402 SUPEROVULATION OF TROPICAL-ADAPTED BOS TAURUS AND BOS INDICUS COWS IN A TROPICAL ENVIRONMENT

2010 ◽  
Vol 22 (1) ◽  
pp. 357
Author(s):  
R. H. Alvarez ◽  
A. C. Martinez ◽  
R. M. L. Pires
Keyword(s):  
Ovarian Function ◽  
Bos Taurus ◽  
Animal Health ◽  
Bos Indicus ◽  
Ovarian Response ◽  
Estradiol Benzoate ◽  
Maximum Temperature ◽  
Embryo Production ◽  
Chi Square ◽  
Average Maximum

Breed differences in ovarian function were found among beef Bos indicus and Bos taurus cows maintained in a subtropical environment (Alvarez P et al. 2000 J. Anim. Sci. 78, 1291-1302). The aim of this study was to compare ovarian response to superovulation and embryo production of tropical-adapted Bos taurus and Bos indicus cows. The experiment was carried out in a tropical wet climate at the experimental station of Instituto de Zootecnia (latitude 22°46′S, longitude 47°17′W) from November to February (average maximum temperature = 30.0 ± 0.8°C and average absolute precipitation = 153.1 ± 78.8 mm3). Forty Caracu (a local Bos taurus breed) and 50 Nelore (Bos indicus breed) lactating cows were treated with an intravaginal device containing progesterone (1.38 mg; CIDR-B®, Pfizer Animal Health, Montreal, Québec, Canada) and 2.5 mg i.m. of estradiol benzoate (Estrogin®, Farmavet, São Paulo, Brazil). Four days later, the animals were superovulated with multiple i.m. injections of 400 IU of FSH (Pluset®, Calier, Spain) in decreasing doses (75-75, 75-50, 50-25, and 25-25 IU) at 12-h intervals over 4 days. The CIDR-B® device was removed 3 days after the first superovulatory injection and cows received i.m. 150 μg of cloprostenol (Veteglan®, Calier, Spain). Cows were inseminated 48 and 62 h after the cloprostenol injection and embryos were recovered nonsurgically 7 days after insemination. Differences in the number of CL (assessed by ultrasound scanning), total number of ova/embryos, and number of transferable embryos were analyzed by ANOVA. Differences in the number of animals with low response (<3 CL) to superovulation were analyzed by chi-square test. All donors (with the exception of 1 Caracu and 2 Nelore) with ovarian response >3 CL showed estrus at insemination. Three (8.9%) Caracu and 5 (10.0%) Nelore cows had <3 CL following the superovulation treatment (P = 0.68). There was no difference (P > 0.05) in the mean (± SEM) CL counts of Caracu (11.4 ± 3.3) and Nelore (12.0 ± 4.1) cows. Similarly, there were no differences (P > 0.05) between Caracu and Nelore cows for total number of ova/embryos collected (8.6 ± 2.6 v. 9.0 ± 4.3) or transferable embryos (6.0 ± 2.4 v. 5.1 ± 2.9). In conclusion, the superovulation of Caracu and Nelore cows carried out in a tropical climate resulted in similar ovarian responses and embryo production. Supported by FAPESP.

251 FOLLICLE DEVIATION AND OVULATORY CAPACITY IN BOS INDICUS HEIFERS

2007 ◽  
Vol 19 (1) ◽  
pp. 242 ◽  
Author(s):  
L. U. Gimenes ◽  
N. A. T. Carvalho ◽  
M. F. Sá Filho ◽  
H. Ayres ◽  
J. R. S. Torres-Júnior ◽  
...  
Keyword(s):  
Bos Taurus ◽  
Animal Health ◽  
Bos Indicus ◽  
Estradiol Benzoate ◽  
Transrectal Ultrasonography ◽  
Holstein Cows ◽  
Second Phase ◽  
Chi Square ◽  
Follicle Diameter ◽  
Two Phases

