11 CALF REMOVAL IMPROVES CO-SYNCH + CONTROLLED INTERNAL DRUG-RELEASE PREGNANCY RATES IN BEEF COWS

2009 ◽  
Vol 21 (1) ◽  
pp. 105 ◽  
Author(s):  
D. J. Kesler ◽  
D. B. Faulkner ◽  
F. A. Ireland ◽  
J. Dahlquist ◽  
S. Z. El-Zarkouny ◽  
...  
Keyword(s):  
Treatment Group ◽  
Pregnancy Rate ◽  
Estrous Cycle ◽  
Beef Cows ◽  
Pregnancy Rates ◽  
Control Treatment ◽  
Control Group ◽  
Research Station ◽  
Treatment Groups ◽  
Calf Removal

Improving AI pregnancy rates in beef cattle will enhance the profitability of beef herds during these current times of increasing cost inputs by enhancing the quality of the calf crop. This experiment was aimed at determining the effect of calf removal (from CIDR removal to timed AI) during estrous cycle synchronization on AI pregnancy rates. This experiment was conduced at the Dixon Springs Research Station (Simpson, IL) during the fall 2007 breeding season. The beef cows used for this research project were crossbred Angus cows between 2 and 8 years of age that had calved in August to October of 2007. Cows were at least 45 days postpartum at the timed AI (November 2007). All cows were randomly divided into 1 of 2 treatment groups: cows in treatment group 1 (control group, n = 284) were allowed to keep their calves for the entire estrous cycle synchronization and AI program (except during brief times of treatment administration), whereas cows allotted to treatment group 2 (n = 258) had their calves removed at the time of CIDR implant removal/PGF2α treatment and returned following AI. The calves were maintained on creep feed out of sight and sound of their dams. All cows were synchronized by using the CO-Synch + CIDR protocol [CIDR (1.38 g) + GnRH (100 μg) on Day 0 and CIDR removal on Day 7 + PGF2α (25 mg)] and were inseminated at a predetermined time of 60 to 66 h post PGF2α with semen from proven bulls. At AI, cows also received an injection of GnRH (100 μg). All cows were pregnancy checked 50 to 65 days after timed AI via ultrasonography. Statistical comparisons were performed by using the chi-square test of SAS. The pregnancy rate for cows in the control treatment group was 47% (132 of 284) and was 57% (147 of 258) for the calf-removal treatment group. There was a significant increase in pregnancy rate in the treatment group (P < 0.02) that resulted in 10 more calves per 100 synchronized AI breedings. Although excellent facilities are needed to maintain calves away from their dams during this 60 to 66 h and there are additional costs for the feedings required for the calves, there is a savings in time (one calf separation from the cow is eliminated). In conclusion, removing the calves at the onset of estrous cycle synchronization can improve pregnancy rates to synchronized timed AI and can increase the ease of cattle handling during this process by reducing the number of calf removals during routine cow workings. Table 1.Pregnancy rates to single synchronized timed AI for control and calf removal treatment groups

10 INFLUENCE OF ADMINISTRATION OF HUMAN CHORIONIC GONADOTROPIN ON DAY 4 AFTER FIXED-TIME AI ON CORPUS LUTEUM SIZE, FUNCTION, AND PREGNANCY RATE IN BEEF COWS

2014 ◽  
Vol 26 (1) ◽  
pp. 119
Author(s):  
J. B. S. Borges ◽  
D. X. Thedy
Keyword(s):  
Corpus Luteum ◽  
Pregnancy Rate ◽  
Fixed Time ◽  
Beef Cows ◽  
Pregnancy Rates ◽  
Control Group ◽  
Chi Square ◽  
Prostaglandin F2a ◽  
Successful Establishment ◽  
Early Rise

