Review of the literature on corpus luteum insufficiency in women (2015–2020) and in domestic animals (1980–2020) / Revisión bibliográfica sobre la insuficiencia del cuerpo lúteo en la mujer (años 2015-2020) y en animales domésticos (años 1980-2020)

The corpus luteum (CL) is a transitory endocrine structure found in female mammals which secretes progesterone (P4), rendering the endometrium secretory and thus facilitating embryo implantation in the uterus. CL insufficiency (CLI) is defined as a condition in which CL P4 cannot maintain the endometrium and gestation, causing infertility and pregnancy loss. The present study aimed to compare specific aspects related to CLI in humans and domestic animals to identify its main aetiological differences and those related to treatment of the condition in different species.

El cuerpo lúteo (CL) es una estructura endocrina transitoria que se encuentra en las hembras de mamíferos y que secreta progesterona (P4), volviendo al endometrio secretor y facilitando así la implantación del embrión en el útero. La insuficiencia de CL se define como una condición en la que CL P4 no es capaz de mantener el endometrio y la gestación, provocando infertilidad y pérdida del embarazo. El presente estudio tuvo como objetivo comparar aspectos específicos relacionados con la insuficiencia del CL en humanos y animales domésticos con el fin de identificar sus principales diferencias etiológicas y las relacionadas con el tratamiento de dicha condición en distintas especies.

Pregnancy rates and luteal phase characteristics of bovine embryo recipients treated with flunixin meglumine / Taxas de prenhez e características da fase lútea de receptoras de embriões tratadas com flunixina meglumina em bovinos

The aim of this study was to evaluate the effects of flunixin meglumine administration on pregnancy rates and luteal phase characteristics in bovine embryo recipients at the moment of embryo transfer. In experiment 1, in vitro produced embryos were transferred to 184 females divided as control and treated group (recipients treated with 1.1mg/kg flunixin meglumine). In experiment 2, 22 females were divided as control group; group 2 (animals submitted to a reproductive tract manipulation similar to an embryo transfer on the 7th day after estrous); and group 3 (females submitted to a manipulation and treatment with 1.1mg/kg flunixin meglumine). In experiment 1 no difference was observed between control and treated groups (40.2% and 44.6%, respectively) for pregnancy rates. In experiment 2 no difference was observed on the length of luteal phase between groups, however, animals in group 2 presented lower plasma progesterone concentrations than the control group and group 3. Therefore, we concluded that although the administration of flunixin meglumine at the moment of embryo transfer inhibited the reduction plasma progesterone concentrations, it was not effective in increasing pregnancy rates of bovine recipients.(AU)

O objetivo deste estudo foi avaliar os efeitos da administração de flunixina meglumina sobre as taxas de prenhez e características da fase lútea da receptora no momento da transferência de embriões em bovinos. No experimento 1, embriões produzidos in vitro foram transferidos para 184 fêmeas, divididas em grupos controle e tratado (tratados com 1,1mg/kg de flunixina meglumina). No experimento 2, 22 fêmeas foram divididas em grupo controle (n=7); grupo 2 (n=8; animais submetidos à manipulação do trato reprodutivo semelhante à transferência de embriões no sétimo dia pós-cio); e grupo 3 (n=7; fêmeas submetidas à manipulação e ao tratamento com 1,1mg/kg de flunixina meglumina). No experimento 1, não foi observada diferença nos grupos controle e tratado (40,2% e 44,6%, respectivamente) para as taxas de prenhez. No experimento 2, não houve diferença na extensão da fase lútea entre os grupos, entretanto os animais do grupo 2 apresentaram concentrações plasmáticas de progesterona mais baixas que o grupo controle e o grupo 3. Portanto, conclui-se que a administração de flunixina meglumina no momento da transferência de embriões inibiu a redução das concentrações plasmáticas de progesterona, no entanto não foi eficaz para aumentar as taxas de prenhez de receptoras em bovinos.(AU)

Association between heart rate, heart rate variability, cortisol, glucose and electrolytes in healthy newborn calves / Associação entre frequência cardíaca, variabilidade da frequência cardíaca, cortisol, glicose e eletrólitos em bezerros recém-nascidos saudáveis

This study aims at evaluating the effects of electrolytes, glucose and cortisol levels over heart rate (HR) and heart rate variability (HRV) in healthy newborn calves. Seventeen healthy Holstein calves were evaluated during their first month of life, and the plasma concentrations of glucose, cortisol, calcium, magnesium, inorganic phosphorus, sodium and potassium were analyzed. HRV indexes were determined in the time and frequency domains through the analysis of neonatal electrocardiogram recordings. In the first day, low blood levels of phosphorus presented a strong correlation with the HR and the increased high-frequency components of HRV. The plasma concentrations of magnesium decreased significantly throughout the 35 days, revealing a positive association with a decreasing low-frequency components of HRV at day 28. There was a strong correlation between HR, HRV indexes, some plasma electrolytes, glucose and cortisol during the studied period. Variations in the concentrations and correlations observed may be attributed to the adaptive neonatal period in calves.(AU)

