scholarly journals 202 Repeatability of estrus detection patch readings and relationship with breeding success

2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 30-31
Author(s):  
Vitor R G Mercadante ◽  
Robin R White ◽  
Heather L Bradford ◽  
Nicholas W Dias ◽  
Claire Timlin ◽  
...  

Abstract The objective of this study was to assess how well estrus detection patch readings correlated to successful AI breedings and to characterize the within-cow repeatability of estrus detection patch readings across breeding seasons. Data from the Virginia Department of Corrections beef cattle herds were collated for 7 locations over 7 years, with 2 calving seasons per year. Data from Spring of 2011 were missing. The full dataset contained 19,253 individual animal observations, of which 2,389 observations were omitted for failure to report estrus detection patch data. The relationship between estrus patch reading and pregnancy rate to fixed-time AI and subsequent natural service pregnancy rate was assessed by calculating the sensitivity and specificity of patch readings within each location during each breeding season. A true positive was defined as a patch activating and a cow being confirmed pregnant. A true negative was a patch remaining in the non activated state and a cow being confirmed open. A false positive was defined as a patch activating and a cow being confirmed open. A false negative was a patch failing to activate and a cow being confirmed pregnant. Pregnancy rate to AI sensitivity ranged from 0.2 to 1 with a mean of 0.583. Specificity ranged from 0 to 1 with a mean of 0.525. Subsequent natural service pregnancy rate), ranges in sensitivity (0.197 to 1.00, mean 0.563) and specificity (0 to 1, mean 0.545) were similar. Of the 6,249 animals with usable patch data, 934 never presented with an activated patch and 2,064 presented with an activated patch every breeding season. The remaining 3,251 animals averaged presenting with an activated patch 47% of the time and a non-activated patch 46% of the time. Odds of getting pregnant by AI for cows that always flag with the heat patch were 0.415.

2020 ◽  
Vol 98 (Supplement_2) ◽  
pp. 45-45
Author(s):  
Stefania Pancini ◽  
Jhon F Currin ◽  
Jamie L Stewart ◽  
Sherrie Clark ◽  
Tracey Redifer ◽  
...  

Abstract The objective of this study was to evaluate the effect of an injectable multi-mineral complex supplementation on beef cows overall mineral status and fertility. This study involved 9 different locations in the state of Virginia and a total of 1,128 Angus crossbred multiparous cows. All cows had ad libitum access to forage and water, and received mineral supplementation in form of mineral blocks. All cows were enrolled in a 7-d CO-Synch + CIDR fixed-time AI (FTAI) protocol, followed by natural service for an approximately 70-d breeding season. At the initiation of the FTAI protocol (d 0) cows were stratified by days post-partum (82 ± 18 d) and randomly assigned to one of two treatments: 1) One dose of an injectable trace mineral containing zinc (60mg/ml), copper (15mg/ml), selenium (5mg/ml) and manganese (10mg/ml) on d 0 (n = 560; 1 ml/90 kg BW of Multimin® 90, Multimin USA, Ft. Collins, CO); or 2) a negative control with no trace mineral injection (n = 568). BCS was recorded at d 0, 61 and 121. Estrus detection was recorded at d 10 using an estrus detection patch. Pregnancy was diagnosed on days 71 and 131 by ultrasonography. Liver biopsies were collected on days 0 and 45 in a subgroup of 140 cows from both treatments and distributed among all locations. No differences between treatments were detected in days post-partum (P = 0.83), BCS (P ≥ 0.42) and estrus detection (P= 0.12), neither in mineral status of copper, manganese, selenium or zinc (P ≥ 0.28). No effect of treatment was detected (P ≥ 0.20) in AI pregnancy rate (57%) or overall pregnancy rate (93%). In conclusion, one dose of injectable trace mineral administrated 10 days before AI did not improve pregnancy rate or overall mineral status in multiparous beef cows enrolled in FTAI.