In Holstein cows, the diameter of the dominant follicle (DF) at the time of follicle deviation is 8.5 mm and the subordinate follicle (SF) is 7.2 mm (Ginther et al. 1996 Biol. Reprod. 55, 1187–1194). However, follicular responsiveness to an ovulatory treatment occurs only with 10.0-mm-diameter follicles (Sartori et al. 2001 Biol. Reprod. 65, 1403–1409). The current study tested the hypothesis that, in Bos indicus (Nelore and crossbred Nelore � Gir) females, the follicular diameters at the time of deviation and ovulation responsiveness are smaller than those in Holstein cows. The experiment was performed in two phases. In the first phase, 12 Nelore heifers were previously synchronized with a protocol using progestagen and estradiol benzoate. After implant removal, all heifers were evaluated by transrectal ultrasonography (Aloka SSD-500, Tokyo, Japan) every 12 h until Day 5 of the estrous cycle (Day 0 = Day of the ovulation) to assess the time of ovulation, the time of follicle deviation, and the follicular diameter at the deviation. In the second phase, 29 Bos indicus heifers (Nelore and crossbred Nelore � Gir) were previously synchronized with the same protocol as cited above. After the ovulations (Day 0), the follicles were evaluated by transrectal ultrasonography every 24 h, until they reached the diameter of 7.0–8.4 mm (n = 9); 8.5–10.0 mm (n = 10); and &gt;10.0 mm (n = 10). In order to assess the ovulatory capacity, all animals were treated with 25 mg of LH (Lutropin-V�; Bioniche Animal Health, Inc., Belleville, Ontario, Canada) at these follicle diameter ranges. After the LH treatment, all animals were monitored by ultrasonography every 12 h for 48 h. ANOVA, Bartlett, and chi-square tests were used in the statistical analyses. In the first phase, the diameters of the DF and SF at the time of follicular deviation (61.9 � 4.9 h after ovulation) were 6.2 � 0.2 and 5.8 � 0.2 mm, respectively. In the second phase, the the average follicular diameters at the time of LH administration in the groups 7.0–8.4 mm, 8.5–10.0 mm, and &gt;10.0 mm were 7.6a � 0.1 mm, 9.6b � 0.1 mm, and 10.9c � 0.2 mm; and their ovulation rates were 33.3%a (3/9), 80.0%b (8/10), and 90.0%b (9/10), respectively (P &lt; 0.05). The interval from LH treatment to ovulation was 38.0 � 4.0 h, 31.5 � 2.7 h, and 30.0 � 2.0 h, respectively (P &gt; 0.05). In conclusion, in Bos indicus heifers, follicle deviation occurred with smaller diameters than previously reported in Bos taurus breeds. In addition, Bos indicus heifers are able to ovulate in response to 25 mg of LH with smaller diameters compared to those of Bos taurus breeds. Moreover, in Bos indicus heifers, ovulatory capacity is acquired by follicles as small as 7.0–8.4 mm, but this responsiveness significantly increases after follicles reach 8.5–10.0 mm. This work was supported by FAPESP (Proc:03/10203-4); Bioniche Animal Health, Inc., Belleville, Ontario, Canada; and Tecnopec, S�o Paulo, Brazil.

387 EFFECT OF NUMBER OF INSEMINATIONS ON EMBRYO PRODUCTION IN SUPERSTIMULATED NELORE (BOS INDICUS) COWS SUBJECTED TO FIXED-TIME ARTIFICIAL INSEMINATION

2007 ◽  
Vol 19 (1) ◽  
pp. 309
Author(s):  
C. M. Martins ◽  
H. Ayres ◽  
J. R. S. Torres-Junior ◽  
A. H. Souza ◽  
G. A. Bó ◽  
...  
Keyword(s):  
Animal Health ◽  
Bos Indicus ◽  
Fixed Time ◽  
Estradiol Benzoate ◽  
Ovulation Rate ◽  
Embryo Production ◽  
Chi Square ◽  
Chi Square Test ◽  
Level Of Significance ◽  
Ovulatory Follicles