Este estudo teve como objetivo avaliar os efeitos dos níveis de eletrólitos, glicose e cortisol sobre a frequência cardíaca (FC) e a variabilidade da frequência cardíaca (VFC) em bezerros recém-nascidos e saudáveis. Dezessete bezerros da raça Holandesa foram avaliados durante o primeiro mês de vida e foram analisadas as concentrações plasmáticas de glicose, cortisol, cálcio, magnésio, fósforo inorgânico, sódio e potássio. Os índices VFC foram determinados em domínios de tempo e frequência por meio da análise de gravações do eletrocardiograma neonatal. No primeiro dia, baixos níveis sanguíneos de fósforo correlacionaram-se fortemente com FC e aumento dos componentes de alta frequência da VFC. As concentrações plasmáticas de magnésio diminuíram significativamente ao longo dos 35 dias, revelando correlação positiva com a diminuição dos componentes de baixa frequência da VFC no dia 28. Houve uma forte correlação entre FC, índices de VFC, eletrólitos plasmáticos, glicose e cortisol durante o período estudado. As variações nas concentrações e correlações observadas podem ser atribuídas ao período neonatal adaptativo em bezerros.(AU)

Morfometria e população de folículos pré-antrais de vacas Nelore vazias, gestantes e de fetos nos terços inicial, médio e final da gestação / Morphometry and population of preantral follicles of not pregnant Nelore cows, pregnant and fetus in the initial, medium and final third of pregnancy

The aim of this study was to describe population and morphological characteristics of preantral follicles of not pregnant cows, pregnant cows and fetus. Ten ovaries of non-pregnant Nelore cows, eighteen ovaries of pregnant cows and eighteen ovaries of fetus were used. For pregnant cows, six ovaries from each third (initial, middle and final) were evaluated, acquired from a slaughterhouse. For fetus, the same methodology and proportion of ovaries were used. Ovaries were washed, fixed and embedded in paraffin. They were then sectioned in longitudinal sections and stained by the Hematoxylin-Eosin method. Preantral follicles were classified according to morphology (primordial, primary and secondary) and degree of viability (intact and in initial, moderate and marked atresia). Descriptive and statistical analyzes were performed through KS300 image analysis program and Tukey's test. A greater proportion of primordial follicles were found in all categories. Secondary follicles were not observed in ovaries of fetus and cows in the initial third of pregnancy. All the ovary dimensions were higher in non-pregnant cows and in the final third of cows' pregnancy, and lower in final third of pregnancy fetus. It was concluded that follicle isolation was effective in describing population and morphological characteristics of preantral follicles of cows and fetus.(AU)

Intussuscepção uterina em uma cadela sem raça definida - relato de caso / Uterine intussusception in a crossbred female dog - case report

O presente relato descreve uma condição rara de intussuscepção uterina em uma cadela sem raça definida, quatro anos de idade, diagnosticada por meio de celiotomia exploratória e análise anatomopatológica. Foi realizada ovariossalpingo-histerectomia (OSH) como tratamento. Essa patologia geralmente requer manejo cirúrgico porque o diagnóstico inicial pode ser desafiador.(AU)

The present study describes a rare condition of uterine intussusception in a 4 year old crossbred female dog diagnosed by exploratory celiotomy and anatomopathological analysis. As treatment, a ovariohysterectomy (OH) was performed. This pathology usually requires surgical management because the initial diagnosis can be challenging.(AU)

The problem of resistance in Mycobacterium tuberculosis may be underestimated in Africa.

Background: The true burden of tuberculosis (TB) and particularly multidrug-resistant (MDR) TB in Sub-Saharan Africa has remained underestimated. Methods: We investigated drug susceptibility profile and genetic diversity of Mycobacterium tuberculosis isolates collected from confirmed tuberculosis patients in Ibadan, southwestern Nigeria. Results: We confirmed that from 74 randomly selected Mycobacterium tuberculosis isolates available for drug susceptibility testing in Ibadan, in 2011, 13.5% of them were MDR-TB. Conclusions: This figure is obviously above the national and World Health Organization figures.

Arterial blood flow is the main source of testicular heat in bulls and higher ambient temperatures significantly increase testicular blood flow.

