Letter to Editor
BibTex RIS Cite

Conception rate following timed artificial insemination protocols in dairy heifers synchronised by PGF2α and GnRH

Year 2011, Volume: 58 Issue: 2, 135 - 139, 01.06.2011
https://doi.org/10.1501/Vetfak_0000002463

Abstract

This study aimed to develop a timed artificial insemination (TAI) protocol using PGF2α and GnRH with acceptable pregnancy rate in dairy heifers. Dairy heifers (n=290), aged between 13 and 26 months (mean 16.1 months), were used in this study. Heifers were synchronized with two PGF2α administrations by 14 d intervals. After the second PGF2α , heifers were randomly assigned into two groups. In Group 1 (n=155), GnRH was given at 56h following 2nd PGF2α and TAI was performed at 1618h after the GnRH. In Group 2 (n=135), GnRH was administered at 72h after 2nd PGF2α , at the time of TAI. Ultrasonography was performed at both PGF2α administrations to determine cyclicity, at the time of TAI to measure ovulatory follicle size, 7 d after TAI to determine ovulation, 31 and 62 d post-AI to determine pregnancy. Ovulatory follicle size at the time of TAI was not significantly different between groups (12.8±1.6 mm and 13.2±1.8 mm in group 1 and 2, respectively). Synchronization rate was similar in group 1 (85.2%;132/155) and in group 2 (91.1%;123/135). Conception rate (CR) at 31 d was not different in group 1 (59.8% ;79/132) and in group 2 (55.3%;68/123). Embryonic loss (7.6%; 6/79 and 7.4%; 5/68 in group 1 and 2 respectively) was not different. Gender ratio of the calves was found different between groups. Proportion of the female calves born were higher (P=0.03) in group 1 (63.3%; 38/60) than in group 2 (42.0%; 21/50). In conclusion, both protocols can be used in order to eliminate estrous detection in large dairy herds. Although GnRH administration at the time of TAI was found to be useful to reduce handling of heifers, GnRH can be applied 16-18 h before AI to achive higher female calves ratio in large dairy farms