In embryo transfer programs, 2 inseminations per superstimulated donor are usually recommended. Based on studies of follicular dynamics in Bos indicus donors (Baruselli et al. 2006 Theriogenology 65, 77–88), we tested the hypothesis that a single fixed-time AI (FTAI) at 16 h after pituitary luteinizing hormone (pLH) treatment is as efficacious as 2 FTAI at 12 and 24 h after the pLH treatment. Suckling Nelore cows (n = 10), 60 � 12 days postpartum, were equally distributed in 2 experimental groups: G-1TAI vs. G-2TAI, in a crossover design. All animals received an intravaginal progesterone device (DIB; Syntex S.A., Buenos Aires, Argentina) and 2 mg of estradiol benzoate (IM, Ric Be; Syntex) at random stages of the estrous cycle (Day 0). Superstimulatory treatments started on Day 4 with pFSH (133 mg; Folltropin-V; Bioniche Animal Health Canada, Inc., Belleville, Ontario, Canada) in 8 decreasing doses, given IM 12 h apart. On Day 6, all cows received 2 (AM and PM) treatments of 0.15 mg of d-cloprostenol (Prolise; Syntex). The DIB devices were removed 36 h after the first PGF2� injection. The pLH treatment (25 mg IM; Lutropin-V; Bioniche) was given 48 h after the first PGF2� treatment (12 h after the last pFSH treatment). In the G-2TAI group, all cows received 2 inseminations (12 and 24 h after the pLH). Cows in the G-1TAI group received a single insemination (16 h after the pLH). All inseminations were done with the same batch of semen from a single bull. Ultrasound examinations (PIE Medical Scanner 200; Pie Medical Equipment, Maastricht, The Netherlands) were performed every 12 h from 0 to 72 h after pLH treatment to evaluate the number of ovulatory follicles (&lt;8 mm), the ovulation rate, and the time of ovulation. Variables were analyzed by ANOVA and chi-square test. The homogeneity of the variances (distribution of ovulations) was analyzed by Bartlett&apos;s test. Conclusions were based on a 5% level of significance. The results for G-1TAI and G-2TAI were, respectively: number of follicles &gt;8 mm at the time of pLH administration (16.2 � 1.4 vs. 14.8 � 1.2; P &gt; 0.05), ovulation rate (63.8 � 3.8% vs. 64.2 � 4.3%; P &gt; 0.05), interval from the first to the last ovulation (32.4 � 1.8 vs. 33.6 � 1.6 h; P &gt; 0.05), total ova/embryos (8.2 � 0.9 vs. 7.2 � 0.8; P &gt; 0.05), Grade 1 embryos (2.0 � 0.5 vs. 2.3 � 0.4; P &gt; 0.05), transferable embryos (Grades 1, 2, and 3) (4.3 � 0.7 vs. 4.2 � 0.6; P &gt; 0.05), freezable embryos (Grades 1 and 2) (2.9 � 0.6 vs. 2.8 � 0.4; P &gt; 0.05), unfertilized ova (0.6 � 0.2 vs. 0.8 � 0.2; P &gt; 0.05), and degenerated embryos (3.3 � 0.9 vs. 2.2 � 0.3; P &gt; 0.05). These results suggest no significant differences in embryo production between superstimulated Nelore donors inseminated once or twice by fixed time following administration of pLH. This work was supported by Tecnopec, Brazil.

225 ADDITION OF EQUINE CHORIONIC GONADOTROPIN TO A TRADITIONAL FOLLICLE STIMULATING HORMONE PROTOCOL FOR SUPEROVULATION OF BOS TAURUS BEEF COWS

2012 ◽  
Vol 24 (1) ◽  
pp. 224 ◽  
Author(s):  
R. L. Davis ◽  
A. Arteaga ◽  
J. F. Hasler
Keyword(s):  
Treatment Group ◽  
South America ◽  
Bos Taurus ◽  
Animal Health ◽  
Bos Indicus ◽  
Treatment Protocol ◽  
Beef Cows ◽  
High Response Rate ◽  
Control Group ◽  
Embryo Production

