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.

Retirada de corpo estranho (dispositivo impregnado com progesterona) da cavidade abdominal de novilha da raça Jersey ­ relato de caso / Removal of a foreign body (progesterone impregnated device) from the abdominal cavity of a Jersey heifer ­ a case report / Extracción de cuerpo extraño (dispositivo impregnado con progesterona) de la cavidad abdominal de novilla raza Jersey - reporte de caso

A inseminação artificial em tempo fixo (IATF) é uma biotécnica com inúmeras vantagens para a produção de bovinos. Para a realização da IATF, as fêmeas bovinas devem receber um protocolo farmacológico que induz a ovulação de forma sincronizada. Esse protocolo inicia com a inserção de um dispositivo impregnado com progesterona que deve permanecer no fundo vaginal da fêmea por tempo determinado. O presente relato tem por objetivo descrever a remoção de um implante impregnado com progesterona que foi encontrado na cavidade abdominal de uma novilha. Durante um atendimento reprodutivo de rotina em uma propriedade rural, uma novilha da raça Jersey, recém-adquirida, com histórico de ter sido submetida à IATF, foi avaliada para diagnóstico de gestação. No exame a novilha não estava gestante e apresentava um cisto folicular ovariano. A novilha foi submetida novamente à IATF em que foi inserido e removido um implante, com isso o cisto regrediu e ao inseminar a novilha não foi possível passar a cérvix com o aplicador. Vinte dias após a inseminação a novilha manifestou estro e ao ser avaliada para nova inseminação, foi identificado um implante solto na cavidade abdominal da novilha. Foi realizada uma laparotomia pelo flanco esquerdo e o implante foi removido. Após a recuperação da cirurgia a novilha foi inseminada e novamente e ficou gestante. Os protocolos de IATF devem ser realizados por profissionais capacitados para evitar problemas como a presente situação em que um implante foi encontrado na cavidade abdominal de uma novilha.(AU)

The fixed-time artificial insemination (FTAI) is a biotechnique with numerous advantages for cattle production. In order to perform the FTAI, the cows must receive a pharmacological protocol to induce ovulation in a synchronized way. This protocol begins with the insertion of a device impregnated with progesterone that must remain in the vaginal fundus of the cow for a specific period of time. This report aims at describing the removal of a progesterone impregnated implant that was found in the abdominal cavity of a heifer. During a routine reproductive service in a rural property, a recently acquired Jersey heifer, with history of having been submitted to FTAI, was evaluated for pregnancy diagnosis. At the exam, it was observed that the heifer was not pregnant and presented an ovarian follicular cyst. The heifer was then submitted to FTAI again, where an implant was inserted and removed. This made the cyst to recede, and upon subsequent insemination, the applicator was not able to pass the cervix. Twenty days after insemination, the heifer was in estrus and when it was evaluated for insemination, a loose implant was identified in the abdominal cavity of the heifer. A laparotomy was performed through the left flank and the implant was removed. After recovery from the surgery, the heifer was inseminated again and became pregnant. The FTAI protocols should only be carried out by trained professionals to avoid problems such as the one presented herein, where an implant was found in the abdominal cavity of a heifer.(AU)

La inseminación artificial a tiempo fijo (FTAI) es una biotécnica con numerosas ventajas para la producción de ganado. Para realizar FTAI, las hembras bovinas deben recibir un protocolo farmacológico que induzca la ovulación de forma sincronizada. Este protocolo comienza con la inserción de un dispositivo impregnado con progesterona que debe permanecer en el fondo vaginal de la hembra durante un tiempo específico. Este informe tiene como objetivo describir la extracción de un implante impregnado de progesterona que se encontró en la cavidad abdominal de una novilla. Durante la atención reproductiva de rutina en una propiedad rural, se evaluó el diagnóstico de preñez de una novilla de Jersey recién adquirida con antecedentes de someterse a FTAI. En el examen, la novilla no estaba embarazada y tenía un quiste folicular ovárico. La novilla fue nuevamente sometida a FTAI, en la cual se insertó y removió un implante, con esto el quiste retrocedió y al inseminar a la novilla no fue posible pasar el cérvix con el aplicador. Veinte días después de la inseminación, la vaquilla manifestó estro y cuando se evaluó para una nueva inseminación, se identificó un implante suelto en la cavidad abdominal de la vaquilla. Se realizó una laparotomía a través del flanco izquierdo y se extrajo el implante. Después de recuperarse de la cirugía, la novilla fue inseminada y nuevamente quedó embarazada. Los protocolos FTAI deben ser realizados por profesionales capacitados para evitar problemas como la situación actual donde se encontró un implante en la cavidad abdominal de una novilla.(AU)

Plasma metabolite changes in anestrous dairy cows with negative energy balance identified using 1H NMR technology / [Alterações do metabólito plasmático em vacas leiteiras com balanço energético negativo identificado usando a tecnologia 1H NMR]

The objective of the present study was to investigate the different plasma metabolites between anestrus and estrus postpartum dairy cows and to provide a theoretical basis for prevention of anestrus in dairy farm cows. In the experiment, one hundred and sixty-seven Holstein dairy cows were selected with similar age and parity. According to the concentration of ß-hydroxybutyric acid, non-esterified fatty acids and glucose in plasma during 14 to 21 days in milk, all dairy cows were determined as having a status of energy balance. According to the results of clinical symptom, rectal and B ultrasound examination at 60 to 90 days postpartum, these cows were divided into twenty estrus and twenty-four anestrus group, other dairy cows were removed. 1H nuclear magnetic resonance technology was utilized to detect the plasma metabolites changes and screen different plasma metabolites between anestrus and estrus cows. Ten different metabolites including alanine, glutamic acid, asparagine, creatine, choline, phosphocholine, glycerophosphocholine, low-density lipoprotein, and very-low-density lipoprotein were significantly decreased in anestrous cows compared with estrous cows. Metabolic pathway analyses indicated that differential metabolites were primarily involved in amino acid and glycerophospholipid metabolism. These metabolites and their enrichment pathways indicate that reduced steroid hormone synthesis precursors result in lower levels of estradiol and progesterone and cause anestrus in negative energy balance. These data provide a better understanding of the changes that may affect estrus of postpartum dairy cows at NEB status and lay the ground for further research.(AU)

