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D. J. Patterson - One of the best experts on this subject based on the ideXlab platform.

  • Altering duration of the preSynchronization period in a long-term progestin-based Estrus Synchronization protocol for timed artificial insemination of beef heifers
    Theriogenology, 2019
    Co-Authors: E Knickmeyer, R.c. Bonacker, Jordan M Thomas, Jaclyn N Ketchum, J.w.c. Locke, Mark R. Ellersieck, Scott E. Poock, Michael F. Smith, Lauren A Ciernia, D. J. Patterson
    Abstract:

    Abstract An experiment was designed to evaluate the effect of extending duration of the preSynchronization treatment in a long-term progestin-based Estrus Synchronization protocol. Heifers were assigned to either an 18 d (Day 0–18) or 14 d (Day 4 to Day 18) CIDR® treatment (1.38 g progesterone controlled internal drug release insert; Zoetis, Madison, NJ), with prostaglandin F2α (PG; 250 μg im cloprostenol sodium) administered 16 d after CIDR® removal (Day 34). Heifers at two locations (location one, n = 193; location two, n = 649) were assigned to treatment based on reproductive tract score (RTS; Scale 1–5) and body weight. Heifers that were assigned RTS 1 were not retained for the trial (n = 6). Estrus detection aids (Estrotect®) were applied at PG. Split-time artificial insemination (STAI) was utilized and AI performed based on expression of Estrus at 66 h. Expression of Estrus was defined as removal of ≥50% of the grey coating from the Estrotect® patch. Heifers that expressed Estrus at 66 h were inseminated then and heifers that had not expressed Estrus were inseminated at 90 h. Only heifers that failed to express Estrus by 90 h received gonadotropin-releasing hormone (GnRH; 100 μg im gonadorelin acetate) at the time of AI. At location one, blood samples were collected at PG and AI (66 h or 90 h) from all heifers to determine E2 concentration by radioimmunoassay, and transrectal ovarian ultrasound was performed to detail ovarian structures on a subset of heifers (n = 73) at both time points. The proportion of heifers expressing Estrus did not differ between treatments, either by 66 h (60%) or in total by 90 h (84%) after PG. Pregnancy rate to STAI did not differ between treatments (P = 0.3; 52%, 14-d CIDR®-PG; 50%, 18-d CIDR®-PG), or at the end of the 60 d breeding season (P = 0.2; 86%, 14-d CIDR®-PG; 82%, 18-d CIDR®-PG). No differences were detected in mean diameter of the dominant follicle at PG (P = 0.6; 10.9 ± 0.4 mm, 14-d CIDR®-PG; 11.0 ± 0.4 mm, 18-d CIDR®-PG) or at STAI (P = 0.3; 12.6 ± 0.4 mm, 14-d CIDR®-PG; 13.2 ± 0.4 mm, 18-d CIDR®-PG), nor were any differences observed between treatments in concentrations of E2 at PG (P = 0.8; 1.1 ± 0.19 pg/ml, 14-d CIDR®-PG; 1.1 ± 0.19 pg/ml, 18-d CIDR®-PG) or STAI (P = 0.6; 3.8 ± 0.19 pg/ml, 14-d CIDR®-PG; 3.6 ± 0.19 pg/ml, 18-d CIDR®-PG). These data indicate that duration of CIDR® treatment can be extended from 14 to 18 d, thus providing flexibility in scheduling without compromising reproductive outcomes.

  • comparison of long term progestin based Estrus Synchronization protocols in beef heifers
    Journal of Animal Science, 2010
    Co-Authors: D A Mallory, Mark R. Ellersieck, M F Smith, D J Wilson, D C Busch, D. J. Patterson
    Abstract:

    Two experiments evaluated long-term progestin-based Estrus-Synchronization programs on the basis of potential for use in facilitating fixed-time AI in estrous cycling and prepubertal beef heifers. In Exp. 1, heifers were assigned to 1 of 2 treatments by age, BW, and estrous cyclicity status. Heifers assigned to the melengestrol acetate-PGF 2α protocol (MGA-PG; n = 50) received MGA (0.5 mg·animal ―1 ·d ―1 ) in a 1.0-kg carrier from d 0 to 13 and were administered PGF 2α (25 mg, intramuscularly) 19 d after MGA withdrawal (d 32). Heifers assigned to the Show-Me-Synch protocol (n = 49) received a controlled internal drug release (CIDR) insert (1.38 g of progesterone) from d 2 to 16 followed by PGF 2α administration 16 d after CIDR removal (d 32). All heifers were fitted with HeatWatch Estrus-detection transmitters at the time of progestin removal for continuous Estrus detection through the synchronized period after PGF 2α . In Exp. 2, heifers (n = 396) were assigned to the same 2 treatments described in Exp. 1 by age, BW, and reproductive tract score. Heifers in Exp. 2, however, were fitted with HeatWatch Estrus-detection transmitters at PGF 2α to characterize Estrus-distribution patterns during the synchronized period after PGF 2α . Heifers in both experiments were inseminated approximately 12 h after the onset of Estrus. In Exp. 1, estrous response after PGF 2α and mean interval to Estrus after PGF 2α did not differ between MGA-PG and Show-Me-Synch treatments (P = 0.97). The variance for interval to Estrus after PGF 2α tended (P = 0.06) to be reduced among MGA-PG-treated heifers compared with Show-Me-Synch-treated heifers. Conception to AI, AI pregnancy, and final pregnancy rates did not differ (P > 0.1) between treatments. In Exp. 2, estrous response after PGF 2α was greater (P = 0.01) among Show-Me-Synch-treated heifers (92%) compared with MGA-PG-treated heifers (85%); however, mean interval to Estrus after PGF 2α did not differ (P = 0.74) between MGA-PG (57.4 ± 2.5 h) and Show-Me-Synch (56.2 ± 2.5 h) treatments. The variance for interval to Estrus after PGF 2α was reduced (P 0.1) between treatments. In summary, the Show-Me-Synch protocol compared favorably with the MGA-PG protocol on the basis of estrous response, synchrony of Estrus, and resulting fertility after treatment administration.

  • current concepts for Estrus Synchronization and timed insemination
    American Association of Bovine Practitioners Proceedings of the Annual Conference, 2001
    Co-Authors: W W Thatcher, D. J. Patterson, F Moreira, M Panciera, E R Jordan, C A Risco
    Abstract:

    The cattle industries have a wide range of reproductive technologies that are available to producers and veterinarians to program reproductive management with the use of Estrus Synchronization and timed insemination protocols. It is of paramount importance that users of this technology have a thorough understanding of the systems as to how they regulate pituitary, ovarian and uterine function. Major advancements have come about because we now understand how to control and coordinate ovarian follicular, corpus luteum and uterine functions in a manner that is conducive to normal fertility in cattle under different physiological conditions i.e., non-lactation, lactation, anEstrus, intensive and extensive management conditions etc. At this meeting in 1998, the various practical systems to control the estrous cycle in dairy animals were reviewed.30 Objective of this presentation is to provide an update of current reproductive strategies for Synchronization and timed insemination in dairy and beef cattle. The focus will be with the use of those pharmacological drugs available to the cattle industries in the United States. Effective Estrus Synchronization programs provide a number of advantages: cows or heifers are in Estrus at a predicted time which facilitates AI, and embryo transfer; time and labor expense for detection of Estrus are reduced; AI becomes more practical under extensive conditions; precise control of ovulation permits a timed insemination without the need for detection of Estrus; and specific timed treatments to improve embryo survival can be implemented effectively.

  • development of an Estrus Synchronization protocol for beef cattle with short term feeding of melengestrol acetate 7 11 synch
    Journal of Animal Science, 2000
    Co-Authors: F N Kojima, M C Lucy, M F Smith, B E Salfen, J F Bader, William A Ricke, D. J. Patterson
    Abstract:

    An Estrus Synchronization protocol (7-11 Synch) was developed to synchronize the first follicular wave and timing of ovulation in postpartum beef cows. In Exp. 1, follicular development and timing of ovulation in response to the following protocol were evaluated. Beef heifers (n = 12) and cows (n = 6), at random stages of the estrous cycle, were fed melengestrol acetate (MGA; .5 mg x animal(-1) x d(-1)) for 7 d and injected with PGF2alpha (PG; 25 mg) on the last day of MGA. A second injection of PG was administered 11 d after cessation of MGA. After the second injection of PG, Estrus was synchronized in 6/12 heifers and 3/6 cows. The interval to Estrus in heifers and cows was 54 and 64 h, respectively (P > .10). All animals exhibiting Estrus ovulated first-wave follicles. Animals that failed to respond to the second injection of PG were in Estrus later than 6 d after cessation of MGA and had corpora lutea that were unresponsive to the injection of PG. Based on the variation in interval to Estrus following the first PG injection on the last day of MGA feeding in Exp. 1, an injection of GnRH (100 microg) was added to the protocol 4 d after the cessation of MGA to ensure ovulation or luteinization of dominant follicles and Synchronization of first-wave follicular development. This revised protocol was termed "7-11 Synch." In Exp. 2, two Estrus Synchronization protocols were compared. Multiparous beef cows were stratified by breed and postpartum interval and randomly assigned to the 7-11 Synch (n = 44) or Select Synch protocols (GnRH injection followed by PG injection 7 d later; n = 45). Timing of Estrus after the last PG injection (0 h) ranged from 42 to 102 h in the 7-11 Synch group and -30 to 114 h in the Select Synch group. Eight cows (18%) in the Select Synch group exhibited Estrus 30 h before to 18 h after PG. Synchronized Estrus peaked between 42 and 66 h after the last PG injection, and a maximum number of cows were in Estrus at 54 h for both treatment groups. Synchrony of Estrus from 42 to 66 h was greater (P < .05) in 7-11 Synch (91%: 41/44) than in Select Synch cows (69%: 31/45). Artificial insemination pregnancy rate from 42 to 66 h was greater (P < .05) in the 7-11 Synch group (66%: 29/44) than in the Select Synch group (40%: 18/45). In summary, the 7-11 Synch protocol improved synchrony of Estrus without reducing fertility. This protocol has potential future application for fixed-time AI in beef cattle production systems.

M L Day - One of the best experts on this subject based on the ideXlab platform.

  • the strategic use of estradiol to enhance fertility and submission rates of progestin based Estrus Synchronization programs in dairy herds
    Journal of Animal Science, 2000
    Co-Authors: M L Day, C R Burke, V K Taufa, A M Day, K L Macmillan
    Abstract:

    Two experiments were performed to evaluate the efficacy of a progestin-based Estrus Synchronization program that incorporated the use of estradiol at the initiation of progestin treatment and at 48 h after progestin withdrawal (Exp. 2). In Exp. 1, cyclic, lactating dairy cows (n = 112) were assigned to receive either 1 (1mg) or 2 (2mg) mg of estradiol benzoate via an i.m. injection on d -9 (d 0 = initiation of the breeding season). All cows received an intravaginal progesterone-releasing insert (IPI; CIDR-B) on d -9. On d -2, the IPI was withdrawn and all cows were administered 500 microg of cloprostenol sodium. Beginning on d 0, cows were bred by AI upon detection of Estrus. Estrus was observed in similar proportions of cows in each treatment during the first 6 d of AI (90% across treatments), but the interval to Estrus was shorter (P < .05) in 1mg (1.26 +/- .18 d) than in 2mg (1.77 +/- .18 d). Conception and pregnancy rates did not vary among treatments; however, cows in Estrus on d 0 tended to be less fertile (P = .11) than those in Estrus on d 1. In Exp. 2, 408 cyclic cows from three herds were assigned to receive either no synchrony treatment (Control, n = 214) or the treatments described in Exp. 1 (1mg, n = 100; 2mg, n = 94). Anestrous cows from all herds received an IPI from d -9 to -2 (n = 143; AnEstrus). All cows in the 1mg, 2mg, and AnEstrus groups, with the exception of those detected in Estrus between d -1 and 0, also received 1 mg of estradiol benzoate on d 0. Greater than 90% of cows that received an IPI were in Estrus between d -1 and 3, and 92.1% of cows in the Control group were in Estrus by d 21. Conception rate to first service in 2mg (61.7%) was similar to Control (57.0%), tended to be higher (P = .06) than 1mg (49.0%), and was greater (P < .05) than AnEstrus (39.9%). The mean day of conception was earlier (P < .05) in the 2mg (d 13.1 +/- 2.0) than the Control (d 23.2 +/- 1.6) and AnEstrus (d 22.4 +/- 1.9) groups. Conception occurred earlier in 1mg (d 17.4 +/- 2.1) than in Control. The proportion of cows that were pregnant at the end of the breeding season tended (P = .09) to be greater in the 2mg and AnEstrus groups. This regimen of Estrus Synchronization improved reproductive competence in cyclic cows and resulted in similar reproductive performance in anestrous cows and untreated cyclic cows inseminated at a spontaneous Estrus.