This study examined the superovulatory responses of Bos taurus beef cows maintained in a commercial embryo transfer facility. Donors were superovulated 1 to 3 times each with either a traditional 8 injection FSH protocol (controls, n = 126) or 6 injections of FSH with the seventh or eighth FSH treatments replaced by 2 injections of eCG (treatment, n = 134). During the 5-month study, 132 donors were alternatively assigned to a control or treatment group for a single superovulation and an additional 62 animals were superovulated 2 (n = 58) or 3 times (n = 4) in a crossover design. Although 14 beef breeds were represented in the study, 87% of the cows were Angus, Red Angus, Polled Hereford, or Charolais. All donors were synchronized on Day 0 with a CIDR, 5 mg of oestradiol-17β and 100 mg of progesterone. Starting on Day 4 (p.m.), controls were injected twice daily for 4 days with descending doses of porcine FSH (Folltropin-V®, Bioniche Animal Health, Belleville, Ontario, Canada). Cows received 750 μg of cloprostenol (Estrumate®, Intervet Schering-Plough, Summit, NJ, USA) at the seventh FSH injection and the CIDR was removed at the eighth FSH injection. Based on previous experience with specific, individual animals, total FSH dose per donor ranged from 240 to 400 mg. However, 74% of treatments involved 380 mg for controls and 310 mg for treated donors that received eCG. In addition, donors that were superovulated more than once received the same FSH dose in the crossover, treatment-control design. In the treatment group, 200 IU of eCG (Pregnecol™ 6000, Bioniche Animal Health) was substituted for the seventh and eighth FSH injections. Inseminations were conducted on a timed AI basis, with one unit of semen 32 h and a second 48 h following CIDR removal. Results were analysed by ANOVA as shown in Table 1. Although more ova/embryos and unfertilized ova (UFO) were recovered in the control group, the control and treatment groups did not differ in the number of grade 1, 2, or 3 embryos or in the number of degenerate embryos. Previous superovulation studies in South America using eCG to replace the last 2 injections of FSH resulted in more total ova/embryos in Nelore cows but not heifers and in more embryos in Brangus and Sindhi cows. The mean embryo production for the control cows in this study was high and the addition of eCG in the protocol did not improve embryo production. Failure of eCG to increase the number of embryos for Bos taurus cows in this study compared with previous studies may be due to differences with Bos taurus versus Bos indicus breeds or differences in management factors between Canada and South America. The high response rate in the controls may also have contributed to the failure of any advantage of adding eCG to the treatment protocol. Table 1.Mean numbers (± SEM) of ova and embryos recovered from Bos taurus females superovulated with 2 different protocols

144 HEAT TOLERANCE OF DEMI-EMBRYOS FROM A TROPICAL-ADAPTED BOS TAURUS BREED

2011 ◽  
Vol 23 (1) ◽  
pp. 176
Author(s):  
R. H. Alvarez ◽  
A. C. Martinez ◽  
R. M. L. Pires
Keyword(s):  
Bos Taurus ◽  
Blastocyst Stage ◽  
Maximum Temperature ◽  
Chi Square ◽  
Average Maximum ◽  
Significant Difference ◽  
Long Time ◽  
Chi Square Test ◽  
Uterine Flushing ◽  
Wet Climate

Long-time selection of autochthonous Bos taurus breeds in a tropical environment is known to result in some physiological changes, including gamete thermotolerance. The aim of this study was to evaluate the resistance to heat shock (HS) of demi-embryos from tropical-adapted B. taurus cattle. The experiment was carried out in a tropical wet climate, at the experimental station of Instituto de Zootecnia (latitude 22°46′S; longitude 47°17′W) from November to February (average maximum temperature = 30.0 ± 0.8°C, and average absolute precipitation = 153.1 ± 78.8 mm3). Embryos (morulae) from 37 superovulated Caracu (a local B. taurus breed) cows were collected by uterine flushing on Day 6 after AI. Sixty-two grade I morulae were split with a metal microblade coupled to a micromanipulator, and each demi-embryo was placed separately in a 35-μL drop of culture medium [SOF supplemented with modified Eagle medium amino acids, sodium citrate, myo-inositol (SOFaaci), and 10% FCS] under mineral oil in a humidified atmosphere of 5% CO2, at 38.5°C for 24 h (control) or at 41°C for 12 h and a further 12 h at 38.5°C (HS). Halves of morulae that developed to the blastocyst stage (showing a central cavity) after a 24-h culture were transferred to recipient heifers previously synchronized with the donors. Pregnancy was monitored by ultrasound scanning 40 days after transfer, and data were analysed by chi-square test. There was a significant difference in the development to the blastocyst stage between control (44/62, 71.0%) and HS (30/62, 48.4%) demi-embryos (P < 0.01). Pregnancy rate obtained from control (14/44, 31.8%) and HS (8/30, 26.7%) blastocysts was not different (P > 0.05). We conclude that HS affected embryonic development from the morulae to blastocyst stage of cultivated demi-embryos, although fertility of blastocysts that survived to HS was not further compromised. Further studies are necessary to elucidate whether Caracu embryos are more thermotolerant than other tropically sensitive B. taurus breeds. Supported by FAPESP.

scholarly journals GnRH or estradiol benzoate combination with CIDR improves in-vivo embryo production in bovines (Bos indicus and Bos taurus) under subtropics

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12077
Author(s):  
Khalid Mahmood ◽  
Muhammad Zahid Tahir ◽  
Mahboob Ahmad Butt ◽  
Shazia Mansoor Qureshi ◽  
Amjad Riaz
Keyword(s):  
Bos Taurus ◽  
Bos Indicus ◽  
Estradiol Benzoate ◽  
Limiting Factors ◽  
Control Group ◽  
Corpora Lutea ◽  
Embryo Production ◽  
Varied Response ◽  
Donor Cows