Two experiments were done in bulls to determine: total testicular blood flow, testis oxygenation and heat, and effects of ambient temperature on testicular temperatures and blood flow. In Experiment 1, arterial blood flow to testes and testicular oxygenation and heat were determined in Angus bulls (n = 8). Blood temperature and hemoglobin O2 saturation were both greater (P < 0.0001) in the testicular artery than in the testicular vein (39.2 ±â€¯0.2 vs 36.9 ±â€¯0.4 °C and 95.3 ±â€¯0.7 vs 42.0 ±â€¯5.8%, respectively; mean ±â€¯SEM). Based on testicular blood flow of 12.4 ±â€¯1.1 mL/min and an arterial-venous temperature differential of 2.3 °C, blood contributed 28.3 ±â€¯5.1 cal/min of heat to the testis, whereas heat produced by testicular metabolism was estimated at 5.8 ±â€¯0.8 cal/min (based on O2 consumption of 1.2 ±â€¯0.2 mL/min). In Experiment 2, effects of three ambient temperatures (5, 15 and 35 °C) on testicular blood flow and temperatures were determined in 20 Angus bulls. At 35 versus 5 °C, there was greater testicular blood flow (8.2 ±â€¯0.9 versus 4.9 ±â€¯0.7 mL/min/100 g of testicular tissue, P < 0.05), and higher scrotal subcutaneous and intratesticular temperatures (P < 0.01). In conclusion, arterial blood flow was the main source of testicular heat, testes were close to hypoxia, and increased ambient temperature significantly increased scrotal subcutaneous and intratesticular temperatures, as well as testicular blood flow. These studies gave new insights into scrotal/testicular thermoregulation in bulls; they confirmed that testes are nearly hypoxic, but challenged the long-standing paradigm that testicular blood flow does not increase when testes become warmer.

Comparison of three different extenders on Murrah buffaloes (Bubalus bubalis) semen freezability.

The use of frozen semen for artificial insemination is the main approach utilised for the genetic improvement of most domesticated species. The advantages include lower transportation costs, continuous availability of semen, fewer occurrences of sexually transmitted diseases and the incorporation of desirable genes in a relatively short amount of time. Nevertheless, the use of frozen semen in buffalo herds remains limited due to the loss of sperm quality when buffalo semen is frozen. So, the goal of this study was to evaluate the pre- and post-cryopreservation quality of buffalo semen diluted in three distinct freezing media: Tris-egg yolk, Botu-bov® (BB) and ACP-111®. Thirty-two ejaculates from four bulls were analysed in terms of kinetics, morphology and sperm viability by epifluorescence microscope. Thawed samples were also evaluated for capacitation-like damage, DNA fragmentation and plasma and acrosomal membrane integrity using flow cytometry. The Tris-egg yolk and BB® extenders yielded better results than the ACP-111® extender for kinetics parameter (total motility, progressive motility and percentage of rapid cells). However, semen samples were similar for parameters evaluated by flow cytometry. Taken together, the data indicate that in comparison with Tris-egg yolk and BB extender, ACP-111® can also be used as an extender for buffalo semen cryopreservation.

Concentração sérica de progesterona, pH da vagina e morfometria corpórea de cervas gestantes (Cervus unicolor) em cativeiro / Serum concentration of progesterone, pH of the vagina and body morphometryof pregnant deer (Cervus unicolor)in captivity

The aim was to study pregnant cervus in captivity, to obtain body morphometric data, serum progesterone concentrations, and pH of the vagina. Females of cervus (Cervus unicolor), (n=8) between 2 and 3 years old were used in November during breeding season. After sedation, in one collection, the following was measured: body weight 54.50 ± 18.70kg, body length 1.21 ± 0.16m, height at withers 0.75 ± 0.08m, thoracic perimeter 0.84 ± 0.12m, and body mass index 97.32 ± 10.50kg / m2. After sedation, blood samples were collected to measure progesterone concentration by radioimmunoassay and the use of an indicator tape to obtain the pH of the vagina was performed eight times at four day intervals in the eight females, in a total of 64 samples for each exam. Data were analyzed, and significance was at 5%. There were no differences (P> 0.05) between measurements for serum progesterone concentrations and pH of the vagina. The correlations between body weight, progesterone, pH, and body mass index were not significant (P> 0.05). There was no significant oscillation of progesterone concentration and pH of the vagina in the pregnancy period studied.

Avaliação termográfica do desenvolvimento mamário de búfalas e sua regulação endócrina em distintos estágios fisiológicos / Thermographic evaluation of the mammary development of buffaloes and their endocrine regulation in different physiological stages

O conhecimento do desenvolvimento mamário de um rebanho leiteiro é fundamental, pois relaciona-se à eficiência produtiva. Objetivou-se avaliar a associação dos parâmetros térmicos mamários com concentrações hormonais de búfalas em distintos estágios fisiológicos. Foram utilizadas 24 búfalas mestiças Murrah, em quatro grupos (n= 6): grupo 1 (bezerras), grupo 2 (novilhas), grupo 3 (gestantes) e grupo 4 (lactantes). A cada 28 dias, durante 4 meses, realizaram-se exames de termografia digital por infravermelho para verificar temperatura superficial dos corpos mamários craniais (CMCr) e caudais (CMC), das cisternas craniais (CGMCr) e caudais (CGMC) e tetas craniais (TGMCr) e caudais (TGMC). Foi aferida temperatura retal (TR) e colhido sangue para mensuração das concentrações plasmáticas do fator semelhante a insulina tipo-I, insulina (INS), hormônio do crescimento (GH), progesterona (P4) e estradiol. Grupos 1 e 2 apresentaram correlação de TR com CGMCr. No grupo 3, TR correlacionou-se com TGMCr, TGMC e concentrações plasmáticas de P4. No grupo 4, houve correlação de TR com CGMC, TGMCr e concentrações plasmáticas de INS e GH, e de TGMC com concentrações plasmáticas de GH. Nos quatro grupos, CGMCr correlacionou-se com CMCr e TGMCr, semelhantemente ao observado na porção caudal. Variações térmicas mamárias refletiram alterações fisiológicas aguardadas nos períodos avaliados.(AU)