Successful establishment of pregnancy in the cow depends on early rise of progesterone (P4) to improve embryo development. The present study was carried out to determine the corpus luteum (CL) function and pregnancy rate following the administration of 1.500 IU of hCG in suckled beef cows on Day 4 after fixed-time AI (FTAI). Crossbred Angus cows (n = 429), 40 to 70 days postpartum, were synchronized using 2 mg of oestradiol benzoate (EB) i.m. and an intravaginal progesterone-releasing device containing 1 g of P4 for 7 days. At device removal, prostaglandin F2a (150 mg of D-cloprostenol) was injected i.m.; 24 h later, 1 mg of EB was given and the FTAI were done 30 to 36 h after EB using semen of just 1 bull. Cows were assigned alternatively to receive 1.500 IU of hCG i.m. (n = 200) or 1 mL of saline i.m. (n = 229) on Day 4 after FTAI. Ovaries were examined by transrectal ultrasonography (n = 71) on Days 4 and 7 to detect the presence and to measure the area of CL. Blood samples were collected on Days 4, 7, 10, 14, and 30 post-oestrus to determine P4 concentration by RIA. Pregnancy diagnoses were done 30 days after FTAI. The effects of treatments on CL area and serum P4 levels were analysed by ANOVA (Proc GLM, SAS Institute Inc., Cary, NC, USA) and pregnancy rates compared by chi-square (Proc CATMOT, SAS). The induction of accessory CL determined on Day 7 was 44% in cows treated with hCG and not observed in the control group. The area of the CL on Day 7 was significantly higher (P < 0.01; 3.37 ± 2.56 v. 2.56 ± 0.22 cm2) in the hCG group. Despite the increase in CL size, the mean levels of P4 on Days 4, 7, 10, 14, and 30 post-AI indicated no difference (P > 0.05) in CL function between control and hCG-treated cows. On Day 30, pregnancy rates were not different (P = 0.08), at 46.7 and 55% for control and hCG-treated cows, respectively. In conclusion, administration of 1.500 IU of hCG on Day 4 post-FTAI did not improve pregnancy rate in suckled beef cows.

9 EFFECT OF TIMING OF INSEMINATION WITH SORTED SEMEN ON SUBSEQUENT PREGNANCY RATE IN POSTPARTUM BEEF COWS SYNCHRONIZED WITH A MODIFIED 14-DAY PROGESTERONE PROTOCOL

2014 ◽  
Vol 26 (1) ◽  
pp. 119
Author(s):  
A. J. Davis ◽  
J. G. Powell ◽  
T. D. Lester ◽  
R. W. Rorie
Keyword(s):  
Pregnancy Rate ◽  
Animal Health ◽  
Prostaglandin F2α ◽  
Beef Cows ◽  
Subsequent Pregnancy ◽  
Pregnancy Rates ◽  
Treatment Groups ◽  
Rate Analysis ◽  
Chi Squared ◽  
Pregnancy Status

A study investigated the effect of AI timing on pregnancy rate when using X sorted semen, and whether prostaglandin F2α (PGF2) injection on Day 7 of a modified 14-day progesterone (P4) protocol improved oestrous response in beef cows. Angus-based cows were allotted across treatment groups by cyclicity, parity, weight, body condition, and days postpartum. Treatment 1 (n = 132) cows received a CIDR P4 insert (Eazi-Breed CIDR, Pfizer Animal Health, Groton, CT, USA) on Day 0, with CIDR removal on Day 14, followed by 100 μg of gonadotropin-releasing hormone (GnRH; Factrel, Pfizer) on Day 16, and 25 mg of PGF2 (Lutalyse, Pfizer) on Day 23. Treatment 2 (n = 132) cows received the same synchronization treatment, except for an additional 25 mg dose of PGF2 given on Day 7 of CIDR treatment. Cows were observed for oestrus over an 84-h period and inseminated with X-sorted semen at 9 to 14, 15 to 17, 18 to 21 or 22 to 24 h after detected oestrus, followed 10 days later by exposure to fertile bulls for 45 days. Ultrasonography was used to determine pregnancy status ~45 days after AI and again 45 to 55 days after bull removal. Chi-squared analysis was used to determine the effects of treatment on oestrus response, AI pregnancy, and seasonal pregnancy rates, and the effect of AI timing on pregnancy rate. Analysis of variance was used to determine the effects of treatment on the interval from PGF2 dosing to detected oestrus. Oestrus response to synchronization treatment was similar (P = 0.33) at 76.5 and 71.2% for cows in Treatments 1 and 2, respectively. The mean interval from PGF2 to the onset of oestrus was extended (P = 0.03) ~3 h for cows in Treatment 2 (57.4 v. 54.3 h, respectively). About two-thirds of the cows in each treatment were cyclic at the start of synchronization. The extended interval from PGF2 to observed oestrus was due to an effect on cyclic, but not acyclic, cows in Treatment 2. Of the cows expressing oestrus, 69 and 89% expressed oestrus 48 to 72 h post-PGF2 in Treatments 1 and 2, respectively. Pregnancy rates after AI with sorted semen were similar (P = 0.64) at 63.3 and 66.7% for Treatments 1 and 2, respectively. No differences (P = 0.98) were detected in AI pregnancy rates for insemination intervals ranging from 9 to 24 h after detected oestrus. At the end of the breeding season, seasonal pregnancy rates were also similar (P = 0.74), at 83.3 and 84.9% for cows in Treatments 1 and 2, respectively. The addition of a PGF2 treatment on Day 7 of our 14-day CIDR-based protocol was expected to ensure all cows has sub-luteal P4 concentrations and would develop a persistent follicle capable of ovulation in response to GnRH given on Day 16. Whereas the Day 7 PGF2 treatment had no effect on oestrus response or pregnancy rate, it did result in a more synchronous oestrus within a 24-h period. Results indicate that acceptable pregnancy rates can be achieved in lactating beef cows when using sorted semen over a range of insemination times.