Multiple Ovulation and Embryo Transfer (MOET) technology is a potential technique to upgrade livestock species’ genetics. The varied response to super-stimulatory treatments remains one of the limiting factors to this technology’s widespread use. The present study was aimed to improve the superovulation response and in-vivo embryo production by using controlled internal drug release (CIDR)-GnRH or CIDR-EB (Estradiol Benzoate) along with conventional superovulation protocol in Holstein Frisian (HF): Bos taurus; n = 42) and Crossbred (XB: Cholistani (Bos indicus) × HF; n = 28) cows. In the CIDR-GnRH/CIDR-EB treatment, CIDR was implanted in the cows after confirming the presence of a corpus luteum (CL) on the 8th day after estrus. 2 ml GnRH (Lecirelin acetate 0.0262 mg/ml) or 2 mg EB was also administered in CIDR-GnRH/CIDR-EB groups, respectively. Both groups were given super-stimulatory treatment from the 11th day after estrus (FSH in tapering doses twice a day for four consecutive days). On day 13, two doses of 2 ml prostaglandin (75 µg/ml of dextrorotatory cloprostenol) were administered (am: pm), and CIDR was removed the following day. Two artificial inseminations (AI) of the cows were performed (12 h apart) on the 15th day. No CIDR and GnRH/E.B were given in the control group, but the remaining superovulation protocol was the same. Later on, seven days after the first AI, non-surgical embryo flushing was done. The transferable embryos produced from three different superovulation protocols were then transferred into the recipient cows (n = 90) for determining their fertility. Statistical analysis revealed that the number of super-estrus follicles (SEF), multiple corpora lutea (MCL), ovulation/fertilization percentage, fertilized structures recovered (FSR), and transferable embryos (TEs) remained significantly higher (p < 0.05), and days taken for return to estrus (RTE) after embryo collection remained significantly lower (p < 0.05) in CIDR-GnRH (n = 18) and CIDR-EB (n = 15) groups as compared to the control (n = 37). The comparison between XB and HF cows revealed that the TEs production in CIDR-GnRH (XB = 5 vs HF = 13) and CIDR-EB (XB = 6 vs HF = 9) based superovulation protocols were 11.60  ±  4.08 vs 04.31  ±  0.98 and 09.33  ±  1.78 vs 05.22  ±  1.36, respectively. TEs production in XB cows (n = 5) of the CIDR-GnRH group was significantly higher (11.60  ±  4.08) than other groups. On the other hand, the days taken for RTE after embryo collection remained significantly lower (p < 0.05) in HF cows of treatment groups. However, the fertility of TEs was neither affected significantly (p > 0.05) by the superovulation protocol used nor by breed differences among donor cows. In conclusion, using CIDR-GnRH or CIDR-EB along with conventional superovulation protocol may enhance the efficiency of MOET programs in cattle. Furthermore, XB donor cows demonstrated a better performance than HF donor cows under subtropical conditions.

297 LACK OF IMPROVEMENT ON EMBRYO PRODUCTION BY THE REPLACEMENT OF THE LAST TWO DOSES OF pFSH BY eCG IN SUPERSTIMULATED NELORE HEIFERS

2009 ◽  
Vol 21 (1) ◽  
pp. 245 ◽  
Author(s):  
R. Sartori ◽  
M. M. Guardieiro ◽  
C. M. Barros ◽  
M. R. Bastos ◽  
G. M. Machado ◽  
...  
Keyword(s):  
New Zealand ◽  
Financial Support ◽  
Buenos Aires ◽  
Previous Experiment ◽  
Animal Health ◽  
Bos Indicus ◽  
Estradiol Benzoate ◽  
Embryo Production ◽  
Uterine Flushing ◽  
Paired T Test

