Atualizações no controle do ciclo estral em ovinos / Updates on the control of the estrous cycle in sheep

Nos últimos anos, observou-se um aumento no tamanho do rebanho ovino no país, indicando uma retomada na ovinocultura. Para melhorar a eficiência reprodutiva desses animais, a utilização de biotécnicas tem se mostrado uma ferramenta importante. Dentre essas biotécnicas, destacam-se os protocolos de sincronização do ciclo estral, os quais frequentemente utilizam progesterona associada a gonadotrofinas ou análogos da prostaglandina em duas aplicações. Este artigo tem como objetivo revisar os protocolos de sincronização utilizados em ovinos e apresentar atualizações relevantes sobre os mesmos.(AU)

In recent years, there has been an increase in the size of the sheep herd in the country, indicating a recovery in sheep farming. To improve the reproductive efficiency of these animals, the use of biotechniques has been shown to be an important tool. Among these biotechniques, estrous cycle synchronization protocols stand out, which frequently use progesterone associated with gonadotropins or prostaglandin analogues in two applications. This article aims to review the synchronization protocols used in sheep and present relevant updates about them.(AU)

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)

Effect of 20 mg fluorogestone acetate (FGA) sponges on reproductive parameters of dairy ovine breeds in Southern Italy

Background: Intravaginal devices containing progestins are widely used for oestrus synchronization in sheep. Progestins give economic benefits to farmers but may have some limitations and the efficacy strictly depends on farm management. There are different devices, with different molecules (progesterone, medroxyprogesterone acetate, fluorogestone acetate), different dosages and long (12-14 days) and short-term (5-7 days) protocols. Experimental studies often include a limited number of animals and are held at different latitudes and with different system of management. To our knowledge, there are few reports in the literature on field application of the recently licensed 20 mg fluorogestone acetate (FGA) sponges in large ewe flocks, excluding the registration trials. Materials, Methods & Results: This study was designed to evaluate oestrous synchronization in 2 different breeds. A total of 1100 Lacaune (L) and 618 Sarda (S) were assigned to 8 groups, comparing multiparous (M) and nulliparous (N) and those synchronized in November (n) and May (m). The groups were: LMm (n. 556), LNm (n. 180), SMm (n. 70), SNm (n. 32), LMn (n. 242), LNn (n. 222), SMn (n. 440) e SNn (n. 76). The intravaginal sponge was inserted for 14 days. At sponge withdrawal, eCG (400 IU, IM) was injected, and rams were joined into flocks 30 h later with a male/female ratio of 1:8. Transrectal ultrasonography was performed for pregnancy diagnosis after 30 days. Fertility parameters such as oestrus (OR), pregnancy (PR), lambing rates (LR) and prolificacy were calculated. Fisher exact test was used to compare parameters of each group with the corresponding and significance was set at P < 0.01. The use of intravaginal sponges in this study was easily performed in all animals. In nulliparous groups, digital insertion of the sponge, instead of the applicator, was preferred to avoid discomfort. Sponge loss was observed in 2% of treated ewes. At the removal of the sponge, mild vaginal contamination was observed in 90% of the ewes. Ultrasound finding of embryo resorption, pseudopregnancy and pyometra were found in rates under 2%. The loss of pregnancy ranged from 0 to 3.6% without significant differences among groups. The SMn group showed the best performances (0.91 OR, 0.88 PR, 0.85 LR), significantly higher than the other groups. Prolificacy was maximum in the LMn (1.68) and minimum in the SNm group (1.06), without significant differences among groups. Discussion: The 14-day regimen based on 20 mg FGA-releasing intravaginal devices is an easy and satisfactory synchronization regimen to improve the productivity and the fertility of sheep farm, and this can be managed and optimized in different breeding conditions. In this study, Sarda breed shows a good adaption to the environment with adult ewes giving the best results in reproductive season. However young Sarda ewes were less productive especially in non-breading season. Lacaune showed good reproductive potential, young and adult ewes responded to progestins in reproductive and non-reproductive season. It was confirmed that the reproductive performance is affected by season, age, and breed. This study encourages the breeding of indigenous breeds by implementing the management with modern technologies. The imported highly productive breeds, if well managed, can give a production less influenced by seasonal variables and age.

Modulation of sexual behavior of Morada Nova ewe by the season of the year in a semiarid equatorial environment

The objective was to evaluate the effect of the season on the sexual behavior patterns adopted by Morada Nova sheep in the Brazilian semiarid region. A total of 55 and 59 female sheep were used in the rainy and dry seasons, respectively, attended by four males of the same breed in rotation. The females identified in oestrus were released in a pasture, together with the breeder of the day for each season, and aspects of sexual behavior were measured for an uninterrupted period of 11 hours/day. Assuming a negative binomial distribution, the behavioral frequencies were subjected to deviation analysis and compared using the chi-square. Heading in the male was observed more frequently during the rainy season (0.12) and shifts with higher temperatures; the turn of the head in relation to the man was observed more frequently during the dry season (2.49). The interactions between seasons and shifts significantly affected the following behaviors: sniffing the male, sniffing the male's urogenital region, wagging the tail, lifting the tail, and urinating. Behavioral variables were influenced by the season. Morada Nova sheep reduce their water intake and grazing time to engage more efficiently in reproductive activities, thus demonstrating an ability to adapt to the Caatinga.

