Recent advances in treatments for resynchronization of ovulation in small ruminants: a review

Hormonal methodologies to control small ruminants' estrous cycle are worldwide used and evolved, adjusting the application to the precise female physiological moments to enhance reproductive performance. The estrous cycle can be induced and/or synchronized, aiming for fixed-time artificial insemination, or based on estrus behavior signs for insemination, natural or guided mating. Successive protocols can be performed to resynchronize ovulation and increase reproductive outcomes in females that failed to conceive. These recently developed treatments aim to resynchronize the ovulation as earlier as non-pregnancy is detected. The present review aimed to summarize the recent advances and main findings regarding resynchronization protocols used in small ruminants. Lastly, we present future perspectives and new paths to be studied in the subject. The resynchronization treatment is still a growing field in small ruminant reproduction, nevertheless, some enhancements are found in the reproductive outcome, showing that such protocols can be successfully used in sheep and goat production.(AU)

Non jaagsiekte retrovirus associated adenosquamous lung carcinoma in a goat

An 11-year-old pet goat presented a clinical history of acute respiratory distress with ultrasound diagnosis of wide lung injury. The animal was euthanized due to welfare reasons. At necropsy, it was found pleural effusion and adhesion on the right cranioventral thoracic region. The right cranial and middle lung lobes were firm and light gray with a neocavity containing purulent exudate. From the middle lobe, there was a nodular proliferation occupying alveolar spaces, densely cellular and composed by cuboid-columnar epithelial cells arranged in papillae and acini (60%), as well as polygonal cells arranged in nests with squamous differentiation (40%). Marked pleomorphism, anisocytosis and anisocariosis were also noted. A total of 39 mitosis figures for ten fields at 400x magnification were counted. Lung samples were negative for jaagsiekte retrovirus (JSRV) by PCR. Immunostaining for TTF1 and P53 occurred in zones of adenomatous and squamous differentiation, respectively. In MIB-1, 14% (82/594) of immunolabeled cells were observed in the squamous component. In conclusion, the histopathological and immunohistochemical characteristics confirmed the diagnosis of a pulmonary adenosquamous carcinoma, without JSRV involvement, in goat species.(AU)

Is bluetongue virus a risk factor for reproductive failure in tropical hair sheep in Brazil?

Background: Bluetongue is a vector-borne viral disease transmitted by midges from the genus Culicoides. The disease caninfect most of the ruminant and camelid species, but the severe disease is most often seen in european wool and muttonsheep breeds. In this sense, there is a gap in the knowledge on BTV infection in hair sheep breeds from tropical zones.Thus, this study aimed at establishing whether exposure to BTV is a risk factor for reproductive failure in Santa Inês ewes,a hair sheep breed, reared under tropical conditions in Brazil.Materials, Methods & Results: A retrospective cross-sectional study was carried out in sheep farms in São Paulo state,Brazil, after the rainy season. Serum samples from 110 Santa Inês ewes with a history of reproductive disorders, in the last6 months, which were included: abortion, premature birth, stillbirth, retention of placenta, infertility, estrus repetition, fetalmalformation, weak lamb birth and neonatal death were collected. The presence of antibodies against BTV was assessedby agar gel immunodiffusion method (AGID). Serology to the infectious agents Brucela ovis, Lepstopira spp., Toxoplasmagondii, Neospora caninum and Campylobacter sp. were also assessed. Bivariate associations between the outcome andindividual explanatory variables were assessed using the Fisher’s exact test. Abortion was the most common reproductive disorder (53%; 74/139) observed, followed by estrus repetition (12%; 17/139) and infertility (11%; 15/139). Otherdisorders related to the conceptus totaled nearly one fourth of the reported disorders. A total of 20% (22/110) of the eweswere seropositive to BTV. A higher frequency of BTV seropositive than BTV seronegative ewes with a history of abortionwas found. Also, abortion with seroreactivity to BTV was tested for prevalence ratio that showed 1.38 [95% CI 1.10-1.74;P = 0.030]. With regards to the abortion involvement of other infectious diseases associated with the seropositive ewes to...

Is bluetongue virus a risk factor for reproductive failure in tropical hair sheep in Brazil?