Results from a previous experiment have shown that the replacement of pFSH by eCG on the last day of the superstimulatory treatment in Nelore (Bos indicus) cows resulted in a greater superovulatory (SOV) response as compared to the treatment exclusively with pFSH (Barros CM et al. 2008 Repr. Fertil. Dev. 20, 152 abst). The aim of this study was to investigate if a similar approach would be beneficial for embryo production in nulliparous Nelore heifers. Forty heifers were randomly divided into two SOV groups: FSH Group: eight pFSH injections or FSH-eCG Group: six pFSH injections followed by two eCG injections. Each female received both treatments 65 days apart in a cross-over design. The SOV protocols consisted of an IM injection of 2 mg estradiol benzoate (Estrogin, Farmavet, São Paulo, Brazil) and insertion of an intravaginal progesterone releasing device (1.9 g progesterone, CIDR, Pfizer, Hamilton, New Zealand) on Day 0. On Day 4.5, the superstimulatory treatments (70 mg pFSH; Folltropin-V, Bioniche Animal Health; Belleville, ON, Canada) were initiated and given in decreasing doses of 28, 21, 14, and 7 mg twice a day, over a 4-day period. The FSH-eCG Group had the last two doses of pFSH replaced by two doses of 150 IU eCG (Folligon, Bioniche). At the time of the fifth and sixth injections of FSH, 25 mg dinoprost tromethamine (Lutalyse, Pfizer, Paulinia, Brazil) was injected IM. The CIDR was removed at the time of the seventh superstimulatory injection. Ovulation was induced with an IM injection of 0.05 mg GnRH (gonadorelin acetate; Gestran Plus; ARSA S.R.L., Buenos Aires, Argentina) 12 h after the last superstimulatory injection. All heifers were artificially inseminated with frozen/thawed semen from the same bull 12 and 24 h after GnRH. Seven days after the first AI, embryos/ova were recovered using a nonsurgical uterine flushing technique and classified according to IETS standards. To determine the superstimulatory (number of follicles ≥6 mm 12 h prior to GnRH) and SOV (number of ovulated follicles 48 h after GnRH, confirmed by CL number at the time of embryo collection) responses, transrectal ultrasonography was performed. Data were analyzed by paired t test and are presented as mean ± SEM. There was no difference between FSH and FSH-eCG groups regarding superstimulatory (23.2 ± 1.9 v. 22.3 ± 1.6 follicles ≥6 mm, P = 0.56) or SOV (15.2 ± 1.1 v. 17.5 ± 1.4 CL, P = 0.21) responses. Treatments were also similar for number of total embryos/ova (9.6 ± 0.9 v. 9.5 ± 1.0, P = 0.91), viable embryos (4.9 ± 0.7 v. 3.7 ± 0.5, P = 0.17), or degenerate embryos (3.0 ± 0.6 v. 4.3 ± 0.7, P = 0.10) recovered. Contrasting with the results using Nelore cows, the present study did not observe improvement on embryo production by replacing of the last two doses of pFSH by eCG in superstimulated heifers. Financial support from CNPq, FAPESP, EMBRAPA and Pfizer of Brazil.

16 MODIFICATION TO INTRAVAGINAL PROGESTERONE + ESTRADIOL-BASED ESTROUS SYNCHRONIZATION PROTOCOLS TO IMPROVE OVARIAN RESPONSES IN BOS INDICUS HEIFERS

2010 ◽  
Vol 22 (1) ◽  
pp. 166
Author(s):  
S. A. A. Butler ◽  
N. J. Phillips ◽  
G. Boe-Hansen ◽  
G. A. Bó ◽  
B. M. Burns ◽  
...  
Keyword(s):  
Ovarian Function ◽  
Animal Health ◽  
Bos Indicus ◽  
Fixed Time ◽  
Estradiol Benzoate ◽  
Lower Amount ◽  
Estrous Synchronization ◽  
Follicle Diameter ◽  
Half Dose ◽  
Mate Removal

