RESUMO

Background: The enzootic bovine leukosis (EBL) is a viral disease with a chronic aspect and its etiological agent is anoncogenic deltaretrovirus called bovine leukemia virus (VLB). It has a wide distribution in dairy cattle herds, and it maytake several years before the first clinical manifestations occur. Animals seropositive for VLB are more susceptible todeveloping infectious diseases such as mastitis. The objective of this study was to evaluate the seroprevalence of EBL, theprevalence of mastitis, the possible association between leukosis and mastitis, and the risk factors related to leukosis inmunicipalities of the Caparaó region of Espírito Santo, Brazil.Materials, Methods & Results: The prevalence of enzootic bovine leukosis and its association with mastitis were evaluatedin an 854 clinically healthy crossbred (Bos tauros tauros x Bos taurus indicus) dairy cows were used, in different lactationphases, from farms located in the 12 municipalities that compose the Caparaó Capixaba micro-region, in the southernpart of Espírito Santo, Brazil, in the period from February to December 2015. The seroprevalence of EBL was determinedby the agar gel immunodiffusion test, the presence of clinical mastitis was ascertained by the black background mug testand of subclinical mastitis by the CMT. The reuse of needles, type of milking, reproductive management, calf mortality,presence of reproductive problems and milk yield were the risk factors assessed. The association between the variableswas estimated by the odds ratio (95% confidence interval). The significance of the associations was determined by theChi-square test. The prevalence of EBL, clinical and subclinical mastitis was 56.79%, 5.50% and 43.55%, respectively.There was a positive association between the EBL virus and the presence of...(AU)

Assuntos

RESUMO

This study evaluated the seroprevalence and associated factors of Infectious Bovine Rhinotracheitis (IBR) and Bovine Viral Diarrhea (BVD), and to analyze the possible relationship between IBR, BVD, and the occurrence of mastitis. For this purpose, 854 crossbred dairy cows were evaluated from 69 properties allocated in the 12 municipalities that make up the Caparaó region, Espírito Santo (ES), Brazil. The seroprevalence of IBR and BVD was determined using the indirect ELISA test. Associations between variables were estimated using the prevalence ratio (PR) with a 95% confidence interval. The chi-square test was used to verify the significance of the associations (P < 0.05). The average prevalence of IBR and BVD was 48.59% and 26.46%, respectively. Animals seroreactive for IBR were more likely to develop subclinical mastitis (P < 0.01; PR: 1.27), and cows that were seroreactive for BVD were more likely to develop clinical mastitis (P < 0.01; PR: 2.24). Mechanical milking was considered a factor associated with IBR (P < 0.01; PR: 1.36) and BVD (P < 0.01; PR: 1.25). Reproductive management by natural breeding was considered a factor associated with IBR (P < 0.01; PR: 1.22). Animals seroreactive for BVD were more likely to develop reproductive problems (P < 0.01; PR: 1.34). It was concluded that the agents that cause IBR and BVD are widely disseminated in dairy cattle herds in the municipalities of the Caparaó region, ES, Brazil. The presence of IBR and BVD increased the chances of cows developing subclinical mastitis and clinical mastitis, respectively, and the cows that were mechanically milked were more likely to be seroreactive for IBR and BVD.