Background: Bluetongue is a vector-borne viral disease transmitted by midges from the genus Culicoides. The disease caninfect most of the ruminant and camelid species, but the severe disease is most often seen in european wool and muttonsheep breeds. In this sense, there is a gap in the knowledge on BTV infection in hair sheep breeds from tropical zones.Thus, this study aimed at establishing whether exposure to BTV is a risk factor for reproductive failure in Santa Inês ewes,a hair sheep breed, reared under tropical conditions in Brazil.Materials, Methods & Results: A retrospective cross-sectional study was carried out in sheep farms in São Paulo state,Brazil, after the rainy season. Serum samples from 110 Santa Inês ewes with a history of reproductive disorders, in the last6 months, which were included: abortion, premature birth, stillbirth, retention of placenta, infertility, estrus repetition, fetalmalformation, weak lamb birth and neonatal death were collected. The presence of antibodies against BTV was assessedby agar gel immunodiffusion method (AGID). Serology to the infectious agents Brucela ovis, Lepstopira spp., Toxoplasmagondii, Neospora caninum and Campylobacter sp. were also assessed. Bivariate associations between the outcome andindividual explanatory variables were assessed using the Fishers exact test. Abortion was the most common reproductive disorder (53%; 74/139) observed, followed by estrus repetition (12%; 17/139) and infertility (11%; 15/139). Otherdisorders related to the conceptus totaled nearly one fourth of the reported disorders. A total of 20% (22/110) of the eweswere seropositive to BTV. A higher frequency of BTV seropositive than BTV seronegative ewes with a history of abortionwas found. Also, abortion with seroreactivity to BTV was tested for prevalence ratio that showed 1.38 [95% CI 1.10-1.74;P = 0.030]. With regards to the abortion involvement of other infectious diseases associated with the seropositive ewes to...(AU)

Hormonal protocols for the synchronization and induction of synchronized estrus in dairy ewes kept under tropical conditions

Background: Lacaune is an important sheep breed and shows reproductive seasonality which affects dairy product supply. The most common hormonal protocols are based on progesterone-releasing devices in order to reach reproductive activity. Due to international consumer demand for natural, green, and clean methods, such issues encourage the minimal or absent use of synthetic hormones in livestock. In this sense, the present study tested the efficiency of induction and estrus synchronization protocols in lacaune ewes, considering: application interval of synthetic prostaglandin at the breeding season; length of synthetic progesterone exposure; and eCG dose at the outbreeding season. Materials, Methods & Results: In study 1: 52 ewes were submitted to estrus synchronization protocol using two doses of d-cloprostenol 7 or 9 days apart. In study 2: 47 ewes were submitted to estrus induction protocol using an intravaginal device containing 60 mg of medroxyprogesterone acetate maintained for 6, 9, or 12 days. In study 3: 46 ewes were submitted to synchronized estrus induction protocol using intravaginal progesterone device for six days. On the fifth day, d-cloprostenol and 300 IU or 400 IU of eCG were administered. For all studies, signs of estrus beginning/ending were recorded and natural mating was performed. After 30 days, transrectal ultrasound was performed for pregnancy diagnosis. In study 1, groups presented similar rate of estrus behavior (78.8%) and pregnancy (average 75.6%). Meanwhile, compared to G9days (37.8 ± 7.2 h), interval between the second dose of prostaglandin and beginning of estrus was smaller in G7days (31.5 ± 7.8 h). No difference was found among variables studied in study 2 (P > 0.05), nevertheless the SD for the estrus duration was shorter (P < 0.05) in G6days and G12 days when compared with the G9days . Equally, the SD...