Estrous synchronization (ES) protocols for fixed-time AI (FTAI) have been mainly developed for Bos taurus cattle assuming that usage in Bos indicus cattle results in similar outcomes. Unexplained variation in the reproductive outcomes of these treatments in extensively managed Bos indicus herds has limited the adoption of FTAI. The aim was to evaluate the ovarian function in heifers treated with different doses of progesterone (P4). Brahman (n = 30) and Brahman-cross (n = 34; 3/4 to 7/8 Brahman) heifers weighing an average of 285 kg (248 to 323 kg) and 307 kg (250 to 363 kg), respectively, were allocated at random to 1 of 4 treatment groups: 1) full-dose Cue-Mate (CM100; two P4-impregnated pods, 1.56 g of P4; Bioniche Animal Health Aust/Asia, Armidale, NSW, Australia; n = 17); 2) half-dose Cue-Mate (CM50; one P4-impregnated pod; 0.78 g of P4; n = 15); 3) half-dose Cue-Mate + 300IU of eCG (CM50+G; Pregnecol, Bioniche Animal Health, Aust/Asia; n = 14) i.m. at Cue-Mate removal; and 4) double PGF2α group (PG; n = 18). Heifers in the P4-treated groups received 1 mg of EB (estradiol benzoate; Ciderol; 1 mg mL-1; Genetics Australia, Bacchus Marsh, Victoria) at Cue-Mate insertion (Day -10) and 24 h after Cue-Mate removal (Day -1) and 250 μg of PGF2α (Cloprostenol, Estromil, Ilium Veterinary Products, Smithfield, Australia) i.m. at Cue-Mate insertion (Day -10) and removal (Day -2). Heifers in the PG group received 500 μg of PGF2α on Day -16 and Day -2 i.m. Ovarian function was evaluated twice daily by transrectal ultrasonography on Day -1, Day 0 (expected estrus), and Day 1, and once daily on Days 4, 6, 8, 10, 12, and 16 of the synchronized and return cycles. Concurrent blood samples were collected to determine plasma P4 concentrations. A one-way ANOVA was used to analyze follicle diameter variables and Fisher’s Exact test was used to analyze all other data reported (StataCorp 2007, College Station, TX, USA). There was no difference (P = 0.31) in the diameter of the dominant follicle 54 to 56 h post-Cue-Mate removal (the time FTAI would be conducted) in the CM100 (11.5 ± 1.1), CM50 (13.3 ± 1.5), CM50+G (13.7 ± 1.5), or PG (14.5 ± 0.7) groups. Synchrony of ovulation in ovulating heifers did not differ (P < 0.05) between the P4-treated groups with 12/13 (CM100), 11/12 (CM50), and 9/12 (CM50+G) heifers ovulating within 53 to 77 h after Cue-Mate removal, but was lower (P < 0.02) for the PG group (1/5). Individual heifer P4 profiles revealed that 2/15, 1/15, 3/12, and 0/5 of heifers that ovulated in the CM100, CM50, CM50+G, andPG groups, respectively, failed to re-ovulate in the return cycle. Also, 1/15, 3/15, 1/12, and 0/5 of heifers that ovulated in the CM100, CM50, CM50+G, and PG groups, respectively, developed a CL that persisted into the return cycle. This study shows the potential benefits of using intravaginal devices containing a lower amount of P4 to induce synchronized ovulation in Brahman heifers, consistent with the findings of Carvalho et al. (2008 Theriogenology 69, 167).

scholarly journals 243 PREGNANCY RATES IN THE FIELD AFTER THE TRANSFER OF BOVINE IVP EMBRYOS VITRIFIED BY THE CRYOLOGIC VITRIFICATION METHOD

2005 ◽  
Vol 17 (2) ◽  
pp. 272 ◽  
Author(s):  
R. Fry ◽  
C. Earl ◽  
K. Fry ◽  
W. Lindemans
Keyword(s):  
Large Scale ◽  
Bos Taurus ◽  
Bos Indicus ◽  
Pregnancy Rates ◽  
Chi Square ◽  
Full Field ◽  
Transfer Programs ◽  
Short Period ◽  
Rectal Palpation ◽  
User Friendly

Although large numbers of IVP embryos can be produced from donor cattle in a short period of time, commercial acceptance of the technology depends on the ability to cryopreserve these embryos and achieve a 50% pregnancy rate in large-scale embryo transfer programs. Many studies have reported low pregnancy rates of about 20% after the transfer of cryopreserved IVP embryos. We have developed the user friendly CryoLogic Vitrification Method (CVM) that vitrifies embryos on a solid surface at −196°C and warms them rapidly in a one-step procedure prior to transfer (Lindemans et al. 2004 Reprod. Fertil. Dev. 16, 174). We present an overview of the pregnancy rates in the field after vitrification of bovine IVP embryos by the CVM. The bos taurus IVP embryos in southern Australia (bT) and the bos indicus-based IVP embryos in northern Australia (bI) were produced by our standard TVR and IVP methodology (Fry et al., 2003 Theriogenology 59, 446). Pregnancy was determined by rectal palpation between Day 40 and Day 90 and differences between treatments were analyzed by chi-square. The development of the CVM has enabled the successful cryopreservation of bovine IVP embryos. In the laboratory the typical survival (90% re-expansion) and development (80% hatching) of IVP embryos post-vitrification is high and, as demonstrated here, the pregnancy rates after transfer are approaching commercially acceptable levels. However, further research is required to identify factors that may influence success under full field conditions, for both the IVP and the vitrification technologies. Table 1. Pregnancy rates for fresh IVP, CVM-vitrified IVP, and traditionally flushed embryos cryopreserved in glycerol