2019 ◽  
Vol 97 (Supplement_1) ◽  
pp. 20-20
Author(s):  
Claire L Timlin ◽  
Laura Hungerford ◽  
Tracey Redifer ◽  
John F Currin ◽  
Vitor R G Mercadante

Abstract This retrospective study analyzed the effect of bull:cow ratio on pregnancy rates of cows returning to estrus after enrollment in fixed-time artificial insemination (TAI). Data were compiled over the course of 6 breeding seasons between 2014 and 2017 from the Virginia Department of Corrections herd containing 15 farms and 141 groups of cows (average 44 cows/group). Multiparous cows aged 2 years and older (n = 6002) were exposed to estrus synchronization. Non-pregnant cows after TAI (n=3079, average 21 cows/group) were exposed to natural service with bulls diagnosed as fertile by a breeding soundness exam. Percent data were given an arcsine transformation. A one-way ANOVA evaluated TAI rates by season and a linear regression was performed to compare conception rates to the bull:cow ratio. Pregnancy rate to TAI among groups averaged 53% and ranged from 11% to 83%. First bull pregnancy rate of cows returning to estrus was 47% overall, with fall seasons having greater conception rates than spring (51.1% vs. 44.5%, P = 0.03). The ratio of bulls to total number of cows ranged from 1:8 to 1:68 with an average ratio of 1:28. The ratio of bulls to the number of open cows ranged from 1:2 to 1:39 with an average ratio of 1:14. There was no correlation between the bull:cow ratio and return to estrus pregnancy rate (r = -0.12), and there was no correlation between the number of open cows per bull and return to estrus conception rates (r = -0.17). Thus, higher bull:cow ratios (between 1:8 and 1:68) did not effect return to estrus pregnancy rate; producers may consider a lower number of bulls needed for natural service breeding post TAI, decreasing bull related costs and increasing the economic feasibility of adopting TAI protocols.


Author(s):  
Claire L Timlin ◽  
Nicholas W Dias ◽  
Laura Hungerford ◽  
Tracey Redifer ◽  
John F Currin ◽  
...  

Abstract This retrospective study aimed to determine if the number of cows exposed per bull affects pregnancy rates of cows returning to estrus after fixed-time artificial insemination (FTAI). Data were compiled over the course of 13 breeding seasons (6 fall and 7 spring seasons) between 2010 and 2017 from the Virginia Department of Corrections herd. Available records contained data from 17 farms and 324 groups of cows (average 47 cows/group). Multiparous cows and heifers (average age per group: 5.11 ± 0.14 years; n = 14,868) were exposed to FTAI. After FTAI, animals were placed on pasture with bulls diagnosed as fertile by a breeding soundness exam for natural service of cows who did not become pregnant to FTAI (n = 7,248; average 22 cows/group). Animals were classified as pregnant to FTAI, to natural service on first return to estrus, or to natural service on second or subsequent estrus determined by fetal aging at pregnancy diagnosis. The bull:cow ratio for the total number of cows exposed ranged from 1:9 to 1:73 with an average of 1:31. The bull:cow ratio considering only open cows exposed after FTAI ranged from 1:2 to 1:44 with an average of 1:14. There was significant negative, small correlation between the bull:cow ratio for total number of cows exposed and return to estrus pregnancy rate in fall breeding seasons (P = 0.01, r 2 = 0.04) but not in spring (P = 0.90). There was a significant negative, small correlation between bull:cow ratio of open cows exposed and pregnancy rates to first return to estrus in fall herds with a single sire (P < 0.001, r 2 = 0.11). There was no correlation in fall herds using multiple sires or spring herds (P ≥ 0.12). Bull:cow ratio accounted for only 1 – 11% of variation in the pregnancy rates, thus we conclude that a decreased bull:cow ratio (up to 1:73) did not affect natural service return to estrus pregnancy rate. Cattlemen may consider a reduced number of bulls needed for natural service breeding after FTAI, which can decrease bull related costs and increase the economic feasibility of adopting FTAI protocols.


2019 ◽  
Vol 97 (Supplement_1) ◽  
pp. 1-1
Author(s):  
Claire L Timlin ◽  
Laura Hungerford ◽  
Tracey Redifer ◽  
John F Currin ◽  
Vitor R G Mercadante

Abstract This retrospective study analyzed the effect of bull:cow ratio on pregnancy rates of cows returning to estrus after enrollment in fixed-time artificial insemination (TAI). Data were compiled over the course of 6 breeding seasons between 2014 and 2017 from the Virginia Department of Corrections herd containing 15 farms and 141 groups of cows (average 44 cows/group). Multiparous cows aged 2 years and older (n = 6002) were exposed to estrus synchronization. Non-pregnant cows after TAI (n = 3079, average 21 cows/group) were exposed to natural service with bulls diagnosed as fertile by a breeding soundness exam. Percent data were given an arcsine transformation. A one-way ANOVA evaluated TAI rates by season and a linear regression was performed to compare conception rates to the bull:cow ratio. Pregnancy rate to TAI among groups averaged 53% and ranged from 11% to 83%. First bull pregnancy rate of cows returning to estrus was 47% overall, with fall seasons having greater conception rates than spring (51.1% vs. 44.5%, P = 0.03). The ratio of bulls to total number of cows ranged from 1:8 to 1:68 with an average ratio of 1:28. The ratio of bulls to the number of open cows ranged from 1:2 to 1:39 with an average ratio of 1:14. There was no correlation between the bull:cow ratio and return to estrus pregnancy rate (r = -0.12), and there was no correlation between the number of open cows per bull and return to estrus conception rates (r = -0.17). Thus, higher bull:cow ratios (between 1:8 and 1:68) did not effect return to estrus pregnancy rate; producers may consider a lower number of bulls needed for natural service breeding post TAI, decreasing bull related costs and increasing the economic feasibility of adopting TAI protocols