  • development of a progestin based Estrus Synchronization program i reproductive response of cows fed melengestrol acetate for 20 days with an injection of progesterone
    Journal of Animal Science, 1998
    Co-Authors: L H Anderson, M L Day
    Abstract:

    We designed two experiments to determine the efficacy of an Estrus control system in cows that combined long-term progestin exposure (20 d) with an acute increase in progesterone concentration. In Exp. 1, cows (n = 30) were fed either melengestrol acetate (MGA; .5 mg x cow(-1) x d(-1)) or ground ear corn (MGA carrier) for 20 d. On d -15 (last day of MGA feeding = d 0), cows were administered 25 mg of PGF2alpha to regress the corpus luteum (CL) and establish an environment conducive to the development of persistent follicles. To synchronously regress persistent follicles, cows fed MGA (n = 15) were injected with 200 mg of progesterone on d -2 (MGA-P), and the cows fed the MGA carrier were not treated (CONT; n = 15). Cows in the CONT group were artificially inseminated 12 h after detection of spontaneous Estrus from d -20 to d 8. Estrus was observed, and all cows in the MGA-P group were artificially inseminated during the period of Estrus Synchronization (SYNC; d 1 to 8). No difference in conception rate was observed between treatments. In Exp. 2, postpartum cows (n = 113) received either the MGA-P (n = 56) or CONT (n = 57) treatment. More (P < .05) cows were observed in Estrus during SYNC in the MGA-P (50%) than in the CONT (28%) group. Of the cows in the MGA-P group that were not observed in Estrus during SYNC, 50% were in Estrus for the first time 23 to 29 d after MGA withdrawal (SYNC2), suggesting that these cows ovulated without observable Estrus during SYNC. Estrus was observed for the first time during SYNC2 in more (P < .05) cows in the MGA-P (25%) than in the CONT (7%) group. Conception rate at the synchronized Estrus, pregnancy rate, and interval to first service and pregnancy were similar between treatments. We conclude that administration of MGA-P results in the Synchronization and(or) induction of a fertile Estrus in cows.

  • development of a progestin based Estrus Synchronization program ii reproductive response of cows fed melengestrol acetate for 14 days with injections of progesterone and prostaglandin f2alpha
    Journal of Animal Science, 1998
    Co-Authors: C M Mcdowell, L H Anderson, R P Lemenager, D A Mangione, M L Day
    Abstract:

    We tested the efficacy of an Estrus control system designed to provide optimal control of follicular development. In Exp. 1, postpartum cows (n = 133) and yearling heifers (n = 57) were fed either .5 mg x female(-1) x d(-1) of melengestrol acetate (MGA) or the carrier for MGA from d -13 to d 0 (d 0 = last day of MGA feeding). All females received 25 mg of PGF2alpha (i.m.) on d -13 and 0. On d -6, cows and heifers fed MGA were administered an i.m. injection of progesterone (200 mg; MGA/P4), and those fed the corn carrier (2XPGF2alpha) received no progesterone. Beginning on d 1, females were bred by AI from d 1 to at least d 5. During the Estrus Synchronization period (d 1 to d 5), more (P < .05) postpartum cows were observed in Estrus (70.1 vs 42.4%), the timing of Estrus was more (P < .05) precise, conception rate was similar, and pregnancy rate was higher (P < .05) in the MGA/P4 than in the 2XPGF2alpha treatment. More (P < .05) cows that were anestrous at the beginning of the breeding season were in Estrus during the Synchronization period in the MGA/P4 (55.8%) than in the 2XPGF2alpha (28.6%) treatment. In heifers, Estrus was synchronized in over 90% of females, and neither conception nor pregnancy rate during the Synchronization period differed between treatments. In Exp. 2, postpartum cows (n = 122) and heifers (n = 84) received treatments (MGA/P4 or 2XPGF2alpha) as described for Exp. 1 with one exception. In the MGA/ P4 treatment, progesterone was administered on d -7 rather than d -6. Females were bred by AI from d 1 to 5. The Estrus response and conception rate during the Synchronization period did not differ between treatments for either cows or heifers. We conclude that the progestin-based estrous Synchronization system used in this study effectively synchronized an Estrus of normal fertility in cyclic cows and induced a majority of anestrous cows to reinitiate estrous cycles.