Embryo production in middle-aged and mature Bos taurus × Bos indicus cows induced to multiple ovulation in a tropical environment

2019 ◽  
Vol 51 (8) ◽  
pp. 2641-2644
Author(s):  
Fernando Naranjo-Chacón ◽  
Felipe Montiel-Palacios ◽  
Rodolfo Canseco-Sedano ◽  
Concepción Ahuja-Aguirre
Keyword(s):  
Bos Taurus ◽  
Bos Indicus ◽  
Tropical Environment ◽  
Middle Aged ◽  
Embryo Production ◽  
Multiple Ovulation

287 EFFECT OF FOLLICULAR WAVE SYNCHRONIZATION AND ABSENCE OF CORPUS LUTEUM ON COC RECOVERY IN Gyr (BOS TAURUS INDICUS) COWS

2010 ◽  
Vol 22 (1) ◽  
pp. 300
Author(s):  
T. Miyauchi ◽  
C. A. C. Fernandes ◽  
E. R. Oliveira ◽  
B. F. L. Alves ◽  
J. H. M. Viana
Keyword(s):  
Bos Taurus ◽  
Animal Health ◽  
Cumulus Cell ◽  
Estradiol Benzoate ◽  
Corpora Lutea ◽  
Portable Ultrasound ◽  
Follicular Wave ◽  
Main Technique ◽  
Oocyte Donors

Transvaginal guided follicle aspiration (TGFA) is the main technique used in Brazil to recover oocytes for in vitro embryo production (IVP) in bovine. Different protocols have been proposed to synchronize follicular emergence in oocyte donors, but most of them were developed for use in European breeds of cattle, which show many differences in ovarian physiology when compared with Zebu breeds. The aim of this study was to compare different protocols for preparation of Gyr (dairy zebu breed) oocyte donors. The TGFA were performed in a donor management facility located in Minas Gerais State, southeast Brazil. Pluriparous cycling Gir cows (n = 42) were used as donors. All cows underwent 3 treatments: G1 (control), no treatment before TGFA; G2, 2 mg of estradiol benzoate (EB) for follicular wave synchronization given i.m. 5 days before TGFA; and G3, norgestomet auricular implants given 9 days and 2 mg of EB plus 0.53 mg of cloprostenol given 5 days before TGFA. The interval between TGFA in the same donor was greater than 30 days. All procedures were made by the same technician, using a portable ultrasound device, disposable 19G or 20G needles, and a vacuum pressure of 80 mm Hg. The aspirated follicular fluid was collected in 50-mL Falcon tubes and sent to the laboratory for COC identification and classification under 50 × magnification. Recovered oocytes were classified according to cumulus cell layers and cytoplasm morphology. The total number of oocytes and viable COC recovered and the procedure length (min), including time spent for TGFA and laboratory manipulation, were compared. Data were evaluated by ANOVA, and means compared by Tukey’s test. A total of 126 TGFA sessions were performed, with recovery of 2,809 oocytes (20.31 ± 12.32 of COC and 14.83 ± 7.97 of viable COC per cow/session; mean ± SD). The total number of recovered oocytes and viable COC recovered were lower in G1 compared with G2 and G3 (15.18 ± 11.07 v. 21.18 ± 9.71 and 24.68 ± 9.03; and 9.53 ± 7.22 v. 16.97 ± 6.47 and 18.84 ± 8.90, respectively; P < 0.05) There was no difference (P > 0.05) between G2 and G3 on the number of oocytes or viable COCs recovered. The procedure length, however, was longer in G1 and G2 compared with G3 (49.6 ± 15.1 and 46.9 ± 13.4 v. 35.8 ± 13.1 min, respectively; P < 0.05) The shorter procedure length in G3 was probably associated with the reduced number of cows showing no corpora lutea (38/42, 90%), which resulted in reduction of bleeding and clot formation in the aspirated fluid. These results show that (1) previous follicular wave synchronization by EB can improve the number and quality of recovered oocytes; (2) the absence of corpora lutea does not increase the number of recovered COC and viable COC, but reduces the time spent in the procedure. Intervet Schering Plough Animal Health.

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