2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 116-117
Author(s):  
Emily G Smith ◽  
Rachael C Bonacker ◽  
Carson M Andersen ◽  
Jordan M Thomas

Abstract Estrus detection patches were evaluated as a tool to classify postpartum cows as estrous cycling or anestrous at the start of the breeding season. EstrotectTM Breeding Indicators were applied to 257 postpartum beef cows in three locations 25 days prior to the start of estrus synchronization. Coincident with the start of estrus synchronization, patches were scored using a 1 to 4 scale (1 = 0–25%; 2 = 25–50%; 3 = 50–75%; 4 = 75–100%) with scores of 3 or 4 considered activated. Blood samples were collected from each cow 10 days prior to, and at the start of the estrus synchronization. Serum progesterone concentrations were determined via radioimmunoassay; cows were considered estrous cycling if one or both samples exceeded a concentration of 0.5 ng/ml. Based on progesterone, 54.9% of cows were estrous cycling at the start of estrus synchronization. When missing patches were considered inconclusive results, use of patches to infer estrous cyclicity resulted in 85.0% sensitivity and 79.2% specificity with a positive predictive value of 87.2%. However, 75.1% of all cows presented with missing patches at the start of synchronization. If missing patches were considered activated, sensitivity was 95.7%, but specificity (16.4%) and PPV (58.2%) were poor, as 47.6% of cows presenting with missing patches were anestrous based on progesterone. Across all cows, pregnancy rate to AI was 58.0% (149/257). Cows with activated patches that were classified as false positives based on serum progesterone concentrations achieved a 71.4% (5/7) pregnancy rate to AI, raising questions as to whether sensitivity was underestimated due to inherent Type II errors in classification of cyclicity via progesterone. In summary, estrus detection aids are a sensitive tool to identify estrous cycling postpartum cows prior to the start of the breeding season; however, poor specificity and patch retention are limitations for this application.


2019 ◽  
Vol 59 (2) ◽  
pp. 225 ◽  
Author(s):  
Walvonvitis Baes Rodrigues ◽  
Jean do Prado Jara ◽  
Juliana Correa Borges ◽  
Luiz Orcirio Fialho de Oliveira ◽  
Urbano Pinto Gomes de Abreu ◽  
...  

The objective of this trial was to evaluate different post-timed artificial insemination (TAI) reproductive managements in postpartum beef cows to produce crossbred calves from artificial insemination (AI). Nellore cows (n = 607), with 45 days postpartum, were inseminated at a fixed time, using a protocol that included an intravaginal progesterone-releasing device along with oestradiol benzoate, prostaglandin, equine chorionic gonadotropin, and oestradiol cypionate, followed TAI 48 h post-device removal. Four post-TAI treatments were evaluated: in CONTROL (T1, n = 161), cows were exposed to Nellore clean-up bulls until the end of the breeding season (75 days). In OBSERVATION (T2, n = 132), heat detection was performed for 15–25 days post-TAI, followed by AI. In RESYNC22 (T3, n = 157) and RESYNC30 (T4, n = 157), resynchronisation started after 22 or 30 days, following second TAI at Day 32 or 40 days after first TAI. In T2, T3 and T4, after the second AI, cows were exposed to Nellore clean-up bulls until the end of the breeding season (75 days). The pregnancy rate (PR) for the first TAI did not differ (54.6%, 53.0%, 59.2%, and 51.6% for CONTROL, OBSERVATION, RESYNC 22, and RESYNC 30, respectively; P = 0.66), and no difference was observed for the second TAI (RESYNC 22 = 45.31% and RESYNC30 = 46.05%; P = 0.137), in the PR at the end of the breeding season (86.33%, 86.36%, 78.98%, and 81.52%, P = 0.43), or embryonic losses (4.54%, 2.85%, 6.45% and 7.40%, respectively; P = 0.61), but the percentage of crossbred pregnancy was higher in groups with resynchronisation (RESYNC22 and RESYNC30) than CONTROL and OBSERVATION (98.38%, 90.62%, 63.30%, 78.95%, P < 0.001). In conclusion, resynchronisation programs of 22 or 30 days are more efficient to produce AI products, and the final pregnancy rate is similar among the treatments, differing only in the amount of calves produced by AI.


