Effects of milking system in suckling period on growth, reproduction traits, and milk yield of East Friesian-cross dairy sheep

The main objective of this study was to determine the effects of milking system on growth, reproduction, and milk yield and composition of East Friesiancross (Tahirova) dairy sheep that were milked in the evening during the suckling period. A total of 43 Tahirova ewes and 58 lambs were used in the present study. One of the groups was milked in the evening (evening milked; EM) before coming together with their lambs, and the other group was not (not milked in the evening; NEM). Morning milking was performed in both groups during the study. Lambs in both groups were individually weaned at the age of 60 days. There was no statistical difference between the lambs' live weight at weaning in the EM and NEM groups, determined to be 23.46 and 24.11 kg, respectively. Live weight values of lambs were similar in the groups at ages of up to 180 days. The reproductive characteristics of ewe lambs in the EM and NEM groups, having similar growth rates and a similar live weight and body condition in the first estrus stages, were also similar. The return rate and frequency of return were close in both groups of ewe lambs. Milk yield of the NEM group was significantly higher than that of the EM group before and after weaning. However, in groups with similar lactation milk yield and length, the total marketable milk yield was higher in the suckling period of the EM group. The milking system in suckling period of Tahirova ewes does not significantly affect growth, average daily gain, and reproductive characteristics. Milk yield in the NEM group before and after weaning was significantly higher than the EM group, but the total marketable milk yield was higher in the EM group.(AU)

Clinical, sonographic and anatomopathological aspects of ovarian teratoma in a heifer / Aspectos clínicos, ultrassonográficos e anatomopatológicos do teratoma ovariano em uma novilha

Teratomas rarely occur in domestic species, especially in cattle. These tumors originate in fetal life and are characterized by rapid growth, which justifies their frequent detection in young animals. This study reported a case of ovarian teratoma in a heifer. On physical examination, the main signs identified were apathy, abdominal distention and tension, empty rumen, and mushy diarrhea. During rectal palpation, a mass was identified in the pelvic region, which was suggestive of cysts on ultrasound examination. The animal underwent laparotomy, followed by euthanasia due to a poor prognosis. At necropsy, a 54 x 43 x 52 cm (length x width x thickness) tumor was observed in the right ovary with multiple cystic areas, in addition to masses associated with multiple adhesions of the intestinal loops and peritonitis. On histopathology, muscle, cartilage, bone, nervous and epithelial tissue, glands, hair with follicles, were identified in the affected ovary. There was mixed inflammation and foci of necrosis observed with a complete absence of ovarian architecture in both the ovaries. Infiltrations were identified in the lymph nodes and mesenteric vessels. Glandular ducts were seen from the serosa to the intestinal mucosa. A locally infiltrative and expansile ovarian teratoma was diagnosed accordingly. It is considered that this kind of tumor can induce abdominal distension and absence of estrus in previously healthy, non-pregnant heifers.

Os teratomas são tumores raros nas espécies domésticas, sobretudo em bovinos. Esses tumores são caracterizados por crescimento rápido e origem durante a vida fetal, o que justifica seu diagnóstico frequente em animais jovens. O presente trabalho relata um caso de teratoma ovariano em uma novilha. No exame físico, os principais sinais identificados foram apatia, distensão e tensão abdominal, rúmen vazio e diarreia pastosa. Durante a palpação retal, uma massa foi identificada na região pélvica. Ao exame ultrassonográfico, a massa era sugestiva de cistos. O animal foi submetido a laparotomia, seguido de eutanásia devido ao mau prognóstico. Na necropsia foi observado um tumor de 54 x 43 x 52 cm (comprimento x largura x espessura) no ovário direito com múltiplas áreas císticas, além de massas associadas à múltiplas aderências das alças intestinais e peritonite. Na histopatologia foram identificados no ovário acometido a presença de tecidos muscular, cartilaginoso, ósseo, nervoso e epitelial, com glândulas, pelos e folículos. Havia inflamação mista e focos de necrose com ausência completa de arquitetura ovariana em ambos os ovários. Infiltrações foram identificadas em linfonodos e vasos mesentéricos. Ductos glandulares foram vistos desde a serosa até mucosa intestinal. Diagnosticou-se um teratoma ovariano localmente infiltrativo e expansivo. Considera-se que este tumor pode induzir distensão abdominal e ausência de estro em novilhas previamente sadias e não gestantes.

Previous sexual experience does not improve estrous behavior and ovulatory activity in seasonally anestrous goats in contact with photostimulated bucks

Sexually inexperienced ewes display lower estrous behavior during the first contact with rams. The objective of this study was to determine whether sexually inexperienced anestrous females display estrous behavior and ovulatory activity as the sexually experienced females, and with restricted sexual experience exposed to photo-stimulated bucks. Six bucks were rendered sexually active during the non-breeding season by exposure to artificially long days (16 h of light and 8 h of darkness per day) for 2.5 months. The first group, sexually experienced females (n = 10) had physical contact with two vasectomized bucks, and mating was allowed; the second group, with restricted sexual experience (n = 10) had contact with two vasectomized bucks through a wire-mesh fence and mating was prevented; the third group, sexually inexperienced females (n = 9) was totally isolated from bucks. At 14-month-old the females were exposed to photostimulated bucks for 15 days. The proportion of females that displayed estrous behavior, ovulations, short and normal ovulatory cycles, and pregnancy rates did not differ between sexually experienced, with restricted sexual experience, and sexually inexperienced (P > 0.05, in all variables). Similarly, the ovulation rate did not differ between the three groups of females (P > 0.05). However, the interval from introduction of the bucks to the first estrus was shorter in sexually inexperienced females (P < 0.05). Therefore, sexually inexperienced anestrous females displayed estrous behavior, ovulation, and pregnancy rate similar to those displayed by sexually experienced and with restricted sexual experience when exposed to photo-stimulated bucks through the male effect.(AU)