Modulation of sexual behavior of Morada Nova ewe by the season of the year in a semiarid equatorial environment

he objective was to evaluate the effect of the season on the sexual behavior patterns adopted by Morada Nova sheep in the Brazilian semiarid region. A total of 55 and 59 female sheep were used in the rainy and dry seasons, respectively, attended by four males of the same breed in rotation. The females identified in oestrus were released in a pasture, together with the breeder of the day for each season, and aspects of sexual behavior were measured for an uninterrupted period of 11 hours/day. Assuming a negative binomial distribution, the behavioral frequencies were subjected to deviation analysis and compared using the chi-square. Heading in the male was observed more frequently during the rainy season (0.12) and shifts with higher temperatures; the turn of the head in relation to the man was observed more frequently during the dry season (2.49). The interactions between seasons and shifts significantly affected the following behaviors: sniffing the male, sniffing the male's urogenital region, wagging the tail, lifting the tail, and urinating. Behavioral variables were influenced by the season. Morada Nova sheep reduce their water intake and grazing time to engage more efficiently in reproductive activities, thus demonstrating an ability to adapt to the Caatinga.(AU)

Effect of different protocols for estrus synchronization on reproductive performance of Santa Inês ewes under Amazon environmental conditions

The objective of this study was to evaluate the effect of different hormonal protocols on the reproductive performance of Santa Inês ewes in Amazon environmental conditions. Twenty-two Santa Inês ewes between 3 and 4 years-old were distributed in a randomized block experimental design, where the treatments consisted of two protocols for estrus synchronization (short and long) with eleven animals each. Data on the occurrence of estrus were described for each protocol. Data of estrus, pregnancy, and prolificity were firstly subjected to ANOVA and a subsequent Tukeys test. Results were considered significant at p 0.05. The short-term protocol presented an interesting successful rate, where above 70% ewes tested had estrus. The long-term protocol also achieved a high successful rate, where above 80% ewes tested had estrus. However, comparing the protocols, the long-term protocol presented better results of positive estrus and pregnancy rates in ewes. Thus, it can be concluded that both protocols presented satisfactory results regarding estrus manifestation, and prolificity (lambs produced per ewe). However, under Amazon environmental conditions, the long-term protocol presented better results regarding positive manifestation of estrus and pregnancy rate.(AU)

Effect of different protocols for estrus synchronization on reproductive performance of Santa Inês ewes under Amazon environmental conditions

The objective of this study was to evaluate the effect of different hormonal protocols on the reproductive performance of Santa Inês ewes in Amazon environmental conditions. Twenty-two Santa Inês ewes between 3 and 4 years-old were distributed in a randomized block experimental design, where the treatments consisted of two protocols for estrus synchronization (short and long) with eleven animals each. Data on the occurrence of estrus were described for each protocol. Data of estrus, pregnancy, and prolificity were firstly subjected to ANOVA and a subsequent Tukeys test. Results were considered significant at p 0.05. The short-term protocol presented an interesting successful rate, where above 70% ewes tested had estrus. The long-term protocol also achieved a high successful rate, where above 80% ewes tested had estrus. However, comparing the protocols, the long-term protocol presented better results of positive estrus and pregnancy rates in ewes. Thus, it can be concluded that both protocols presented satisfactory results regarding estrus manifestation, and prolificity (lambs produced per ewe). However, under Amazon environmental conditions, the long-term protocol presented better results regarding positive manifestation of estrus and pregnancy rate.

Estrous synchronization in sheep with reused progesterone devices and eCG

The objective of the present research was to determine the effect of long synchronization protocols based on reused progesterone devices (controlled internal drug release [CIDR]) associated with different doses of equine chorionic gonadotropin (eCG) on reproductive variables in crossbred sheep (Suffolk × Kathadin × Dorset). The CIDR were used for eleven days in a previous study in sheep from the same herd and were washed and disinfected before reusing. Sixty-four sheep, in the reproductive season, were randomly assigned to four experimental groups (n = 16). Treatments consisted of a group with 10 d CIDR and 300 IU eCG; a group with 10 d CIDR and 400 IU of eCG; a group with 12 d CIDR and 300 IU of eCG; and a group with 12 d CIDR and 400 IU of eCG. A completely randomized design was used. There was an estrous presentation rate of 100% in all treatments. The begining of estrous, gestation rate, fertility rate, type of parturition, and prolificacy index were equal between groups. Progesterone serum concentration was higher in sheep from the 10 d CIDR groups. The CIDR, reused for the second time, associated with 300 or 400 IU of eCG for estrous synchronization in sheep, are effective to obtain good pregnancy rates and ensures higher prolificacy rates.