scholarly journals Ovulation rate, prolificacy and pregnancy rate in goats treated with oral glycerol

2016 ◽  
Vol 3 (1) ◽  
Author(s):  
Ubaldo Aguilar ◽  
Joel Hernández-Cerón ◽  
Yesmín Domínguez ◽  
Carlos Gutiérrez
Keyword(s):  
Oral Administration ◽  
Pregnancy Rate ◽  
Estrous Cycle ◽  
Ovulation Rate ◽  
Multiple Births ◽  
Control Group ◽  
Treatment Groups

This study tested whether the oral administration of glycerol at the time of progestin removal and in the first 6 days of the estrous cycle increased the ovulation rate, prolificacy, and pregnancy rate in goats. Intravaginal sponges impregnated with fluorogestone acetate were inserted into 129 goats for 12 days; upon sponge removal, goats were randomly assigned to one of the two following treatment groups: the glycerol group (n = 65), which received an oral drench of 100 mL of glycerol upon sponge removal and was repeated on days 0, 2, 4, and 6 following estrus (estrus = day 0), and the control group (n = 64), which did not receive glycerol. The goats in estrus were mated, and their ovulation rate was determined by ultrasonography between days 8 and 12 of the estrous cycle. Pregnancy was diagnosed by ultrasonography on day 40, and the prolificacy was determined at birth. In 6 goats treated with glycerol and 5 controls, their insulin concentrations at 0, 2, 4, 8, and 12 h after the glycerol drench were determined by radioimmunoassay. The proportion of goats with multiple ovulations (glycerol = 71 vs control = 64) and the proportion of goats with multiple births (glycerol = 52 vs control = 56) were similar (P > 0.05) between treatments. Likewise, the pregnancy rate was similar (P > 0.05) between treatments (glycerol = 88 vs control = 85%). The insulin concentrations tended to be higher in goats treated with glycerol (P = 0.08). In conclusion, an oral drench of 100 mL of glycerol at the time of progestin withdrawal and in the first 6 days of the estrous cycle did not increase the ovulation rate, prolificacy, or pregnancy rate in goats.

scholarly journals Effect of environmental enrichment for piglets in the nursery phase

2021 ◽  
Vol 34 (1) ◽  
pp. 154-160
Author(s):  
Joselaine Bortolanza Padilha-Boaretto ◽  
Priscila Michelin Groff-Urayama ◽  
Suelen Maria Einsfeld ◽  
Cleverson de Souza ◽  
Angélica Signor Mendes ◽  
...  
Keyword(s):  
Treatment Group ◽  
Environmental Enrichment ◽  
Experimental Period ◽  
Video Camera ◽  
Control Treatment ◽  
Control Group ◽  
Treatment Groups ◽  
Bonferroni Test ◽  
Parametric Analyses ◽  
Control Treatment Group