C L Love - One of the best experts on this subject based on the ideXlab platform.

  • estrous cycle characteristics and response to Estrus Synchronization in mammoth asses equus asinus americanus
    Theriogenology, 1999
    Co-Authors: T L Blanchard, T S Taylor, C L Love
    Abstract:

    Abstract Breeding records from a herd of mammoth asses (Equus asinus americanus) maintained on pasture in southeast Texas from 1990 to 1998 were reviewed. Jennies were pasture or hand mated, and Estrus was either observed while the jennies were on pasture or when exposed to a jack after being penned. Eighty-one Estrus periods and 43 diEstrus intervals were recorded in 33 jennies over 4 seasons of the year (January–March, April–June, July–September, and October–December). Estrous cycle length and the duration of Estrus were similar among seasons. Over all seasons, estrous cycle length was 23.3 ± 2.6 d, duration of Estrus was 5.9 ± 2.1 d, and diEstrus length was 17.4 ± 2.6 d (mean ± SD). During these same 9 yr, 58 injections of PGF 2 α (5 mg, im) were administered to 38 jennies without regard to stage of estrous cycle. Seventy-six percent (44/58) of the jennies showed signs of Estrus after PGF 2 α treatment, with an interval to Estrus of 4.4 ± 1.6 d and a duration of Estrus of 5.6 ± 1.7 d. Two Estrus Synchronization schemes were also assessed. Trial 1 was performed in October to November 1996, and Trial 2 was performed in February to March 1998. In Trial 1 (Group PE+PGF, n=10), each jenny was injected intramuscularly once daily for 10 d with 150 mg progesterone and 10 mg estradiol-17β in sesame oil, and PGF 2 α (10 mg) was injected intramuscularly on the last day of treatment. In Trial 2 (Group PGF-2X, n=11), each jenny was injected intramuscularly twice, 16 d apart, with 10 mg PGF 2 α. All Group PE+PGF jennies responded to treatment. One jenny in Group PGF-2X did not respond to either injection of PGF 2 α, while 2 jennies responded to the first but not the second PGF 2 α injection (8 of 11 jennies returned to Estrus and ovulated after the second PGF 2 α injection). Duration of Estrus was 6.8 ±1.9 d for Group PE + PGF and 7.1 ± 1.8 d for Group PGF-2X jennies. Interval to Estrus and interval to ovulation following the last treatment were 9.0 ± 0.9 d and 14.5 ± 1.7 d, respectively, in Group PE+PGF jennies, and 4.5 ± 0.9 d and 10.4 ± 1.8 d, respectively, for Group PGF-2X jennies. In summary, estrous cycle characteristics of mammoth asses are similar to those reported for standard jennies, and Estrus Synchronization schemes used in horses are effective in mammoth asses.

  • estrous cycle characteristics and response to Estrus Synchronization in mammoth asses equus asinus americanus
    Theriogenology, 1999
    Co-Authors: T L Blanchard, T S Taylor, C L Love
    Abstract:

    Breeding records from a herd of mammoth asses (Equus asinus americanus) maintained on pasture in southeast Texas from 1990 to 1998 were reviewed. Jennies were pasture or hand mated, and Estrus was either observed while the jennies were on pasture or when exposed to a jack after being penned. Eighty-one Estrus periods and 43 diEstrus intervals were recorded in 33 jennies over 4 seasons of the year (January-March, April-June, July-September, and October-December). Estrous cycle length and the duration of Estrus were similar among seasons. Over all seasons, estrous cycle length was 23.3 +/- 2.6 d, duration of Estrus was 5.9 +/- 2.1 d, and diEstrus length was 17.4 +/- 2.6 d (mean +/- SD). During these same 9 yr, 58 injections of PGF2 alpha (5 mg, i.m.) were administered to 38 jennies without regard to stage of estrous cycle. Seventy-six percent (44/58) of the jennies showed signs of Estrus after PGF2 alpha treatment, with an interval to Estrus of 4.4 +/- 1.6 d and a duration of Estrus of 5.6 +/- 1.7 d. Two Estrus Synchronization schemes were also assessed. Trial 1 was performed in October to November 1996, and Trial 2 was performed in February to March 1998. In Trial 1 (Group PE + PGF, n = 10), each jenny was injected intramuscularly once daily for 10 d with 150 mg progesterone and 10 mg estradiol-17 beta in sesame oil, and PGF2 alpha (10 mg) was injected intramuscularly on the last day of treatment. In Trial 2 (Group PGF-2X, n = 11), each jenny was injected intramuscularly twice, 16 d apart, with 10 mg PGF2 alpha. All Group PE + PGF jennies responded to treatment. One jenny in Group PGF-2X did not respond to either injection of PGF2 alpha, while 2 jennies responded to the first but not the second PGF2 alpha injection (8 of 11 jennies returned to Estrus and ovulated after the second PGF2 alpha injection). Duration of Estrus was 6.8 +/- 1.9 d for Group PE + PGF and 7.1 +/- 1.8 d for Group PGF-2X jennies. Interval to Estrus and interval to ovulation following the last treatment were 9.0 +/- 0.9 d and 14.5 +/- 1.7 d, respectively, in Group PE + PGF jennies, and 4.5 +/- 0.9 d and 10.4 +/- 1.8 d, respectively, for Group PGF-2X jennies. In summary, estrous cycle characteristics of mammoth asses are similar to those reported for standard jennies, and Estrus Synchronization schemes used in horses are effective in mammoth asses.

C Peris - One of the best experts on this subject based on the ideXlab platform.

  • effect of Estrus Synchronization on daily somatic cell count variation in goats according to lactation number and udder health status
    Journal of Dairy Science, 2013
    Co-Authors: Amine Mehdid, J R Diaz, A Marti, G Vidal, C Peris
    Abstract:

    Abstract Two repeated experiments were carried out in 2 different years to study the effect of Estrus on somatic cell count (SCC) in dairy goats. In the first year, 36 Murciano-Granadina goats were used [12 primiparous and 24 multiparous; 22 healthy and 14 with an intramammary infection (IMI)] and, after a 6-d pre-experimental period, were divided into 2 groups according to lactation number, udder health status, SCC, and milk production. One group was kept as a control, whereas the other received an Estrus Synchronization hormonal treatment lasting 11d. At 24, 48, and 72h after cessation of the hormone treatment, goats were placed in contact with a buck to confirm that they were in Estrus. For 32 consecutive days (6 pre-experimental, 11 in hormone treatment, and 15 post-treatment) the SCC per gland and udder were monitored in all animals. In the second year, we repeated the same experimental design using a total of 38 Murciano-Granadina breed goats (12 primiparous and 26 multiparous; 26 healthy and 12 with IMI). Throughout this experiment, milk yield and composition were also recorded daily for each goat. Upon termination of the hormonal treatment, the SCC in udder milk increased significantly in the treatment group compared with the control group over 3 consecutive days. This increase was observed for year (1 and 2), parity (primiparous and multiparous), and udder health status (healthy and IMI). The log 10 SCC (cells/mL) increased from 5.5±0.09 before Estrus to 6.04±0.09 during treatment; therefore, the geometric mean of the SCC increased 3.5 times during treatment. The maximum values obtained in healthy glands of primiparous goats (geometric mean=0.37 million cells/mL) were lower than in healthy glands (1.1 million cells/mL) or infected glands (1.7 million cells/mL) of multiparous goats. The increase in SCC observed during Estrus (200% increase in geometric means) could not be explained by the changes in milk production, which only fell by 13%. During Estrus, the percentage of protein and dry matter in the milk also increased significantly. We concluded that it is necessary to consider the presence of Estrus to correctly interpret milk SCC, as an indirect method for detecting IMI or as a commercial milk quality parameter.

Syed Mohammed Khursheed Naqvi - One of the best experts on this subject based on the ideXlab platform.