2021 ◽  
Vol 26 (2) ◽  
pp. e2130
Author(s):  
José Francisco Martínez-Albarrán ◽  
Carlos Salvador Galina-Hidalgo ◽  
Ivette Rubio-Gutiérrez ◽  
Wendy Leticia Balam-Villarreal ◽  
Manuel D. Corro-Morales

Objective. To compare the reproductive performance of postpartum and open Bos indicus cows and to study the cost effectiveness of retaining non-pregnant animals after a short breeding season in tropical region of Mexico. Material and Methods. A total of 128 Bos indicus were included, 87 postpartum cows (PP) with ≤90 days after calving and 41 open cows (OC) with >90 days open. The study was divided into three phases: 1) Estrus synchronization followed by FTAI (day 0-10), 2) Estrus detection and AI (day 11-45) and 3) Natural mating (day 46-90). For the first phase, all animals were synchronized and AI at fixed time (day 10). Cows displaying overt signs of estrus (day 11-45) were AI. Open cows during the previous two phases were exposed to the bull. Results. Pregnancy in phase 1 was different (p<0.01) for PP and OC groups, 58.6% and 34.1%, respectively. Overall pregnancy percentage over the second service was 42.5% (p>0.05). No differences (p>0.05) were observed at phase 3, average 44.2%. By the end of the breeding season, the cost of OC, was 3 times more than PP cows. Conclusions. Pregnancy rate at first phase was higher in PP cows than OC cows. At the end of breeding season, a pregnancy rate of 80% was found. Incorporation of open cows from previous breeding season was more expensive than PP cows in all phases of the breeding program. Retaining an open cow for rebreeding one year or more could not be economically feasible.


2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 117-117
Author(s):  
Stefania Pancini ◽  
John Currin ◽  
Jamie L Stewart ◽  
Sherrie Clark ◽  
Tracey Redifer ◽  
...  

Abstract The objective of this study was to evaluate the effect of two doses of an injectable multi-mineral complex supplementation on beef cow fertility and overall mineral status. A total of 986 Angus crossbred multiparous cows at 8 locations in Virginia were enrolled in a 7-day CO-Synch+CIDR fixed-time artificial insemination (FTAI) protocol, followed by natural service for an approximately 70 d breeding season. All cows had ad libitum access to water, mineral blocks, and diet composed of hay, grass, sudangrass, sorghum grain and commodity pellets, depending on location. Approximately 30 days before calving (d -120, day of AI is d 0) cows were randomly assigned to one of two treatments: 1) Two doses (6 mL) of Multimin® 90 (Multimin USA, Ft. Collins, CO) at d -120 and d -10 (MIN; n = 494); or 2) a negative control with no trace mineral injection (CTRL; n = 492). Body condition score was recorded on d -10, 60 and 120. Estrus detection was recorded at d 0 using estrus detection patches. Pregnancy was diagnosed on d 60 and 120 by ultrasonography. Liver biopsies were collected on d -10 and 60 in a subgroup of 60 cows equally distributed between treatments and among all locations. No differences between treatments were detected in days post-partum (P = 0.66), BCS (P = 0.24) and estrus expression (P = 0.11). Mineral status of copper, manganese, selenium or zinc was similar between treatments before (P = 0.20) and after treatment (P = 0.17). No effect of treatment was detected in FTAI pregnancy rate (50.8%, P = 0.52) or overall pregnancy rate (89.6%, P = 0.64). Two doses of injectable trace mineral administrated approximately 30 days before calving and 10 days before FTAI did not improve pregnancy rate or overall mineral status in multiparous beef cows in Virginia.


2005 ◽  
Vol 17 (2) ◽  
pp. 231
Author(s):  
J. Lagioia ◽  
M. Panarace ◽  
M. Marfil ◽  
M. Basualdo ◽  
J. Gutierrez ◽  
...  