Colheita transcervical de embriões em ovelhas e cabras / Transcervical embryo collection in ewes and does

A biotécnica de múltipla ovulação e transferência de embriões (MOTE) em pequenos ruminantes tem aplicações que se estendem da pesquisa básica à aplicada. Porém, ainda existem etapas no processo da biotécnica que reduzem sua eficiência e restringem sua utilização, a exemplo da necessidade de procedimentos cirúrgicos. Em caprinos, já é possível realizar a MOTE sem nenhuma intervenção cirúrgica e com resultados satisfatórios. Todavia, em ovinos, as particularidades anatômicas da cérvix dificultam sua transposição, fazendo com que etapas cirúrgicas ainda sejam necessárias. Com foco nessa limitação, tem-se estudado e descrito técnicas para a dilatação cervical e métodos para triagem de doadoras de embrião com maior facilidade para transposição cervical. Assim, a colheita não cirúrgica, principalmente na espécie ovina, vem se tornando uma realidade exequível em condições de campo e pesquisa.(AU)

In small ruminants, the multiple ovulation and embryo transfer (MOET) has applications in basic and applied research. However, there are still drawbacks in this biotechnology hampering its applicability and efficiency, as the need of surgical intervention. In goats, it is possible to perform MOET without any surgical procedure and with satisfactory results. Although, in sheep, the anatomical features of the cervix make transcervical transposition challenging, leading to a wider use of surgical steps in this specie. In the attempt to overcome these limitations, techniques for cervical dilation and methods for screening donors with cervices that can be easily transposed have been studied and described. Therefore, the nonsurgical embryo collection, mainly in the ovine species, has become feasible under field and research conditions.(AU)

Colheita transcervical de embriões em ovelhas e cabras / Transcervical embryo collection in ewes and does

A biotécnica de múltipla ovulação e transferência de embriões (MOTE) em pequenos ruminantes tem aplicações que se estendem da pesquisa básica à aplicada. Porém, ainda existem etapas no processo da biotécnica que reduzem sua eficiência e restringem sua utilização, a exemplo da necessidade de procedimentos cirúrgicos. Em caprinos, já é possível realizar a MOTE sem nenhuma intervenção cirúrgica e com resultados satisfatórios. Todavia, em ovinos, as particularidades anatômicas da cérvix dificultam sua transposição, fazendo com que etapas cirúrgicas ainda sejam necessárias. Com foco nessa limitação, tem-se estudado e descrito técnicas para a dilatação cervical e métodos para triagem de doadoras de embrião com maior facilidade para transposição cervical. Assim, a colheita não cirúrgica, principalmente na espécie ovina, vem se tornando uma realidade exequível em condições de campo e pesquisa.

In small ruminants, the multiple ovulation and embryo transfer (MOET) has applications in basic and applied research. However, there are still drawbacks in this biotechnology hampering its applicability and efficiency, as the need of surgical intervention. In goats, it is possible to perform MOET without any surgical procedure and with satisfactory results. Although, in sheep, the anatomical features of the cervix make transcervical transposition challenging, leading to a wider use of surgical steps in this specie. In the attempt to overcome these limitations, techniques for cervical dilation and methods for screening donors with cervices that can be easily transposed have been studied and described. Therefore, the nonsurgical embryo collection, mainly in the ovine species, has become feasible under field and research conditions.

Metastatic seminoma in a male Alpine goat: clinical and histopathological approach

Background: Seminomas are germ cell tumors mainly originating from spermatogonia in the seminiferous tubules andhas been described in several domestic animal species, even though has rarely been described in goats. Moreover, seminomas tumors are not usually metastatic and rarely trigger paraneoplastic syndrome. In this sense, this is a case report ofa 12-year-old male Alpine goat, suspected of testicular neoplasm based on clinical examination and ultrasound imaging,diagnosed as a seminoma with metastasis in liver by histopathology upon necropsy.Case: A 12-year-old male Alpine goat presented a 10 month history of progressive weight loss, prostration, and scrotalsac enlargement. The major clinical findings were pale conjunctival mucus, bilateral nasal catarrhal secretion, obstructivedyspnea, an increased abdominal component, crackling at trachea auscultation, silence upon lung auscultation of the ventralarea and wheezing upon auscultation of the dorsal area, and enlargement of the left testicle with contralateral atrophy. Atthe Ultrasonography scan, the enlarged left testicle presented architecture loss, as well as circumscribed masses differingin echogenicity and echotexture with scattered small hyperechoic nodules. The shrunken right testicle showed acousticshading across the surface suggestive of calcification. Due to the poor prognosis and regard for animal welfare, the goatwas euthanized. The main necropsy findings on testicles were: enlarged left testicle with white parenchyma on the dorsalside as well as diffuse yellow elliptical lesions of 0.5-2.5 cm on the surface in association with two circumscribed areasat the cranial and caudal poles, firm upon cutting. The right testicle was half the typical size, slightly pale, firm at cuttingof the tunica albuginea, and presented dark parenchyma with abundant calcification dots suggestive of microlithiasis.The histological findings included diffuse tumoral stroma of the left testicle...