The knowledge of the mammary development of a dairy herd is key, since it is related to its productive efficiency. The objective of this study was to evaluate the association of mammary thermal parameters with hormonal concentrations of buffaloes at different physiological stages. Twenty-four Murrah crossbred buffaloes were used in four groups (n= 6): group 1 (calves), group 2 (heifers), group 3 (pregnant animals) and group 4 (lactating animals). Every 28 days, for 4 months, infrared digital thermography was performed to check the surface temperature of cranial (CrCM) and caudal (CCM) corpus mammae, cranial (CrC) and caudal (CC) cisterns and cranial (CrT) and caudal teats (CT). Rectal temperature (RT) was measured and blood was collected to measure plasma concentrations of insulin-like factor I, insulin (INS), growth hormone (GH), progesterone (P4) and estradiol. Groups 1 and 2 presented correlation of RT with CrC. In group 3, RT correlated with CrT, CT and plasma P4 concentrations. In group 4, there was correlation of RT with CC, CrT and plasma concentrations of INS and GH, and CT with plasma GH concentrations. In all four groups, CrC correlated with CrCM and CrT, similar to that observed in the caudal portion. The thermal changes in the mammary glands reflected the expected physiological changes in the evaluated periods.(AU)

Concentração sérica de progesterona, pH da vagina e morfometria corpórea de cervas gestantes (Cervus unicolor) em cativeiro / Serum concentration of progesterone, pH of the vagina and body morphometryof pregnant deer (Cervus unicolor)in captivity

The aim was to study pregnant cervus in captivity, to obtain body morphometric data, serum progesterone concentrations, and pH of the vagina. Females of cervus (Cervus unicolor), (n=8) between 2 and 3 years old were used in November during breeding season. After sedation, in one collection, the following was measured: body weight 54.50 ± 18.70kg, body length 1.21 ± 0.16m, height at withers 0.75 ± 0.08m, thoracic perimeter 0.84 ± 0.12m, and body mass index 97.32 ± 10.50kg / m2. After sedation, blood samples were collected to measure progesterone concentration by radioimmunoassay and the use of an indicator tape to obtain the pH of the vagina was performed eight times at four day intervals in the eight females, in a total of 64 samples for each exam. Data were analyzed, and significance was at 5%. There were no differences (P> 0.05) between measurements for serum progesterone concentrations and pH of the vagina. The correlations between body weight, progesterone, pH, and body mass index were not significant (P> 0.05). There was no significant oscillation of progesterone concentration and pH of the vagina in the pregnancy period studied.(AU)

Early and late analysis of postpartum stress in newborn foals / Análise do estresse no pós-parto imediato e tardio em potros neonatos

The aim of this study was to evaluate newborn foals stress in the first 48 hours of life. Heart rate (HR), heart rate variability (HRV) and serum cortisol concentrations, blood glucose, and lactate were determined in foals (n = 20, Paint Horse). Cortisol concentrations decreased significantly between four and 48 hours, with the highest concentration at 4 hours after birth. Positive correlations between cortisol and lactate occurred between 12 and 16 hours. And there was a negative correlation between cortisol and lactate 4 hours after birth. Among the values obtained for HR, there was significantly difference between the the value obtained at twelve hours of life moment and all the other moments measured, the highest values were at birth, 24 and 48 hours of life. Among HRV indexes, there were no statistical differences between the variables analysed. The cortisol, HR and HRV alterations were consistent to neonatal stress, but might be related to extrauterine environment adaptation associated to sympathoadrenal response, since those foals were healthy.(AU)

O objetivo deste estudo foi avaliar o estresse em potros neonatos nas primeiras 48 horas de vida. FC, VFC, concentrações de cortisol sérico, glicemia e lactatemia foram determinadas em potros (n = 20; Paint Horse). As concentrações de cortisol reduziram significativamente, entre quatro e 48 horas, sendo o maior valor observado às quatro horas após o nascimento. Correlações positivas entre cortisol e lactato ocorreram entre 12 e 16 horas de vida. E ocorreu correlação negativa entre cortisol e lactato às quatro horas de vida. Os valores de FC divergiram significativamente entre os momentos ao nascimento, quatro, oito, 16, 20, 24, 36 e 48 horas quanto comparados com as 12 horas de vida, sendo os maiores valores ao nascimento, às 24 e às 48 horas. Entre os índices de VFC, não foram observadas diferenças estatísticas para as variáveis analisadas. As alterações encontradas para cortisol, FC e VFC são condizentes com um quadro de estresse neonatal, mas podem estar relacionadas com o período de adaptação à vida extrauterina, associada a uma resposta simpatoadrenal, visto que os potros apresentavam-se saudáveis.(AU)