References

  • Bader JF, Kojima FN, Schafer DJ, Stegner JE, Ellersieck MR, Smith MF, Patterson DJ (2005): A comparison of progestin-basedprotocols to synchronize ovulation and facilitate fixed-time artificial insemination in postpartum beef cows. J Anim Sci, 83, 136–43.
  • Brusveen DJ, Cunha AP, Silva CD, Cunha PM, Sterry RA, Silva EP, Guenther JN, Wiltbank MC (2008): Altering the time of the second gonadotropin-releasing hormone injection and artificial insemination (A I) during Ovsynch affects pregnancies per AI in lactating dairy cows. J Dairy Sci, 91, 1044–52.
  • Bucher A, Kasimanickam R, Hall JB, Dejarnette JM, Whittier WD, Kahn W, Xu Z (2009): Fixed-time Al pregnancy rate following insemination with frozen-thawed or fresh-extended semen in progesterone supplemented CO-Synch protocol in beef cows. Theriogenology, 71, 180–5.
  • Busch DC, Wilson DJ, Schafer DJ, Leitman NR, Haden JK, Ellersieck MR, Smith MF, Patterson DJ (2007): Comparison of progestin-based estrus synchronization protocols before fixed-time artificial insemination on pregnancy rate in beef heifers. J Anim Sci, 85, 1933–9.
  • Clutton-Brock, TH, Iason GR (1986): Sex ratio variation in mammals. Q Rev Biol, 61, 339–74.
  • Dalton JC, Manzo R, Ahmadzadeh A, Shafii B, Price WJ, DeJarnette JM (2005): Short communication: Conception rates following detection of estrus and timed AI in dairy cows synchronized using GnRH and PGF2alpha. J Dairy Sci, 88, 4313–6.
  • Donovan GA, Bennett FL, Frederick SP (2003): Factors associated with first service conception rates in artificially inseminated nulliparous Holstein heifers. Theriogenology, 60, 67–75.
  • Fonseca FA, Britt JH, McDaniel BT, Wilk JC, Rakes AH (1983): Reproductive traits of Holstein and Jerseys. Effects of age, milk yield, and clinical abnormalities on involution of cervix and uterus, ovulation, estrous cycles, detection of estrus, conception rate, and days open. J Dairy Sci, 66, 1128–47.
  • Fricke PM, Guenther JN, Wiltbank MC (1998): Effect of decreasing the dose of GnRH used in a protocol for synchronization of ovulation and timed AI in lactating dairy cows. Theriogenology, 50, 1275–84.
  • Galvâo KN, Sâ Filho MF, Santos JE (2007): Reducing the interval from pre synchronization to initiation of timed artificial insemination improves fertility in dairy cows. J Dairy Sci, 9, 4212–8.
  • Gatius FL (2000): Short Synchronization System For Estrus Cycles in Dairy Heifers: A Preliminary Report. Theriogenology, 54,1185–90.
  • Geary TW, Downing ER, Bruemmer JE, Whittier JC (1998): Ovarian and estrous response of suckled beef cows to the select synch estrous synchronization protocol. J Anim Sci, 16, 1–5.
  • Gutie'rrez-Ada'n A, Pe'rez-Garnelo J, Garde JJ, Pe'rez-Guzman M, Pinatado B, De La Fuente J (1999): Relationship between sex ratio and time of insemination according to both time of ovulation and matiirational state of oocyte. Zygote, 7, 37–43.
  • Jordan ER, Schouten MJ, Quast JW, Belschner AP,
  • Tomaszewski MA (2002): Comparison of two timed artificial insemination (TAI) protocols for management of first insemination postpartum. J Dairy Sci, 85, 1002–8.
  • Larson JE, Lamb GC, Stevenson JS, Johnson SK, Day
  • ML, Geary TW, Kesler DJ, DeJarnette JM, Schrick FN, DiCostanzo A, Arseneau JD (2006). Synchronization of estrus in suckled beef cows for detected estrus and artificial insemination and timed artificial insemination using gonadotropin-releasing hormone, prostaglandin F2a, and progesterone. J Anim Sci, 84, 332–42.
  • Larson LL, Ball PJH (1992): Regulation of estrous cycles
  • in dairy cattle: a review. Theriogenology, 38, 255–67.
  • Lucy MC, Billings HJ, Butler WR, Ehnis LR, Fields
  • MJ, Kesler DJ, Kinders JE, Mattos RC, Short RE, Thatcher WW, Wettemann RP, Yelich JV, Hafs HD (2001): Efficacy of an intravaginal progesterone insert and an injection of PGF2α for synchronizing estrus and shortening the interval to pregnancy in postpartum beef cows, peripubertal beef heifers and dairy heifers. J Anim Sci, 79, 982–95.
  • Melendez P, Gonzalez G, Aguilar E, Loera O, Risco C,
  • Archbald LF (2006): Comparison of two estrus- synchronization protocols and timed artificial insemination in dairy cattle. J Dairy Sci, 89, 4567–72.
  • Peeler ID, Nebel RL, Pearson RE, Swecker WS, Garcia