Técnica de inseminação artificial por tração cervical e função luteal em ovelhas Santa Inês após estro sincronizado com cloprostenol ou progestágeno-eCG / Technique of artificial ins emination by cervical traction and luteal function in Santa Inês ewes after synchronized estrus with cloprostenol or progestagen-eCG

Avaliou-se a influência do protocolo de sincronização de estro na execução da técnica de inseminação artificial por tração cervical (ITC) e subsequente perfil sérico de progesterona em ovelhas Santa Inês. Um grupo foi submetido a duas aplicações de cloprostenol com sete dias de intervalo (PGF2α, n=43), outro grupo foi sincronizado com MAP-eCG (P4-eCG, n=40) e ovelhas ao estro natural (EN, n=10) formaram grupo controle. Com as ovelhas contidas em estação, foi realizada a técnica ITC utilizando um aplicador metálico e mandril. Foram avaliadas a profundidade de penetração e intensidade de reação da ovelha ao manejo da técnica. Dosagens de estradiol e progesterona foram feitas antes e depois da ITC/estro natural, respectivamente. Os níveis de estradiol foram superiores com P4-eCG vs PGF2α (P < 0,05), mas não houve influência do protocolo na execução da técnica. Ocorreram 83,5% de deposição intrauterina do sêmen, o tempo médio foi de 32 segundos e 90,7% das ovelhas apresentaram reação fraca ou moderada durante o manejo. Os níveis de progesterona foram semelhantes entre ITC e estro natural. Independente do protocolo hormonal, a técnica ITC em ovelhas Santa Inês mantidas em estação mostrou-se viável no tempo de penetração da cérvice e deposição intrauterina do sêmen, não comprometendo a função luteal subsequente.(AU)

The influence of estrus synchronization protocol was evaluated on the artificial insemination technique by cervical traction (ICT) and subsequent progesterone serum profile in Santa Inês ewes. One group was submitted to two applications of cloprostenol seven days apart (PGF2α, n=43), another group was synchronized with MAP-eCG (P4-eCG, n=40) and ewes at natural estrus (NE, n=10) formed a control group. With the ewe contained in the stand position, the ICT technique was performed using a metal applicator and mandrel. Depth of penetration and reaction intensity of the ewe to the handling of the technique were evaluated. Dosages of estradiol and progesterone were performed before and after ICT / natural estrus, respectively. Estradiol levels were higher with P4-eCG vs PGF2α(AU)

Técnica de inseminação artificial por tração cervical e função luteal em ovelhas Santa Inês após estro sincronizado com cloprostenol ou progestágeno-eCG / Technique of artificial ins emination by cervical traction and luteal function in Santa Inês ewes after synchronized estrus with cloprostenol or progestagen-eCG

Avaliou-se a influência do protocolo de sincronização de estro na execução da técnica de inseminação artificial por tração cervical (ITC) e subsequente perfil sérico de progesterona em ovelhas Santa Inês. Um grupo foi submetido a duas aplicações de cloprostenol com sete dias de intervalo (PGF2α, n=43), outro grupo foi sincronizado com MAP-eCG (P4-eCG, n=40) e ovelhas ao estro natural (EN, n=10) formaram grupo controle. Com as ovelhas contidas em estação, foi realizada a técnica ITC utilizando um aplicador metálico e mandril. Foram avaliadas a profundidade de penetração e intensidade de reação da ovelha ao manejo da técnica. Dosagens de estradiol e progesterona foram feitas antes e depois da ITC/estro natural, respectivamente. Os níveis de estradiol foram superiores com P4-eCG vs PGF2α (P < 0,05), mas não houve influência do protocolo na execução da técnica. Ocorreram 83,5% de deposição intrauterina do sêmen, o tempo médio foi de 32 segundos e 90,7% das ovelhas apresentaram reação fraca ou moderada durante o manejo. Os níveis de progesterona foram semelhantes entre ITC e estro natural. Independente do protocolo hormonal, a técnica ITC em ovelhas Santa Inês mantidas em estação mostrou-se viável no tempo de penetração da cérvice e deposição intrauterina do sêmen, não comprometendo a função luteal subsequente.

The influence of estrus synchronization protocol was evaluated on the artificial insemination technique by cervical traction (ICT) and subsequent progesterone serum profile in Santa Inês ewes. One group was submitted to two applications of cloprostenol seven days apart (PGF2α, n=43), another group was synchronized with MAP-eCG (P4-eCG, n=40) and ewes at natural estrus (NE, n=10) formed a control group. With the ewe contained in the stand position, the ICT technique was performed using a metal applicator and mandrel. Depth of penetration and reaction intensity of the ewe to the handling of the technique were evaluated. Dosages of estradiol and progesterone were performed before and after ICT / natural estrus, respectively. Estradiol levels were higher with P4-eCG vs PGF2α

Comparative analysis of the hormone production and gene expression profiles in ovine uterus tissue during oestrus cycle synchronized using medroxyprogesterone acetate plus eCG and prostaglandin analogue / Análise comparativa da produção de hormônios e perfis de expressão gênica em tecido uterino ovino durante o ciclo estral sincronizado usando acetato de medroxiprogesterona mais eCG e análogo de prostaglandina