O objetivo do presente estudo foi avaliar a soroprevalência e os fatores de risco associados à Rinotraqueíte Infecciosa Bovina (IBR) e Diarreia Viral Bovina (BVD), e analisar a possível relação entre IBR, BVD e à ocorrência de mastite. Para tanto, foram avaliadas 854 vacas leiteiras mestiças de 69 propriedades localizadas nos 12 municípios que compõem a região do Caparaó, Espírito Santo (ES), Brasil. A soroprevalência de IBR e BVD foram determinadas pelo teste ELISA indireto. As associações entre variáveis ​​foram estimadas pela razão de prevalência (PR) com intervalo de confiança de 95%. O teste do qui-quadrado foi utilizado para verificar a significância das associações (P < 0,05). A prevalência média de IBR e BVD foi de 48% e 26%, respectivamente. Os animais sororreagentes para IBR foram mais propensos a desenvolver mastite subclínica (P < 0,01; PR: 1,27), e as vacas sororreagentes para BVD foram mais propensas a desenvolver mastite clínica (P < 0,01; PR: 2,24). À ordenha mecânica foi considerada um fator associado a IBR (P < 0,01; PR: 1,36) e BVD (P < 0,01; PR: 1,25). O manejo reprodutivo por monta natural foi considerado um fator associado IBR (P < 0,01; PR: 1,22). Os animais sororreagentes para BVD foram mais propensos a desenvolverem problemas reprodutivos (P < 0,01; PR: 1,34). Concluiu-se que os agentes causadores de IBR e BVD estão amplamente disseminados em rebanhos leiteiros nos municípios da região de Caparaó, ES, Brasil. A presença de IBR e BVD aumentaram as chances das vacas desenvolverem mastite subclínica e mastite clínica, respectivamente, e as vacas que foram ordenhadas mecanicamente apresentaram maior probabilidade de serem sororreagente para IBR e BVD.

Assuntos

RESUMO

Background: The enzootic bovine leukosis (EBL) is a viral disease with a chronic aspect and its etiological agent is anoncogenic deltaretrovirus called bovine leukemia virus (VLB). It has a wide distribution in dairy cattle herds, and it maytake several years before the first clinical manifestations occur. Animals seropositive for VLB are more susceptible todeveloping infectious diseases such as mastitis. The objective of this study was to evaluate the seroprevalence of EBL, theprevalence of mastitis, the possible association between leukosis and mastitis, and the risk factors related to leukosis inmunicipalities of the Caparaó region of Espírito Santo, Brazil.Materials, Methods & Results: The prevalence of enzootic bovine leukosis and its association with mastitis were evaluatedin an 854 clinically healthy crossbred (Bos tauros tauros x Bos taurus indicus) dairy cows were used, in different lactationphases, from farms located in the 12 municipalities that compose the Caparaó Capixaba micro-region, in the southernpart of Espírito Santo, Brazil, in the period from February to December 2015. The seroprevalence of EBL was determinedby the agar gel immunodiffusion test, the presence of clinical mastitis was ascertained by the black background mug testand of subclinical mastitis by the CMT. The reuse of needles, type of milking, reproductive management, calf mortality,presence of reproductive problems and milk yield were the risk factors assessed. The association between the variableswas estimated by the odds ratio (95% confidence interval). The significance of the associations was determined by theChi-square test. The prevalence of EBL, clinical and subclinical mastitis was 56.79%, 5.50% and 43.55%, respectively.There was a positive association between the EBL virus and the presence of...

Assuntos

RESUMO

This study evaluated the seroprevalence and associated factors of Infectious Bovine Rhinotracheitis (IBR) and Bovine Viral Diarrhea (BVD), and to analyze the possible relationship between IBR, BVD, and the occurrence of mastitis. For this purpose, 854 crossbred dairy cows were evaluated from 69 properties allocated in the 12 municipalities that make up the Caparaó region, Espírito Santo (ES), Brazil. The seroprevalence of IBR and BVD was determined using the indirect ELISA test. Associations between variables were estimated using the prevalence ratio (PR) with a 95% confidence interval. The chi-square test was used to verify the significance of the associations (P < 0.05). The average prevalence of IBR and BVD was 48.59% and 26.46%, respectively. Animals seroreactive for IBR were more likely to develop subclinical mastitis (P < 0.01; PR: 1.27), and cows that were seroreactive for BVD were more likely to develop clinical mastitis (P < 0.01; PR: 2.24). Mechanical milking was considered a factor associated with IBR (P < 0.01; PR: 1.36) and BVD (P < 0.01; PR: 1.25). Reproductive management by natural breeding was considered a factor associated with IBR (P < 0.01; PR: 1.22). Animals seroreactive for BVD were more likely to develop reproductive problems (P < 0.01; PR: 1.34). It was concluded that the agents that cause IBR and BVD are widely disseminated in dairy cattle herds in the municipalities of the Caparaó region, ES, Brazil. The presence of IBR and BVD increased the chances of cows developing subclinical mastitis and clinical mastitis, respectively, and the cows that were mechanically milked were more likely to be seroreactive for IBR and BVD.(AU)