O objetivo do presente estudo foi investigar os diferentes metabolitos do plasma entre o cio e o cio pós-parto de vacas leiteiras e fornecer uma base teórica para a prevenção do cio de vacas em fazendas de leite. No experimento, foram selecionadas 127 vacas leiteiras Holstein com idade e paridade similares. De acordo com a concentração de ß- ácido hidroxibutírico, ácidos graxos não esterificados e glicose no plasma entre 14 e 21 dias no leite, todas as vacas leiteiras foram determinadas em estado de equilíbrio energético. De acordo com os resultados dos sintomas clínicos, do exame de ultra-som retal e B aos 60 a 90 dias pós-parto, estas vacas foram divididas em vinte cios e vinte e quatro grupos de cio, outras vacas leiteiras foram removidas. A tecnologia de ressonância magnética nuclear 1H foi utilizada para detectar as alterações dos metabólitos plasmáticos e para triar diferentes metabólitos plasmáticos entre as vacas do cio e do cio. Dez diferentes metabólitos incluindo alanina, ácido glutâmico, asparagina, creatina, colina, fosfocholina, glicerofosfocolina, lipoproteína de baixa densidade e lipoproteína de muito baixa densidade foram significativamente diminuídos nas vacas antróficas em comparação com as vacas estro. As análises da via metabólica indicaram que os metabólitos diferenciais estavam principalmente envolvidos no metabolismo de aminoácidos e glicerofosfolipídios. Estes metabólitos e suas vias de enriquecimento indicam que a redução dos precursores da síntese de hormônios esteróides resulta em níveis mais baixos de estradiol e progesterona e causa anestros no balanço energético negativo. Estes dados fornecem uma melhor compreensão das mudanças que podem afetar o cio das vacas leiteiras pós-parto no estado de NEB e preparam o terreno para mais pesquisas.(AU)

Effects of blood pathological changes before TAI on pregnancy of dairy cows with anestrus and estrus / [Efeitos de mudanças patológicas de plasma antes de (TAI) na gestação de vacas em anestro e estro]

The objective of this study was to investigate the influence of plasma pathological changes before timed artificial insemination (TAI) on pregnancy of cows. The contents of estrogen (E2), progesterone (P4), glucose (Glu), selenium (Se), brain-derived neurotrophic factor (BDNF), and histamine (HIS) in plasma of 48 Holstein cows were measured before TAI. According to the estrus detection, the cows were divided into estrus (E) and anestrus (A) groups. After pregnancy testing at 28 d after TAI, two groups of E and A were divided into positive pregnancy of E group (EP+), negative pregnancy of E group (EP-), positive pregnancy of A group (AP+), and negative pregnancy of A group (AP-). The contents of E2, P4, Glu, Se, BDNF and hIS significantly differed among the four groups (P<0.01). The ROC analysis was used to determine the risk of negative pregnancy test (-) after TAI was increased when plasma E2 was less than 46.45 pmol/L in cows before TAI. The changes in E2, P4,hIS, Glu, and BDNF in the blood of natural estrus and natural anestrus cows affected the pregnancy after TAI. the level of E2 in plasma may be used to assess the risk of negative pregnancy after TAI.(AU)

O objetivo do presente estudo foi investigar a influência de mudanças patológicas de plasma antes de inseminação artificial (TAI) na gestação de vacas. O conteúdo de estrogênio (E2), progesterona (P4), glucose (Glu), selênio (Se), fator neurotrófico derivado do cérebro (BDNF), e histamina (HIS) no plasma de 48 vacas Holstein foi medido antes de TAI. De acordo com a detecção de estro, as vacas foram divididas em dois grupos: estro (E) e anestro (A). Após teste de gestação 28 d após TAI, dois grupos de E e A foram formados em gestação positiva do grupo E (EP+), gestação negativa do grupo E (EP-), gestação positiva do grupo A (AP+), e gestação negativa do grupo A (AP-). Os valores de E2, P4, Glu, Se, BDNF e hIS foram significativamente diferentes entre os quatro grupos (P<0,01). A análise ROC foi utilizada para determinar o risco de teste de gestação negativo (-) após aumento de TAI quando plasma E2 estava abaixo de 46,45 pmol/L em vacas antes de TAI. Alterações em E2, P4,hIS, Glu e BDNF no sangue de estro natural e anestro natural em vacas afetou a gestação após TAI. O nível de E2 no plasma pode ser usado para avaliar o risco de gestação negativa após TAI.(AU)

The effect of Gonadotropin releasing hormone administration on fertility and embryonic loss in goats during the anoestrus period