Metastatic seminoma in a male Alpine goat: clinical and histopathological approach

Background: Seminomas are germ cell tumors mainly originating from spermatogonia in the seminiferous tubules andhas been described in several domestic animal species, even though has rarely been described in goats. Moreover, seminomas tumors are not usually metastatic and rarely trigger paraneoplastic syndrome. In this sense, this is a case report ofa 12-year-old male Alpine goat, suspected of testicular neoplasm based on clinical examination and ultrasound imaging,diagnosed as a seminoma with metastasis in liver by histopathology upon necropsy.Case: A 12-year-old male Alpine goat presented a 10 month history of progressive weight loss, prostration, and scrotalsac enlargement. The major clinical findings were pale conjunctival mucus, bilateral nasal catarrhal secretion, obstructivedyspnea, an increased abdominal component, crackling at trachea auscultation, silence upon lung auscultation of the ventralarea and wheezing upon auscultation of the dorsal area, and enlargement of the left testicle with contralateral atrophy. Atthe Ultrasonography scan, the enlarged left testicle presented architecture loss, as well as circumscribed masses differingin echogenicity and echotexture with scattered small hyperechoic nodules. The shrunken right testicle showed acousticshading across the surface suggestive of calcification. Due to the poor prognosis and regard for animal welfare, the goatwas euthanized. The main necropsy findings on testicles were: enlarged left testicle with white parenchyma on the dorsalside as well as diffuse yellow elliptical lesions of 0.5-2.5 cm on the surface in association with two circumscribed areasat the cranial and caudal poles, firm upon cutting. The right testicle was half the typical size, slightly pale, firm at cuttingof the tunica albuginea, and presented dark parenchyma with abundant calcification dots suggestive of microlithiasis.The histological findings included diffuse tumoral stroma of the left testicle...(AU)

Diagnóstico ultrassonográfico de distúrbios reprodutivos em pequenos ruminantes / Ultrasonographic diagnosis of reproductive disorders in small ruminants

A ultrassonografia (USG) é uma técnica de imagem em tempo real e pouco invasiva. Na produção de ovinos e caprinos, a USG vem sendo utilizada como uma ferramenta auxiliar no manejo reprodutivo, assim como no diagnóstico clínico-reprodutivo de doenças ginecológicas, obstétricas e andrológicas. Por meio da USG é possível a realização de exames em série para monitorar a progressão de uma anormalidade, resposta ao tratamento ou a funcionalidade e morfologia do órgão. Assim, por meio da USG são fornecidas informações substanciais ao profissional do campo e da pesquisa auxiliando na definição de prognósticos, tratamentos, descarte zootécnico e, ainda, na aquisição de reprodutores e matrizes sem distúrbios reprodutivos adquiridos ou congênitos.(AU)

Ultrasonography (USG) is a less invasive, real-time imaging modality. In the sheep and goat farming, USG has been used as an auxiliary tool in the reproductive management, as well as in the clinical-reproductive diagnosis of gynecological, obstetric and andrological disorders. Through the USG, it is possible to perform successive evaluations to monitor the progression of an abnormality, response to treatment or organ function and morphology. Therefore, through USG are provide substantial information to the practical and research veterinarian and assists in the definition of prognostics, treatments, culling and on the acquisition of breeding males and females without acquired or congenital reproductive disorders.(AU)

Diagnóstico ultrassonográfico de distúrbios reprodutivos em pequenos ruminantes / Ultrasonographic diagnosis of reproductive disorders in small ruminants

A ultrassonografia (USG) é uma técnica de imagem em tempo real e pouco invasiva. Na produção de ovinos e caprinos, a USG vem sendo utilizada como uma ferramenta auxiliar no manejo reprodutivo, assim como no diagnóstico clínico-reprodutivo de doenças ginecológicas, obstétricas e andrológicas. Por meio da USG é possível a realização de exames em série para monitorar a progressão de uma anormalidade, resposta ao tratamento ou a funcionalidade e morfologia do órgão. Assim, por meio da USG são fornecidas informações substanciais ao profissional do campo e da pesquisa auxiliando na definição de prognósticos, tratamentos, descarte zootécnico e, ainda, na aquisição de reprodutores e matrizes sem distúrbios reprodutivos adquiridos ou congênitos.