O objetivo do presente estudo foi avaliar a soroprevalência e os fatores de risco associados à Rinotraqueíte Infecciosa Bovina (IBR) e Diarreia Viral Bovina (BVD), e analisar a possível relação entre IBR, BVD e à ocorrência de mastite. Para tanto, foram avaliadas 854 vacas leiteiras mestiças de 69 propriedades localizadas nos 12 municípios que compõem a região do Caparaó, Espírito Santo (ES), Brasil. A soroprevalência de IBR e BVD foram determinadas pelo teste ELISA indireto. As associações entre variáveis ​​foram estimadas pela razão de prevalência (PR) com intervalo de confiança de 95%. O teste do qui-quadrado foi utilizado para verificar a significância das associações (P < 0,05). A prevalência média de IBR e BVD foi de 48% e 26%, respectivamente. Os animais sororreagentes para IBR foram mais propensos a desenvolver mastite subclínica (P < 0,01; PR: 1,27), e as vacas sororreagentes para BVD foram mais propensas a desenvolver mastite clínica (P < 0,01; PR: 2,24). À ordenha mecânica foi considerada um fator associado a IBR (P < 0,01; PR: 1,36) e BVD (P < 0,01; PR: 1,25). O manejo reprodutivo por monta natural foi considerado um fator associado IBR (P < 0,01; PR: 1,22). Os animais sororreagentes para BVD foram mais propensos a desenvolverem problemas reprodutivos (P < 0,01; PR: 1,34). Concluiu-se que os agentes causadores de IBR e BVD estão amplamente disseminados em rebanhos leiteiros nos municípios da região de Caparaó, ES, Brasil. A presença de IBR e BVD aumentaram as chances das vacas desenvolverem mastite subclínica e mastite clínica, respectivamente, e as vacas que foram ordenhadas mecanicamente apresentaram maior probabilidade de serem sororreagente para IBR e BVD.(AU)

Assuntos

RESUMO

ABSTRACT: This study evaluated the seroprevalence and associated factors of Infectious Bovine Rhinotracheitis (IBR) and Bovine Viral Diarrhea (BVD), and to analyze the possible relationship between IBR, BVD, and the occurrence of mastitis. For this purpose, 854 crossbred dairy cows were evaluated from 69 properties allocated in the 12 municipalities that make up the Caparaó region, Espírito Santo (ES), Brazil. The seroprevalence of IBR and BVD was determined using the indirect ELISA test. Associations between variables were estimated using the prevalence ratio (PR) with a 95% confidence interval. The chi-square test was used to verify the significance of the associations (P < 0.05). The average prevalence of IBR and BVD was 48.59% and 26.46%, respectively. Animals seroreactive for IBR were more likely to develop subclinical mastitis (P < 0.01; PR: 1.27), and cows that were seroreactive for BVD were more likely to develop clinical mastitis (P < 0.01; PR: 2.24). Mechanical milking was considered a factor associated with IBR (P < 0.01; PR: 1.36) and BVD (P < 0.01; PR: 1.25). Reproductive management by natural breeding was considered a factor associated with IBR (P < 0.01; PR: 1.22). Animals seroreactive for BVD were more likely to develop reproductive problems (P < 0.01; PR: 1.34). It was concluded that the agents that cause IBR and BVD are widely disseminated in dairy cattle herds in the municipalities of the Caparaó region, ES, Brazil. The presence of IBR and BVD increased the chances of cows developing subclinical mastitis and clinical mastitis, respectively, and the cows that were mechanically milked were more likely to be seroreactive for IBR and BVD.