Following the induction of oestrus out of season in small ruminants, low fertility and variations in fertility rates are associated with embryonic losses. One of the main causes of embryonic loss is luteal dysfunction. Gonadotropin Releasing Hormone (GnRH) supports the luteal structure, and increasing progesterone levels may be beneficial in terms of promoting embryonic life. The main objective of the present study was to evaluate the efficacy of GnRH administration following an oestrus induction protocol in the anoestrus season for preventing embryonic loss in goats having failure to conceive during the season. In the study, 106 Damascus goats aged 3-5 years and weighing 45-60 kg were used. The oestrus of 106 goats in the anoestrous group was stimulated with progesterone and pregnant mare serum gonadotropin (PMSG) treatment. Out of breeding season, goats were divided into the 4 following groups: GnRH0 (n = 27), GnRH7 (n = 26), GnRH0+7 (n = 27) and control (n = 26). In each goat, an intravaginal sponge (IS) containing 20 mg of fluorogestone acetate (FGA) was placed into the vagina and left for 9 days. With the withdrawal of the sponge, 550IU PMSG and 125 µg of d-cloprostenol were injected intramuscularly. Oestrus detection was made via teaser bucks for 3 days starting 24 h after withdrawal of the IS. Eighteen bucks known to be fertile were used for breeding. Goats in the oestrus period were mated via natural breeding. The GnRH analogue lecirelin was injected intramuscularly at breeding in the GnRH0 group, on day 7 post-breeding in the GnRH7 group, and both at breeding and on day 7 post-breeding in the GnRH0+7 group. No injections were given to the control group. Blood samples for progesterone measurement were taken by jugular vena puncturing on days 3, 6, 7, 10, 13, 16, and 19 after breeding from 10 randomly chosen goats in all groups. The goats with a level of > 3.5 ng/mL of progesterone on day 21 post-breeding were evaluated as pregnant. Pregnancy was also viewed on day 50 after breeding by real-time ultrasonography (USG) with a 5-7.5 MHz convex probe. The oestrus rate was 96.23% (102/106) in the goats. The rates of onset of oestrus between 36-48 h, 48-60 h and 60 h and beyond were 38.7% (41/106), 21.7% (23/106) and 35.8% (38/106), respectively. The total pregnancy rate was 35.8% (38/106). There were no statistically significant differences (P > 0.05) found for the pregnancy rate, embryonic death rate or progesterone concentration of the groups. However, serum progesterone levels were statistically different in the GnRH7 group compared with the control group (P < 0.05). After synchronisation, various anti-luteolytic strategies can be used to support corpus luteum development and elevate progesterone concentration in the luteal phase to decrease embryonic loss and increase reproductive performance. Therefore, application of GnRH to support the luteal structure and to increase progesterone levels may be beneficial in terms of supporting embryonic life. The results showed that GnRH treatment on the day 7 post-breeding following oestrus induction, including FGA and PMSG, can increase serum progesterone levels in Damascus goats in the anoestrus period. However, following oestrus induction in the anoestrus period, it was seen that GnRH treatment at breeding or on day 7 after breeding did not have any positive effect on embryonic loss or reproductive performance. In conclusion, it was considered that this protocol could be implemented successfully, yielding a 35% pregnancy rate in Damascus goats in the anoestrus period, but embryonic loss must be deeply studied in detail.(AU)

O uso do cloridrato de piridoxina para induzir estro em cadelas / The use of pyridoxine chloridrate to induce estrus in female dogs

Os agonistas dopaminérgicos são utilizados para induzir estro em cadelas, pois atuam na síntese e liberação de prolactina. Objetivou-se avaliar o efeito da piridoxina como indutor de estro em cadelas por agir na neurotransmissão dopaminérgica. Foram selecionadas 40 cadelas em anestro, divididas em quatro grupos experimentais, tratadas com 10mg/kg/dia (G1) e 50mg/kg/dia (G2) de cloridrato de piridoxina, 5µg/kg/dia (G3) de cabergolina e grupo controle/placebo (G4) por até 20 dias. Foram realizadas citologias vaginais a cada 24h para acompanhamento do ciclo estral e análises hormonais (FSH, LH e PRL) no dia zero e 120h do início do tratamento. As cadelas do G3 (100%) manifestaram proestro após 12 dias de tratamento aproximadamente, tempo inferior aos demais grupos (P<0,05). Apenas uma cadela do G1 e uma do G2 ficaram gestantes contra oito fêmeas do G3 e nenhuma do G4 (P<0,05). As concentrações plasmáticas de prolactina foram reduzidas nas fêmeas do G2 e G3 (P<0,05). As demais avaliações hormonais não sofreram influência do tratamento (P>0,05). O cloridrato de piridoxina foi ineficiente para induzir estro em cadelas, mas foi capaz de suprimir a prolactina, de forma semelhante à cabergolina, quando utilizado na dose de 50mg/kg/dia.(AU)

Dopaminergic agonists are used to induce estrus in female dogs as they act in the synthesis and release of prolactin. The objective of this study was to evaluate the effect of pyridoxine as an inducer of estrus by acting on dopaminergic neurotransmission. A total of 40 female dogs in anestrous were divided into four experimental groups treated with 10mg/kg/day (G1) and 50mg/kg/day (G2) of pyridoxine hydrochloride, 5µg/kg/day (G3) of cabergoline and control group/placebo (G4) for up to 20 days. Vaginal cytologies were performed every 24h for follow-up of the estrous cycle and hormonal analyzes (FSH, LH and PRL) on day zero and 120 hours after the start of treatment. The female dogs from G3 (100%) showed proestrus after 12 days of treatment, less time than the other groups (P< 0.05). Only one female from G1 and one from G2 were pregnant against eight from G3 and none from G4 (P< 0.05). Plasma concentrations of prolactin were reduced by treatment in females from G2 and G3 (P< 0.05). The other hormonal evaluations were not influenced by the treatment (P> 0.05). Pyridoxine chloridrate was inefficient to induce estrus in female dogs but was able to suppress prolactin when used at a dose of 50mg/kg/day.(AU)

Effects of anastrozole on Ki-67 antigen expression in the vaginal epithelium of female rats in persistent estrus