Ultrasonography (USG) is a less invasive, real-time imaging modality. In the sheep and goat farming, USG has been used as an auxiliary tool in the reproductive management, as well as in the clinical-reproductive diagnosis of gynecological, obstetric and andrological disorders. Through the USG, it is possible to perform successive evaluations to monitor the progression of an abnormality, response to treatment or organ function and morphology. Therefore, through USG are provide substantial information to the practical and research veterinarian and assists in the definition of prognostics, treatments, culling and on the acquisition of breeding males and females without acquired or congenital reproductive disorders.

Mini-Percoll technique induces similar capacitation features in domestic ruminant frozen-thawed spermatozoa regardless of the presence of heparin

Background: Sperm capacitation is a process consists of a series of functional, biochemical, and biophysical modificationsthat render the ejaculated sperm competent for oocyte fertilization. Secreted by the female reproductive tract epithelium,heparin promotes capacitation by binding to and removing seminal plasma proteins, which are adsorbed to the sperm PMand would inhibit capacitation. There is substantial evidence that cryopreservation promotes capacitation-like changes inbull, ram and buck sperm. Our general hypotheses were: (a) cryopreserved ram sperm suffer capacitation more quicklythan buck and bull sperm under the same conditions; (b) the capacitation status of ruminant cryopreserved sperm is similarwhether or not heparin is present after the mini-Percoll technique; and (c) ruminant frozen-thawed sperm selected by miniPercoll and incubated within media without heparin supplementation is not impaired in terms of capacitation status andsperm agglutination. This study aimed to compare sperm parameters of ovine, caprine, and bovine frozen-thawed spermafter mini-Percoll processing followed by incubation with or without heparin supplementation.Materials, Methods & Results: Commercial semen of all species were used. Sperm samples were selected by mini-Percolland supplemented (or not) with heparin within an incubation medium for 18 h. Sperm kinematics (CASA system analyzes),capacitation status (CTC staining) and sperm agglutination were evaluated after thawing, mini-Percoll, 1.5 h, 3 h, 6 h and18 h. In comparison with post-thawing analysis, ovine species demonstrated a reduction (P < 0.05) in most of the spermmotility parameters after mini-Percoll. Conversely, ovine samples presented...

Mini-Percoll technique induces similar capacitation features in domestic ruminant frozen-thawed spermatozoa regardless of the presence of heparin

Background: Sperm capacitation is a process consists of a series of functional, biochemical, and biophysical modificationsthat render the ejaculated sperm competent for oocyte fertilization. Secreted by the female reproductive tract epithelium,heparin promotes capacitation by binding to and removing seminal plasma proteins, which are adsorbed to the sperm PMand would inhibit capacitation. There is substantial evidence that cryopreservation promotes capacitation-like changes inbull, ram and buck sperm. Our general hypotheses were: (a) cryopreserved ram sperm suffer capacitation more quicklythan buck and bull sperm under the same conditions; (b) the capacitation status of ruminant cryopreserved sperm is similarwhether or not heparin is present after the mini-Percoll technique; and (c) ruminant frozen-thawed sperm selected by miniPercoll and incubated within media without heparin supplementation is not impaired in terms of capacitation status andsperm agglutination. This study aimed to compare sperm parameters of ovine, caprine, and bovine frozen-thawed spermafter mini-Percoll processing followed by incubation with or without heparin supplementation.Materials, Methods & Results: Commercial semen of all species were used. Sperm samples were selected by mini-Percolland supplemented (or not) with heparin within an incubation medium for 18 h. Sperm kinematics (CASA system analyzes),capacitation status (CTC staining) and sperm agglutination were evaluated after thawing, mini-Percoll, 1.5 h, 3 h, 6 h and18 h. In comparison with post-thawing analysis, ovine species demonstrated a reduction (P < 0.05) in most of the spermmotility parameters after mini-Percoll. Conversely, ovine samples presented...(AU)

