Spelling suggestions: "subject:"estrus detection"" "subject:"astrus detection""
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Optimal time of insemination in dairy cattle identified in estrus by HeatWatchGrove, Mary Beth 29 August 2008 (has links)
Estrus detection programs practiced on most U.S. dairy farms are not intense enough to provide the information needed to accurately time insemination, thus preventing AI from obtaining its full conception rate potential. Herds (n = 17) participated in a trial designed to evaluate percent pregnant relative to various characteristics of estrus. Herds utilized HeatWatch® electronic estrus detection system to detect and record mounting activity for cows in estrus. Inseminations were performed daily during a three hour interval for all cows identified in estrus the previous 24 h. Model characterizing percent pregnant for cows (services = 2661) included effects of interval from first mount to AI (P < 0.01), mounts per estrus (P < 0.01), DIM at insemination (P < 0.01), herd (P <0.05), and season of AI (P < 0.05). As mounts per estrus and days in milk increased, percent diagnosed pregnant increased. Interval affected probability of pregnancy with highest odds ratios for percent pregnant occurring >4 to 16 h following onset of estrus. Model for heifers (n = 306) included linear effects of interval (P < 0.01), season (P < 0.05), and herd (P < 0.01). In dairy heifers, as interval from first mount to AI increased, percent pregnant decreased. Timing of insemination in dairy cows can now be performed relative to first mount of estrus, with highest probability of pregnancy occurring between >4 to 16 h after onset. If onset of estrus is not known, insemination should be performed at the next most convenient time within 3 h. / Master of Science
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ASSESSMENT OF THE TECHNICAL AND ECONOMIC POTENTIAL OF AUTOMATED ESTRUS DETECTION TECHNOLOGIES FOR DAIRY CATTLEDolecheck, Karmella Ann 01 January 2015 (has links)
Poor estrus detection can limit the reproductive performance of a dairy herd. One objective of this research was to evaluate an alternative method to traditional estrus detection in the form of automated monitoring technologies. To accomplish this, the first study considered the ability of automatically monitored parameters (activity, number of steps, lying bouts, lying time, feeding time, rumination time, and temperature) to detect estrus. A second study compared automated activity monitoring to timed artificial insemination as reproductive management strategies on commercial herds. The other objective of this research was to evaluate the economic potential of automated estrus detection technologies. This was accomplished by creating and evaluating a farm specific decision support tool to determine the net present value of adopting an automated estrus detection technology.
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Estratégias de manejo para aumentar a eficiência reprodutiva de bovinos leiteiros: protocolo de ciclo curto para a sincronização da ovulação e métodos auxiliares de detecção do estro / Strategies to improve reproductive efficiency in dairy cattle: use of a short cycle protocol for sunchronization of ovulation and auxiliary methods for estrus detectionSilva, Thiago Vilar 22 February 2016 (has links)
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Previous issue date: 2016-02-22 / Reproductive strategies are of great importance to reduce the operational cost of dairy farms.
Thus, different management models are developed to improve reproductive efficiency by
changes on nutrition, development of new protocols for synchronization of ovulation,
management strategies, or others. In this context, reproductive strategies in heifers has great
importance, as this category of animal represents most of the total costs of the farm. Another
critical point to the dairy farm is the estrus detection capability in lactating cows. According
to official surveys of the US government, the annual cost of poor estrus detection in dairy
cows is more than $ 300 million. Therefore, two studies were conducted: the first aimed to
evaluate the economic viability of the eight-day protocol to perform the first AI at the
beginning of the reproductive management against AI performed only after estrus detection in
dairy heifers. The results showed similar conception rates to those obtained after insemination
performed through visual estrus detection, resulting in reduced time to pregnancy, and thus
lower cost with feeding; The second study was conducted to verify the sensitivity, specificity,
positive predictive value, negative predictive value and accuracy of the two mainly methods
used for estrus detection in dairy cows of high production: tail painting and pedometer
system. It was observed with the second study that good estrus detection rates can be obtained
using both methods but the automated system performs better detection. Variables such as
body condition score, number of lactation, parity and milk production if incorporated into
estrus prediction model can increase the accuracy of detection of estrus by the device. / Estratégias reprodutivas são de grande importância para reduzir o custo operacional das
fazendas leiteiras. Dessa forma, diferentes modelos de manejo são desenvolvidos a fim de
melhorar a eficiência reprodutiva, seja por meio da nutrição, pelo desenvolvimento de novos
protocolos de sincronização da ovulação, estratégias de manejo ou outros. Nesse contexto, as
estratégias reprodutivas em novilhas ganham destacado interesse, pois essa categoria animal
representa grande parte dos custos totais da fazenda. Outro ponto crítico ao sistema se trata da
capacidade de detecção do estro em vacas lactantes. Segundo levantamentos oficiais do
governo dos Estados Unidos, o custo anual com a má detecção do estro em vacas leiteiras é de
mais de 300 milhões de dólares. Sendo assim, foram conduzidos dois estudos: o primeiro
objetivou avaliar a viabilidade econômica do uso do protocolo de oito dias na primeira IA, ao
início do manejo reprodutivo de novilhas, objetivando reduzir o tempo ao primeiro parto, e
assim reduzir o custo da alimentação com a categoria. Os resultados demonstraram taxas de
concepção similares às obtidas após a inseminação realizada com a detecção visual do estro,
reduzindo o tempo à prenhez, e assim diminuindo o custo com a alimentação; o segundo
estudo foi realizado para constatar a sensibilidade, especificidade, valor preditivo positivo,
valor preditivo negativo e acurácia dos dois principais métodos auxiliares utilizados na
detecção de estro em vacas leiteiras de alta produção: o método da pintura de cauda e o
sistema de pedômetro. Observou-se com o segundo estudo que boas taxas de detecção de
estro podem ser obtidas com a utilização de ambos os métodos, mas o sistema automatizado
apresenta melhores resultados de detecção. Variáveis tais como o escore de condição
corporal, número de lactações, paridade e produção de leite, se incorporadas ao modelo de
predição de estro, podem aumentar a acurácia de detecção de estro pelo dispositivo.