Objective: The effect of environmental enrichment on the behaviour of piglets in the nursery phase was evaluated.Methods: A total of 450 hybrid pigs (21 day old), including both females and uncastrated males, weighing approximately 6 kg, were distributed in a completely randomised design with 3 treatments and 3 replicates of 50 animals each. The treatments were: i) pen without environmental enrichment (control), ii) treatment consisting of continuous environmental enrichment (CEE) with rubber balls throughout the experimental period, and iii) treatment consisting of environmental enrichment with washed balls (EEWB) during the whole experimental period which were removed daily for washing. For the behavioural evaluation, 10 animals were randomly selected per replicate. The behavioural assessments were performed once a week, from 8 am to 6 pm, using images captured with a video camera. The data were submitted to non-parametric analyses, the means were compared using the Bonferroni test, and Person’s correlations were also calculated.Results: A statistical difference (p = 0.001) was observed in the B5 (playful) behaviour; the animals in the EEWB treatment group had a higher frequency of this behaviour than animals in the control treatment group. The animals in the control group showed a higher frequency of B7 behaviour (lying down) (p = 0.026) than those in the EEWB and CEE treatment groups. The animals in the control group had a higher frequency of the B9 (belly nosing) behaviour than those in the EEWB group (p = 0.015). There was a tendency towards a higher frequency of behaviour B3 (walking in the pen) (p = 0.067) when the animals received the control treatment than treatments EEWB or CEE.Conclusion: The use of an enriching object improved the animal welfare and altered the correlation between the evaluated behaviours compared to the animals that did not have environmental enrichment.

scholarly journals 9THE USE OF ECG TO INCREASE PREGNANCY RATES IN POSTPARTUM BEEF COWS FOLLOWING TREATMENT WITH PROGESTERONE VAGINAL DEVICES AND ESTRADIOL BENZOATE AND FIXED-TIME AI

2004 ◽  
Vol 16 (2) ◽  
pp. 127 ◽  
Author(s):  
G.A Bo ◽  
L. Cutaia ◽  
P. Chesta ◽  
D. Moreno
Keyword(s):  
Body Condition Score ◽  
Fixed Time ◽  
Beef Cows ◽  
Estradiol Benzoate ◽  
Pregnancy Rates ◽  
Control Group ◽  
Treatment Groups ◽  
Condition Score ◽  
N 93 ◽  
Rectal Palpation

Treatments with progesterone (P4) releasing devices and estradiol benzoate (EB) have been extensively used in fixed-time AI (FTAI) programs in beef cattle. However, pregnancy rates in postpartum cows kept on pasture often have been lower than expected because of poor body condition score (BCS) and a high incidence of anestrous. A recent study (Cutaia L et al., 2003 Theriogenology 59, 216) suggested that the addition of eCG to a P4/EB FTAI program may improve pregnancy rates in cows with fair to poor BCS, but results were not conclusive. Therefore, this experiment was designed to further investigate the effect of eCG treatment on pregnancy rates in postpartum beef cows in those conditions. The experiment was performed at 2 locations with lactating Angus cows (n=93), 60 to 90d postpartum with a BCS 1.9 (1 to 5 scale; Location 1), and crossbred Zebu cows (n=290), 60 to 90d postpartum with a BCS 2.0 (Location 2). In each Location, cows were randomly allocated to 1 of the following treatment groups: Control, eCG Day6, or eCG Day8. All cows received a P4 intravaginal device (DIB, Syntex, Argentina) and 2mg EB i.m. (Syntex) on Day0, 500mg cloprostenol (Estroplan, Syntex) at the time of DIB removal (Day8), 1mg EB i.m. on Day9 and FTAI 52 to 56h after DIB removal. Cows in the Control group received no further treatment, whereas cows in the eCG-treated groups received 400 IU eCG (Novormon 5000, Syntex) on Day6 or Day8. Cows were examined on Day0 by rectal palpation (Location 1) or by ultrasonography (US; Location 2) and were classified as those with a CL or without a CL, with either large (&gt;8mm) or small (&lt;8mm)small follicles. Pregnancy was determined by US 45d after FTAI. Data were analyzed by logistic regression and the effects of location, treatment, ovarian status, AI technician and semen were considered in the model. There was no effect of location (P=0.3), AI technician (P=0.2) or semen (P=0.8) on pregnancy rates. However, there was an effect of treatment (P=0.02), attributed to higher pregnancy rates in the eCG Groups than in the Control Group (Table). Furthermore, cows with a CL or without a CL but with large follicles on Day 0 had higher pregnancy rates than those with small follicles (P=0.04). It was concluded that the use of eCG in a P4/EB FTAI program improved pregnancy rates in postpartum beef cows that were in fair topoor BCS.