OBJECTIVES: Aromatase inhibitors are the first-choice drugs for the treatment of hormone sensitive breast cancer. However, in addition to the scarcity of studies, there are controversies about their effects on vaginal epithelial cell proliferation in rats, especially those in persistent estrus. METHODS: To investigate vaginal epithelial cell proliferation by Ki-67 antigen expression, persistent estrus was induced in 42 randomly selected rats. These rats were randomly divided into 2 groups: group I (control, n=21), which received 0.1 mL of propylene glycol (vehicle) daily, and group II (experimental, n=21), which received 0.5 mg/kg or 0.125 mg/day of anastrozole diluted with 0.1 mL of propylene glycol. RESULTS: Light microscopy showed a higher concentration of cells with brown Ki-67 stained nuclei in the control compared to the experimental group. The mean percentage of Ki-67 stained nuclei per 500 cells in the vaginal epithelium was 68.64±2.64 and 30.46±2.00 [mean±standard error of the mean (SEM)] in the control and experimental groups, respectively (p<0.003). CONCLUSION: This study showed that anastrozole, at the dose and treatment duration selected, significantly decreased cell proliferation in the vaginal mucosa of the rats in persistent estrus.

Melatonin may prevent or reverse polycystic ovary syndrome in rats

SUMMARY OBJECTIVE To evaluate the ovarian effects of melatonin (Mel) in a rat model of polycystic-ovary-syndrome (PCOS) before and after permanent estrus induction. METHODS Thirty-two adult-female rats with regular estrous cycle were equally divided into four groups: 1) GCtrl - at estrous phase. 2) GPCOS - at permanent-estrous phase. 3) GMel1 - treated for 60 days with Mel (0.4 mg/Kg) during permanent estrus induction and 4) GMel2 - rats with PCOS and treated for 60 days with Mel. After that, the animals were euthanized, and the ovaries were removed and processed for paraffin embedding. Sections were stained with H.E. for histomorphometry or subjected to immunohistochemistry for Ki-67 and cleaved caspase-3 (Casp-3) detections. RESULTS The GPCOS showed lack of corpus luteum and several ovarian cysts, as well as interstitial-like cells. The presence of corpus luteum and a significant increase in primary and antral follicles were observed in Mel-treated groups, which also showed a decrease in the number of ovarian cysts and in the area occupied by interstitial-like cells. These results were more evident in GMel1. The percentage of Ki-67-positive cells was significantly higher in the Mel-treated groups, mainly in the GMel2, as compared to GPCOS. On the other hand, the percentage of Casp-3-positive cells was significantly lower in granulosa cells of GMel1, whereas it was significantly higher in the interstitial-like cells of GMel2, in comparison to GPCOS. CONCLUSION Melatonin administration prevents the permanent estrus state in the PCOS rat model. This effect is more efficient when melatonin is administered before permanent estrus induction.

RESUMO OBJETIVO Avaliar os efeitos ovarianos da melatonina (Mel) em ratas com síndrome dos ovários policísticos (SOP) antes e após a indução do estro-permanente. MÉTODOS Trinta e duas ratas com ciclos estrais regulares foram igualmente divididas em quatro grupos: 1) GCtrl - fase de estro. 2) GSOP - fase de estro-permanente. 3) GMel1 - tratadas por 60 dias com Mel (0,4 mg/kg) durante a indução do estro-permanente e 4) GMel2 - ratas com SOP e tratadas com Mel. Após eutanásia dos animais, os ovários foram processados para inclusão em parafina. Cortes foram corados com H.E ou submetidos à imuno-histoquímica para detecção de Ki-67 e caspase-3 clivada (Casp-3). RESULTADOS O GSOP mostrou ausência de corpos lúteos e vários cistos ovarianos, além de inúmeras células intersticiais. A presença de corpos lúteos e o aumento significativo dos folículos primários e antrais foram observados nos grupos tratados com Mel, os quais também mostraram diminuição no número de cistos ovarianos e na área ocupada pelas células intersticiais. Esses resultados foram mais evidentes no GMel1 do que no GMel2. A porcentagem de células Ki-67 positivas foi significativamente maior no GMel1 e no GMel2, sendo mais evidente no GMel2, em comparação ao GSOP. Por outro lado, a porcentagem de células positivas à Casp-3 foi menor nas células da granulosa do GMel1 e maior nas células intersticiais do GMel2, em comparação ao GSOP. CONCLUSÃO A administração de melatonina previne o estado de estro-permanente em ratas com SOP. Esse efeito é mais eficiente quando a melatonina é administrada após indução do estado de estro-permanente.

Efeito do óleo essencial do Croton nepetifolius Baill na penetração cervical em ovelhas mestiças de Dorper e Santa Inês / Effect of the essential oil of Croton nepetifolius Baill on cervical penetration in crossbred Dorper and Santa Inês ewes

A fim de se avaliar o uso do óleo essencial de Croton nepetifolius Baill (OECn) na penetrabilidade cervical em ovelhas mestiças, 40 ovelhas foram distribuídas ao acaso em quatro grupos (n=10): controle, misoprostol, OECn50 e OECn100 (50 e 100µg do OECn, respectivamente). Após a sincronização do estro, utilizando CIDR e eCG (200UI), a profundidade de penetração da cérvix foi mensurada utilizando-se uma pipeta de inseminação artificial de bovino graduada, no período de zero até 72h após a retirada do CIDR. Os resultados foram expressos em média ± erro-padrão, submetidos à ANOVA seguida do teste de Tukey, enquanto os dados, em porcentagem, foram submetidos aos testes de Fisher ouqui-quadrado. Nenhuma diferença significativa (P>0,05) foi encontrada quanto ao grau de penetrabilidade cervical. Quanto ao tempo de passagem, os grupos misoprostol e OECn100 apresentaram um menor tempo de penetrabilidade às 60h(1,7±0,6 e 1,5±0,6min, respectivamente), quando comparados ao grupo controle (4,1±0,6min), que não diferiu significativamente do grupo OECn50 (2,3±0,6min). Portanto, o óleo essencial de Croton nepetifolius Baill pode ser utilizado para encurtar o tempo de penetrabilidade cervical em ovelhas submetidas à sincronização estral.(AU)