Cloprostenol administration in the first week postpartum reduces expression of oxytocin receptors in the endometrium in Holstein-Zebu cows / Administração de cloprostenol na primeira semana pós-parto pode reduzir a expressão de receptores de ocitocina no endométrio de vacas mestiças Holandês-Zebu

The present study investigated the hormonal profile and expression of prostaglandin F2α (PGF2α), oxytocin and estrogen receptors in uterine tissues of postpartum cows treated with cloprostenol. Twenty Holstein-Zebu crossbred cows were treated with saline solution (treatment CONT) or cloprostenol (treatment CLO), both administered two and five days postpartum. Blood samples were collected on days two, seven, 14, 21 and 28 postpartum for progesterone, PGF2α metabolite (PGFM) and estradiol determination, and endometrial biopsy was performed in order to quantify the expression of oxytocin receptor (OXTR), prostaglandin F receptor (PTGFR) and estrogen receptor 1 (ERS1) genes. In the CLO treatment, expression of OXTR was reduced (P<0.05) but no difference (P>0.05) between treatments was found for PTGFR and ERS1 expression. Estrogen concentrations increased progressively until day 14 (P<0.05) and the highest OXTR expression and lowest PTGFR expression were observed on day 14 (P<0.05) in both treatments. Serum PGFM concentrations were high throughout the experiment. In conclusion, cloprostenol administration at days two and five of postpartum seems to reduce OXTR expression in the endometrium in crossbred cows.(AU)

O presente estudo avaliou o perfil hormonal e a expressão gênica de receptores de prostaglandina F2α (PGF2α), ocitocina e estrógeno no endométrio de vacas pós-parto tratadas com cloprostenol. Vinte vacas mestiças Holandês-Zebu foram tratadas com solução salina (tratamento CONT, n = 10) ou cloprostenol (tratamento CLO, n = 10), ambos administrados dois e cinco dias após o parto. Amostras de sangue foram coletadas nos dias dois, sete, 14, 21 e 28 pós-parto para mensuração de progesterona, de metabólito de PGF2α (PGFM) e de estradiol, e foram obtidas biópsias endometriais para quantificar a expressão de PTGFR, OXTR e ESR1. No tratamento CLO, a expressão gênica de receptores de ocitocina foi menor (P<0,05). As concentrações de estrógeno aumentaram progressivamente até o dia 14 (P<0,05). A maior expressão de OXTR foi observada no dia 14 (P<0,05). A expressão de ESR1 foi semelhante entre os tratamentos (P>0,05). Os níveis de PGFM foram altos durante todo o estudo. Conclui-se que a administração de cloprostenol nos dias dois e cinco pós-parto parece diminuir a expressão de OXTR no endométrio em vacas mestiças.(AU)

Effect of selenium supplementation on semen characteristics of Brazil's ram.

The aim of this study was to investigate the effects of different concentrations of oral supplementation with selenium (Se) upon ram sperm parameters. Thirty rams managed in stall under intensive system were used and divided into five groups (six animals per group) as follows: control group (G1) mineral mixture supplementation without Se, group 2 (G2) mineral mixture supplemented with 5 mg/kg Se, group 3 (G3) supplemented with 10 mg/kg Se, group 4 (G4) supplemented with 15 mg/kg Se and group 5 (G5) supplemented with 20 mg/kg Se. For each group, there was an adjustment period of 14 days. The experimental period was 350 days. Every 56 days, the animals were weighed and semen samples were collected by electroejaculation. Semen analysis included volume, mass moviment, total motility, vigour, concentration and morphology. For plasmatic and acrosomal membrane integrity evaluation and mitochondrial membrane potential were used a combination of fluorescent probes. Differences between means values obtained by analysis of variance were verified by Tukey test with 5% probability. There was no statistical difference between treatment groups in relation to volume, mass moviment, total motility, vigour, concentration, plasma and acrosomal membrane integrity (p > .05). Sperm morphology was different between treatment groups, the G1 (0 mg of selenium) had the highest percentage of major defects (11.11 ± 1.11a ; p < .05). It was concluded that selenium decrease the percentage of sperm defects and did not directly influence on ram sperm volume, mass moviment, total motility, vigour, concentration and membrane integrity.

Follicular wave emergence in Santa Inês ewes subjected to long-term, progesterone-based estrous synchronization protocols at different times of the year.