  • effect of environmental factors on Estrus Synchronization and artificial insemination success in farmers flock in sheep under semi arid tropical region
    Reproduction in Domestic Animals, 2020
    Co-Authors: Dinesh Kumar, Krishnappa Balaganur, Syed Mohammed Khursheed Naqvi
    Abstract:

    Environmental cues in the different seasons might influence the Estrus and lambing percentages. The present study was conducted to assess the effect of environmental factors on Estrus Synchronization (ES) and artificial insemination success in sheep. During the period from 2012 to 2017, a total of 1,197 ewes of Kheri and Malpura breeds of 34 farms originating from 10 villages were synchronized for Estrus and then fixed-time artificial insemination (FTAI) was done. Oestrous Synchronization was done by intravaginal progesterone sponges and eCG protocol. Fixed-time cervical insemination was performed 48 and 56 hr after sponge removal in ewes exhibiting Estrus, using liquid chilled semen containing 100 million sperm per dose of Patanwadi/Malpura rams. Mean sunshine hours, maximum and minimum ambient temperatures, temperature amplitude, mean relative humidity (RH), temperature-humidity index (THI), mean temperature during sponge-in to sponge-out-12-day period, sponge-out and next day, AI day and AI to next 15 days have been calculated. The Estrus response and lambing percentage were higher (p < .05) when ES and FTAI were done during hot-humid with rainfall season. Successful (p < .05) ES occur when the minimum temperature was higher in cold-humid season, and the sunshine hour was higher in hot-humid with scanty rainfall season during sponge-in to sponge-out period. The success of the lambing percentage was higher (p < .05) when maximum temperature, minimum temperature, mean temperature and THI was higher on the day of AI and the next 15-day period, irrespective of the season. The success of FTAI indicates the adaptability of the local breed to tolerate the harsh climate of the hot semi-arid region without much hindrance in lambing percentages.

  • effect of breeding season on fertility of sheep following Estrus Synchronization and fixed time artificial insemination under field conditions in semi arid tropical region
    Biological Rhythm Research, 2016
    Co-Authors: Dinesh Kumar, Rajiv Gulyani, Krishnappa Balaganur, Syed Mohammed Khursheed Naqvi
    Abstract:

    AbstractAccelerated lambing system is heavily reliant on reproductive technologies meant to enable off the season breeding in sheep. Therefore, the present study was programmed to assess the effect of breeding season (BS) on fertility of sheep following Estrus Synchronization (ES) and fixed time artificial insemination (FTAI). A total of 248 and 365 ewes were synchronized and inseminated during the BS (Febuary–March and July–September) and non-breeding season (NBS) respectively, during 2012–14. Synchronization of Estrus was done by AVIKESIL-S, intra-vaginal progesterone sponges kept in situ in vagina for 12 days. 200 IU eCG was administered intramuscularly on 12th day after sponge withdrawal. FTAI was performed twice in ewes exhibiting signs of Estrus at 48 and 56h after sponge removal, using liquid chilled semen of Patanwadi/Malpura rams containing 100 million sperm. Breeding season had no significant (p<0.05) effect on Estrus Synchronization. The estrous responses during the BS and NBS were 84.68% and 8...

  • Estrus Synchronization and fixed-time artificial insemination in sheep under field conditions of a semi-arid tropical region
    Tropical Animal Health and Production, 2015
    Co-Authors: Davendra Kumar, Debabrata Sethi, Rajiv Gulyani, Syed Mohammed Khursheed Naqvi
    Abstract:

    A study was conducted to assess the success of Estrus Synchronization and fixed-time artificial insemination (FTAI) in sheep under field conditions of a semi-arid tropical region. A total of 471 ewes belonging to 17 farmers of four villages in Tonk district of Rajasthan (Jelmiya, Dhani Jaisinghpura, Tantiya and Bheepur) were synchronized for Estrus during the years 2011 and 2012. Synchronization of Estrus was done by AVIKESIL-S, cost-effective intra-vaginal sponges developed by the Institute and eCG protocol. The sponges were kept in situ in the vagina for 12 days and 200 IU eCG (Folligon, Intervet) was administered intramuscularly at the time of sponge withdrawal on the 12th day. Fixed-time cervical insemination was performed twice in ewes exhibiting Estrus (restlessness, shaking of tail, slightly swollen vulva, moist and reddish cervical external os), 48 and 56 h after sponge removal, using liquid chilled semen of Patanwadi/Malpura rams containing 100 million sperm per dose. The Estrus response recorded was 79.4 % (374/471) and lambing rate was 60.42 % (226/374). It may be concluded from the encouraging results of the present study that FTAI can be used effectively to take advantage of both the genetic improvement and economic benefit that can be realized by the use of Estrus Synchronization in conjunction with artificial insemination (AI).