Clitoral stimulation and the effect of age, breed, technician, and postpartum interval on pregnancy rate to artificial insemination in beef cattle

Abstract The objective of this experiment was to evaluate the effect of clitoral stimulation post-insemination on pregnancy rates in Bos indicus beef cattle. A total of 1186 multiparous Nelore cows were assigned to an estradiol-based estrus synchronization + timed-AI protocol (FTAI, d 0), and randomly assigned to receive either 2 to 5 seconds of clitoral stimulation or no clitoral stimulation after artificial insemination. Estrus expression prior to AI was evaluated based on patch activation (estrus, ≥ 50% activated; no estrus, < 50% activated) using Estrotect Heat Detector and chute exit velocity after AI was evaluated. Individual exit score was calculated within each group by dividing exit velocity into quintiles and assigning cows with a score from 1 to 5 (1 = slowest; 5 = fastest). Artificial insemination was performed by 7 different technicians. Pregnancy diagnosis was performed 30 days after FTAI via transrectal ultrasonography. Overall pregnancy rate at day 30 was 46.0% (545/1186). Clitoral stimulation had no beneficial effect (P = 0.42) on pregnancy rate of multiparous cows when compared to those not stimulated (47.5% ± 4.6 vs. 44.3% ± 4.6). Cows that expressed heat at d 0 (n = 602) had a greater (P < 0.01) pregnancy rate compared to no heat expression (37.6% ± 4.7 vs. 60.6% ± 4.6), but no effect of the clitoral stimulation was observed on pregnancy rate in cows that did or did not express heat (P > 0.05). Furthermore, clitoral stimulation did not affect exit score (P = 0.67) of cows after FTAI. No effect of the technician was observed on pregnancy rate when clitoral stimulation was applied or not (P = 0.21). In summary, clitoral stimulation was not a useful managerial tool to improve pregnancy rate in multiparous Bos indicus cows submitted to FTAI using estradiol-based protocols.

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AVALIAÇÃO DO DESEMPENHO REPRODUTIVO DE VACAS NA REGIÃO DO PANTANAL SUL-MATO-GROSSENSE SUBMETIDAS A IATF Com Aplicação De GnRH

Nativa ◽

10.31413/nativa.v9i3.11184 ◽

2021 ◽

Vol 9 (3) ◽

pp. 281-285

Author(s):

Gabriel Rodrigo Hass Perucchi ◽

Gabriela de Souza Sartori ◽

Richarlla Aparecida Buscariol Silva ◽

Murilo da Silva Garcia ◽

Rodrigo José Delgado Jardim ◽

...

Keyword(s):

Beef Cattle ◽

Pregnancy Rate ◽

Reproductive Performance ◽

Artificial Insemination ◽

Body Condition Score ◽

The Body ◽

Mato Grosso ◽

Condition Score ◽

Timed Artificial Insemination ◽

Mato Grosso Do Sul

A Inseminação artificial em tempo fixo (IATF) está se difundindo no Brasil, pois contribui para o aumento da produtividade. O objetivo neste trabalho foi avaliar o uso do GnRH em protocolos de IATF de vacas criadas no pantanal Sul-mato-grossense. Participaram da pesquisa 531 vacas paridas da raça Nelore, que foram avaliadas de acordo com o escore de condição corporal (ECC), submetidas a três tipos de protocolos de IATF (lote 1, 2 e 3). Após 40 dias da inseminação artificial foi realizado diagnóstico de gestação. As matrizes que não receberam GnRH no lote 1 (estro aparente), lote 2 (estro parcial) e lote 3 (sem apresentação de estro) apresentaram, respectivamente 55,4%, 19,2% e 25,9% de prenhez, enquanto as que receberam o fármaco apresentaram 48,6%, 37,2% e 38,8%. Relacionado ao ECC, pode-se observar que a maior taxa de prenhez ocorreu em animais com ECC 3. Primíparas apresentaram melhor taxa de prenhez quando receberam GnRH independente do ECC. Concluiu-se que o uso de GnRH mostrou-se eficiente para melhoria da taxa de prenhez principalmente em primíparas, assim como nos animais que não apresentaram estro ou apresentaram estro parcial, e que matrizes com ECC 3 apresentaram melhores taxas de prenhez que vacas com escore inferior. Palavras-chave: bovino de corte; inseminação artificial em tempo fixo; produtividade; GnRH; Nelore. Evaluation of cow reproductive performance in the region of Mato Grosso do Sul swamp submitted to TAI with GnRH application ABSTRACT: The technique of timed artificial insemination (TAI) is spreading in Brazil, as it contributes to the increase of productivity. The objective of this work was to evaluate the use of GnRH in TAI protocols of cows raised in the swamp of Mato Grosso do Sul. 531 Nelore breed calved cows participate in the survey, which were evaluated according to the body condition score (BCS), and then performed three types of TAI protocols (batch 1, 2 and 3). After 40 days of the insemination, a pregnancy diagnosis was made. The matrices that did not receive GnRH in batch 1 (apparent oestrus), batch 2 (partial oestrus) and batch 3 (no oestrus presentation) presented respectively 55.4%, 19.2% and 25.9% of pregnancy, while those receiving the drug showed 48.6%, 37.2% and 38.8%. Related to BCS, it can be observed that the highest pregnancy rate occurred in animals with BCS 3. Primiparous had a better pregnancy rate when receiving GnRH regardless of BCS. It was concluded that the use of GnRH was efficient to improve the pregnancy rate mainly in primiparous as well as animals that showed no oestrus or partial oestrus, and matrices with BCS 3 had better pregnancy rates than cows with lower scores. Keywords: beef cattle; timed artificial insemination; productivity; GnRH; Nelore.