RESUMO: O objetivo do presente estudo foi avaliar a soroprevalência e os fatores de risco associados à Rinotraqueíte Infecciosa Bovina (IBR) e Diarreia Viral Bovina (BVD), e analisar a possível relação entre IBR, BVD e à ocorrência de mastite. Para tanto, foram avaliadas 854 vacas leiteiras mestiças de 69 propriedades localizadas nos 12 municípios que compõem a região do Caparaó, Espírito Santo (ES), Brasil. A soroprevalência de IBR e BVD foram determinadas pelo teste ELISA indireto. As associações entre variáveis ​​foram estimadas pela razão de prevalência (PR) com intervalo de confiança de 95%. O teste do qui-quadrado foi utilizado para verificar a significância das associações (P < 0,05). A prevalência média de IBR e BVD foi de 48% e 26%, respectivamente. Os animais sororreagentes para IBR foram mais propensos a desenvolver mastite subclínica (P < 0,01; PR: 1,27), e as vacas sororreagentes para BVD foram mais propensas a desenvolver mastite clínica (P < 0,01; PR: 2,24). À ordenha mecânica foi considerada um fator associado a IBR (P < 0,01; PR: 1,36) e BVD (P < 0,01; PR: 1,25). O manejo reprodutivo por monta natural foi considerado um fator associado IBR (P < 0,01; PR: 1,22). Os animais sororreagentes para BVD foram mais propensos a desenvolverem problemas reprodutivos (P < 0,01; PR: 1,34). Concluiu-se que os agentes causadores de IBR e BVD estão amplamente disseminados em rebanhos leiteiros nos municípios da região de Caparaó, ES, Brasil. A presença de IBR e BVD aumentaram as chances das vacas desenvolverem mastite subclínica e mastite clínica, respectivamente, e as vacas que foram ordenhadas mecanicamente apresentaram maior probabilidade de serem sororreagente para IBR e BVD.

RESUMO

Avaliou-se a eficiência de dois indutores da ovulação: cipionato de estradiol (CE) e benzoato de estradiol (BE), na inseminação artificial em tempo fixo (IATF). Foram utilizadas 128 novilhas. Todos os animais foram submetidos ao mesmo protocolo de sincronização, a partir do dia 8 os animais foram distribuídos em dois tratamentos: Tratamento com CE no dia 8 (64 novilhas) e tratamento com BE no dia 9 (64 novilhas). Quanto ao número de folículos, só observou-se diferença significativa entre os tratamentos no dia 8. Não houve diferença (p>0,05) para taxa de crescimento folicular, diâmetro do folículo dominante (10,97 ± 1,24 e 9,77 ± 1,36 mm), e intervalo da ovulação à inseminação artificial (13,20 ± 3,79 e 23,00 ± 14,28 horas) entre os tratamentos. A retirada do dispositivo de progesterona à ovulação, em horas, foi de 60,60±3,69 e 74,75±15,17 horas, respectivamente para CE e BE (p 0,05). Houve diferença (p 0,05) entre os tratamentos para a taxa de ovulação, que foi de 90,00% e 40,00% para CE e BE, respectivamente. A taxa de prenhez foi de 37,3% (p0,05) para ambos tratamentos. A administração de CE no dia 8 possibilitou a redução de um manejo na IATF em novilhas sem influenciar na taxa de prenhez.(AU)