Previous sexual experience does not improve estrous behavior and ovulatory activity in seasonally anestrous goats in contact with photostimulated bucks

Sexually inexperienced ewes display lower estrous behavior during the first contact with rams. The objective of this study was to determine whether sexually inexperienced anestrous females display estrous behavior and ovulatory activity as the sexually experienced females, and with restricted sexual experience exposed to photo-stimulated bucks. Six bucks were rendered sexually active during the non-breeding season by exposure to artificially long days (16 h of light and 8 h of darkness per day) for 2.5 months. The first group, sexually experienced females (n = 10) had physical contact with two vasectomized bucks, and mating was allowed; the second group, with restricted sexual experience (n = 10) had contact with two vasectomized bucks through a wire-mesh fence and mating was prevented; the third group, sexually inexperienced females (n = 9) was totally isolated from bucks. At 14-month-old the females were exposed to photostimulated bucks for 15 days. The proportion of females that displayed estrous behavior, ovulations, short and normal ovulatory cycles, and pregnancy rates did not differ between sexually experienced, with restricted sexual experience, and sexually inexperienced (P > 0.05, in all variables). Similarly, the ovulation rate did not differ between the three groups of females (P > 0.05). However, the interval from introduction of the bucks to the first estrus was shorter in sexually inexperienced females (P < 0.05). Therefore, sexually inexperienced anestrous females displayed estrous behavior, ovulation, and pregnancy rate similar to those displayed by sexually experienced and with restricted sexual experience when exposed to photo-stimulated bucks through the male effect.

Influence of male on estrus behavior, estradiol and progesterone release and puberty onset on prepubertal Saanen goats / Influência do reprodutor sobre o comportamento de estro, liberação de estrógeno, progesterona e início da puberdade em cabras Saanen pré-puberes

The present study investigated the male effect on the estrus behaviors, estradiol and progesterone release in prepubertal Saanen goats. Twenty-nine female Saanen goats at 135 ± 10 days old with body weight of 22.8 ± 3.3 Kg were randomly assigned to three treatments: exposure to sexually active male (male treatment), exposure to androgenized females (androgenized female treatment), and prepubertal goats isolated from active male and androgenized females (control treatment). Sexual behaviors associated with estrus were recorded daily, and blood samples were taken weekly to determine estradiol and progesterone concentrations over 24 weeks. The experimental goats subjected to male or androgenized female had significantly higher frequency of estrus (mount acceptance) (P ≤ 0,02), progesterone (P ≤ 0,01), and estradiol (P ≤ 0,01) release than the control goats. Furthermore, goats exposed to a male showed estrus behavior two weeks earlier and maintained this estrus behavior for three weeks more than goats of both female and control treatments. Estrus was observed in 70 % of goats in male and female treatments during the breeding season versus 44 % of the control goats. Finally, significantly more goats subjected to male treatment (60 % of goats) showed progesterone concentrations higher than 1 ng mL-1 (which indicates the presence of a functional corpus luteum) compared to the female and control treatment (40 and 22 % of goats, respectively). These results shows that male treatment significantly increased the number of females showing estrus behavior, estradiol and progesterone release, and the number of animals with a functional corpus luteum, anticipating puberty for experimental goats, suggesting that the male effect could be used to anticipate the onset of puberty in goats.(AU)

O presente estudo investigou o efeito do macho sobre o comportamento do estro, liberação de estradiol e progesterona em cabritas Sannen pré-púberes. Vinte e nove cabritas com 135 ± 10 dias de idade e peso corporal de 22,8 ± 3,3 kg foram submetidas à três tratamentos: macho; fêmeas androgenizadas; controle (mantidas isoladas do efeito macho ou de fêmeas androgenizadas) . Os comportamentos sexuais foram registrados diariamente e as amostras de sangue foram colhidas semanalmente ao longo de 24 semanas. Os tratamentos macho e fêmea androgenizada aumentaram significativamente a ocorrência comportamental do estro (P ≤ 0,02), a concentração de progesterona (P ≤ 0,01) e estradiol (P ≤ 0,01) em comparação ao tratamento controle. As cabritas expostas ao efeito macho anteciparam o comportamento de estro em duas semanas, e o mantiveram por mais três semanas quando comparado às cabritas dos tratamentos fêmea androgenizada e controle. Apenas 44% das cabritas controle foram observadas em estro, sendo que 70% das cabritas submetidas aos tratamentos macho e fêmea androgenizada foram observadas em estro. Além disso, 60% das cabritas expostas ao efeito macho, 40 % das cabritas expostas ao efeito fêmea androgenizada e 22% das cabritas controle apresentaram concentrações de progesterona superiores a 1 ng mL-1, o que indica a presença de corpo lúteo funcional. De fato, o efeito macho aumentou significativamente o número de fêmeas em estro, a concentração de estradiol e progesterona, o número de fêmeas com corpo lúteo funcional, sugerindo que o efeito macho pode ser usado para antecipar o início da puberdade em cabritas Saanen.(AU)