19 THE EFFECT OF FOLLICLE-STIMULATING HORMONE IN A MODIFIED CO-SYNCH SYNCHRONIZATION PROTOCOL ON SUBSEQUENT PREGNANCY RATES OF CROSSBRED LACTATING BEEF CATTLE

2013 ◽  
Vol 25 (1) ◽  
pp. 156
Author(s):  
L. R. Gentry ◽  
R. W. Walker ◽  
J. Lambe-Steinmiller ◽  
R. A. Godke ◽  
G. T. Gentry
Keyword(s):  
Treatment Group ◽  
Beef Cattle ◽  
Pregnancy Rate ◽  
Beef Cows ◽  
Subsequent Pregnancy ◽  
Pregnancy Rates ◽  
Reproductive Efficiency ◽  
Follicular Waves ◽  
Estrus Detection ◽  
Synchronization Protocol

Heritability of reproductive traits is relatively low, leaving only management strategies as an alternative to affect reproductive efficiency in beef cattle. The use of assisted reproductive technologies such as fixed-timed AI (FTAI) offers the ability to increase reproductive efficiency through selection of superior genetics and manipulation of calving dates through estrous-synchronization protocols. Application of these technologies has not been fully embraced by cattlemen due to variation in success rate, primarily associated with the apparent lack of control of follicular waves. While it has been reported that an endogenous increase in FSH precedes the emergence of follicular waves in cattle, we could find no reports on the effects of exogenous FSH on FTAI pregnancy rates. Artificial insemination remains the most important reproductive technology that could positively affect cattlemen. Therefore, this experiment was conducted to test the hypothesis that incorporation of FSH into the CO-Synch synchronization protocol would increase FTAI pregnancy rates in beef cattle. Crossbred beef cows (n = 182) with a mean body weight (BW) of 596 ± 6.6 kg and mean body condition score (BCS) of 5.4 ± 0.07 from 3 different locations were stratified across treatment groups by BW, BCS, and days postpartum or cyclicity status based on plasma progesterone concentrations. Females were estrus synchronized using the 7-day CO-Synch+CIDR protocol. All females received a CIDR insert and 100 µg of gonadotropin-releasing hormone (GnRH; Factrel) on Day 0, followed by CIDR removal, 25 mg of prostaglandin (Lutalyse) IM and fitted with an estrus-detection patch (Estrotect) on Day 7. On Day 2, all females (n = 92) in the FSH treatment group were administered 20 mg of FSH (Folltropin) IM and the remaining females (n = 90) served as nontreated controls. Fixed-timed AI was performed at 72 h following CIDR removal when all females were administered 100 µg of GnRH and the estrus-detection patch was evaluated. The overall FTAI pregnancy rate was 55% (100/182) and there was no difference (P = 0.41) in pregnancy rates across locations so the data were pooled and reanalyzed. Pregnancy rates were not affected (P = 0.54) by treatment group and were 52% (48/92) for the FSH-treated females and 58% (52/90) for the nontreated control group. Similarly, based on evaluation of the estrus-detection patch, there was no difference (P = 0.68) in the percentage of females responding to the synchronization protocol [61% (55/92) v. 68% (61/90)] and no difference (P = 0.55) in the pregnancy rate of responding females [62% (34/55) v. 69% (42/61)] for the FSH-treated and nontreated control groups, respectively. In conclusion, administration of FSH 10 days prior to FTAI in CO-Synch+CIDR synchronized crossbred beef cows did not increase subsequent pregnancy rates. However, exogenous FSH administration should be evaluated further to determine its effects, if any, on follicular dynamics related to FTAI in the lactating beef cow.