Comparison of different sperm selection techniques in ram frozen-thawed sperm

Background: The success of fertilization is directly associated with semen quality and the sperm preparation. Considering the common use of cryopreserved spermatozoa, there is a need to develop strategies for sperm preparation in order to achieve a sperm sample of high quality through a rigorous selection of sperm. Thus, sperm cells are being more extensively investigate. This study aimed evaluating the influence of different sperm selection techniques on ram sperm parameters in semen preparation.Materials, Methods & Results: Frozen-thawed commercial semen from 10 Santa Inês rams was subjected to either: swim-up, Percoll, mini-Percoll, sperm washing by centrifugation or a control group. After each technique, samples were incubated at 37o.C for 1 h, 2 h and 3 h. At post-selection moment (0 h) and at each interval, sperm recovery rate, motility, capacitation and plasma membrane (PM) integrity were analyzed. The lowest (P 0.05). Most part of motility parameters were not affected (P > 0.05) by the technique at 0 h; just swim-up obtained higher (P 0.05) capacitated [...]

Produção in vivo de embriões ovinos / In vivo production of ovine embryos

A presente revisão tem por objetivo abordar os aspectos técnicos em estudos nas diferentes etapas damúltipla ovulação e transferência de embriões em ovinos (MOTE). Apesar dos inúmeros avanços a altavariabilidade de resposta à superovulação ainda é um entrave para esta biotécnica. Visando driblar este gargalodiferentes estratégias têm sido testadas para selecionar fêmeas com melhor potencial de resposta, como acontagem de folículos antrais, pré-seleção com eCG, repetibilidade de resposta, dosagem do hormônio antiMüllerianoe sincronização da onda folicular. Ajustes de protocolos superovulatórios modificando a frequência,o número de aplicações e a diminuição da dose total de FSH, têm sido testados. Outra tendência é a substituiçãode procedimentos cirúrgicos por técnicas menos invasivas, prezando pelo bem estar animal e também pelasimplificação de processos. Resultados satisfatórios para avaliação de doadoras por ultrassonografia ao invés delaparoscopia ilustram esta tendência. Adicionalmente, a inovulação não cirúrgica já se mostra exequível. Porém,etapas como a seleção de receptoras e a criopreservação de embriões também têm potencial para melhorar osíndices. Associando os esforços e resultados de diferentes linhas de pesquisas, a MOTE em ovinos têm evoluídoe seu uso para pesquisa ou produção animal tem-se ampliado.(AU)

This review address technical aspects that are being studied in multiple ovulation and embryo transferin sheep (MOTE). Despite the numerous advances the high variability of response to superovulation still abarrier for this biotechnology. Aiming to suppress this limitation, different strategies have been tested to selectewes with high ovulatory response such as antral follicle count, pre-selection with eCG, repeatability ofresponse, anti-Müllerian hormone, and follicular wave synchronization. Adjustments of superovulatoryprotocols modifying the frequency, the number of applications and a decrease in the total FSH dose are alsobeing tested. Another trend is the replacement of surgical procedures for less invasive techniques, focusinganimal welfare and simplification of procedures. Satisfactory results using ultrasonography to evaluate donors,rather than laparoscopy illustrate this trend. Also non-surgical embryo transfer is already feasible in ewes.However, adjustments in recipients selection and embryo cryopreservation can potentially improve pregnancyrates. By linking the efforts and results of different lines of research, MOTE in sheep has improved and it is usefor research or animal production increased.(AU)

Sincronização e indução do estro em caprinos leiteiros / Synchronization and induction of estrus in dairy goats