Avaliação do uso do CIDR novo e reutilizado no início e duração do estro em ovinos / Evaluation of the use of new and reused CIDR at the beginning and duration of estrus in sheep

Study evaluated the use of new and re-utilized CIDR® to increase the reproductive breeding efficiency of the Santa Inês (SI) and Morada Nova (MN). In the synchronization protocol, 40 sheep was divided into four groups: MN with re-utilized CIDR®; MN with new CIDR®; SI with re-utilized CIDR® and SI with new CIDR®. The protocollasted for 15 days. At D0, females received CIDR®. Between D7 and D9, ovarian superstimulation was inducedby two doses application with a 12-hour break of p-FSH. Estrus confirmation was evaluated with ruffians, and the duration determined with the first and last mounts. The ovulation was determined by B-mode ultrasound and color Doppler. All animals of the experiment showed signs of estrus after removal of the device and there was no difference between treatments (p>0.05). In Treatment 1 (T1, CIDR® used), the beginning of estrus was 22.3±1.53h and in Treatment 2 (T2, new CIDR®) was 22.9±1.64h. In estrus duration, T1 and T2 was similar (21.6±1.81 and 22.2±0.63, respectively). Conclusion: the treatments are efficient to induce and synchronize estrus, with satisfactory results in their duration.

Avaliação do uso do CIDR novo e reutilizado no início e duração do estro em ovinos / Evaluation of the use of new and reused CIDR at the beginning and duration of estrus in sheep

Study evaluated the use of new and re-utilized CIDR® to increase the reproductive breeding efficiency of the Santa Inês (SI) and Morada Nova (MN). In the synchronization protocol, 40 sheep was divided into four groups: MN with re-utilized CIDR®; MN with new CIDR®; SI with re-utilized CIDR® and SI with new CIDR®. The protocollasted for 15 days. At D0, females received CIDR®. Between D7 and D9, ovarian superstimulation was inducedby two doses application with a 12-hour break of p-FSH. Estrus confirmation was evaluated with ruffians, and the duration determined with the first and last mounts. The ovulation was determined by B-mode ultrasound and color Doppler. All animals of the experiment showed signs of estrus after removal of the device and there was no difference between treatments (p>0.05). In Treatment 1 (T1, CIDR® used), the beginning of estrus was 22.3±1.53h and in Treatment 2 (T2, new CIDR®) was 22.9±1.64h. In estrus duration, T1 and T2 was similar (21.6±1.81 and 22.2±0.63, respectively). Conclusion: the treatments are efficient to induce and synchronize estrus, with satisfactory results in their duration.(AU)

Indução do estro em cutias (Dasyprocta leporina) utilizando-se protocolos à base de prostaglandina isolada ou em associação com análogo de GnRH / Estrus induction in agoutis (Dasyprocta leporina) using protocols based on prostaglandin isolated or in association to GnRH analogue

Comparou-se a eficiência de protocolos para indução de estro em cutias. Em cinco fêmeas, foram administradas duas doses de cloprostenol (5µg) com intervalo de nove dias, via intraperitoneal; em outras cinco, administraram-se 30µg de análogo do hormônio liberador de gonadotrofinas (GnRH), via intravulvar, seguidos de 5µg de cloprostenol, via intraperitoneal, após sete dias e, após mais dois dias, nova dose do análogo de GnRH. A cada três dias, a ciclicidade reprodutiva dos animais foi monitorada, por meio de coleta de sangue, para dosagem hormonal, ultrassonografia ovariana e citologia vaginal. Duas das fêmeas que receberam apenas prostaglandina, as quais estavam em fase luteal no início do tratamento, manifestaram o estro aos três e seis dias após a segunda administração da droga. Já nas fêmeas que receberam a prostaglandina associada ao análogo do GnRH, duas que originalmente estavam em fase luteal apresentaram estro aos quatro dias após o tratamento, e uma outra apenas após 10 dias. Não foram evidenciadas diferenças estatísticas quanto à eficiência dos tratamentos (P>0,05). Conclui-se que, de acordo com os protocolos utilizados, o uso da prostaglandina isolada ou em associação com análogo do GnRH para a indução do estro em cutias D. leporina apresenta eficiência limitada às fêmeas que estejam em fase luteal por ocasião do início do tratamento.(AU)

We compared the efficiency of protocols for estrus induction in agoutis. Five females received double intraperitoneal administration of cloprostenol (5µg) on a 2-days interval; other five females were treated with intravulvar administration of 30µg gonadotrophin release hormone analogue (GnRH associated to intraperitoneal administration of 5µg cloprostenol after seven days and a new administration of GnRH analogue after two days. Every 3 days, the agoutis' reproductive cycle was monitored by blood collection for hormonal analysis, ovarian ultrasound and vaginal cytology. Two females, originally in luteal phase, that received isolated prostaglandin presented estrous signs at 3 and 6 days after the second drug administration. From the females that received the association, two that were originally in luteal phase presented estrus at 4 days after treatment, and one other presented estrus only after 10 days. There was no significant statistical difference regarding the efficiency of treatments for estrus induction (P>0.05). We conclude that, according to the protocols tested in the study, the use of isolated prostaglandin or its association to GnRH analogue for estrus induction in D. leporine shows an efficiency limited to the females that were in luteal phase in the beginning of the treatment.(AU)