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Evaluation of the effects of a contract breeding program on reproductive efficiency in Ohio dairy herdsMeadows, Cheyney 14 July 2005 (has links)
No description available.
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Comparação de métodos auxiliares na identificação de estros em vacas e novilhas mestiças leiteirasBonato, Gabriela Lucia 04 June 2012 (has links)
The objective of this study was to evaluate the efficiency of auxiliary tools for the detection of estrus in cows. In experiment 1, we evaluated the efficiency of Estrotect ® in comparison with visual observation in 58 crossbred cows. The animals were divided into two groups: the TAI (n = 21) was subjected to a protocol of a fixed timed insemination (TAI) and 10 days after insemination device was fixed to the animals. In the group PG (n = 37) was administered prostaglandin (Dinoprost Tromethamine, Lutalyse ®, Pfizer) and immediately 25mg/animal/IM pasted adhesive. In the experiment 2, aimed to compare the Estrotect ® with chalk marker in crossbred heifers. After synchronization of estrus with P4 (CIDR) + GnRH - 7 days - PGF2a, heifers were randomly divided into two groups: Group 1 (n = 56) received the Estrotect ® and Group 2 (n = 56) received in the insertion of the marking tail with the chalk marker. The visual detection of estrus was performed daily in the same way in first experiment, from 07:00 to 08:00 and from 17:00 until 18:00. In experiment 2, the devices were only reached two times a day. After detection were artificially inseminated and diagnosed by ultrasound after 30 days in both estudies. In experiment 1, there was no effect of group (P> 0.05) on the efficiency of visual detection of estrus or auxiliary tool. There was no detectable difference between the efficiency of estrus and the visual detection device (P> 0.05) 92.5%. In experiment 2, not detected a group effect (P> 0.05) in the detection of estrus or the range of CIDR removal to the manifestation of estrus. The heat detection and conception rate was 92.86% (52/56), and 46,15% (24/52) for Estrotect® and 85,71% (48/56), and 58.33% (28/48) to chalk marker. It is concluded that the methods of estrus detection aids are effective and help in improving the efficiency of artificial insemination programs. / Objetivou-se neste estudo avaliar a eficiência de métodos auxiliares de detecção de estro em fêmeas bovinas. No experimento 1, avaliou-se a eficiência do Estrotect® em comparação com a observação visual em 58 vacas mestiças leiteiras. Os animais foram divididos em dois grupos: o grupo IATF (n= 21) foi submetido a um protocolo de inseminação artificial em tempo fixo (IATF) e 10 dias após a inseminação foi fixado o dispositivo nos animais. No grupo PG (n=37), foi administrado prostaglandina (Dinoprost Trometamina, Lutalyse®, Pfizer) 25mg/animal/IM e imediatamente colado o adesivo. No experimento 2, objetivou-se comparar o Estrotect® com o Bastão marcador em novilhas mestiças. Após a sincronização do estro com P4 (CIDR) + GnRH 7 dias - PGF2α, as novilhas foram divididas aleatoriamente em dois grupos: Grupo Estrotect (n = 56): recebeu o Estrotect® e Grupo Bastão marcador (n = 56): recebeu a marcação na inserção da cauda com o Bastão marcador. A detecção visual de estro foi realizada diariamente, apenas no experimento 1, das 07:00h às 08:00h e das 17:00h até 18:00h. No experimento 2 os dispositivos foram apenas checados duas vezes ao dia. Após detecção foram inseminadas artificialmente e diagnosticadas após 30 dias por ultrassonografia nos dois estudos. No experimento 1 não foi detectado efeito de grupo (P>0,05) na eficiência da detecção visual de estro ou do método auxiliar. Não foi detectado diferença entre a eficiência da detecção visual de estro e o dispositivo (P>0,05) 92,5%. No experimento 2, não foi detectado efeito de grupo (P>0,05) na detecção de estro nem no intervalo da retirada do CIDR até a manifestação do estro. A detecção de estro e a taxa de concepção foi de 92,86% (52/56) e 46,15%(24/52) para o Estrotect® e de 85,71% (48/56) e 58,33% (28/48) para o Bastão marcador. Conclui-se que os métodos auxiliares de detecção de estros são eficientes e ajudam na melhoria da eficiência dos programas de inseminação artificial. / Mestre em Ciências Veterinárias
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