The combination of medroxyprogesterone acetate (MPA) and gonadotropin chorionic (eCG) has been widely used to synchronize oestrus cycle in sheep, but their effects on the gene expression in uterine tissue are yet to be elucidated. To evaluate the effect of MPA + eCG or prostaglandin analogue (PA) treatments on the rate of oestrus cycle synchronization, as well as further hormone production and gene expression profiles in uterine tissue, 14 Santa Inês ewes were randomly selected. The MPA + eCG group (n=7) received intravaginal insertion of MPA-impregnated sponges for 14 days and was administered 350 IU eCG on the day of sponge withdrawal. The PA group (n=7) was administered two doses of 100 µg of PA separated by 12 days. The ewes were assessed for the rate of oestrus cycle synchronization and the serum concentrations of progesterone (P4) and estradiol (E2). Additionally, the expression of estrogen receptor (ERα), progesterone receptor (P4R), and immunolocalization of interferon receptor (IFNAR1) in the uterine tissue samples collected 15th day post-mating were examined. The rate of oestrus cycle synchronization was 100% (n=7/7) and 57.14% (n=4/7) in the MPA + eCG and PA groups, respectively. Moreover, the MPA + eCG group exhibited higher serum concentration of P4 than the PA group (p < 0.05). However, the E2 serum concentration did not differ between the two groups (p > 0.05). The relative expression of P4R and ERα mRNA analyzed using real-time PCR and immunodetection of IFNAR1 were similar between the two groups tested (p > 0.05). Conclusively, MPA + eCG treatment improved the rate of oestrus cycle synchronization and endogenous P4 production; however, it did not affect the expression of sex steroid receptors and IFNAR1 in uterine ovine tissue.(AU)

A combinação de acetato de medroxiprogesterona (MPA) com gonadotrofina coriônica (eCG) é amplamente utilizada para sincronizar o estro de ovelhas, mas seus possíveis efeitos sobre a expressão gênica em tecido uterino não foram elucidados. Para avaliar o efeito dos protocolos MPA + eCG ou análogo de prostaglandina (PA) sobre a taxa de sincronização do estro, bem como na futura produção hormonal e expressão gênica em tecido uterino, 14 ovelhas Santa Inês foram selecionadas. O grupo MPA + eCG (n=7) recebeu a inserção de esponjas impregnadas de MPA por via intravaginal por 14 dias e 350 UI de eCG no dia da retirada da esponja. O grupo PA recebeu duas doses de 100 µg de PA administradas com 12 dias de intervalo. As ovelhas foram avaliadas quanto à taxa de sincronização do estro, concentração sérica de progesterona (P4) e estradiol (E2). Além disso, foram examinadas a expressão do receptor de estradiol (ERα), receptor de progesterona (P4R) e localização do receptor de interferon (IFNAR1), a partir de amostras de tecido uterino coletadas 15 dias após o acasalamento. A taxa de sincronização do estro foi 100% (n = 7/7) e 57,14% (n = 4/7) nos grupos MPA + eCG e PA, respectivamente. Além disso, o grupo MPA + eCG apresentou maior concentração sérica de P4 em comparação com o grupo PA (P < 0,05). No entanto, a concentração sérica de E2 não diferiu entre os grupos testados (P > 0,05). A expressão relativa de RNAm para P4R e ERα analisado por PCR em tempo real e imunodetecção de IFNAR1 foi semelhante entre os grupos testados (P > 0,05). Em conclusão, o tratamento com MPA + eCG melhora a taxa de sincronização do estro e a produção de progesterona endógena; contudo, não afeta a regulação da expressão de receptores de esteroides sexuais e IFNAR1 no tecido uterino de ovinos.(AU)

Prevalência de Oestrus ovis (Diptera: Oestridae) em ovinos de Ituiutaba, região sudeste do Brasil / Prevalence of Oestrus ovis (Diptera: Oestridae) in sheep from Ituiutaba, southeast region of Brazil

Dentre as doenças que podem atingir as cavidades nasais dos pequenos ruminantes, destaca-se a oestrose. No Brasil, mais especificamente na região Sudeste, os relatos estão limitados ao estado de São Paulo e ao município de Araxá, Minas Gerais. Assim, procurou-se avaliar a prevalência parasitária do Oestrus ovis em ovinos criados no município de Ituiutaba, Minas Gerais-Brasil, correlacionando ao mesmo tempo o tamanho e estágio larval com a sua localização anatômica. Oitenta e oito hemicabeças de Ovis aries mestiços Santa Inês com Dorper saudáveis foram utilizadas aleatoriamente. As larvas visualizadas foram então coletadas e fixadas para serem quantificadas e analisadas em relação ao seu tamanho e estágio de desenvolvimento. Conclui-se que a oestrose é um problema existente no município de Ituiutaba, sendo este o primeiro estudo completo sobre a prevalência deste parasito no estado de Minas Gerais. Por distribuição anatômica, apenas as diferenças das médias larvais totais entre o seio frontal e o meato nasal ventral, meato nasal comum e a nasofaringe foram significativas - o que confirma a preferência das larvas por essa região. Em tamanho, a diferença significativa só ocorreu mediante a comparação entre o tamanho e estágio das larvas, informação crucial para uma melhor compreensão da progressão cíclica, sintomatologia clínica e profilaxia dos animais.