  • A (2004): Pregnancy rates after timed AI of heifers following removal of intravaginal progesterone inserts. J Dairy Sci, 87, 2868–73.
  • Perry GA, Smith MF, Lucy MC, Green JA, Parks TE, MacNeil MD (2005): Relationship between follicle size at insemination and pregnancy success. Proc Natl Acad Sci USA, 102, 5268–73.
  • Perry GA, Smith MF, Patterson DJ (2002): Evaluation of a fixed-time artificial insemination protocol for postpartum suckled beef cows. J Anim Sci, 80, 3060–4.
  • Pursley JR, Mee MO, Wiltbank MC (1995): Synchronization of ovulation in dairy cows using PGF2α and GnRH. Theriogenology, 44, 915–23.
  • Pursley JR, Silcox RW, Wiltbank MC (1998): Effect of time of artificial insemination on pregnancy rates, calving rates, pregnancy loss, and gender ratio after synchronization of ovulation in lactating dairy cows. J Dairy Sci, 81, 2139–44.
  • Pursley JR, Wiltbank MC, Stevenson JS, Ottobre JS, Garverick HA, Anderson LL (1997): Pregnancy rates per artificial insemination for cows and heifers inseminated at a synchronized ovulation or synchronized estrus. J Dairy Sci, 80, 295–300.
  • Rantala MH, Katila T, Taponen J (2009): Effect of time interval between prostaglandin F(2alpha] and GnRH treatments on occurrence of short estrous cycles in cyclic dairy heifers and cows. Theriogenology, 71, 930–8.
  • Rivera H, Lopez H, Fricke PM (2004): Fertility of holstein dairy heifers after synchronization of ovulation and timed AI or AI after removed tail chalk. J Dairy Sci, 87, 2051–61.
  • Rivera H, Lopez H, Fricke PM (2005): Use of intravaginal progesteronereleasing inserts in a synchronization protocol before timed AI and for synchronizing return to estrus in Holstein heifers. J Dairy Sci, 88, 957–8.
  • Rivera H, Sterry RA, Fricke PM (2006): Presynchronization with gonadotropin-releasing hormone does not improve fertility in Holstein heifers. J Dairy Sci, 89, 3810–16.
  • Sâ Filho OG, Vilela ER, Geary TW, Vasconcelos JL (2009): Strategies to improve fertility in postpartum multiparous Bos indicus cows submitted to a fixed-time insemination protocol with gonadotropin-releasing hormone and prostaglandin F2alpha.. J Anim Sci, 87, 2806–14.
  • Sartori R Fricke PM, Ferreira JC, Ginther OJ, Wiltbank MC (2001): Follicular deviation and acquisition of ovulatory capacity in bovine follicles. Biol Reprod, 65, 1403–09.
  • Schafer DJ, Busch DC, Smith MF, Patterson DJ (2006): Characterization of follicular dynamics, timing of estrus, and response to GnRH and PG in replacement beef heifers after presynchronization with a 14-day CIDR. J Anim Sci, 84, (Suppl. 1): 49.
  • Souza AH, Gumen A, Silva EPB, Cunha AP, Guenther JN, Peto CM,Caraviello DZ and Wiltbank MC (2007): Supplementation with estradiol-17p before the last gonadotropin-releasing hormone injection of the ovsynch protocol in lactating dairy cows. J Dairy Sci, 90, 4623–34.
  • Stevenson JS, Smith JF, Hawkins DE (2000): Reproductive outcomes for dairy heifers treated with combinations of prostaglandin F2a, norgestomet, and gonadotropin-releasing hormone. J Dairy Sci, 83, 2008– 15.
  • Thompson KE, Stevenson JS, Lamb GC, Grieger DM, Loest CA (1999): follicular, hormonal, and pregnancy responses of early postpartum suckled beef cows to GnRH, norgestomet, and PGF. J Anim Sci, 77, 1823–32.
  • Vasconcelos JLM, Silcox RW, Rosa GJM, Pursley JR, Wiltbank MC (1999): Synchronization rate, size of the ovulatory follicle, and pregnancy rate after synchronization of oviilation beginning on different days of the estrous cycle in lactating dairy cows. Theriogenology, 52, 1067–78.
  • Wolfenson D, Inbar G, Roth Z, Kaim M, Bloch A, Braw-Tal R (2004): Follicular dynamics and concentrations of steroids and gonadotropin in lactating cows and nulliparoits heifers. Theriogenology, 62, 1042– 55.
  • Xu ZZ, Burton LJ, Macmillan KL (1996): Reproductive performance of lactating dairy cows following oestrus synchronisation with progesterone, oestradiol andprostaglandin. NZ Vet J, 44, 99–104.
  • Xu ZZ, Burton LJ (2000): Estrus synchronization of lactating dairy cows with GnRH, progesterone, and prostaglandin F2 alpha. J Dairy Sci, 83, 471–6. Geliş tarihi: 18.10.2010 / Kabul tarihi: 04.11.2010 Address for correspondence: DVM, PhD Umut Taşdemir, Lalahan Livestock Central Research Institute, 06852 e-mail: tasdemiru@gmail.com