Indução do estro em cutias (Dasyprocta leporina) utilizando-se protocolos à base de prostaglandina isolada ou em associação com análogo de GnRH / Estrus induction in agoutis (Dasyprocta leporina) using protocols based on prostaglandin isolated or in association to GnRH analogue

Comparou-se a eficiência de protocolos para indução de estro em cutias. Em cinco fêmeas, foram administradas duas doses de cloprostenol (5µg) com intervalo de nove dias, via intraperitoneal; em outras cinco, administraram-se 30µg de análogo do hormônio liberador de gonadotrofinas (GnRH), via intravulvar, seguidos de 5µg de cloprostenol, via intraperitoneal, após sete dias e, após mais dois dias, nova dose do análogo de GnRH. A cada três dias, a ciclicidade reprodutiva dos animais foi monitorada, por meio de coleta de sangue, para dosagem hormonal, ultrassonografia ovariana e citologia vaginal. Duas das fêmeas que receberam apenas prostaglandina, as quais estavam em fase luteal no início do tratamento, manifestaram o estro aos três e seis dias após a segunda administração da droga. Já nas fêmeas que receberam a prostaglandina associada ao análogo do GnRH, duas que originalmente estavam em fase luteal apresentaram estro aos quatro dias após o tratamento, e uma outra apenas após 10 dias. Não foram evidenciadas diferenças estatísticas quanto à eficiência dos tratamentos (P>0,05). Conclui-se que, de acordo com os protocolos utilizados, o uso da prostaglandina isolada ou em associação com análogo do GnRH para a indução do estro em cutias D. leporina apresenta eficiência limitada às fêmeas que estejam em fase luteal por ocasião do início do tratamento.(AU)

We compared the efficiency of protocols for estrus induction in agoutis. Five females received double intraperitoneal administration of cloprostenol (5µg) on a 2-days interval; other five females were treated with intravulvar administration of 30µg gonadotrophin release hormone analogue (GnRH associated to intraperitoneal administration of 5µg cloprostenol after seven days and a new administration of GnRH analogue after two days. Every 3 days, the agoutis' reproductive cycle was monitored by blood collection for hormonal analysis, ovarian ultrasound and vaginal cytology. Two females, originally in luteal phase, that received isolated prostaglandin presented estrous signs at 3 and 6 days after the second drug administration. From the females that received the association, two that were originally in luteal phase presented estrus at 4 days after treatment, and one other presented estrus only after 10 days. There was no significant statistical difference regarding the efficiency of treatments for estrus induction (P>0.05). We conclude that, according to the protocols tested in the study, the use of isolated prostaglandin or its association to GnRH analogue for estrus induction in D. leporine shows an efficiency limited to the females that were in luteal phase in the beginning of the treatment.(AU)

Parâmetros reprodutivos após indução de estro com diferentes intervalos de permanência do dispositivo vaginal em cabras Toggenburg acíclicas / Reproductive parameters after induction of estrus with different ranges of the vaginal device in acyclic Toggenburg goats

Este estudo objetivou avaliar o comportamento sexual e a dinâmica ovulatória de cabras da raça Toggenburg após a indução do estro com dispositivo intravaginal de progesterona durante seis, nove e 12 dias de permanência. No momento da inserção do dispositivo e 24 horas antes da retirada do dispositivo, foi administrado 5mg de dinoprost e 200UI de eCG, respectivamente. A dinâmica ovulatória foi acompanhada por ultrassonografia a cada oito horas, enquanto o estro foi observado a cada 12 horas. Todas as cabras apresentaram estro. O intervalo da retirada do dispositivo ao início do estro foi de 29,5 ± 9,6 para G6dias; 34,0 ± 6,0 e 32,4 ± 7,7h, G9dias e G12dias, respectivamente. Igualmente, foi encontrada diferença (P<0,05) entre o G6dias e os outros grupos. A duração do estro diferiu (P<0,05) entre o G6dias (36,0 ± 12,6) e os outros dois grupos (G9dias: 31,2 ± 14,3; G12dias: 33,4 ± 8,6). A taxa de ovulação (81%; 89,5% e; 71,4%), intervalo da retirada do dispositivo à ovulação (50,5 ± 11,4; 46,3 ± 5,9 e; 46,7 ± 8,3), diâmetro do maior folículo (6,6 ± 0,3; 6,6 ± 0,9 e; 6,9 ± 0,8) diâmetro do segundo maior folículo (6,4 ± 0,7; 6,6 ± 0,8 e; 6,8 ± 0,6) e o número de folículos ovulados (1,5 ± 0,6; 1,7 ± 0,6 e 2,0 ± 0,9) para G6dias, G9dias e G12dias, respectivamente, foram semelhantes (P>0,05). Todos os protocolos foram eficientes em induzir o estro sincronizado em cabras da raça Toggenburg, trabalhando em conjunto com a eficiência reprodutiva e produtiva desses animais.(AU)