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Impact of the quality of life of inseminators on the results of artificial insemination programs in beef cattle

Revista Brasileira de Zootecnia ◽

10.1590/s1516-35982010000700009 ◽

2010 ◽

Vol 39 (7) ◽

pp. 1457-1463

Author(s):

Lívia dos Santos Russi ◽

Eliane Vianna da Costa-e-Silva ◽

Carmem Estefânia Serra Neto Zúccari ◽

Caciliana da Silva Recalde ◽

Norly Gomes Cardoso

Keyword(s):

Beef Cattle ◽

Pregnancy Rate ◽

Artificial Insemination ◽

Life Quality ◽

Work Conditions ◽

Pregnancy Rates ◽

Open Questions ◽

Timed Artificial Insemination ◽

And Training

The objective of the present study was to evaluate the effect of factors of personal life and work conditions on the results obtained by inseminators in conventional and fixed-timed artificial insemination programs in beef cattle. Inseminators from three farms (21 in the total) were interviewed and evaluated according to the general obtained pregnancy rates. The differences among the pregnancy rates obtained in the farms, motivation and its association with the obtained pregnancy rate and the effect of each variable of the groups of needs on the pregnancy rate at first insemination were evaluated. The open questions were grouped by similarity and then analyzed by frequency of the answers. Pregnancy rates obtained by the inseminators ranged from 12 to 57%, with a mean service index of 3.10 ± 1.62 doses/pregnancy. It was also observed that the satisfaction of biological, financial, and training needs was more intimately related to the pregnancy rate than the satisfaction of the other needs, although none had shown an antagonistic relationship with it. Factors concerned to life quality and to the work can be important in determining the performance of these professionals.

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375 Economic Consequences of Pregnancy Loss in Beef Cattle

Journal of Animal Science ◽

10.1093/jas/skaa278.226 ◽

2020 ◽

Vol 98 (Supplement_4) ◽

pp. 124-124

Author(s):

Vitor R G Mercadante ◽

Nicholas W Dias ◽

Claire L Timlin ◽

Stefania Pancini

Keyword(s):

United States ◽

Beef Cattle ◽

Pregnancy Rate ◽

Breeding Season ◽

Artificial Insemination ◽

Pregnancy Loss ◽

Production Systems ◽

The United States ◽

Pregnancy Diagnosis ◽

Cow Calf

Abstract Over the last four decades, several advances in reproductive biotechnologies have helped beef producers improve genetic traits of their cattle, tighten the breeding season and shorten the calving season, leading to an increase in overall profitability of cow-calf production systems. However, even with these advancements, reproductive failure and embryo mortality are still a major cause for economic loss in beef production. Recently, we projected a loss of $6.25 per exposed cow for every 1% decrease in pregnancy rate, with an estimated gross loss of $2.8 billion annually in the United States due to pregnancy failure in beef females. It is estimated that 75 to 80% of embryonic loss occurs by d 20 of gestation; a large portion of these losses occur during the first week of gestation and likely are caused by issues relating to fertilization failure, incompetence of embryos originated from poor quality oocytes and suboptimal uterine conditions. Furthermore, within the first month of gestation, nearly half of all cows submitted to breeding will not be pregnant 30 d later, and another 5% will lose their pregnancy by d 100 of gestation. In addition, breeding related costs, including bull purchase, breeding soundness exam, estrous synchronization, semen purchase, labor associated with artificial insemination and pregnancy diagnosis, are estimate at $65 per cow exposed. Assuming a 90% pregnancy rate at the end of the breeding season, and a scenario where all 30 million beef females in the U.S. are exposed to fixed-time artificial insemination and undergo one pregnancy diagnosis, the added lost revenue of not producing a live calf to sell at weaning and the cost of breeding, would represent a loss of over $21 billion annually in the United States. Strategies that reduce pregnancy loss in beef cattle are essential to improve productivity and profitability of cow-calf production systems.