In order to evaluate the use of the essential oil of Croton nepetifolius Baill (EOCn) on cervical penetration in crossbred ewes, 40 ewes were randomly allocated into four groups (n= 10): CONTROL, MISOPROSTOL, EOCn50 and EOCn100 (50 e 100µg of the EOCn, respectively). After estrus synchronization, using CIDR and eCG (200IU), depth of cervical penetration was measured using artificial insemination gun for bovine species which was graduated and used from 0 to 72h after CIDR removal. Results were expressed as mean ± standard error mean, submitted to ANOVA and Tukey test while data in percentage were submitted to Fisher or Chi-Square test. No significant difference (P> 0.05) was observed at grade of cervical penetration. Concerning trespassing time, MISOPROTOL and EOCn100 groups presented a lower trespassing time at 60h (1.7±0.6 and 1.5±0.6min, respectively) than CONTROL group (4.1±0.6min), which did not differ significantly from EOCn50 (2.3±0.6min) group. Therefore, the essential oil of Croton nepetifolius Baill can be used to shorten the cervical penetration time in estrus synchronized ewes.(AU)

Immunoexpression of vascular endothelial growth factor and B-cell lymphoma 2 in the uterine tissue of rats treated with melatonin in the estrus phase

Abstract Purpose: To investigate the effect of melatonin on uterine tissue in the ovariectomized rat model. Methods: Fourty Wistar albino rats were divided into four groups for histologic and immunohistochemical examination. The rats were first numbered randomly and then randomly divided into 4 equal groups: control (group 1), torsion (group 2), torsion+detorsion (group 3) and torsion+detorsion+melatonin (group 4) groups. In addition, four Wistar albino rats were used for western blot analysis in each group. And also, malondialdehyde (MDA) levels were measured biochemically in all rats. Results: The histopathological examination of the uterine tissue in rats ovarectomized showed a degeneration in uterine glands, dilation of blood vessels in the internal layer with a thrombosis and bleeding, abnormal nucleuses and vacuolated cytoplasm above and below the nucleus. In torsion group, the apoptotic cells increased in luminal epithelium and gland cells. In the melatonin group showed that the Bcl2 negative effect on the uterine epithelium and did not lead to apoptotic cells. Conclusion: The increase in vascular endothelial growth factor expression resulted in the rearrangement of endothelial cell growth and the induction of angiogenesis.

Pretentious genomic selection signatures in CYP19A1 gene associated with silent estrous behavior in water buffalo in Pakistan

Background: Poor reproductive efficiency of river buffalos hampers the production capabilities of animals. Buffalos are mainly considered poor breeders owing to the constrained expression of estrus behavior. Failure to display heat signs is an indication of improper functionality of signaling peptides to trigger on a series of behavioral changes, which can be detectable by breeders for timely insemination of females. This might cause an animal to be a repeat breeder. Genomic variations underlying synthesis of signaling peptides can be a useful marker to select superior animals with better reproductive efficiency. In this context, the current study was designed to analyze the CYP19A1 gene in Nili-Ravi buffalo. Results: A total of 97 animals were selected and were divided into two groups on the basis of their heat score. PCR amplification and sequencing of the amplicons were performed using the specific sets of primer, and then, sequences were analyzed for novel variants. A total of 11 polymorphic sites were identified illustrating phenotypic variation in the heat score. Most of the loci were found homologous. Single Nucleotide Polymorphisms (SNPs) were analyzed for association with silent estrus. A three-dimensional protein model was also generated to locate the position of exonic SNPs. Conclusion: This study illustrated that polymorphic sites in the CYP19A1 gene provided potential markers for selection of buffalos with better estrus behavior.

Use of a GnRH synthetic analog (buserelin) for estrous induction in female dogs / Utilização de análogo sintético de GnRH (buserelina) na indução do estro em cadelas

The aim of this study was to evaluate the effectiveness of a GnRH synthetic analog, as an estrous inducer in female dogs when administered during the anestrous phase, and to evaluate the pregnancy rate achieved through natural copulation. For this purpose, ten female dogs of different breeds were used. The subjects received buserelin by intramuscular injections at a dose of 2,1mcg when female dogs weighed up to 10kg (Group 1) and of 4,2mcg when the dogs weighed above 10kg (Group 2). Of the ten subjects, only three presented estrus after a single injection of buserelin: two dogs from Group 1 and one dog from Group 2 on average 7±1.29 days. The remaining seven dogs were given a second dose of buserelin, equal to the first administration. Of these, three belonged to Group 1 and four to Group 2. Four of these dogs exhibited clinical signs of estrus within, on average 9±7.3 days from the second injection. The seven female dogs that did enter estrus were fertilized successfully through natural copulation. The administration of buserelin was effective in inducing estrus in female dogs during the anestrous phase, with a maximum of two administrations.(AU)

Objetivou-se avaliar a eficácia de um análogo sintético ao GnRH como indutor de estro em cadelas em anestro e a taxa de prenhez por meio de cópula natural. Para isso, foram utilizadas 10 fêmeas caninas de diferentes raças. Cadelas de até 10kg de peso (grupo 1) foram submetidas à administração de buserelina por via intramuscular, na dose de 2,1mcg, e cadelas acima de 10kg (grupo 2) foram submetidas à mesma medicação, porém na dose de 4,2mcg. Das fêmeas em anestro, apenas três apresentaram estro com apenas uma aplicação, sendo duas do grupo 1 e uma do grupo 2, em 7±1,29 dias, em média. Em sete cadelas foi administrada mais uma dose de buserelina; destas, quatro eram pertencentes ao grupo 2 e três eram do grupo 1. Os sinais de estro ocorreram, em média, após 9±2,73 dias da segunda aplicação. As sete cadelas que manifestaram estro foram fertilizadas por meio de cópula natural. A administração de buserelina é eficiente para a indução de estro, em cadelas em anestro, em, no máximo, duas aplicações.(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)