This study aimed to evaluate the sexual behavior and the ovulatory dynamics of Toggenburg goats after induction of synchronized estrus by an intravaginal progesterone device for six, nine and twelve days. At the device insertion and 24 h before the device removal, 5mg of dinoprost and 200 UI of eCG was administered, respectively. The ovulatory dynamics was assessed by ultrasound every 8 h, while the sexual behavior was observed every 12 h. All goats showed estrus. The intervals from device removal to estrus were 29.5 ± 9.7, 34.0 ± 6.0 and 32.4 ± 7.7h to G6days, G9days and G12days, respectively. Iqually, it was found difference (P<0.05) among G6days and the other groups. The duration of estrus differed (P<0.05) among the G6days (36.0 ± 12.6) and the other two groups (G9days: 31.2 ± 14.3; G12days: 33.4 ± 8.6). The ovulation rate (81.0%; 89.5% and; 71.4%); the interval from device removal to ovulation (50.5 ± 11.4; 46.3 ± 5.9 and; 46.7 ± 8.3), the diameter of the largest follicle (6.6 ± 0.3; 6.6 ± 0.9 and; 6.9 ± 0.8), diameter of the second largest follicle (6.4 ± 0.7; 6.6 ± 0.8 and; 6.8 ± 0.6) and the number of ovulations (1.5 ± 0.6; 1.7 ± 0.6 and; 2.0 ± 0.9) for G6days, G9days and G12days, respectively, were similar (P>0.05). All treatments were effective for the induction of synchronized estrus in Toggenburg goats, working jointly with the reproductive and productive efficiency of these animals.(AU)

Parâmetros reprodutivos após indução de estro com diferentes intervalos de permanência do dispositivo vaginal em cabras Toggenburg acíclicas / Reproductive parameters after induction of estrus with different ranges of the vaginal device in acyclic Toggenburg goats

Este estudo objetivou avaliar o comportamento sexual e a dinâmica ovulatória de cabras da raça Toggenburg após a indução do estro com dispositivo intravaginal de progesterona durante seis, nove e 12 dias de permanência. No momento da inserção do dispositivo e 24 horas antes da retirada do dispositivo, foi administrado 5mg de dinoprost e 200UI de eCG, respectivamente. A dinâmica ovulatória foi acompanhada por ultrassonografia a cada oito horas, enquanto o estro foi observado a cada 12 horas. Todas as cabras apresentaram estro. O intervalo da retirada do dispositivo ao início do estro foi de 29,5 ± 9,6 para G6dias; 34,0 ± 6,0 e 32,4 ± 7,7h, G9dias e G12dias, respectivamente. Igualmente, foi encontrada diferença (P<0,05) entre o G6dias e os outros grupos. A duração do estro diferiu (P<0,05) entre o G6dias (36,0 ± 12,6) e os outros dois grupos (G9dias: 31,2 ± 14,3; G12dias: 33,4 ± 8,6). A taxa de ovulação (81%; 89,5% e; 71,4%), intervalo da retirada do dispositivo à ovulação (50,5 ± 11,4; 46,3 ± 5,9 e; 46,7 ± 8,3), diâmetro do maior folículo (6,6 ± 0,3; 6,6 ± 0,9 e; 6,9 ± 0,8) diâmetro do segundo maior folículo (6,4 ± 0,7; 6,6 ± 0,8 e; 6,8 ± 0,6) e o número de folículos ovulados (1,5 ± 0,6; 1,7 ± 0,6 e 2,0 ± 0,9) para G6dias, G9dias e G12dias, respectivamente, foram semelhantes (P>0,05). Todos os protocolos foram eficientes em induzir o estro sincronizado em cabras da raça Toggenburg, trabalhando em conjunto com a eficiência reprodutiva e produtiva desses animais.(AU)

This study aimed to evaluate the sexual behavior and the ovulatory dynamics of Toggenburg goats after induction of synchronized estrus by an intravaginal progesterone device for six, nine and twelve days. At the device insertion and 24 h before the device removal, 5mg of dinoprost and 200 UI of eCG was administered, respectively. The ovulatory dynamics was assessed by ultrasound every 8 h, while the sexual behavior was observed every 12 h. All goats showed estrus. The intervals from device removal to estrus were 29.5 ± 9.7, 34.0 ± 6.0 and 32.4 ± 7.7h to G6days, G9days and G12days, respectively. Iqually, it was found difference (P<0.05) among G6days and the other groups. The duration of estrus differed (P<0.05) among the G6days (36.0 ± 12.6) and the other two groups (G9days: 31.2 ± 14.3; G12days: 33.4 ± 8.6). The ovulation rate (81.0%; 89.5% and; 71.4%); the interval from device removal to ovulation (50.5 ± 11.4; 46.3 ± 5.9 and; 46.7 ± 8.3), the diameter of the largest follicle (6.6 ± 0.3; 6.6 ± 0.9 and; 6.9 ± 0.8), diameter of the second largest follicle (6.4 ± 0.7; 6.6 ± 0.8 and; 6.8 ± 0.6) and the number of ovulations (1.5 ± 0.6; 1.7 ± 0.6 and; 2.0 ± 0.9) for G6days, G9days and G12days, respectively, were similar (P>0.05). All treatments were effective for the induction of synchronized estrus in Toggenburg goats, working jointly with the reproductive and productive efficiency of these animals.(AU)

