecB locus of the BMPR-IB gene; $FecX^I$, $FecX^B$, $FecX^L$, $FecX^H$, $FecX^G$, and $FecX^R$ of the BMP15 gene; and G1, G8, and FecTT of the GDF9 gene. Two mutations including BMPR-IB/FecB and GDF9/G1 were found in Bayanbulak sheep. Independence test results of the two flocks demonstrate that the FecB locus has a significant effect on the lambing number of Bayanbulak sheep. However, the mutation frequency of the G1 locus in GDF9 is very low. Independence test results demonstrate that the GDF9 locus does not have a significant impact on the lambing performance of Bayanbulak sheep. Among the 10 detected loci, BMPR-IB/FecB is the major gene that influences the high lambing rate of Bayanbulak sheep.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.6
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• pp.737-742
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• 2004

Garole, a prolific small sized sheep breed of West Bengal, was introduced in the Mutton project of the Institute in 1997 to explore the possibility of incorporating fecundity gene(s) into monotocus Malpura sheep of Rajasthan. Results of reproduction and production traits in respect of Garole${\times}$Malpura (G${\times}$M) half-breds have been obtained. Of 35 lambing obtained so far from the ewes of Garole${\times}$Malpura, 45.71% were twin lambing, whereas, Malpura sheep produced mostly single lamb except 2.55% twin lambing on an average. Other reproduction traits in G${\times}$M ewes such as lambing rate, litter size at birth and weaning were considerably improved over Malpura ewes. Results revealed that the fecundity genes responsible for increasing ovulation rate and litter size have been incorporated in to the G${\times}$M genotype and it might prove a valuable germ plasm towards evolving a new prolific strain of sheep. Interestingly, survivability of G${\times}$M half-breds was almost at par with the local Malpura sheep in harsh climatic conditions of semi-arid tropics. The body weights at different ages of G${\times}$M half-breds were on little lower side compared to contemporary Malpura lambs. Average kilogram of lambs weaned/ewe lambed in Malpura and G${\times}$M genetic group was 11.86 and 11.07 kg respectively. In view of minimizing the differences in body weights and kg of lambs weaned/ewe lambed between the two genetic groups, G${\times}$M ewes has to be backcrossed with Malpura rams to raise the inheritance of latter up to 75% level. However, further research is needed to reach on certain conclusions regarding net returns from such crosses.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.5
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• pp.633-636
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• 2002

Six adult Garole rams maintained under a semi-intensive system were used as semen donors for this study. Semen was collectied daily during the monsoon season with the help of an artificial vagina and examined for its quality characteristics. Ejaculates of thick consistency, rapid wave motion, ${\geq}80%$ motility and intense movement of motile spermatozoa were diluted at the rate of 1:1 with egg yolk McIllvaine glucose diluent at $30^{\circ}C$ in water bath. Estrus in ewes was detected by parading aproned rams of proven vigour at 12 h intervals. The ewes (54 Malpura and 23 Avikalin) in estrus were artificially inseminated with fresh diluted ram semen. The overall conception rate was 94.8%, (range 91.7 to 100%). The overall lambing percent was 80.5 with a range of 75.0 to 84.6%. There was no significant (p>0.05) difference in lambing and conception rate because of individual rams. Fertility was significantly lower (p<0.05) in ewes of less than two years and more than six years of age. Breed (Malpura and Avikalin) effect was not observed in conception and lambing rate (p>0.05). No significant difference (p>0.05) in birth weight and 12 month weight was observed between Garole${\times}$Avikalin and Garole${\times}$Malpura crossbred lambs but there was significant (p<0.05) difference at three month and six months body weight of both the crossbred lambs.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.3
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• pp.308-311
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• 2010

An experiment was conducted using indigenous Kivircik ewes to evaluate the effect of intravaginal progestagen sponges, containing 30 mg of fluorogestone acetate (FGA), followed by administration of pregnant mare serum gonadotrophin (PMSG) on inducing synchronized oestrus in the season and fertility. Three times of PMSG administration relative to sponge withdrawal (24 h before (n = 30), at (n = 29) or 24 h after (n= 29)) and two routes of PMSG administration (intramuscular (n = 46) and subcutaneous (n = 42) were compared for estrous response, number of multiple births and fecundity rates. There were no significant differences in terms of estrous response, due to differences in the time and route of PMSG administration. Lambing percentage, proportion of multiple births and fecundity were 75.6, 51.6 and 114.6%, respectively. The administration had a significant effect on lambing (p<0.05), multiple birth and fecundity rates (p<0.01). The subcutaneous administration of PMSG resulted in a significantly higher lambing rate (p<0.05) and fecundity rate (p<0.01), compared to the intramuscular injection of the PMSG.

• Journal of Animal Reproduction and Biotechnology
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• v.35 no.2
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• pp.190-197
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• 2020

The effects of the number of frozen-thawed ram sperm per single and double intra-cervical artificial insemination (AI) on fertility in ewes were studied. A total of 89 non-pregnant ewes were synchronized for oestrus with two doses of 100 ㎍ PGF_2α (Cloprostenol) 9 days apart. The ewes were randomly assigned to one of four groups; D200 (n = 23; double AI with 200 × 10⁶ sperm), S200 (n = 24; single AI with 200 × 10⁶ sperm), D100 (n = 24; double AI with 100 × 10⁶ sperm) and S100 (n = 18; single AI with 100 × 10⁶ sperm). Ewes were inseminated within 12 to 18 h for single AI and, within 10 to 12 h and 16 to 18 h for double AI after the onset of oestrus. The onset of oestrus ranged from 28 to 76 h (54.33 ± 1.28 h). The high percentage (29.2%) of ewes showed oestrus between 51 to 60 h. The non-return rates were highest in group D200 (56.5%) and differed significantly (p < 0.05) from group S100 (11.1%). No ewes were pregnant in group S100, and the pregnancy rates among the remaining groups did not differ. The mean gestation period was 152.8 ± 0.5 days and no difference was observed among the groups. The lambing and multiple birth rates were 100% in group D200. The single and twin lambing was highest in group D100 (33.3%) and group D200 (83.3%), respectively. Only one triplet lambing and the highest lambing size (2.2 ± 0.2) was recorded in group D200. In conclusion, double AI with 200 × 10⁶ sperm showed comparatively most practical for achieving high pregnancy rates and lambing performances in Bangladeshi ewes under field conditions.