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)

Citocentrifugação e métodos convencionais na citologia uterina de éguas em estro e diestro / Cytocentrifugation and conventional methods in endometrial cytology of estrus and diestrus mares

A citologia uterina consiste em método prático e eficiente para o diagnóstico de afecções uterinas na égua, contribuindo para a conduta terapêutica e o prognóstico quanto à fertilidade das fêmeas. Assim, o objetivo deste trabalho foi comparar diferentes técnicas de coleta de material para citologia uterina em éguas, a fim de se verificarem possíveis diferenças qualitativas e quantitativas e a praticidade na execução das metodologias. Para tanto, 12 éguas multíparas foram submetidas ao exame citológico uterino, durante o estro e o diestro, por meio de escova ginecológica e lavado uterino de baixo volume. Com esse ensaio, observou-se que não houve diferença significativa (P>0,05) no resultado da citologia uterina entre as diferentes técnicas avaliadas. No entanto, quando comparadas as fases do ciclo estral, houve uma diferença significativa (P<0,05) quanto ao percentual médio de polimorfonucleares neutrófilos, sendo de 8,07±2,80 no estro e de 1,55±0,28 no diestro. Conclui-se, desse modo, que as técnicas estudadas apresentaram resultados igualmente eficazes para detecção de neutrófilos ao exame citológico do útero em ambas as fases avaliadas do ciclo estral, apesar de, na fase de estro, a detecção de maior percentual de neutrófilos possibilitar um diagnóstico e um prognóstico mais precoces de endometrite e, portanto, uma conduta terapêutica mais adequada.(AU)

The endometrial cytology consists in an efficient and practical method for the diagnosis of uterine disorders in mares, contributing for therapeutic conduct and prognostic evaluation regarding the females' fertility. Therefore, the aim of this study was to compare different techniques of material sampling for endometrial cytology in mares, in order to verify possible qualitative and quantitative differences in the practicality of implementation of this methodology. Twelve multiparous mares underwent an endometrial cytological exam, during estrus and diestrus, by means of a cytobrush and a low-volume uterine flush. With this test, no statistical difference was observed (P>0.05) regarding the result of endometrial cytology between the evaluated techniques. However, in comparison to the estrous cycle's phases, a significant difference was verified (P<0.05) on the average percentage of polymorphonuclear neutrophils: 8.07±2.80 in estrus and 1.55±0.28 in diestrus. Thus, we conclude that the studied techniques presented equally effective results for the detection of neutrophils in the cytological exam for both evaluated stages of the estrous cycle, whereas in estrus phase, the detection of a higher percentage of neutrophils allows a more precocious diagnostic and prognostic of endometritis and, therefore, a more adequate therapeutic approach.(AU)

Synchronization of estrus in paca (Cuniculus paca L. ): possible impacts on reproductive and productive parameters / Sincronização do estro em pacas (Cuniculus paca L. ): possíveis impactos sobre parâmetros reprodutivos e produtivos

Estrus synchronization is a reproductive biotechnology used to improve artificial insemination or pairing through the manipulation of the estrous cycle at a desirable time. Employing this technique in captive pacas (Cuniculus paca L.) is important because it creates expectation of meeting the demand for paca meat and, consequently, reduces poaching. Thus, this research aims to verify the effect of a progestogen implant associated with two doses of eCG on the synchronization and induction of fertile estrus. Twenty-seven adult pacas were used, 18 non-pregnant females and nine males, divided into three groups. G1 and G2 females groups (treatments) received 1.5 mg Norgestomet and were injected intramuscularly, seven days later, with 0.13 mg of prostaglandin. After 24 hours the implants were removed and the animals immediately received 25 IU and 50 IU of ECG intramuscularly, respectively. The mating of the three groups took place on the same days. G3 females' group (control) showed estrus on different days after D0. Females under treatment displayed estrus only after removing the implant (D8). G1, G2, and G3 pregnancy rates were 100%, 66%, and 50%, respectively. Regarding births per parturition, 100% of G1 and G3 produced one offspring, while 50% of G2 produced two. Progestogen in the form of subcutaneous implants was effective in mimicking the luteal phase of the estrous cycle. After removal, implants favored the occurrence of a fertile estrus. As a conclusion, further studies must be conducted in order to establish in-depth possible association between 50 IU of eCG, and the occurrence of twin pregnancies.(AU)

A sincronização é uma biotécnica reprodutiva que melhora a porcentagem de cobertura por meio da manipulação do ciclo estral. Empregar esta biotécnica em pacas de cativeiro (Cuniculus paca L.) é importante, pois cria-se a expectativa de que a demanda pela carne seja atendida e a caça ilegal diminua. O objetivo da pesquisa foi verificar o efeito de implantes de progestágenos associados a duas doses de gonadotrofina coriônica equina (eCG) na sincronização e indução de cios férteis de pacas. Foram utilizadas 18 fêmeas não prenhas e nove machos, divididos em três grupos. Fêmeas do G1 e G2 receberam implantes com 1,5mg de Norgestomet e, sete dias depois, 0,13mg de prostaglandina via intramuscular (IM). No dia 8 (D8), foram retirados os implantes e G1 e G2 receberam 25 UI e 50 UI de eCG, IM, respectivamente; G3 foi o controle. O pareamento nos três grupos aconteceu nos mesmos dias. As fêmeas do G3 apresentaram cio alguns dias após o dia zero (D0). Fêmeas que receberam tratamento apresentaram cio só após a retirada do implante no dia 8 (D8). As taxas de prenhez de G1, G2 e G3 atingiram 100%, 66% e 50%, respectivamente. Em relação a filhotes por parto, 100% do G1 e G3 produziram uma cria, enquanto 50% do G2 produziram duas crias. O progestágeno do implante foi eficaz em mimetizar a fase lútea do ciclo estral. Após a remoção, o tratamento hormonal favoreceu a ocorrência de cio fértil. Outros estudos devem ser realizados a fim de estabelecer uma possível associação entre 50 UI de eCG e a ocorrência de gestações gemelares.(AU)