A estacionalidade reprodutiva em caprinos enfraquece a cadeia produtiva e torna inconstante a receitaobtida. Produtores procuram utilizar protocolos hormonais ou metodologias naturais visando obter melhoresíndices produtivos. As cabras apresentam padrão de estacionalidade distinto de acordo com a latitude que seencontram no Brasil e fatores como a nutrição, interações sociais e aspectos climáticos parecem ser componentesimportantes. Na estação reprodutiva, a sincronização do estro é obtida pelo uso de agentes luteolíticosintervalados por sete ou 11,5 dias. Na contra estação, a indução do estro sincronizado é obtida por meio dedispositivos intravaginais contendo progestágenos mantidos por seis dias em associação a diferentesgonadotropinas, aplicadas de 48 a 24 h antes da retirada do dispositivo. Hormônios indutores de ovulaçãotambém podem ser adotados. Igualmente, é importante considerar o estado fisiológico e a capacidadereprodutiva dos machos. No repouso sexual, os mesmos podem ser estimulados pelo uso da melatonina, manejodo fotoperíodo, o bioestímulo por cabras em estro e a aplicação de eCG. Dentre as estratégias naturais, destacaseo uso do efeito macho, efeito fêmea, controle artificial do fotoperíodo e a associação entre estes visando apromoção de sistemas orgânicos e sustentáveis a partir de métodos verdes, éticos e limpos.(AU)

The reproductive seasonality in goats weakens the productive chain and makes inconstant the income obtained.In this way, farmers usually apply hormonal protocols or natural techniques in order to improve productiveindexes. Goats present a distinct seasonal pattern according to the latitude found in Brazil and factors asnutrition, social interactions and climate appear to be important components. In the reproductive season, estrussynchronization is achieved by the use of luteolytic agents as prostaglandin analogs at intervals of seven or 11.5days. The induction of synchronized estrus is obtained through intravaginal devices containing natural orsynthetic progestogens for six days in association with gonadotropins applied 48 to 24 hours before deviceremoval. Ovulation-inducing hormones can also be adopted. Similarly, it is important to consider thephysiological status and reproductive capacity of males. At the nonbreeding season, bucks can be stimulated bythe use of melatonin, photoperiod management, by does in estrus and the administration of eCG. Among thenatural strategies, it is important to highlight the male and female effect, artificial control of photoperiod andtheir association, aiming to promote organic and sustainable systems applying green, ethical and clean methods.(AU)

Comparison of different sperm selection techniques in ram frozen-thawed sperm

Background: The success of fertilization is directly associated with semen quality and the sperm preparation. Considering the common use of cryopreserved spermatozoa, there is a need to develop strategies for sperm preparation in order to achieve a sperm sample of high quality through a rigorous selection of sperm. Thus, sperm cells are being more extensively investigate. This study aimed evaluating the influence of different sperm selection techniques on ram sperm parameters in semen preparation.Materials, Methods & Results: Frozen-thawed commercial semen from 10 Santa Inês rams was subjected to either: swim-up, Percoll, mini-Percoll, sperm washing by centrifugation or a control group. After each technique, samples were incubated at 37o.C for 1 h, 2 h and 3 h. At post-selection moment (0 h) and at each interval, sperm recovery rate, motility, capacitation and plasma membrane (PM) integrity were analyzed. The lowest (P < 0.05) recovery rate was recorded after swim-up (1.0 ± 0.3%), whilst the others were similar (P > 0.05). Most part of motility parameters were not affected (P > 0.05) by the technique at 0 h; just swim-up obtained higher (P < 0.05) values for VSL (41.8 ± 11.1) and VAP (46.9 ± 11.2). Overall, swim-up presented higher (P < 0.05) values for most of motility parameters over time of incubation. The control group led to more (P > 0.05) capacitated [...](AU)

Produção in vivo de embriões ovinos / In vivo production of ovine embryos

A presente revisão tem por objetivo abordar os aspectos técnicos em estudos nas diferentes etapas damúltipla ovulação e transferência de embriões em ovinos (MOTE). Apesar dos inúmeros avanços a altavariabilidade de resposta à superovulação ainda é um entrave para esta biotécnica. Visando driblar este gargalodiferentes estratégias têm sido testadas para selecionar fêmeas com melhor potencial de resposta, como acontagem de folículos antrais, pré-seleção com eCG, repetibilidade de resposta, dosagem do hormônio antiMüllerianoe sincronização da onda folicular. Ajustes de protocolos superovulatórios modificando a frequência,o número de aplicações e a diminuição da dose total de FSH, têm sido testados. Outra tendência é a substituiçãode procedimentos cirúrgicos por técnicas menos invasivas, prezando pelo bem estar animal e também pelasimplificação de processos. Resultados satisfatórios para avaliação de doadoras por ultrassonografia ao invés delaparoscopia ilustram esta tendência. Adicionalmente, a inovulação não cirúrgica já se mostra exequível. Porém,etapas como a seleção de receptoras e a criopreservação de embriões também têm potencial para melhorar osíndices. Associando os esforços e resultados de diferentes linhas de pesquisas, a MOTE em ovinos têm evoluídoe seu uso para pesquisa ou produção animal tem-se ampliado.