Among the diseases which can afflict the nasal cavities of small ruminants, oestrosis stands out. In Brazil, more specifically in its South-East region, the reports are limited only to the State of São Paulo and to the municipality of Araxá, Minas Gerais. Therefore, it has been sought to assess the parasitic prevalence of Oestrus ovis in sheep farmed in the municipality of Ituiutaba, Minas Gerais-Brazil, while correlating the larval size and stage, and its anatomical localization. Eighty-eight hemiheads of healthy Santa Inês/Dorper crossbreds Ovis aries have been used at random. The larvae in view were then collected and fixated to be quantified and analyzed in regard of size and stage of development. It is concluded that the oestrosis is an existing problem in the municipality of Ituiutaba, this being the first complete study on the prevalence of this parasite in the State of Minas Gerais. By anatomical distribution, only the differences of total larval averages between the frontal sinus and the ventral nasal meatus, the common nasal meatus and the nasopharynx have been significant. In size, the significant difference has been there only upon comparison between the size and the larval stage, information that is crucial for a better understanding of the cyclic progression, of the clinical symptomatology, and animal prophylaxis.

Antioxidant capacity, reproductive response and glucose concentration and insulin of ewes supplemented prior to insemination with orange residue / [Capacidade antioxidante, resposta reprodutiva e concentração de glicose e insulina de ovelhas suplementadas antes da inseminação com resíduo de laranja]

The objective was to evaluate the antioxidant capacity, glucose and insulin concentration and reproductive performance of ewes supplemented with orange residue prior to insemination. Fifty-five multiparous ewes were divided into two corrals, and 15 unbred ewes were kept individually to measure feed consumption. Two integral diets were administered; T0: control treatment and T1: with 20% of dry matter of orange residue. Ten days after the start of supplementation, the ewes were synchronized. Supplementation was finalized prior to artificial insemination, then, a blood sample was taken to measure the antioxidant capacity and glucose and insulin concentration. An analysis of variance was made to evaluate the effect of treatment on the antioxidant capacity, glucose and insulin; and to analyze the response to estrus, percentage of gestation and prolificity a ji squared test was performed. Of 9 antioxidant compounds found in the orange residue, hesperidin (7.44%), chlorogenic acid (0.50%) and protocatechuic acid had the highest concentration. Feed intake, estrus response, percentage of gestation, antioxidant capacity, and glucose and insulin concentration were not affected by the treatment. It is concluded that inclusion of 20% of orange residue in the diet prior to insemination in ewes is possible.(AU)

O objetivo deste estudo foi avaliar a capacidade antioxidante, a concentração de glicose e insulina e o comportamento reprodutivo de ovelhas suplementadas com resíduo de laranja antes da inseminação. Cinquenta e cinco ovelhas multíparas foram divididas em dois currais e 15 ovelhas sem raça foram mantidas individualmente para se medir o consumo de ração. Duas dietas integrais foram administradas; T0: tratamento controle e T1: dieta com 20% de resíduo de laranja seco. Dias após o início da suplementação, as ovelhas foram sincronizadas. A suplementação foi finalizada antes da inseminação artificial e, em seguida, foi coletada uma amostra de sangue para medir a capacidade antioxidante e a concentração de glicose e insulina. Uma análise de variância foi feita para avaliar o efeito do tratamento sobre a capacidade antioxidante, a glicose e a insulina, e um teste do ji quadrado foi realizado para analisar a resposta ao estro, a porcentagem de gestação e de prolificidade. Dos nove compostos antioxidantes encontrados no resíduo laranja, a hesperidina (7,44%), o ácido clorogênico (0,50%) e o ácido protocatecuico foram os de maior concentração. O consumo alimentar, a resposta ao estro, a porcentagem de gestação, a capacidade antioxidante, a concentração de glicose e a insulina não foram afetados pelo tratamento. Conclui-se que é possível a inclusão de 20% de resíduos de laranja na dieta antes da inseminação em ovelhas.(AU)

Synchronization of follicular wave emergence does not improve embryonic yield in superovulated ewes

The present study aimed to investigate the effects of a combination of progesterone with different doses of E-17β on following end points: (1) ovarian follicular dynamics and emergence of a new follicular wave, and (2) superovulatory response and embryo yield. In Experiment 1, 28 ewes were randomly divided into four groups (n = 7) to receive either 2.0 mg, 1.0 mg, 0.5 mg or none E-17β one day after insertion of a progesterone device. The different doses of estradiol similarly delayed the moment of follicular emergence (overall mean = 3.1 ± 1.0 days vs. control group = 0.86 ± 1.0 days; P < 0.01), but the emergence of the new wave showed greater synchronization with the 0.5 mg dosage of E-17β. In Experiment 2, sixty-two donor ewes received an internal progesterone release device (day -1) for 7 d and 1 d after the insertion of this device (day 0) were allocated randomly to receive 0.5 mg of E-17β or only the vehicle (control group). Superstimulation was initiated on day 3 with the administration of 133 mg of pFSH in eight decreasing doses. Contrary to expectations, the protocol with the administration of 0.5 mg E-17β did not improve the percentage of donors with > 2 CL, the number of CL and the production of embryos (P > 0.05). It was concluded that the combination of progesterone and 0.5 mg E-17β was more efficient in synchronizing the emergence of the new follicular wave, however this approach seems to be unnecessary in ewes superovulation programs.(AU)