Profile of plasmatic progesterone on pregnancy, and the postpartum estrus of Dasyprocta prymnolopha (Rodentia: Dasyproctidae) / Perfil de la progesterona plasmática durante durante la preñez y celo posparto del Dasyprocta prymnolopha (Rodentia: Dasyproctidae)

Abstract:The agouti (Dasyprocta sp.) is a hystricomorph rodent found in some regions of the Americas. It is an important cynegetic species, which indicates that the overhunting is a threat to their conservation. Very little is known about this wildlife in relation to what already has been studied in domestic animals. Thus, the knowledge on reproduction of wildlife becomes necessary and essential for the management and conservation of these natural resources. Specifically, studies regarding hormonal monitoring are important as a basic tool for research in modern reproductive biotechnology, and currently, there is no information on the progesterone changes during pregnancy of Dasyprocta sp., compared to other hystricomorphs. The aim of this study was to describe the profile of plasmatic progesterone during pregnancy, and report the restart of ovarian cycle in agouti after parturition. For this purpose, 18 black-rumped agoutis (Dasyprocta prymnolopha) born in captivity were used, and one or more consecutive pregnancies were observed. Copulation was confirmed by the presence of spermatozoa observed in the colpocytological examination. Blood samples were collected two times per week, and concentrations of progesterone, assessed in ten agoutis, were determined by radioimmunoassay. The onset of ovarian activity in six females was observed daily by colpocytological examination, starting on the seventh day postpartum. The gestational period observed in this study was 104.04 days (SD = 1.31) (101-106 days) (Number of cases, N = 26), and the interval between births was 126.03 days (SD = 18.40) (109-184 days). The plasmatic profile of progesterone during pregnancy showed a progressive increase from the 1st to the 5th week. The higher progesterone levels over this period (6.88 ng / mL, SD = 3.01) were detected in the 5th week. This value was similar (One-Way ANOVA, p > 0.05) to that observed in the 4th and 6th weeks, but was statistically different (One-Way ANOVA, p < 0.05) when compared to the other weeks. After the 6th week there was a progressive decrease in plasmatic progesterone levels. The animals showed a postpartum estrus of 12.04 days (SD= 4.29) (7-24 days) (N= 23). It was observed that 80.95 % (N= 19) of copulations during this period were fertile. This work contributed to understanding the dynamic changes in the progesterone levels during the pregnancy in agouti. Nevertheless, more studies are needed for a better appreciation of other endocrine and biological changes, in the mother and feto-placental unit of the agouti. Rev. Biol. Trop. 64 (4): 1519-1526. Epub 2016 December 01.

Resumen:El agouti (Dasyprocta sp.) es un roedor histricomorfo encontrado en algunas regiones de América. Es una especie cinegética importante, lo que indica que la caza excesiva es una amenaza para su conservación. Muy poco es lo que se conoce acerca de la biología de los animales silvestres, en relación al conocimiento acumulado sobre los domésticos. Por lo tanto, el estudio sobre la reproducción de los animales silvestres se hace necesario e imprescindible para el manejo y conservación de la especie como recurso natural. En concreto, los estudios relativos a la monitorización hormonal son una herramienta básica para la investigación en biotecnología reproductiva moderna. No hay información sobre los cambios de progesterona durante la preñez de Dasyprocta sp. en comparación con otros histricomorfos. El objetivo de este estudio fue describir el perfil de la progesterona plasmática durante la preñez, y reportar el reinicio del ciclo ovárico después del parto. Para ello, se utilizaron 18 agoutis de rabo negro (Dasyprocta prymnolopha) nacidos en cautiverio. Fueron estudiadas una o más preñeces consecutivas. La copulación fue confirmada por la presencia de espermatozoides observados en examen colpocitológico. Las muestras de sangre se recogieron dos veces por semana, y las concentraciones de progesterona se determinaron en 10 individuos mediante radioinmunoensayo. Se observó el inicio de la actividad ovárica diaria por examen colpocitológico, comenzando en el día séptimo posparto. El período gestacional observado en este estudio fue de 104.04 días (SD= 1.31, rango entre 101-106 días, N= 26), y el intervalo entre los nacimientos fue 126.03 días (SD= 18.40, rango entre 109-184 días). El perfil plasmático de la progesterona durante el embarazo mostró un aumento progresivo de la 1ª a la 5ª semana. Los mayores niveles de progesterona durante este período (6.88 ng / mL, SD= 3.01) se detectaron en la quinta semana. Este valor fue similar (ANOVA de um factor, p > 0.05) al observado en las semanas cuatro y seis, pero fue estadísticamente diferente (ANOVA de um factor, p<0.05) en comparación con las otras semanas. Después de la sexta semana hubo una disminución progresiva en los niveles plasmáticos de progesterona. Los animales mostraron un estro posparto de 12.04 días (SD= 4.29, rango entre 7-24 días, N= 23). Se observó que el 80.95 % (N= 19) de cópulas durante este período fueron fértiles. Este trabajo contribuyó a la comprensión de los cambios dinámicos en los niveles de progesterona durante la preñez del agouti. Sin embargo, se necesitan más estudios para una mejor comprensión de otros cambios biológicos y endocrinos, y en la unidad materna y feto-placentaria del agouti.