This review address technical aspects that are being studied in multiple ovulation and embryo transferin sheep (MOTE). Despite the numerous advances the high variability of response to superovulation still abarrier for this biotechnology. Aiming to suppress this limitation, different strategies have been tested to selectewes with high ovulatory response such as antral follicle count, pre-selection with eCG, repeatability ofresponse, anti-Müllerian hormone, and follicular wave synchronization. Adjustments of superovulatoryprotocols modifying the frequency, the number of applications and a decrease in the total FSH dose are alsobeing tested. Another trend is the replacement of surgical procedures for less invasive techniques, focusinganimal welfare and simplification of procedures. Satisfactory results using ultrasonography to evaluate donors,rather than laparoscopy illustrate this trend. Also non-surgical embryo transfer is already feasible in ewes.However, adjustments in recipients selection and embryo cryopreservation can potentially improve pregnancyrates. By linking the efforts and results of different lines of research, MOTE in sheep has improved and it is usefor research or animal production increased.

Sincronização e indução do estro em caprinos leiteiros / Synchronization and induction of estrus in dairy goats

A estacionalidade reprodutiva em caprinos enfraquece a cadeia produtiva e torna inconstante a receitaobtida. Produtores procuram utilizar protocolos hormonais ou metodologias naturais visando obter melhoresíndices produtivos. As cabras apresentam padrão de estacionalidade distinto de acordo com a latitude que seencontram no Brasil e fatores como a nutrição, interações sociais e aspectos climáticos parecem ser componentesimportantes. Na estação reprodutiva, a sincronização do estro é obtida pelo uso de agentes luteolíticosintervalados por sete ou 11,5 dias. Na contra estação, a indução do estro sincronizado é obtida por meio dedispositivos intravaginais contendo progestágenos mantidos por seis dias em associação a diferentesgonadotropinas, aplicadas de 48 a 24 h antes da retirada do dispositivo. Hormônios indutores de ovulaçãotambém podem ser adotados. Igualmente, é importante considerar o estado fisiológico e a capacidadereprodutiva dos machos. No repouso sexual, os mesmos podem ser estimulados pelo uso da melatonina, manejodo fotoperíodo, o bioestímulo por cabras em estro e a aplicação de eCG. Dentre as estratégias naturais, destacaseo uso do efeito macho, efeito fêmea, controle artificial do fotoperíodo e a associação entre estes visando apromoção de sistemas orgânicos e sustentáveis a partir de métodos verdes, éticos e limpos.

The reproductive seasonality in goats weakens the productive chain and makes inconstant the income obtained.In this way, farmers usually apply hormonal protocols or natural techniques in order to improve productiveindexes. Goats present a distinct seasonal pattern according to the latitude found in Brazil and factors asnutrition, social interactions and climate appear to be important components. In the reproductive season, estrussynchronization is achieved by the use of luteolytic agents as prostaglandin analogs at intervals of seven or 11.5days. The induction of synchronized estrus is obtained through intravaginal devices containing natural orsynthetic progestogens for six days in association with gonadotropins applied 48 to 24 hours before deviceremoval. Ovulation-inducing hormones can also be adopted. Similarly, it is important to consider thephysiological status and reproductive capacity of males. At the nonbreeding season, bucks can be stimulated bythe use of melatonin, photoperiod management, by does in estrus and the administration of eCG. Among thenatural strategies, it is important to highlight the male and female effect, artificial control of photoperiod andtheir association, aiming to promote organic and sustainable systems applying green, ethical and clean methods.