Calf presence and estrous response, ovarian follicular activity and the pattern of luteinizing hormone in postpartum Bos indicus cows

The main objective of the present experiment was to assess the effect of temporary weaning on the onset of estrus, ovarian follicular activity and secretion of luteinizing hormone in Bos indicus cows. Forty six mature cows were divided into three groups 1) calves were weaned for 72 h allowing auditory, olfactory and visual contact with their dams (VISUAL, n = 17), 2) calves without contact with their dams for 72 h (NC, n = 17) and 3) calves not weaned and in constant contact with their dams (CTRL, n = 12). Estrus was synchronized in all cows using CIDR for 9 days plus 2 mg of estradiol benzoate given at CIDR insertion. The VISUAL group had a greater (P < 0.05) proportion of cows in estrus (76.5%) compared to the CTRL group (16.7%), but no differences were found when compared to the NC group (58.8%). The VISUAL group had a greater proportion of animal that ovulated (76.5%) compared to CTRL (33.3%) and NC groups (64.7%; P = 0.059). Duration of estrus was shorter (P = 0.04) in the VISUAL (8.4 ± 4.4 hours) than in the NC (12.9 ± 13.4 hours) however, CTRL treatment (11 ± 1.4 hours) was not different from either of these two groups. LH concentration after implant removal was similar among treatments and started to increase at 36 h post CIDR removal. Only in the CTRL group was there an obvious increase by 54 h after implant removal. Follicular size increased in diameter from 36 h and were evident in treatments and control groups by 60 h (P < 0.05). The VISUAL treatment increased the number of cows ovulating and shortened the length of estrus. VISUAL and NC groups showed a similar response in follicular growth and pattern of circulating LH because of treatment.

Calf presence and estrous response, ovarian follicular activity and the pattern of luteinizing hormone in postpartum Bos indicus cows

The main objective of the present experiment was to assess the effect of temporary weaning on the onset of estrus, ovarian follicular activity and secretion of luteinizing hormone in Bos indicus cows. Forty six mature cows were divided into three groups 1) calves were weaned for 72 h allowing auditory, olfactory and visual contact with their dams (VISUAL, n = 17), 2) calves without contact with their dams for 72 h (NC, n = 17) and 3) calves not weaned and in constant contact with their dams (CTRL, n = 12). Estrus was synchronized in all cows using CIDR for 9 days plus 2 mg of estradiol benzoate given at CIDR insertion. The VISUAL group had a greater (P < 0.05) proportion of cows in estrus (76.5%) compared to the CTRL group (16.7%), but no differences were found when compared to the NC group (58.8%). The VISUAL group had a greater proportion of animal that ovulated (76.5%) compared to CTRL (33.3%) and NC groups (64.7%; P = 0.059). Duration of estrus was shorter (P = 0.04) in the VISUAL (8.4 ± 4.4 hours) than in the NC (12.9 ± 13.4 hours) however, CTRL treatment (11 ± 1.4 hours) was not different from either of these two groups. LH concentration after implant removal was similar among treatments and started to increase at 36 h post CIDR removal. Only in the CTRL group was there an obvious increase by 54 h after implant removal. Follicular size increased in diameter from 36 h and were evident in treatments and control groups by 60 h (P < 0.05). The VISUAL treatment increased the number of cows ovulating and shortened the length of estrus. VISUAL and NC groups showed a similar response in follicular growth and pattern of circulating LH because of treatment.(AU)

The effect of the intensity of estrus expression on the follicular diameter and fertility of Nellore cows managed under a FTAI program / Efeito da intensidade da expressão do estro no diâmetro folicular e na fertilidade de vacas Nelore submetidas a um programa de IATF

The aim of this study was to determine the relationship between the intensity of estrus expression on the ovulatory follicle diameter (OFD) and its effect on the conception rate in zebu females managed under a FTAI program. On a random day of the estrous cycle, day 0, 308 Nellore females received an intravaginal progesterone device and 2.0 mg of estradiol benzoate were administered intramuscularly (IM). On day 8, the progesterone device was removed, and 300 IU of equine chorionic gonadotropin, 150 g of d-cloprostenol, and 1.0 mg of estradiol cypionate were administered IM. The animals were then painted with animal marker spray between the sacral tuberosity and the tailhead. On day 10, the animals were categorized into three groups: no estrus expression (n = 78), low intensity of estrus expression (n = 66) and high intensity of estrus expression (n = 164). The OFD was then measured, and artificial insemination (AI) was performed. The results suggest that determining the intensity of estrus expression is a good parameter to identify females with greater follicular diameter and increased fertility in Nellore cows submitted to a FTAI protocol.