Modelo experimental de endometrite em vacas inoculadas com Escherichia coli inativada por meio de infusão uterina / Endometritis experimental model in cows inoculated with inactivated Escherichia coli by uterine infusion

The aim of this study was to evaluate the endometrial inflammatory response of nine Zebu cows inoculated through uterine infusion with 30 mL of inactivated Escherichia coli suspension (1 x 109 UFC/mL) and nine with 30 mL of sterile phosphate buffered saline. Endometrial biopsies were performed before and after the inoculations during estrus, and ten days later in the diestrus phase. Neutrophilic infiltrates were observed in 88.8% of samples from the E. coli group in estrus phase and demonstrated different degrees of endometrial inflammation. This study characterizes a suitable model for studying endometritis in cattle.(AU)

Parâmetros reprodutivos e produtivos em vacas leiteiras de manejo free stall / Productive and reproductive parameters of dairy cows in free stall

Avaliou-se parâmetros reprodutivos e produtivos em vacas da raça Holandês-PB no pós-parto imediato, manejadas em free stall . Utilizou-se 51 vacas entre primíparas e pluríparas. Os valores obtidos foram: escore de condição corporal ao parto 3,47±0,4; intervalos do parto à primeira ovulação 5,89±3,4 semanas; ao primeiro serviço 112,5±57,0 dias; a taxa de gestação ao primeiro serviço foi 43,6% e no período experimental 76,4%, não sendo observada diferença para ordens de parto (P>0,05). A produção de leite acumulada à concepção, produção diária leite até a concepção e produção de leite ajustado para 305 foi respectivamente, 3.335,6±1.488,4; 25,8±5,4 e 7.424,0±1.877,8 litros. Conclui-se que no manejo de Free stall , a detecção de estro, foi o principal fator limitante para alcançar melhor eficiência reprodutiva.

The reproductive and productive parameters in postpartum of 51 primiparous and pluriparous Holstein cows housed in free stall were obtained. The values measured were: body condition score at parturition (3.47±0.4), interval from parturition to first ovulation (5.89±3.4 weeks), interval parturition at first service (112.5±57.0 days), first-service pregnancy rate (43.6%) and during the experimental period (76.4%). No difference was found between parturition order (P>0.05). The accumulated milk production until conception time, daily production until conception time, and adjusted 305-day milk production was respectively 3,335.6±1,488.4; 25.8±5.4 and 7,424.0±1,877.8 liters. In free stall of this study the estrus detection was the most limiting factor to improve the reproductive efficiency.

Performance of beef cows of different genetic groups in natural and cultivated pastures / Pastagens naturais e cultivadas no desempenho de vacas de corte de diferentes grupos genéticos

The objective was to assess the performance of 96 pregnant cows of the genetic groups (GG) Charolais (C), Nellore (N), ½ CN and ½ NC, subjected to the following treatments: kept exclusively in natural pastures (NP) throughout the experimental period; kept in cultivated pastures (CP) from July 15 to Setp 15 (CPNP) or from Sept 15 to Nov 15 (NPCP) and the remainder of the experimental period in NP. The weight at the end of the first grazing period (Sept 15) was higher for the CPNP cows than those of the NPCP and NP. The weight at the end of the second period (Nov 15) was 456, 428 and 392 kg respectively for NPCP, CPNP and NP. At calving, the heaviest cows were the CPNP, followed by the NPCP and the NP. At weaning, 90 days postpartum, the heaviest were the NPCP, followed by the CPNP and NP. Nelore cows were less heavy in all evaluations, followed by C, with the F1s' weight higher than the purebreds. The grazing sequences did not affect the percentages of the cows in estrus and pregnancy, but did influence the invervals between calving and first estrus postpartum (ICE). The GG influenced the rate of cows in estrus, pregnant and the ICE which was lower in the F1 (103 days), followed by the C (109 days) and had the largest interval N (119 days). The grazing sequences affect the average daily weight gain (ADG) of calves until weaning at 90 days of age. The GG of the calf affected the ADG at to 210 days.

Objetivou-se determinar o desempenho de 96 vacas prenhas dos grupos genéticos (GG) Charolês (C), Nelore (N), ½ CN e ½ NC, submetidos aos seguintes tratamentos: mantidas exclusivamente em pastagens naturais (PN) durante todo o período experimental; mantidas em pastagens cultivadas (PC) a partir de 15 de julho a 15 de setembro (PCPN) ou a partir de 15 de setembro a 15 de novembro (PNPC) e o restante do período experimental em PN. O peso no final do primeiro período de pastejo (15 de setembro) foi maior para as vacas PCPN que as do PNPC e PN. O peso no final do segundo período (15 de novembro) foi de 456, 428 e 392 kg, respectivamente, para PNPC, PCPN e PN. No parto as vacas da PCPN foram mais pesadas, seguidas pela PNPC e a PN. Ao desmame 90 dias de pós-parto o grupo mais pesado era de vacas da PNPC, seguido pelo PCPN e PN. Vacas N foram menos pesadas em todas as avaliações, seguidas pelas C, com o peso dos F1s maior do que os puros. As seqüências de pastagem não afetaram os percentuais de vacas em cio e prenhes, mas influenciou os intervalos entre partos e pós-parto ao primeiro cio (IPC). O GG influenciou a taxa de vacas em estro, prenhes e IPC que foi menor nas F1 (103 dias), seguidas das C (109 dias) e as N tiveram o maior intervalo (119 dias). As sequencias de pastejo influenciaram o ganho de peso médio diário (GMD) de bezerros até a idade do desmame aos 90 dias de idade. O GG do bezerro afetou a GMD até os 210 dias.