Prevalence of Oestrus ovis (Diptera: Oestridae) in sheep from Ituiutaba, south-east region of Brazil / Prevalência de Oestrus ovis (Diptera: Oestridae) em ovinos de Ituiutaba, região sudeste do Brasil

Among the diseases which can afflict the nasal cavities of small ruminants, oestrosis stands out. In Brazil, more specifically in its South-East region, the reports are limited only to the State of São Paulo and to the municipality of Araxá, Minas Gerais. Therefore, it has been sought to assess the parasitic prevalence of Oestrus ovis in sheep farmed in the municipality of Ituiutaba, Minas Gerais-Brazil, while correlating the larval size and stage, and its anatomical localization. Eighty-eight hemiheads of healthy Santa Inês/Dorper crossbreds Ovis aries have been used at random. The larvae in view were then collected and fixated to be quantified and analyzed in regard of size and stage of development. It is concluded that the oestrosis is an existing problem in the municipality of Ituiutaba, this being the first complete study on the prevalence of this parasite in the State of Minas Gerais. By anatomical distribution, only the differences of total larval averages between the frontal sinus and the ventral nasal meatus, the common nasal meatus and the nasopharynx have been significant. In size, the significant difference has been there only upon comparison between the size and the larval stage, information that is crucial for a better understanding of the cyclic progression, of the clinical symptomatology, and animal prophylaxis.

Dentre as doenças que podem atingir as cavidades nasais dos pequenos ruminantes, destaca-se a oestrose. No Brasil, mais especificamente na região Sudeste, os relatos estão limitados ao estado de São Paulo e ao município de Araxá, Minas Gerais. Assim, procurou-se avaliar a prevalência parasitária do Oestrus ovis em ovinos criados no município de Ituiutaba, Minas Gerais-Brasil, correlacionando ao mesmo tempo o tamanho e estágio larval com a sua localização anatômica. Oitenta e oito hemicabeças de Ovis aries mestiços Santa Inês com Dorper saudáveis foram utilizadas aleatoriamente. As larvas visualizadas foram então coletadas e fixadas para serem quantificadas e analisadas em relação ao seu tamanho e estágio de desenvolvimento. Conclui-se que a oestrose é um problema existente no município de Ituiutaba, sendo este o primeiro estudo completo sobre a prevalência deste parasito no estado de Minas Gerais. Por distribuição anatômica, apenas as diferenças das médias larvais totais entre o seio frontal e o meato nasal ventral, meato nasal comum e a nasofaringe foram significativas - o que confirma a preferência das larvas por essa região. Em tamanho, a diferença significativa só ocorreu mediante a comparação entre o tamanho e estágio das larvas, informação crucial para uma melhor compreensão da progressão cíclica, sintomatologia clínica e profilaxia dos animais.

Application of hormonal subdoses at the Bai Hui acupoint for estrus synchronization in sheep / Aplicação de subdoses hormonais no ponto de acupuntura Bai Hui para sincronização de estro em ovelhas

Here, the efficiency of applying subdoses of equine chorionic gonadotropin (eCG) and prostaglandin F2α (PGF2α) at the Bai Hui (BH) acupoint for estrus synchronization in sheep was evaluated. Thirty Santa Inês ewes received intravaginal sponges containing 60 mg medroxyprogesterone acetate for 7 days. The animals were divided into five treatments (T) (n=6): T1 (control), 132.5 µg PGF2α (100% of dose) and 300 IU eCG (100% of dose), both intramuscularly (IM); T2, 39.75 µg PGF2α (30% of dose) at the BH acupoint and 300 IU eCG (100% of dose) IM; T3, 132.5 µg PGF2α (100% of dose) IM and 90 IU eCG (30% of dose) at the BH acupoint; T4, 39.75 µg PGF2α (30% of dose) and 90 IU eCG (30% of dose), both at the BH acupoint; and T5, 39.75 µg PGF2α (30% of dose) and 90 IU eCG (30% of dose) both at a false acupoint (IM, at the same location as in T1). After 12 h of sponge removal and hormone application, the ewes were subjected to monitoring for estrus and mating and ultrasound assessments of follicular growth and ovulation time every 12 h. The data were evaluated for normality and subjected to analysis of variance, considering a 5% probability. There were no differences in the percentage of animals in estrus (93.3±9.1%), interval from sponge removal to estrus onset (48.1±6.0 h), interval from sponge removal to estrus end (69.6±5.4 h), duration of estrus (24.0±4.7 h), interval from sponge removal to ovulation (73.7±5.9 h), interval from estrus onset to ovulation (26.5±2.3 h), size of the largest follicle (6.7±0.4 mm), follicular growth rate (0.8±0.1 mm•day-1), number of ovulations (1.3±0.1), and plasma progesterone levels 7 days after ovulation (9.6±2.0 ng•mL-1). The cost of the synchronization protocol per animal was US$ 4.37, 4.12, 2.96, 2.71, and 2.71 for T1, T2, T3, T4, and T5, respectively, with 37.99% cost reduction using PGF2α and eCG at 30% of the conventional doses. Therefore, the application of reduced PGF2α (39.75 µg) and eCG (90 IU) doses at the BH or false acupoint effectively synchronized estrus and reduced protocol cost in sheep, indicating that the conventional doses are overestimated.(AU)