PGF2α ve GnRH Kullanılarak Senkronize Edilen Düvelerde Zaman Ayarlı SuniTohumlama SonrasmdaElde Edilen Gebelik Oranları

Year 2011, Volume: 58 Issue: 2, 135 - 139, 01.06.2011
https://doi.org/10.1501/Vetfak_0000002463

Abstract

Bu çalışmanın amacı GnRH ve PGF2α kullanılarak senkronize edilen düvelerde, östrüs kontrolleri yapılmadan uygulanan zaman ayarlı suni tohumlama sonrasında istenilen düzeyde gebelik oranı elde etmekti. Çalışmada yaşları 13 ile 24 ay arasında değişen (ortalama 16.1) düveler (n=290) kullanıldı. Düveler 14 gün ara ile uygulanan PGF2α ile senkronize edildi ve ikinci PGF2α uygulaması sonrası rastgele iki gruba ayrıldı. Grup l'e (n=155) ikinci PGF2α uygulamasını takiben 56. saat GnRH ve GnRH uygulamasını taiben 16-18. saat zaman ayarlı suni tohumlama yapıldı. Grup 2'ye ise (n=135) ikinci PGF2α uygulamasını takiben 72. saatte suni tohumlama GnRH ile birlikte uygulandı. Ovaryumların siklik olup olmadığını belirlemek amacıyla her iki PGF2αuygulaması sırasında, ovaryumlarda folliküllerin çapını belirmek amacıyla suni tohumlama ile eş zamanlı olarak, ovulasyon oranını belirlemek amacıyla suni tohumlamayı takiben 7. gün, gebelik oranını belirlemek amacıyla suni tohumlamayı takiben 31 ve 62. günlerde ultrasonografi uygulaması yapıldı. Suni tohumlama ile eş zamanlı olarak belirlenen follikül çaplarında gruplar arasında herhangibir farklılık yoktu (sırasıyla grup 1 ve 2 de 12.8±1.6 mm 13.2±1.8 mm). Senkronizasyon oranları gruplar arasında benzerdi (%85.2; 132/155 grup 1 ve %91.1; 123/135 grup 2). 31. günde belirlenen gebelik oranları değerlendirildiğinde gruplar arasında farklılık yoktu (% 59.8; 79/132 grup 1 ve % 55.3; 68/123 grup 2). Embriyonik kayıp gruplar arasında farklı değildi (sırasıyla grup 1 ve 2 de %7.6; 6/79, %7.4; 5/68). Gruplar arasında cinsiyet oranları farklı belirlendi. Dişi buzağı oranı grup 1 de (%63.3; 38/60) grup 2'ye oranla (%42.0; 21/50) daha yüksek bulundu (P<0.05). Sonuç olarak, her iki protokolünde senkronizasyon amacıyla büyük sürü popülasyonuna sahip kızgınlık kontrolleri yapılmayan süt sığırcılığı işletmelerinde uygulanabileceği görüldü. Suni tohumlama uygulaması ile eş zamanlı olarak yapılan GnRH uygulamasının işletmede işçiliği azaltmasına rağmen, GnRH uygulamasının 16-18 saat önce yapılmasının dişi buzağı oranını arttırdığı belirlendi