We evaluated the efficiency of two ovulation induction: estradiol cypionate (EC) and estradiol benzoate (EB), at fixed time artificial insemination (TAI). 128 heifers were used. All animals were subjected to the same synchronization protocol, from the 8th day animals were divided into two treatments: Treatment with CE on the 8th (64 heifers) and treatment with EB on Day 9 (64 heifers). Regarding the number of follicles, only there was a significant difference between treatments at day 8. There was no difference (p> 0.05) for follicular growth rate, diameter of the dominant follicle (10.97 ± 1.24 and 9, 77 ± 1.36 mm) and range of ovulation in artificial insemination (13.20 ± 3.79 and 23.00 ± 14.28 hours) between treatments. The withdrawal of progesterone device ovulation in hours was 60.60 ± 3.69 and 74.75 ± 15,17 hours respectively for CE and BE (p <0.05). There were differences (p <0.05) between treatments for ovulation rate, which was 90.00% and 40.00% for CE and BE, respectively. The pregnancy rate was 37.3% (p 0.05) for both treatments. The EC administration on 81 Centro enabled the reduction of management in the TAI in heifers without influencing pregnancy rate.(AU)

Se evaluó la eficiencia de la inducción de la ovulación de dos: cipionato de estradiol (CE) y benzoato de estradiol (EB), en la inseminación artificial de tiempo fijo (TAI). Se utilizaron 128 novillas. Todos los animales fueron sometidos al mismo protocolo de sincronización, a partir de los animales se dividieron en dos tratamientos 8º: El tratamiento con CE en la octava (64 novillas) y el tratamiento con EB en el Día 9 (64 novillas). En cuanto al número de folículos, solamente había una diferencia significativa entre los tratamientos en el día 8. No hubo diferencia (p> 0,05) para la tasa de crecimiento folicular, el diámetro del folículo dominante (10,97 ± 1,24 y 9, 77 ± 1,36 mm) y el rango de la ovulación en la inseminación artificial (13,20 ± 3,79 y 23,00 ± 14,28 horas) entre tratamientos. La retirada del dispositivo de progesterona ovulación en horas fue 60,60 ± 3,69 y 74,75 ± 15,17 horas, respectivamente, para el CE y BE (p <0,05). Hubo diferencias (p <0,05) entre los tratamientos para la tasa de ovulación, que fue 90,00% y 40,00% para CE y ser, respectivamente. La tasa de embarazo fue de 37,3% (p 0,05) en ambos tratamientos. La administración CE el 8 de activar la reducción de la gestión en el TAI en novillas sin influir en la tasa de embarazo.(AU)

Assuntos

RESUMO

Avaliou-se a eficiência de dois indutores da ovulação: cipionato de estradiol (CE) e benzoato de estradiol (BE), na inseminação artificial em tempo fixo (IATF). Foram utilizadas 128 novilhas. Todos os animais foram submetidos ao mesmo protocolo de sincronização, a partir do dia 8 os animais foram distribuídos em dois tratamentos: Tratamento com CE no dia 8 (64 novilhas) e tratamento com BE no dia 9 (64 novilhas). Quanto ao número de folículos, só observou-se diferença significativa entre os tratamentos no dia 8. Não houve diferença (p>0,05) para taxa de crescimento folicular, diâmetro do folículo dominante (10,97 ± 1,24 e 9,77 ± 1,36 mm), e intervalo da ovulação à inseminação artificial (13,20 ± 3,79 e 23,00 ± 14,28 horas) entre os tratamentos. A retirada do dispositivo de progesterona à ovulação, em horas, foi de 60,60±3,69 e 74,75±15,17 horas, respectivamente para CE e BE (p 0,05). Houve diferença (p 0,05) entre os tratamentos para a taxa de ovulação, que foi de 90,00% e 40,00% para CE e BE, respectivamente. A taxa de prenhez foi de 37,3% (p0,05) para ambos tratamentos. A administração de CE no dia 8 possibilitou a redução de um manejo na IATF em novilhas sem influenciar na taxa de prenhez.