8 COMBINATION OF OESTRUS DETECTION AND FIXED-TIME ARTIFICIAL INSEMINATION IN BEEF HEIFERS FOLLOWING A SHORTENED OESTRADIOL-BASED PROTOCOL THAT PROVIDES FOR A LENGTHENED PROESTRUS

2015 ◽  
Vol 27 (1) ◽  
pp. 96 ◽  
Author(s):  
J. J. de la Mata ◽  
M. Ré ◽  
G. A. Bó
Keyword(s):  
Pregnancy Rate ◽  
Body Condition Score ◽  
Fixed Time ◽  
Beef Cows ◽  
Gonadotropin Releasing Hormone ◽  
Pregnancy Rates ◽  
Group V ◽  
Releasing Hormone ◽  
Treatment Groups ◽  
Condition Score

Studies have shown that gonadotropin-releasing hormone-based protocols that reduce the period of progestin insertion and prolong the period from progestin removal to gonadotropin-releasing hormone and fixed-time AI (FTAI; named 5-day Co-Synch) results in similar or higher pregnancy rates than the conventional 7-day Co-Synch protocol in beef cows and heifers (Bridges et al. 2008 Theriogenology 69, 843–851). Similar findings have been reported following the use of an oestradiol-based protocol that also provides for a longer period of proestrus (named J-Synch; de la Mata and Bó 2012 Taurus 55, 17–23). An experiment was designed to compare the J-Synch protocol for synchronization of ovulation that allows for a prolonged proestrus with a conventional 7-day oestradiol-based protocol for FTAI in heifers. Cycling 18-month old Angus and Hereford heifers (n = 208) with a body condition score of 6 to 7 (scale of 1 to 9) were randomly allocated to 1 of 2 treatment groups. Heifers in the 7-day EB group (n = 105) received a progesterone (P4) device (DIB 0.5 g of P4, Syntex SA, Buenos Aires, Argentina) and 2 mg of oestradiol benzoate (EB, Syntex SA) on Day 0 and 500 μg of cloprostenol (PGF; Ciclase DL, Syntex SA) and 0.5 mg oestradiol cypionate (Cipiosyn, Syntex SA) on the day of DIB removal (Day 7). Heifers were also tail painted at the time of DIB removal and observed for signs of oestrus (i.e. tail paint rubbed off). Those with the tail paint rubbed off by 36 h after DIB removal were inseminated 12 h later, whereas those not showing oestrus by 36 h were FTAI at 54 h. Heifers in the J-Synch group (n = 103) received DIB and 2 mg of EB on Day 0 and PGF on the day of DIB removal (Day 6). Heifers in this group were also tail painted at DIB removal, and those with their tail paint rubbed off by 48 h were inseminated 12 h later; those not showing oestrus by 60 h received 100 μg of gonadorelin acetate (gonadotropin-releasing hormone, Gonasyn gdr, Syntex SA) and were FTAI at 72 h after DIB removal. Pregnancy was diagnosed by ultrasonography at 55 days after FTAI (Honda 101V, 5.0-MHz transducer). Data were analysed by logistic regression. Oestrus detection rate and pregnancy rate to FTAI did not differ (P > 0.1) between groups (38.8%, 40/103 and 60.3%, 38/ 63 for heifers in the J-Synch group v. 28.5%, 30/105 and 45.3%, 34/75 for those in the 7-day EB group). However, pregnancy rates to observed oestrus tended (P < 0.09) to be higher and the overall pregnancy rate was significantly higher (P < 0.01) in heifers in the J-Synch group (80.0%, 32/40 and 67.9%, 70 /103) compared with those in 7-day EB group (50%, 15/30 and 46.6%, 49/105). Furthermore, heifers within the J-Synch group that had their tail paint rubbed off by 48 h after DIB removal and were AI 12 h later (i.e. 60 h) had higher (P < 0.05) pregnancy rate than those in the same group that were FTAI. In conclusion, reducing the time of progestin device insertion and lengthening the proestrus period, as in the J-Synch protocol, results in higher pregnancy rates than with the conventional oestradiol-based protocol. Furthermore, the combination of oestrus detection and FTAI would appear to improve the pregnancy outcome even more.