References

  • Bader JF, Kojima FN, Schafer DJ, Stegner JE, Ellersieck MR, Smith MF, Patterson DJ (2005): A comparison of progestin-basedprotocols to synchronize ovulation and facilitate fixed-time artificial insemination in postpartum beef cows. J Anim Sci, 83, 136–43.
  • Brusveen DJ, Cunha AP, Silva CD, Cunha PM, Sterry RA, Silva EP, Guenther JN, Wiltbank MC (2008): Altering the time of the second gonadotropin-releasing hormone injection and artificial insemination (A I) during Ovsynch affects pregnancies per AI in lactating dairy cows. J Dairy Sci, 91, 1044–52.
  • Bucher A, Kasimanickam R, Hall JB, Dejarnette JM, Whittier WD, Kahn W, Xu Z (2009): Fixed-time Al pregnancy rate following insemination with frozen-thawed or fresh-extended semen in progesterone supplemented CO-Synch protocol in beef cows. Theriogenology, 71, 180–5.
  • Busch DC, Wilson DJ, Schafer DJ, Leitman NR, Haden JK, Ellersieck MR, Smith MF, Patterson DJ (2007): Comparison of progestin-based estrus synchronization protocols before fixed-time artificial insemination on pregnancy rate in beef heifers. J Anim Sci, 85, 1933–9.
  • Clutton-Brock, TH, Iason GR (1986): Sex ratio variation in mammals. Q Rev Biol, 61, 339–74.
  • Dalton JC, Manzo R, Ahmadzadeh A, Shafii B, Price WJ, DeJarnette JM (2005): Short communication: Conception rates following detection of estrus and timed AI in dairy cows synchronized using GnRH and PGF2alpha. J Dairy Sci, 88, 4313–6.
  • Donovan GA, Bennett FL, Frederick SP (2003): Factors associated with first service conception rates in artificially inseminated nulliparous Holstein heifers. Theriogenology, 60, 67–75.
  • Fonseca FA, Britt JH, McDaniel BT, Wilk JC, Rakes AH (1983): Reproductive traits of Holstein and Jerseys. Effects of age, milk yield, and clinical abnormalities on involution of cervix and uterus, ovulation, estrous cycles, detection of estrus, conception rate, and days open. J Dairy Sci, 66, 1128–47.
  • Fricke PM, Guenther JN, Wiltbank MC (1998): Effect of decreasing the dose of GnRH used in a protocol for synchronization of ovulation and timed AI in lactating dairy cows. Theriogenology, 50, 1275–84.
  • Galvâo KN, Sâ Filho MF, Santos JE (2007): Reducing the interval from pre synchronization to initiation of timed artificial insemination improves fertility in dairy cows. J Dairy Sci, 9, 4212–8.
  • Gatius FL (2000): Short Synchronization System For Estrus Cycles in Dairy Heifers: A Preliminary Report. Theriogenology, 54,1185–90.
  • Geary TW, Downing ER, Bruemmer JE, Whittier JC (1998): Ovarian and estrous response of suckled beef cows to the select synch estrous synchronization protocol. J Anim Sci, 16, 1–5.
  • Gutie'rrez-Ada'n A, Pe'rez-Garnelo J, Garde JJ, Pe'rez-Guzman M, Pinatado B, De La Fuente J (1999): Relationship between sex ratio and time of insemination according to both time of ovulation and matiirational state of oocyte. Zygote, 7, 37–43.
  • Jordan ER, Schouten MJ, Quast JW, Belschner AP,
  • Tomaszewski MA (2002): Comparison of two timed artificial insemination (TAI) protocols for management of first insemination postpartum. J Dairy Sci, 85, 1002–8.
  • Larson JE, Lamb GC, Stevenson JS, Johnson SK, Day
  • ML, Geary TW, Kesler DJ, DeJarnette JM, Schrick FN, DiCostanzo A, Arseneau JD (2006). Synchronization of estrus in suckled beef cows for detected estrus and artificial insemination and timed artificial insemination using gonadotropin-releasing hormone, prostaglandin F2a, and progesterone. J Anim Sci, 84, 332–42.
  • Larson LL, Ball PJH (1992): Regulation of estrous cycles
  • in dairy cattle: a review. Theriogenology, 38, 255–67.
  • Lucy MC, Billings HJ, Butler WR, Ehnis LR, Fields
  • MJ, Kesler DJ, Kinders JE, Mattos RC, Short RE, Thatcher WW, Wettemann RP, Yelich JV, Hafs HD (2001): Efficacy of an intravaginal progesterone insert and an injection of PGF2α for synchronizing estrus and shortening the interval to pregnancy in postpartum beef cows, peripubertal beef heifers and dairy heifers. J Anim Sci, 79, 982–95.
  • Melendez P, Gonzalez G, Aguilar E, Loera O, Risco C,
  • Archbald LF (2006): Comparison of two estrus- synchronization protocols and timed artificial insemination in dairy cattle. J Dairy Sci, 89, 4567–72.
  • Peeler ID, Nebel RL, Pearson RE, Swecker WS, Garcia