We evaluated the efficiency of two ovulation induction: estradiol cypionate (EC) and estradiol benzoate (EB), at fixed time artificial insemination (TAI). 128 heifers were used. All animals were subjected to the same synchronization protocol, from the 8th day animals were divided into two treatments: Treatment with CE on the 8th (64 heifers) and treatment with EB on Day 9 (64 heifers). Regarding the number of follicles, only there was a significant difference between treatments at day 8. There was no difference (p> 0.05) for follicular growth rate, diameter of the dominant follicle (10.97 ± 1.24 and 9, 77 ± 1.36 mm) and range of ovulation in artificial insemination (13.20 ± 3.79 and 23.00 ± 14.28 hours) between treatments. The withdrawal of progesterone device ovulation in hours was 60.60 ± 3.69 and 74.75 ± 15,17 hours respectively for CE and BE (p <0.05). There were differences (p <0.05) between treatments for ovulation rate, which was 90.00% and 40.00% for CE and BE, respectively. The pregnancy rate was 37.3% (p 0.05) for both treatments. The EC administration on 81 Centro enabled the reduction of management in the TAI in heifers without influencing pregnancy rate.

Se evaluó la eficiencia de la inducción de la ovulación de dos: cipionato de estradiol (CE) y benzoato de estradiol (EB), en la inseminación artificial de tiempo fijo (TAI). Se utilizaron 128 novillas. Todos los animales fueron sometidos al mismo protocolo de sincronización, a partir de los animales se dividieron en dos tratamientos 8º: El tratamiento con CE en la octava (64 novillas) y el tratamiento con EB en el Día 9 (64 novillas). En cuanto al número de folículos, solamente había una diferencia significativa entre los tratamientos en el día 8. No hubo diferencia (p> 0,05) para la tasa de crecimiento folicular, el diámetro del folículo dominante (10,97 ± 1,24 y 9, 77 ± 1,36 mm) y el rango de la ovulación en la inseminación artificial (13,20 ± 3,79 y 23,00 ± 14,28 horas) entre tratamientos. La retirada del dispositivo de progesterona ovulación en horas fue 60,60 ± 3,69 y 74,75 ± 15,17 horas, respectivamente, para el CE y BE (p <0,05). Hubo diferencias (p <0,05) entre los tratamientos para la tasa de ovulación, que fue 90,00% y 40,00% para CE y ser, respectivamente. La tasa de embarazo fue de 37,3% (p 0,05) en ambos tratamientos. La administración CE el 8 de activar la reducción de la gestión en el TAI en novillas sin influir en la tasa de embarazo.

Assuntos

RESUMO

This study aimed to compare the efficiency and the cost of three protocols of timed artificial insemination (TAI) in dairy cows reared in extensive production system in the North and Northwest Fluminense regions. They used 162 crossbred cows Bos taurus taurus x Bos taurus indicus, otherwise healthy, previously assessed by ultrasound examination. It used commercial semen from different bulls properly tested in insemination centers. The cows received implants intravaginal progesterone and were submitted to the protocols: BE (n = 108) - estradiol benzoate; GnRH (n = 22) - estradiol benzoate and gonadotropin-releasing hormone (GnRH); and eCG (n = 32) - estradiol benzoate, GnRH and equine chorionic gonadotropin (eCG). After 45 days of TAI was performed ultrasound examination for the detection of pregnancy. Data were analyzed using the chi-square test. The cows submitted to BE protocols, GnRH and eCG obtained the pregnancy rates 42.6%, 45.5% and 68.8% respectively. The protocol showed lower economic cost was the BE, followed by eCG and last GnRH. The use of the TAI in the region can be a viable alternative to increase the reproductive rates in cattle herds, especially with the use of hormonal protocols that have in their composition eCG that, according to this study showed satisfactory pregnant rates and average economic cost.(AU)