Este trabalho foi conduzido com o objetivo de verificar a relação da intensidade da expressão do estro sobre o diâmetro do folículo ovulatório e seu impacto sobre a taxa de concepção em fêmeas zebuínas submetidas a um programa de IATF. Em um dia aleatório do ciclo estral denominado D0, 308 fêmeas da raça Nelore receberam um dispositivo intravaginal de progesterona e foram administrados 2,0 mg de benzoato de estradiol intramuscular (IM). No D8, retirou-se o dispositivo de progesterona e foram aplicados 300UI de Gonadotrofina coriônica equina, 150 µg de d-Cloprostenol e 1,0 mg de cipionato de estradiol IM. Neste momento, os animais foram pintados com bastão marcador entre a tuberosidade sacral e a inserção da cauda. No D10, os animais foram caracterizados em três grupos: Grupo sem expressão do estro (n=78), Grupo baixa intensidade da expressão do estro (n=66) e Grupo alta intensidade da expressão do estro (n=164). Em seguida, procedeu-se à mensuração do diâmetro do folículo ovulatório e foi realizada a inseminação artificial. Os resultados sugerem que a detecção da intensidade da expressão do estro constitui um bom parâmetro para auxiliar na identificação de fêmeas com maior diâmetro folicular e elevada fertilidade em vacas Nelore submetidas a um protocolo de IATF.

The effect of the intensity of estrus expression on the follicular diameter and fertility of Nellore cows managed under a FTAI program / Efeito da intensidade da expressão do estro no diâmetro folicular e na fertilidade de vacas Nelore submetidas a um programa de IATF

The aim of this study was to determine the relationship between the intensity of estrus expression on the ovulatory follicle diameter (OFD) and its effect on the conception rate in zebu females managed under a FTAI program. On a random day of the estrous cycle, day 0, 308 Nellore females received an intravaginal progesterone device and 2.0 mg of estradiol benzoate were administered intramuscularly (IM). On day 8, the progesterone device was removed, and 300 IU of equine chorionic gonadotropin, 150 g of d-cloprostenol, and 1.0 mg of estradiol cypionate were administered IM. The animals were then painted with animal marker spray between the sacral tuberosity and the tailhead. On day 10, the animals were categorized into three groups: no estrus expression (n = 78), low intensity of estrus expression (n = 66) and high intensity of estrus expression (n = 164). The OFD was then measured, and artificial insemination (AI) was performed. The results suggest that determining the intensity of estrus expression is a good parameter to identify females with greater follicular diameter and increased fertility in Nellore cows submitted to a FTAI protocol.(AU)

Este trabalho foi conduzido com o objetivo de verificar a relação da intensidade da expressão do estro sobre o diâmetro do folículo ovulatório e seu impacto sobre a taxa de concepção em fêmeas zebuínas submetidas a um programa de IATF. Em um dia aleatório do ciclo estral denominado D0, 308 fêmeas da raça Nelore receberam um dispositivo intravaginal de progesterona e foram administrados 2,0 mg de benzoato de estradiol intramuscular (IM). No D8, retirou-se o dispositivo de progesterona e foram aplicados 300UI de Gonadotrofina coriônica equina, 150 µg de d-Cloprostenol e 1,0 mg de cipionato de estradiol IM. Neste momento, os animais foram pintados com bastão marcador entre a tuberosidade sacral e a inserção da cauda. No D10, os animais foram caracterizados em três grupos: Grupo sem expressão do estro (n=78), Grupo baixa intensidade da expressão do estro (n=66) e Grupo alta intensidade da expressão do estro (n=164). Em seguida, procedeu-se à mensuração do diâmetro do folículo ovulatório e foi realizada a inseminação artificial. Os resultados sugerem que a detecção da intensidade da expressão do estro constitui um bom parâmetro para auxiliar na identificação de fêmeas com maior diâmetro folicular e elevada fertilidade em vacas Nelore submetidas a um protocolo de IATF.(AU)

Role of male effect on reproductive efficiency of nulliparous Santa Inês and Morada Nova ewes raised in different regions / Ação do efeito macho sobre a eficiência reprodutiva de ovelhas nulíparas das raças Santa Inês e Morada Nova criadas em diferentes regiões

Background: The male effect is an attractive strategy to increase herd production by concentrating mating events and deliveries and further allowing the adoption of genetic improvement programs. It holds similar efficiency to those chemically based estrous synchronization methods, but has the advantage of being a natural method. The work was aimed to evaluate the influence of male effect on estrous induction and synchronization, pregnancy and prolificacy of nulliparous Santa Inês and Morada Nova ewes raised in Semiarid and Zona da Mata regions of Pernambuco state. Materials, Methods & Results: Santa Inês (n = 80) and Morada Nova (n = 80) females, with age from 11 to 12 months, after being evaluated and selected, were identified with plastic ear tags, weighted and maintained isolated from males, during 30 days before experiment onset, without any physical, visual, olfactive and auditive contact. Estrous events were observed twice a day (6:00 and 16:00 h) by trained personnel, during a breeding season of 60 days, and estrous were considered synchronized when detected, within first five days of breeding season. Rams of Santa Inês (n = 2) and Morada Nova (n = 2) breeds were selected based upon reproductive capacity by an andrology exam, and were marked on the externum bone region with a wax and ink (4:1) mixture, and were marked in female lots in order to identify females in [...](AU)

Role of male effect on reproductive efficiency of nulliparous Santa Inês and Morada Nova ewes raised in different regions / Ação do efeito macho sobre a eficiência reprodutiva de ovelhas nulíparas das raças Santa Inês e Morada Nova criadas em diferentes regiões