This study was conducted to document the pattern of antral follicular wave emergence throughout the 14-day, progesterone (P4)-based estrous synchronization protocol in ewes that were maintained in subtropical conditions, during the period of increasing day lengths (ID), decreasing day lengths (DD), and the transitional period (TP). In addition, the influence of ovarian status (i.e., size of ovarian antral follicles and the presence of corpora lutea) at the outset of P4 treatment on ensuing ovarian follicular wave development was examined. Sexually mature Santa Inês ewes (n=70) were subjected to one of the two estrous synchronization protocols in the three seasons. On Day 0, the ewes received an i.m. injection of prostaglandin F2α and an intravaginal P4-releasing device that remained in place for 14days (G-1CIDR) or was replaced on Day 7 (G-2CIDR). Daily ultrasonography of ovaries was conducted from Days 0 to 15. Mean (±SEM) numbers of follicular waves per ewe were 3.7±0.1 and 3.6±0.1 for G-1CIDR and G-2CIDR (P>0.05). The number of emerging follicular waves was greater (P<0.05) during the ID period than during the TP and DD periods (4.0±0.1, 3.4±0.1 and 3.6±0.1, respectively). The presence of medium-sized antral follicles (4.0 to 5.75mm) in the absence of corpora lutea at the time of CIDR insertion tended to advance follicular wave emergence. Although the long-term P4 treatment was not originally designed to synchronize follicular waves, there was a distinctive pattern of follicular wave dynamics during the period of application of CIDRs that was affected mainly by the number of emerging follicular waves and ovarian status at CIDR insertion.

Integrity of the plasma membrane, the acrosomal membrane, and the mitochondrial membrane potential of sperm in Nelore bulls from puberty to sexual maturity / A integridade da membrana plasmática, da membrana acrossomal e o potencial da membrana mitocondrial de espermatozoides de touros Nelore da puberdade até à maturidade sexual

This study evaluated the plasma membrane integrity, acrosomal membrane integrity, and mitochondrial membrane potential of Nelore bull sperm from early puberty to early sexual maturity and their associations with sperm motility and vigor, the mass motility of the spermatozoa (wave motion), scrotal circumference, and testosterone. Sixty Nelore bulls aged 18 to 19 months were divided into four lots (n=15 bulls/lot) and evaluated over 280 days. Semen samples, collected every 56 days by electroejaculation, were evaluated soon after collection for motility, vigor and wave motion under an optical microscope. Sperm membrane integrity, acrosomal integrity, and mitochondrial activity were evaluated under a fluorescent microscope using probe association (FITC-PSA, PI, JC-1, H342). The sperm were classified into eight integrity categories depending on whether they exhibited intact or damaged membranes, an intact or damaged acrosomal membrane, and high or low mitochondrial potential. The results show that bulls have a low amount of sperm with intact membranes at puberty, and the sperm show low motility, vigor, and wave motion; however, in bulls at early sexual maturity, the integrity of the sperm membrane increased significantly. The rate of sperm membrane damage was negatively correlated with motility, vigor, wave motion, and testosterone in the bulls, and a positive correlation existed between sperm plasma membrane integrity and scrotal circumference. The integrity of the acrosomal membrane was not influenced by puberty. During puberty and into early sexual maturity, bulls show low sperm mitochondrial potential, but when bulls reached sexual maturity, high membrane integrity with high mitochondrial potential was evident.(AU)

Este estudo avaliou a integridade da membrana plasmática, da membrana acrossomal e o potencial da membrana mitocondrial de espermatozoides de touros da raça Nelore da puberdade até à maturidade sexual e suas correlações com motilidade, vigor, turbilhão dos espermatozoides, circunferência escrotal e testosterona. Sessenta touros da raça Nelore, com idade entre 18 e 19 meses, foram divididos em quatro lotes (n=15 touros / lote) e foram avaliados por 280 dias. Coletaram-se as amostras de sêmen a cada 56 dias por eletroejaculação e, logo após, foram determinados a motilidade, o vigor e o turbilhão dos espermatozoides por microscopia óptica. A integridade da membrana de esperma, da membrana acrosomal e da atividade mitocondrial foi avaliada por microscopia de fluorescência, utilizando-se associação das sondas (FITC-PSA, PI, JC-1, H342). Os espermatozoides foram classificados em oito categorias de integridade, dependendo se eles exibiram membranas plasmática e mitocondrial intactas ou danificadas e potencial mitocondrial elevado ou baixo. Os resultados mostram que os touros têm uma baixa quantidade de espermatozoides com membranas íntegras na puberdade, com baixa motilidade, vigor e turbilhão. No entanto, nos touros na maturidade sexual precoce, a integridade da membrana dos espermatozoides aumentou significativamente. A taxa de dano à membrana espermática foi negativamente correlacionada com a motilidade, o vigor, o movimento das ondas e a concentração de testosterona nos touros, e uma correlação positiva existiu entre a integridade da membrana plasmática e a circunferência escrotal. A integridade da membrana acrossomal não foi influenciada pela puberdade.(AU)