  • A (2004): Pregnancy rates after timed AI of heifers following removal of intravaginal progesterone inserts. J Dairy Sci, 87, 2868–73.
  • Perry GA, Smith MF, Lucy MC, Green JA, Parks TE, MacNeil MD (2005): Relationship between follicle size at insemination and pregnancy success. Proc Natl Acad Sci USA, 102, 5268–73.
  • Perry GA, Smith MF, Patterson DJ (2002): Evaluation of a fixed-time artificial insemination protocol for postpartum suckled beef cows. J Anim Sci, 80, 3060–4.
  • Pursley JR, Mee MO, Wiltbank MC (1995): Synchronization of ovulation in dairy cows using PGF2α and GnRH. Theriogenology, 44, 915–23.
  • Pursley JR, Silcox RW, Wiltbank MC (1998): Effect of time of artificial insemination on pregnancy rates, calving rates, pregnancy loss, and gender ratio after synchronization of ovulation in lactating dairy cows. J Dairy Sci, 81, 2139–44.
  • Pursley JR, Wiltbank MC, Stevenson JS, Ottobre JS, Garverick HA, Anderson LL (1997): Pregnancy rates per artificial insemination for cows and heifers inseminated at a synchronized ovulation or synchronized estrus. J Dairy Sci, 80, 295–300.
  • Rantala MH, Katila T, Taponen J (2009): Effect of time interval between prostaglandin F(2alpha] and GnRH treatments on occurrence of short estrous cycles in cyclic dairy heifers and cows. Theriogenology, 71, 930–8.
  • Rivera H, Lopez H, Fricke PM (2004): Fertility of holstein dairy heifers after synchronization of ovulation and timed AI or AI after removed tail chalk. J Dairy Sci, 87, 2051–61.
  • Rivera H, Lopez H, Fricke PM (2005): Use of intravaginal progesteronereleasing inserts in a synchronization protocol before timed AI and for synchronizing return to estrus in Holstein heifers. J Dairy Sci, 88, 957–8.
  • Rivera H, Sterry RA, Fricke PM (2006): Presynchronization with gonadotropin-releasing hormone does not improve fertility in Holstein heifers. J Dairy Sci, 89, 3810–16.
  • Sâ Filho OG, Vilela ER, Geary TW, Vasconcelos JL (2009): Strategies to improve fertility in postpartum multiparous Bos indicus cows submitted to a fixed-time insemination protocol with gonadotropin-releasing hormone and prostaglandin F2alpha.. J Anim Sci, 87, 2806–14.
  • Sartori R Fricke PM, Ferreira JC, Ginther OJ, Wiltbank MC (2001): Follicular deviation and acquisition of ovulatory capacity in bovine follicles. Biol Reprod, 65, 1403–09.
  • Schafer DJ, Busch DC, Smith MF, Patterson DJ (2006): Characterization of follicular dynamics, timing of estrus, and response to GnRH and PG in replacement beef heifers after presynchronization with a 14-day CIDR. J Anim Sci, 84, (Suppl. 1): 49.
  • Souza AH, Gumen A, Silva EPB, Cunha AP, Guenther JN, Peto CM,Caraviello DZ and Wiltbank MC (2007): Supplementation with estradiol-17p before the last gonadotropin-releasing hormone injection of the ovsynch protocol in lactating dairy cows. J Dairy Sci, 90, 4623–34.
  • Stevenson JS, Smith JF, Hawkins DE (2000): Reproductive outcomes for dairy heifers treated with combinations of prostaglandin F2a, norgestomet, and gonadotropin-releasing hormone. J Dairy Sci, 83, 2008– 15.
  • Thompson KE, Stevenson JS, Lamb GC, Grieger DM, Loest CA (1999): follicular, hormonal, and pregnancy responses of early postpartum suckled beef cows to GnRH, norgestomet, and PGF. J Anim Sci, 77, 1823–32.
  • Vasconcelos JLM, Silcox RW, Rosa GJM, Pursley JR, Wiltbank MC (1999): Synchronization rate, size of the ovulatory follicle, and pregnancy rate after synchronization of oviilation beginning on different days of the estrous cycle in lactating dairy cows. Theriogenology, 52, 1067–78.
  • Wolfenson D, Inbar G, Roth Z, Kaim M, Bloch A, Braw-Tal R (2004): Follicular dynamics and concentrations of steroids and gonadotropin in lactating cows and nulliparoits heifers. Theriogenology, 62, 1042– 55.
  • Xu ZZ, Burton LJ, Macmillan KL (1996): Reproductive performance of lactating dairy cows following oestrus synchronisation with progesterone, oestradiol andprostaglandin. NZ Vet J, 44, 99–104.
  • Xu ZZ, Burton LJ (2000): Estrus synchronization of lactating dairy cows with GnRH, progesterone, and prostaglandin F2 alpha. J Dairy Sci, 83, 471–6. Geliş tarihi: 18.10.2010 / Kabul tarihi: 04.11.2010 Address for correspondence: DVM, PhD Umut Taşdemir, Lalahan Livestock Central Research Institute, 06852 e-mail: tasdemiru@gmail.com
There are 44 citations in total.