117 Effect of length of insertion of a progesterone device on follicular diameter, time of ovulation, and pregnancy rates in Bos indicus cows treated with an oestradiol/progesterone-based protocol with a prolonged proestrus

2021 ◽  
Vol 33 (2) ◽  
pp. 166
Author(s):  
A. V. Cedeño ◽  
G. A. Bó
Keyword(s):  
Body Condition Score ◽  
Day Treatment ◽  
Bos Indicus ◽  
Fixed Time ◽  
Beef Cows ◽  
Pregnancy Rates ◽  
Control Treatment ◽  
Control Group ◽  
Device Removal ◽  
And Control

Three experiments were designed to evaluate the effect of the length of insertion of a intravaginal progesterone (P4) device on follicular and corpus luteum (CL) diameter, time of ovulation, and pregnancy rates following fixed-time AI (P/FTAI) in Bos indicus cows treated with an oestradiol/P4-based treatment with a lengthened proestrus, named J-Synch. Multiparous suckled Bos indicus beef cows that were 35 to 60 days postpartum were used in Experiments 1 and 2, whereas non-lactating cows were used in Experiment 3. All cows had a CL or a follicle of at least 8mm in diameter and a body condition score between 2.5 and 4 (1 to 5 scale) at the time of treatment. On Day 0, all cows received 2mg of oestradiol benzoate (EB; Sincrodiol, Ourofino, Brazil) and a previously used intravaginal device (1g of P4; Sincrogest, Ourofino). The P4 device was removed on Day 6 in the J-Synch 6-day group and on Day 7 in the J-Synch 7-day and Control groups. All cows received 500µg of cloprostenol (Sincrocio, Ourofino) and 400IU of equine chorionic gonadotrophin (SincroeCG, Ourofino) at the time of P4 device removal, and cows in the Control group also received 0.5mg of oestradiol cypionate (ECP, SincroCP, Ourofino) at the same time. In Experiment 1, cows (n=20 per group) were examined every 12h, from P4 device removal to determine the time of ovulation and 7 days after ovulation to measure the CL. In Experiment 2, all cows (n=200 per group) were tail-painted for oestrous detection. Cows with=50% of the tail-paint rubbed-off by 72h (J-Synch groups) or 48h (Control group) after P4 device removal, were FTAI at that time. Cows not designated as showing oestrus at that time received 10µg Buserelin (GnRH, Sincroforte, Ourofino) and were FTAI 8h later. In Experiment 3, P/FTAI was compared in cows that received the J-Synch 7-day treatment (n=265) or the 7-day Control treatment (n=250). Data were analysed using the GLM mixed procedure (InfoStat). In Experiment 1, the diameter of the ovulatory follicle was larger (P&lt;0.05) and the interval to ovulation was longer (P&lt;0.05) in the J-Synch groups (J-Synch 7 d: 16.4±0.2mm and 86.0±3.0 h; J-Synch 6 d:15.5±0.3mm and 83.0±4.0h) than in the Control group (13.8±0.2mm and 64.0±3.0h). Furthermore, CL diameter was greater (P&lt;0.05) in the J-Synch 7-day group (21.9±0.8mm) than in the J-Synch 6-day (18.7±0.8mm) and Control (16.8±0.9mm) groups. In Experiment 2, P/FTAI was higher (P&lt;0.05) in the J-Synch 7-day group (116/200; 58.0%) than in the J-Synch 6-day (93/200; 46.5%) and Control (98/200; 49.0%) groups. In Experiment 3, P/FTAI was higher (P&lt;0.05) in the J-Synch 7-day group (161/265; 60.7%) than in the Control group (124/250; 49.6%). In conclusion, delaying the removal of the P4 device by 1 day (i.e. Day 7 vs. Day 6) in the J-Synch protocol and lengthening the proestrous period (i.e. J-Synch 7-day vs. 7-day Control) resulted in higher P/FTAI in Bos indicus cows.