Background: The male effect is an attractive strategy to increase herd production by concentrating mating events and deliveries and further allowing the adoption of genetic improvement programs. It holds similar efficiency to those chemically based estrous synchronization methods, but has the advantage of being a natural method. The work was aimed to evaluate the influence of male effect on estrous induction and synchronization, pregnancy and prolificacy of nulliparous Santa Inês and Morada Nova ewes raised in Semiarid and Zona da Mata regions of Pernambuco state. Materials, Methods & Results: Santa Inês (n = 80) and Morada Nova (n = 80) females, with age from 11 to 12 months, after being evaluated and selected, were identified with plastic ear tags, weighted and maintained isolated from males, during 30 days before experiment onset, without any physical, visual, olfactive and auditive contact. Estrous events were observed twice a day (6:00 and 16:00 h) by trained personnel, during a breeding season of 60 days, and estrous were considered synchronized when detected, within first five days of breeding season. Rams of Santa Inês (n = 2) and Morada Nova (n = 2) breeds were selected based upon reproductive capacity by an andrology exam, and were marked on the externum bone region with a wax and ink (4:1) mixture, and were marked in female lots in order to identify females in [...]

Eficiência da inseminação artificial em tempo fixo (IATF) associada à detecção de estro por marcação da cauda e presença de muco vaginal no dia da inseminação em vacas Nelore / Efficiency of artificial inseminatio n in fixed time (FTAI) associated with estrus detection by marking the tail and the presence ofvaginal mucus on the day of insemination in Nelore cows

The objective of this study was to evaluate the efficiency of artificial insemination in fixed timeassociated with estrus detection in Nellore cows. They used 917 females, all submitted to estrus synchronizationprotocol and formed two groups: G1 (n = 489), marked on the back with fluorescent dye and then checked if thecroup was blurred or not, and had vaginal mucus or not and G2 (n = 428) were formed by females inseminatedonly synchronized. Pregnancy diagnosis was performed by ultrasound 30 days after insemination. In G1 and G2,pregnancy rates were, respectively, 46.01% and 41.12%. In G1, blurred females (52.19%), not blurred(21.78%), presence of mucus (62.57%) and no mucus (35.97%). Pregnancy rates did not differ between thegroups G1 and G2. In G1, blurred females or mucus had higher rates. It is concluded that the detection ofestrus, insemination favored the pregnancy rate.(AU)

Eficiência da inseminação artificial em tempo fixo (IATF) associada à detecção de estro por marcação da cauda e presença de muco vaginal no dia da inseminação em vacas Nelore / Efficiency of artificial inseminatio n in fixed time (FTAI) associated with estrus detection by marking the tail and the presence ofvaginal mucus on the day of insemination in Nelore cows

The objective of this study was to evaluate the efficiency of artificial insemination in fixed timeassociated with estrus detection in Nellore cows. They used 917 females, all submitted to estrus synchronizationprotocol and formed two groups: G1 (n = 489), marked on the back with fluorescent dye and then checked if thecroup was blurred or not, and had vaginal mucus or not and G2 (n = 428) were formed by females inseminatedonly synchronized. Pregnancy diagnosis was performed by ultrasound 30 days after insemination. In G1 and G2,pregnancy rates were, respectively, 46.01% and 41.12%. In G1, blurred females (52.19%), not blurred(21.78%), presence of mucus (62.57%) and no mucus (35.97%). Pregnancy rates did not differ between thegroups G1 and G2. In G1, blurred females or mucus had higher rates. It is concluded that the detection ofestrus, insemination favored the pregnancy rate.

Expression of proliferating cell nuclear antigen in the endometrium of mares during estrus and at early diestrus / Expressão do antígeno núcleo celular proliferante no endométrio de éguas durante o estro e início do diestro

Immunohistochemical expression of proliferating cell nuclear antigen (PCNA) was evaluated in the endometrium of mares during estrus and at early diestrus. Three samples were collected by endometrial biopsy from 10 mares, on estrus/ second day, in the ovulation day and seven days after the ovulation day. PCNA expression was high in luminal epithelium and low in endometrial glands on samples taken on estrus/second day and on the ovulation day (p 0.05). For samples collected on the seventh day following ovulation, the averaged PCNA immunostaining was higher in glandular epithelium (p 0.05). The study revealed that luminal epithelial cells exhibit higher proliferation during estrus and glandular epithelial cells exhibited higher proliferation during diestrus(AU)

A expressão do antígeno núcleo celular proliferante (ANCP) foi avaliada no endométrio de éguas durante o estro e início do diestro. Em cada uma de dez éguas foram efetuadas biópsias do endométrio em três momentos dos respectivos ciclos reprodutivos: segundo dia do estro, dia da ovulação e sete dias após a ovulação. Nas amostras colhidas no segundo dia do estro e no dia da ovulação, a expressão do ANCP foi elevada no epitélio luminal e baixa nas glândulas endometriais (p 0,05). Nas amostras colhidas no sétimo dia após a ovulação, a média de ANCP imunologicamente corado foi maior no epitélio glandular (p 0,05). O estudo revelou que as células do epitélio luminal apresentaram a maior proliferação durante o estro e que as células epiteliais glandulares apresentaram a maior proliferação durante o diestro(AU)