Aqui, foi avaliada a eficiência da aplicação de subdoses de gonadotrofina coriônica equina (eCG) e prostaglandina F2α (PGF2α) no ponto de acupuntura Bai Hui (BH) para sincronização de estro em ovelhas. Trinta ovelhas Santa Inês receberam esponjas intravaginais contendo 60 mg de acetato de medroxiprogesterona por 7 dias. Os animais foram divididos em cinco tratamentos (T) (n=6): T1 (controle), 132,5 µg PGF2α (100% da dose) e 300 UI de eCG (100% da dose), ambos por via intramuscular (IM); T2, 39,75 µg de PGF2α (30% da dose) no ponto de acupuntura BH e 300 UI eCG (100% da dose) IM; T3, 132,5 µg PGF2α (100% da dose) IM e 90 UI eCG (30% da dose) no ponto de acupuntura BH; T4, 39,75 µg PGF2α (30% da dose) e 90 UI eCG (30% da dose), ambos no ponto de acupuntura BH; e T5, 39,75 µg PGF2α (30% da dose) e 90 UI eCG (30% da dose) ambos em um falso acuponto (IM, no mesmo local que em T1). Após 12 horas da retirada da esponja e aplicação do hormônio, as ovelhas foram submetidas ao monitoramento do estro e acasalamento, e avaliação ultrassonográfica do crescimento folicular e tempo de ovulação a cada 12 horas. Os dados foram avaliados quanto à normalidade e submetidos à análise de variância, considerando 5% de probabilidade. Não houve diferenças na porcentagem de animais em estro (93,3 ± 9,1%), intervalo da remoção da esponja ao início do estro (48,1 ± 6,0 h), intervalo da remoção da esponja ao final do estro (69,6 ± 5,4 h), duração do estro (24,0 ± 4,7 h), intervalo da remoção da esponja à ovulação (73,7 ± 5,9 h), intervalo do início do estro à ovulação (26,5 ± 2,3 h), tamanho do maior folículo (6,7 ± 0,4 mm), taxa de crescimento folicular (0,8 ± 0,1 mm•dia-1), número de ovulações (1,3 ± 0,1) e níveis de progesterona plasmática 7 dias após a ovulação (9,6 ± 2,0 ng•mL-1). O custo do protocolo de sincronização por animal foi de US $ 4,37, 4,12, 2,96, 2,71 e 2,71 para T1, T2, T3, T4 e T5, respectivamente, com redução de custo de 37,99% usando PGF2α e eCG a 30% das doses convencionais. Portanto, a aplicação de PGF2α (39,75 µg) e doses reduzidas de eCG (90 UI) no BH ou falso acuponto sincronizaram efetivamente o estro e reduziram o custo do protocolo em ovelhas, indicando que as doses convencionais estão superestimadas.(AU)

Multiple matings modify the estrous length, the moment of ovulation, and the estradiol and LH patterns in ewes

In several species, mating reduces the estrous length and advances ovulation. The aim of this study was to determine if multiple matings reduces the estrous length and modifies the moment of ovulation, as well as the estradiol and LH patterns in ewes. The estrous cycle of Corriedale ewes was synchronized, and the onset of receptivity was monitored every 3 h with rams, avoiding mating. At the estrous onset, ewes were assigned to two experimental groups (n=10 each): 1) estrous was monitored every 3 h with a ram avoiding mating (group CON), and 2) a ram was allowed to mate and ejaculate once every 3 h (group MAT). The ovaries were scanned with transrectal ultrasonography and blood samples were collected for measuring 17β-estradiol and LH concentrations every 3 h until ovulation. Estrus was shorter in MAT than CON ewes (24.7 ± 1.5 h vs. 30.4 ± 1.5 h, respectively; P=0.02); the proportion of animals that ovulated before the end of estrus was greater in CON ewes: (9/10 vs. 3/10, P=0.009). The area under the LH curve (AUC) was greater in MAT than CON ewes (36.1 ± 3.5 ng.h-1.mL-1 vs 24.9 ± 3.5 ng.h-1.mL-1 P=0.03). However, MAT ewes had a lower 17β-estradiol AUC than CON ewes (41.0 ± 4.9 pg.h-1.mL-1 vs 59.4 ± 4.9 pg.h-1.mL-1 P=0.01). Mating reduced the estrous length, induced a greater secretion of LH but less total 17β-estradiol secreted and, additionally, ovulation occurred more frequently after the end of estrus in mated ewes.(AU)