O presente estudo objetivou comparar a eficiência e o custo de três protocolos de inseminação artificial em tempo fixo (IATF), em vacas leiteiras, criadas em sistema extensivo de produção nas regiões Norte e Noroeste Fluminense. Foram utilizadas 162 vacas mestiças Bos taurus taurus x Bos taurus indicus, hígidas, avaliadas previamente por exame de ultrassonografia. Foi utilizado sêmen comercial de diferentes touros devidamente testados nas centrais de inseminação. As vacas receberam implantes intravaginais de progesterona e foram submetidas aos protocolos: BE (n = 108) - benzoato de estradiol; GnRH (n = 22) - benzoato de estradiol e hormônio liberador de gonadotrofinas (GnRH); e eCG (n= 32) - benzoato de estradiol, GnRH e gonadotrofina coriônica equina (eCG). Decorridos 45 dias da IATF foi realizado exame de ultrassonografia para a detecção da gestação. Os dados foram analisados por meio do teste de qui-quadrado. As vacas submetidas aos protocolos BE, GnRH e eCG obtiveram os índices de prenhez 42,6%, 45,5% e 68,8% respectivamente. O protocolo que apresentou menor custo econômico foi o BE, seguido do eCG e por último o GnRH. O uso da IATF na região pode ser alternativa viável para incrementar os índices reprodutivos em rebanhos bovinos, sobretudo com uso de protocolos hormonais que tenham em sua composição a eCG que, segundo o presente estudo, apresentaram índices de prenhes satisfatórios e custo econômico mediano.(AU)

Assuntos

RESUMO

O presente estudo objetivou comparar a eficiência e o custo de três protocolos de inseminação artificial em tempo fixo (IATF), em vacas leiteiras, criadas em sistema extensivo de produção nas regiões Norte e Noroeste Fluminense. Foram utilizadas 162 vacas mestiças Bos taurus taurus x Bos taurus indicus, hígidas, avaliadas previamente por exame de ultrassonografia. Foi utilizado sêmen comercial de diferentes touros devidamente testados nas centrais de inseminação. As vacas receberam implantes intravaginais de progesterona e foram submetidas aos protocolos: BE (n = 108) - benzoato de estradiol; GnRH (n = 22) - benzoato de estradiol e hormônio liberador de gonadotrofinas (GnRH); e eCG (n= 32) - benzoato de estradiol, GnRH e gonadotrofina coriônica equina (eCG). Decorridos 45 dias da IATF foi realizado exame de ultrassonografia para a detecção da gestação. Os dados foram analisados por meio do teste de qui-quadrado. As vacas submetidas aos protocolos BE, GnRH e eCG obtiveram os índices de prenhez 42,6%, 45,5% e 68,8% respectivamente. O protocolo que apresentou menor custo econômico foi o BE, seguido do eCG e por último o GnRH. O uso da IATF na região pode ser alternativa viável para incrementar os índices reprodutivos em rebanhos bovinos, sobretudo com uso de protocolos hormonais que tenham em sua composição a eCG que, segundo o presente estudo, apresentaram índices de prenhes satisfatórios e custo econômico mediano.

This study aimed to compare the efficiency and the cost of three protocols of timed artificial insemination (TAI) in dairy cows reared in extensive production system in the North and Northwest Fluminense regions. They used 162 crossbred cows Bos taurus taurus x Bos taurus indicus, otherwise healthy, previously assessed by ultrasound examination. It used commercial semen from different bulls properly tested in insemination centers. The cows received implants intravaginal progesterone and were submitted to the protocols: BE (n = 108) - estradiol benzoate; GnRH (n = 22) - estradiol benzoate and gonadotropin-releasing hormone (GnRH); and eCG (n = 32) - estradiol benzoate, GnRH and equine chorionic gonadotropin (eCG). After 45 days of TAI was performed ultrasound examination for the detection of pregnancy. Data were analyzed using the chi-square test. The cows submitted to BE protocols, GnRH and eCG obtained the pregnancy rates 42.6%, 45.5% and 68.8% respectively. The protocol showed lower economic cost was the BE, followed by eCG and last GnRH. The use of the TAI in the region can be a viable alternative to increase the reproductive rates in cattle herds, especially with the use of hormonal protocols that have in their composition eCG that, according to this study showed satisfactory pregnant rates and average economic cost.

Assuntos