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The effect of clitoral stimulation post artificial insemination on pregnancy rates of multiparous Bos indicus beef cows submitted to estradiol/progesterone-based estrus synchronization protocol

Journal of Animal Science ◽

10.1093/jas/skaa195 ◽

2020 ◽

Vol 98 (7) ◽

Author(s):

Ramiro V Oliveira Filho ◽

Reinaldo F Cooke ◽

Gustavo A de Mello ◽

Victor M Pereira ◽

Jose Luiz M Vasconcelos ◽

...

Keyword(s):

Pregnancy Rate ◽

Artificial Insemination ◽

Body Condition Score ◽

Bos Indicus ◽

Fixed Time ◽

Beef Cows ◽

Pregnancy Rates ◽

Estrus Synchronization ◽

Exit Velocity ◽

Clitoral Stimulation

Abstract Clitoral stimulation after artificial insemination (AI) in beef cattle is a common practice utilized by AI technicians; however, the effect of clitoral stimulation during fixed-time AI (TAI) is still unknown. The objective of the present experiment was to evaluate the effect of clitoral stimulation on temperament responses and pregnancy rates to TAI in Bos indicus beef cows. A total of 1,186 multiparous Nellore cows across three different locations were assigned to an estradiol/progesterone-based estrus synchronization + TAI protocol (day −11 to 0). Cows were randomly assigned to receive either 3 s of clitoral stimulation (n = 602) or no clitoral stimulation (n = 584) immediately after TAI (day 0). Cow body condition score (BCS) was recorded on day −11. Estrus expression was evaluated based on estrus detection visual aid patch activation on day 0 (estrus, ≥50% activated; no estrus, <50% activated). Temperament was assessed by individual chute score based on a 5-point scale before TAI, and individual exit velocity was measured after clitoral stimulation. Pregnancy diagnosis was performed 30 d after TAI via transrectal ultrasonography. Pregnancy rate to TAI was positively affected by BCS (P < 0.01) and estrus expression (P = 0.03). Pregnancy rates of cows receiving clitoral stimulation did not differ (P = 0.39) from cows non-stimulated (47.5 ± 4.6% vs. 44.3 ± 4.6%, respectively). No interaction of clitoral stimulation and estrus expression was observed (P = 0.26). Chute score was positively correlated to exit velocity (P < 0.01; r = 0.29); however, clitoral stimulation did not affect exit velocity (P = 0.86). In summary, pregnancy rates to TAI are influenced by various factors and multiple strategies have the potential to increase the fertility of beef cows submitted to TAI; however, clitoral stimulation of Bos indicus beef cows did not improve TAI pregnancy rate.

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Pengaruh Pemberian GnRH pada Sapi Potong yang Mengalami Kawin Berulang (Repeat Breeding)

Jurnal Sain Veteriner ◽

10.22146/jsv.62761 ◽

2021 ◽

Vol 39 (1) ◽

pp. 79

Author(s):

Surya Agus Prihatno ◽

Sri Gustari ◽

Asmarani Kusumawati ◽

Agung Budiyanto ◽

Erif Maha Nugraha Setyawan ◽

...

Keyword(s):

Statistical Analysis ◽

Beef Cattle ◽

Pregnancy Rate ◽

Artificial Insemination ◽

Control Group ◽

Chi Square ◽

Estrous Cycles ◽

The Third ◽

Significant Difference ◽

Gonadotrophin Releasing Hormone

Repeat breeding is a condition in which cows have normal estrous cycles and have been mated 3 times or more but are not pregnant. The incidence of repeat breeding in beef cattle can be detrimental to breeders in terms of time, that the calving period becomes longer so that the cows cannot give birth to calves once a year. Various ways to deal with repeat breeding have been done, but the results are not optimal. This study was conducted to determine the effect of Gonadotrophin Releasing Hormone (GnRH) in cows with repeat breeding. A total of fifteen beef cattle with repeat breeding were used in this study. The cows were divided into 3 groups of 5 each. Cows that were estrus in the first group (as a control group) were only performed artificial insemination (AI) without GnRH injection. In the second and third groups, after AI, they were injected with GnRH at AI time and 3-4 days after AI with a dose of 5 ml (Fertagyl®, 500 µg gonadorelin) intramuscularly. A pregnancy examination was carried out three months later and the results were recorded. The data obtained were analyzed descriptively and quantitatively using Chi-Square statistical analysis. The results of the analysis showed that there were differences in the pregnancy rate in the first group (control) with the second cow group and the third cow group, which were 20%, 80%, and 60% respectively. Based on statistical analysis, there was a significant difference in pregnancy rate (P <0.05) between the three groups. It was concluded that GnRH administration could increase the pregnancy rate in beef cattle that had repeat breeding.

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