Hormonal stimulation and some risk factors studied to improve bovine pregnancy rate at the Coastal areas of Barisal district of Bangladesh

2018 ◽  
Vol 52 (1-4) ◽  
pp. 22-30
Author(s):  
A K Paul ◽  
S M T Rahman
Keyword(s):  
Pregnancy Rate ◽  
Coastal Region ◽  
Hormonal Treatment ◽  
Coastal Areas ◽  
Pregnancy Rates ◽  
Hormonal Stimulation ◽  
Crossbred Cows ◽  
Treatment Groups ◽  
History Of ◽  
Group A

Hormonal treatment of cows at the coastal region of Barisal district of Bangladesh was performed to assess the improvement of pregnancy rate. A total of 100 cows and heifers with irregular history of cyclicity were selected randomly and divided into five treatment groups. The groups were A (treated with anthelmintic), B (treated with anthelmintic, vitamin ADE and multivitamin powder), C (treated with PGF2α), D (treated with GnRH) and E (treated with GnRH and PGF2α). Each group comprised of 20 animals. The age, breed and parity of experimental cows were considered during treatment. In the study, the cows treated with both GnRH and PGF2α (group E) showed significantly (p<0.05) higher estrus (80%) and pregnancy rate (60%) than that of group A, B, C and D. The overall estrus rates of local and crossbred cows were 64% and 70%, respectively and the pregnancy rates were 40 and 52%, respectively. The crossbred cows responded significantly (p<0.05) to hormonal treatment than that of local cows. Parity-2 cows showed higher estrus sign than that of other parities. However, the pregnancy rates were higher significantly (p<0.05) in parity-2 and parity ≥4 cows than that of parity-0, parity-1 and parity-3 cows. The pregnancy rate was also found higher in case of 4 to <5 years old cows than that of 2 to <3, 3 to <4, 5 to <6, and ≥6 years old. It may conclude that the hormonal regimen increases the pregnancy rate as well as decreases the undesired waiting of estrus and conception. Further study with more sample size will reveal the more effective treatment for cows at the coastal areas of Bangladesh.

Hormonal stimulation and some risk factors studied to improve bovine pregnancy rate at the Coastal areas of Barisal district of Bangladesh

2018 ◽  
Vol 52 (1-4) ◽  
pp. 22-30
Author(s):  
A K Paul ◽  
S M T Rahman
Keyword(s):  
Pregnancy Rate ◽  
Coastal Region ◽  
Hormonal Treatment ◽  
Coastal Areas ◽  
Pregnancy Rates ◽  
Hormonal Stimulation ◽  
Crossbred Cows ◽  
Treatment Groups ◽  
History Of ◽  
Group A

Hormonal treatment of cows at the coastal region of Barisal district of Bangladesh was performed to assess the improvement of pregnancy rate. A total of 100 cows and heifers with irregular history of cyclicity were selected randomly and divided into five treatment groups. The groups were A (treated with anthelmintic), B (treated with anthelmintic, vitamin ADE and multivitamin powder), C (treated with PGF2α), D (treated with GnRH) and E (treated with GnRH and PGF2α). Each group comprised of 20 animals. The age, breed and parity of experimental cows were considered during treatment. In the study, the cows treated with both GnRH and PGF2α (group E) showed significantly (p<0.05) higher estrus (80%) and pregnancy rate (60%) than that of group A, B, C and D. The overall estrus rates of local and crossbred cows were 64% and 70%, respectively and the pregnancy rates were 40 and 52%, respectively. The crossbred cows responded significantly (p<0.05) to hormonal treatment than that of local cows. Parity-2 cows showed higher estrus sign than that of other parities. However, the pregnancy rates were higher significantly (p<0.05) in parity-2 and parity ≥4 cows than that of parity-0, parity-1 and parity-3 cows. The pregnancy rate was also found higher in case of 4 to <5 years old cows than that of 2 to <3, 3 to <4, 5 to <6, and ≥6 years old. It may conclude that the hormonal regimen increases the pregnancy rate as well as decreases the undesired waiting of estrus and conception. Further study with more sample size will reveal the more effective treatment for cows at the coastal areas of Bangladesh.

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