Saliva crystallization in sheep subjected to estrus induction and synchronization protocols

Background: The crystallization of bodily fluids, primarily saliva, has been the subject of study in many species and is asimple alternative to detect estrus because it demands neither a significant financial investment nor qualified professionalsto execute the examination. Fern pattern crystallization has been described in the cervical and nasal mucus, saliva andtear secretion, and in colostrum. Changes in salivary crystallization during the reproduction cycle are related to differenthormonal concentrations in this period. Thus, the present study has evaluated the patterns of saliva crystallization in sheepsubjected to estrus induction and synchronization protocols.Materials, Methods & Results: The sample consisted of 11 crossbreed Corriedale sheep, which were evaluated during twoexperimental periods (spring and autumn), and that underwent induction and synchronizing estrus protocols. In a randomphase of the estrus cycle (day 0), each sheep was implanted with an intravaginal device (Primer®), impregnated with 0.36g of progesterone for seven days. This device was inserted according to manufacturer’s instructions of the manufacturerand with the assistance of a specific applicator. On the day of device removal (day 7), the animals received 0.0375 mg ofD-Cloprostenol (Prolise®) and 10 mg of Folltropin® extracted from the swine pituitary (NIH-FSH-P1 of Folltropin-V) byintramuscular administration. The saliva was collected at six points during the experimental periods: day 1 (3 days beforeplacement of the implant); day 4 (day of insertion of the implant); day 9 (5 days after the insertion of the implant); day11 (day of removal of the implant and application of hormones); day 12 (24 h after removal of the implant [presumableestrus]); and day 13 (48 h after removal of the implant). Smears containing 10 µL of saliva were observed under an opticallight microscope...

Saliva crystallization in sheep subjected to estrus induction and synchronization protocols

Background: The crystallization of bodily fluids, primarily saliva, has been the subject of study in many species and is asimple alternative to detect estrus because it demands neither a significant financial investment nor qualified professionalsto execute the examination. Fern pattern crystallization has been described in the cervical and nasal mucus, saliva andtear secretion, and in colostrum. Changes in salivary crystallization during the reproduction cycle are related to differenthormonal concentrations in this period. Thus, the present study has evaluated the patterns of saliva crystallization in sheepsubjected to estrus induction and synchronization protocols.Materials, Methods & Results: The sample consisted of 11 crossbreed Corriedale sheep, which were evaluated during twoexperimental periods (spring and autumn), and that underwent induction and synchronizing estrus protocols. In a randomphase of the estrus cycle (day 0), each sheep was implanted with an intravaginal device (Primer®), impregnated with 0.36g of progesterone for seven days. This device was inserted according to manufacturers instructions of the manufacturerand with the assistance of a specific applicator. On the day of device removal (day 7), the animals received 0.0375 mg ofD-Cloprostenol (Prolise®) and 10 mg of Folltropin® extracted from the swine pituitary (NIH-FSH-P1 of Folltropin-V) byintramuscular administration. The saliva was collected at six points during the experimental periods: day 1 (3 days beforeplacement of the implant); day 4 (day of insertion of the implant); day 9 (5 days after the insertion of the implant); day11 (day of removal of the implant and application of hormones); day 12 (24 h after removal of the implant [presumableestrus]); and day 13 (48 h after removal of the implant). Smears containing 10 µL of saliva were observed under an opticallight microscope...(AU)

Técnicas reversíveis de rufião em ovinos (Ovis aires) / Reversible techniques of ruffian in sheep (Ovis aires)

Background: The use of teaser rams is an essential practice for detecting estrus in ewes as well as for accelerating puberty and synchronizing ovulation in the animal. There are several methods for preparing teasers, and the method used should be based on an assessment of the producer’s requirements. The ideal technique should be low cost and safe, ensuring the non-fertilization of ewes. This study evaluated the feasibility and effectiveness of two reversible teaser preparation techniques using a reversible plastic clamp. The techniques were compared in terms of functionality, possible post-surgical complications, and hematological changes of the rams as well as durability and reversibility. Materials, Methods & Results: Twelve healthy rams, aged 14-20 months, were divided into two groups (G1 and G2). Blood samples were collected through the jugular vein to perform the following analyses: blood count, total plasma protein, and fibrinogen. Following local infiltrative anesthesia with 5.0 mL 2% lidocaine without vasoconstrictor, the procedure was performed as follows: in G1, the preputial ostium was partially closed, and in G2, sigmoid flexure was performed in the cranial region, approximately 5-8 cm immediately caudal to the scrotal sac. In the postoperative period, 20 mg/kg oxytetracycline and 2.2 mg/kg flunixinmeglumine were intramuscularly administered as a single dose. The wounds were dressed, sprayed with repellent, and allowed to heal for seven days. The procedures in both groups were simple to perform, low cost, and low risk; caused minimal tissue injury; enabled rapid recovery; promoted little or no stress to the animals; are reversible; and left no complications. The animals of both groups satisfactorily identified the females in estrus during the three-month experimental period, maintained libido, and failed to mate with any female. The blood count levels...