The most important factor in bovine embryo transfer programs is the low efficiency in the utilization of the recipients; this low efficiency is associated with low response to synchronization protocols and failures in estrus detection. It has been shown that cows transferred at fixed time with in vivo-derived embryos resulted in high rates of recipients selected for transfer and high overall pregnancy rates (recipients pregnant/recipients treated) (Tribulo et al. 2002 Theriogenology 57, 563). An experiment was designed to evaluate the pregnancy rate in recipients transferred with in vivo (fresh and frozen), IVF, and cloned-derived embryos without estrus detection. A total of 1555 non-lactating Bos Taurus crossbred beef cows was divided into two groups. Cows from group 1 (n = 421) were synchronized with a progesterone intravaginal releasing device (1 g P4; DIB, Syntex®, Buenos Aires, Argentina) plus 2 mg of estradiol benzoate (EB) i.m. (Syntex®) on Day 0. On Day 5, they received 400 IU of eCG (Novormon 5000, Syntex®) i.m. and 150 μg of D-Cloprostenol (PGF2α) (Bioprost-D, Biotay®, Buenos Aires, Argentina). The DIB devices were removed on Day 8 and on Day 9, 1 mg of EB was injected. Day 10 was arbitrarily considered as the day of estrus. Cows from group 2 (n = 1134) received 2 doses of PGF2α 14 days apart and were checked for heat during 5 days after the second PGF2α dose. Cows of both groups were examined 7 days after estrus by ultrasonography (Pie Medical Scanner 200®) and those with a corpus luteum >10 mm of diameter were transferred nonsurgically with in vivo (fresh and frozen), IVF, and cloned-derived embryos. In group 1, 360 cows were transferred, and in group 2, 726 cows were transferred (Table 1). Pregnancy was diagnosed 23 days later by ultrasonography (Pie Medical Scanner 200®). The pregnancy rates were compared statistically between groups 1 and 2 by analysis of variance (Infostat, LSD Fisher). There was no significant statistic difference (P > 0.05) between pregnancy rate in group 1 and 2 with in vivo (fresh), IVF, and cloned-derived embryos. However, pregnancy rate of frozen in vivo-derived embryos was lower in group 1 than in group 2 (P < 0.05). Results showed that treatment using DIB combined with EB, PGF2α, and eCG associated with embryo transfer without estrus detection (group 1) had no difference in pregnancy rate when compared with the treatment where synchronization with PGF2α and heat detection were used (group 2). Another important advantage is the use the group 1 treatment for increasing the flexibility and efficiency in the management of the recipients of in vivo, IVF, and cloned-derived embryo transfer programs. Table 1. Comparison of pregnancy rates between group 1 (embryo transfer at fixed time) and group 2 (embryo transfer 7 days after estrus detection)


2011 ◽  
Vol 35 (2) ◽  
pp. 95-104
Author(s):  
HA . AL-Mutar

Present experimental was carried out on 22 does 2-4 years old. The aim was to induction of estrous in non-breeding season using impregnated sponge with 20 mg of medroxy progesterone acetate (MPA) for 13 days and with an i/m injection of 500 IU Pregnant Mare Serum Gonadotropin (PMSG) hormone 24 hrs before sponge withdrawal and to compare the pregnancy rate using three different methods of insemination; natural , cervical and laparoscopic artificial insemination at fixed time 24-48 hrs after estrous onset. All does were showed signs of estrous (100%), the estrous time was 46.9±4.90hrs (24-60hrs) after sponge withdrawal. While estrous length was 37.09±1.91 (24–72hrs). All experimental animals followed up by abdominal palpation, ultrasonography at 30, 60 and 90 days post-insemination, while the laparoscopic examination was performed at day 30 post-insemination, to improve the efficiently of the different methods of inseminations in pregnancy rate ultrasonographical diagnosed by rectal and abdominal methods of 14 does post-inseminations appeared that two were pregnant, seven suspected and five non pregnant. At day 60th , post-insemination the pregnancy diagnosis of (22) does appeared that (14) were pregnant, six suspected and two non pregnant. While at day 90, the examination of all does appeared that (16) animals were pregnant and six were not. The laparoscopic examination, at 30 days post-insemination showed that eight does were pregnant, two suspected and two were not pregnant. In conclusion that the pregnancy rate of laparoscopic insemination is (75%), comparisons to natural (66.7%) and cervical AI method (75%) but there is no significant different between them, while the kidding percentage was appear in natural insemination (75%), cervical (100%) and laparoscopic insemination (150%). The results of this study indicate that estrus can be efficiently induced in female goats during non-breeding season using 20mg MPA impregnated spongewith 500IU PMSG.


Sign in / Sign up

Export Citation Format

Share Document