Influence of feeding differentiation on the age at onset of puberty in Brazilian Bergamasca dairy ewe lambs / Influência da diferenciação alimentar na idade à puberdade em cordeiras da raça Bergamácia Brasileira

The objective of the study was to evaluate body growth and age at onset of puberty on lambs fed two specific diets for low and high growth rates. A herd of 20 Brazilian Bergamasca lambs was divided in two groups (n= 10) and kept confined throughout the experimental period, two animals of the same treatment/pen. Two phases were established: Phase 1, from 90 days of age until the onset of puberty; and Phase 2, from puberty onset up to 1 year old. For Phase 1, two distinct diets were formulated, being: Treatment A, which was formulated to obtain an average daily gain of approximately 150g; and Treatment B, for an average daily gain of about 250g. In Phase 2, a balanced, equal diet was provided to both groups. Every 14 days, the animals were weighed and given average daily gain, average daily dry matter intake and body condition score. From the 5th month of age on, in each group, a vasectomized male was used to detect estrus, establishing age at puberty onset and estrus interval for each lamb. Blood samples were collected every 28 days to determine plasma growth hormone concentration. Treatment B lambs gained more weight and had higher body condition score (P<0.05) and there was no difference for age at puberty onset and plasma growth hormone levels (P>0.05) between treatments. It was found that both treatments showed satisfactory performances. Thus, treatment A may be indicated as a reasonable feeding system to achieve positive responses on confined ewe lambs during growth phase.

O objetivo do estudo foi avaliar o crescimento corporal e idade de início da puberdade em cordeiras sob duas dietas específicas para taxas de crescimento baixas e altas. Um rebanho de 20 cordeiras Bergamácia Brasileira foi dividido em dois grupos (n= 10) e mantido confinado em todo período experimental, sendo dispostos dois animais do mesmo tratamento/baia. Duas fases foram estabelecidas: Fase 1, a partir de 90 dias de idade até o início da puberdade, e Fase 2, a partir do início da puberdade até 1 ano de idade. Para a fase 1, duas dietas distintas foram formuladas, sendo: Tratamento A, formulada para obter um ganho de peso diário de aproximadamente 150g; e Tratamento B, para um ganho de peso médio diário de cerca de 250g. Na Fase 2, uma dieta equilibrada idêntica foi fornecida para ambos os grupos. A cada 14 dias, os animais foram pesados e calcularam-se o ganho médio diário, o consumo médio diário de matéria seca e escore de condição corporal. A partir do quinto mês de idade, em cada grupo, um macho vasectomizado foi usado para detectar estro, estabelecendo a idade de início da puberdade e estro para cada cordeira. As amostras de sangue foram coletadas a cada 28 dias para determinar a concentração plasmática de hormônio do crescimento. Cordeiras do tratamento B ganharam mais peso e tiveram maior escore de condição corporal (P<0,05), mas não houve diferença de idade para o início da puberdade e para os níveis plasmáticos de hormônio do crescimento (P>0,05). Verificou-se que os tratamentos A e B apresentaram desempenhos satisfatórios. Assim, o tratamento A pode ser indicado como um sistema de alimentação para alcançar respostas positivas em cordeiras submetidas ao confinamento durante a fase de crescimento.

Effects of season and ovarian status on the outcome of long-term progesterone-based estrus synchronization protocols and ovulatory follicle development in Santa Inês ewes under subtropical conditions.

This study set out to investigate the efficiency of long-term estrus synchronization protocols and ovulatory follicle dynamics in ultrasonographically monitored Santa Inês ewes during lengthening (LD; September-October) and shortening photoperiods (SD; April-May), and the transitional period (TP; January). In addition, the influence of ovarian status (e.g., size of antral follicles and/or presence of corpora lutea) at the outset of the estrus synchronization protocols on the ensuing development of ovulatory follicles was examined. Seventy sexually mature Santa Inês ewes were subjected to one of the two estrus synchronization regimens; on Day 0 (random day of the estrous cycle or anovulatory period), the ewes were fitted with an intravaginal progesterone (P4)-releasing (controlled intrauterine drug release [CIDR]) device, which was left in place for 14 days (G-1CIDR, n = 35) or replaced on Day 7 (G-2CIDR, n = 35), and received an intramuscular injection of 10 mg of PGF2α. The ewes allocated to the G-1CIDR group had mean serum P4 concentrations less than 2 ng/mL during the last 4 days of the synchronization protocol. There were no differences (P > 0.05) in mean ovulation rates between the two protocols tested nor among the ewes varying in ovarian status or studied at different times of the year, but ovulations occurred ∼ 12 hours later in the TP compared with the SD period (P < 0.05). Ovulatory follicles emerged earlier (P < 0.05) in the G-1CIDR group than in the G-2CIDR group (Day 8.3 ± 0.5 vs. 9.2 ± 0.4) and during LD (Day 7.1 ± 0.6) compared with the TP (Day 9.1 ± 0.6) and SD (Day 9.9 ± 0.5 of the protocol). In conclusion, the replacement of CIDR devices prevented the occurrence of lower-than-normal luteal phase levels of P4 at the end of the 14-day estrus synchronization protocol. However, although this procedure and seasonal influences altered certain growth characteristics of ovulatory follicles, there were no effects of these factors on the mean ovulation rate.