Details

Primary Language English
Subjects Veterinary Surgery
Other ID JA34YK88RV
Journal Section Research Article
Authors

Umut Taşdemir

Gülnaz Yilmazbaş Mecitoğlu

Abdulkadir Keskin

Ebru Karakaya

Yakup Çelik

Aydın Güzeloğlu

Ahmet Gümen

Publication Date June 1, 2011
Published in Issue Year 2011Volume: 58 Issue: 2

Cite

APA Taşdemir, U., Mecitoğlu, G. Y., Keskin, A., Karakaya, E., et al. (2011). Conception rate following timed artificial insemination protocols in dairy heifers synchronised by PGF2α and GnRH. Ankara Üniversitesi Veteriner Fakültesi Dergisi, 58(2), 135-139. https://doi.org/10.1501/Vetfak_0000002463
AMA Taşdemir U, Mecitoğlu GY, Keskin A, Karakaya E, Çelik Y, Güzeloğlu A, Gümen A. Conception rate following timed artificial insemination protocols in dairy heifers synchronised by PGF2α and GnRH. Ankara Univ Vet Fak Derg. June 2011;58(2):135-139. doi:10.1501/Vetfak_0000002463
Chicago Taşdemir, Umut, Gülnaz Yilmazbaş Mecitoğlu, Abdulkadir Keskin, Ebru Karakaya, Yakup Çelik, Aydın Güzeloğlu, and Ahmet Gümen. “Conception Rate Following Timed Artificial Insemination Protocols in Dairy Heifers Synchronised by PGF2α and GnRH”. Ankara Üniversitesi Veteriner Fakültesi Dergisi 58, no. 2 (June 2011): 135-39. https://doi.org/10.1501/Vetfak_0000002463.
EndNote Taşdemir U, Mecitoğlu GY, Keskin A, Karakaya E, Çelik Y, Güzeloğlu A, Gümen A (June 1, 2011) Conception rate following timed artificial insemination protocols in dairy heifers synchronised by PGF2α and GnRH. Ankara Üniversitesi Veteriner Fakültesi Dergisi 58 2 135–139.
IEEE U. Taşdemir, “Conception rate following timed artificial insemination protocols in dairy heifers synchronised by PGF2α and GnRH”, Ankara Univ Vet Fak Derg, vol. 58, no. 2, pp. 135–139, 2011, doi: 10.1501/Vetfak_0000002463.
ISNAD Taşdemir, Umut et al. “Conception Rate Following Timed Artificial Insemination Protocols in Dairy Heifers Synchronised by PGF2α and GnRH”. Ankara Üniversitesi Veteriner Fakültesi Dergisi 58/2 (June 2011), 135-139. https://doi.org/10.1501/Vetfak_0000002463.
JAMA Taşdemir U, Mecitoğlu GY, Keskin A, Karakaya E, Çelik Y, Güzeloğlu A, Gümen A. Conception rate following timed artificial insemination protocols in dairy heifers synchronised by PGF2α and GnRH. Ankara Univ Vet Fak Derg. 2011;58:135–139.
MLA Taşdemir, Umut et al. “Conception Rate Following Timed Artificial Insemination Protocols in Dairy Heifers Synchronised by PGF2α and GnRH”. Ankara Üniversitesi Veteriner Fakültesi Dergisi, vol. 58, no. 2, 2011, pp. 135-9, doi:10.1501/Vetfak_0000002463.
Vancouver Taşdemir U, Mecitoğlu GY, Keskin A, Karakaya E, Çelik Y, Güzeloğlu A, Gümen A. Conception rate following timed artificial insemination protocols in dairy heifers synchronised by PGF2α and GnRH. Ankara Univ Vet Fak Derg. 2011;58(2):135-9.