Plasma pgfm and progesterone concentrations, luteolysis moment and estrous cycle length in Nelore cows submitted to uterine biopsies / Concentrações plasmáticas de pgfm e progesterona, luteólise e comprimento do ciclo estral em vacas Nelore submetidas à coleta de fragmentos endometriais

In this study, endometrial samples were collected in 14 Nelore cows on days zero (ovulation), five, nine, thirteen and nineteen of the estrous cycle (biopsy group), and in 15 females these collections weren't performed (control group). Biopsies were done on the uterine horn endometrium contralateral to the ovary with corpus luteum. Blood samples were taken at -24, -16, -8, 0 +8, +16 and +24 hours in relation to progesterone drop (<1ng/mL, zero moment) and evaluated for 13, 14-dihydro-15-keto prostaglandin F2-alpha (PGFM) by radioimmunoassay (RIA). Plasma progesterone concentration was determined by RIA every 24 hours. Data were analyzed by ANOVA using the PROC GLM and MIXED of the SAS. The mean value for PGFM during the entire period evaluated was greater in the biopsy group. The mean concentration of PGFM at moment zero was not different between the groups; the mean concentration of PGFM was higher in the biopsy group before and after the drop in progesterone level. The maximum mean concentration observed was not different between the groups; however, the mean minimum concentration was different with high values in the biopsy group. Although the PGFM concentrations were higher in the biopsy group, the biopsy and control groups had similar length of estrous cycle showing that repeated endometrial biopsy on the side contralateral to the ovary with corpus luteum does not affect luteolysis and the length of the estrous cycle.

No presente estudo, foram coletadas amostras endometriais de 14 vacas Nelore nos dias zero (dia da ovulação), cinco, nove, 13 e 19 do ciclo estral (grupo controle), e em 15 fêmeas essas coletas não foram realizadas (grupo controle). As biópsias foram realizadas no corno uterino contralateral ao ovário contendo o corpo lúteo. Amostras plasmáticas foram coletadas nos momentos -24, -16, -8, 0 +8, +16 e +24 horas em relação à queda de progesterona (<1ng/mL, momento zero) e avaliadas quanto à concentração de 13, 14-di-hidro-15-ceto prostaglandina F2-alpha (PGFM) por radioimunoensaio (RIA). As concentrações plasmáticas de progesterona foram avaliadas a cada 24 horas também por RIA. Os dados foram analisados por ANOVA empregando-se PROC GLM e MIXED do SAS. O valor médio de PGFM durante todo o período avaliado foi maior no grupo biópsia. A concentração média de PGFM no momento zero não diferiu entre os grupos, e foi maior no grupo biópsia antes e após a queda de progesterona. A concentração máxima observada não foi diferente entre os grupos, porém a concentração mínima diferiu com maiores valores observados no grupo biópsia. Embora as concentrações de PGFM fossem maior no grupo biópsia, ambos os grupos apresentaram o mesmo comprimento do ciclo estral, demonstrando que a coleta repetitiva de biópsias endometriais no corno uterino contraletral ao ovário contendo o corpo lúteo não afeta a luteólise e o comprimento do ciclo estral.

Colour Doppler Ultrasonography as a Tool to Assess Luteal Function in Santa Inês Ewes.

The aim of this study was to evaluate luteal dynamics in the Santa Inês ewes using colour Doppler (CD) ultrasonography. Oestrus was synchronized in nulliparous females (n = 18), and subsequently, they were only teased (n = 6) or teased and mated (n = 12). Blood samples were collected daily for plasma progesterone (P4 ) concentrations. Ultrasonographic images of corpora lutea (CL) in CD mode were obtained for further analysis in its largest diameter. The CD mode allowed an early sequential monitoring of CL that was visualized by the first time 0.77 ± 0.62 days after ovulation, with luteal area 29.68 ± 13.21 mm(2) . During the luteogenesis, a progressive increase was observed, followed by a plateau of luteal area, vascularization area and plasma concentrations of P4 reaching maximum values in D11 (124.0 ± 38.0 mm(2) , 52.78 ± 24.08 mm(2) and 11.23 ± 4.89 ng/ml, respectively). In the luteolysis, the plasma concentrations of P4 decreased sharply, whereas luteal and vascularization area gradually. The vascularization area was positively correlated with plasma concentrations of P4 during the luteogenesis (r = 0.22) and luteolysis (r = 0.48). The luteal dynamics of Santa Inês ewes showed patterns similar to those observed in other sheep breeds studied. The CD ultrasonography has the potential to be used as a tool to assess luteal function in sheep.