The influence of lactation on insulin and glucose metabolism, lipid profile, and cytokines in pregnant mares.

Glucose metabolism adapts to gestation, resulting in progressive physiological insulin resistance and increased insulin secretion to maintain maternal euglycemia and glucose availability for the developing fetus. These changes can impact mare fertility and maternal and neonatal health. This is the first comparison of body condition, regional adiposity, insulin and glucose dynamics, lipid metabolism, and cytokine production between lactating and non-lactating mares before, during pregnancy, and early postpartum. Twelve pregnancies from 9 broodmares, five nonlactating (NL) and seven lactating (L), were used. Evaluations were performed on the day of ovulation, at 55, 110, 165, 220, 275, and 330 days of gestation (D55, D110, D165, D220, D275, D330) and 21 days postpartum (21pp). Mares in the L group had lower basal insulin and glucose at the beginning of pregnancy, smaller area under the curve of insulin and glucose, and greater insulin sensitivity and glucose tolerance. Resistin was higher in D110 and D165 than in D0, D275, 330 and 21pp, while leptin was higher in D55, and in D110, at D110 it was equal to D0, D220, and D275, but higher than at D330 and D21pp. As for the groups, L presented lower body condition score (BCS), crest neck score (CNS), rump fat thickness (RUM), basal insulin, glucose area under the curve (AUCg), MIRG and higher RISQI, adiponectin and tumor necrosis factor (TNFα). There was no effect over time in non-esterified fatty acids (NEFA) concentrations between the L mares; in the NL, D275 presented higher concentrations than those of D0, D55, and D110, which in turn were equal to the other time points; there were higher concentrations in NL mares than L in samples D165 and D275. In conclusion, a different metabolic profile during pregnancy was detected, and NL mares were closer to the metabolic threshold for the occurrence of metabolic syndrome during pregnancy. Understanding the impacts of these differences on mare's health and their offspring's future is fundamental as most of our recipient mares for embryo transfer are non-lactating. Therefore, we suggest that further studies be performed to evaluate lactation's influence on mares' metabolic parameters.

Growth hormone receptor contributes to the activation of STAT5 in the hypothalamus of pregnant mice.

Growth hormone (GH) receptor (GHR) signaling induces the phosphorylation of the signal transducer and activator of transcription 5 (pSTAT5) in the cells of several tissues including in the hypothalamus. During pregnancy, several STAT5-recruiting hormones (e.g., prolactin, GH and placental lactogens) are highly secreted. However, the precise contribution of GHR signaling to the surge of pSTAT5 immunoreactive neurons that occurs in the hypothalamus of pregnant mice is currently unknown. Thus, the objective of the present study was to determine whether GHR expression in neurons is required for inducing pSTAT5 expression in several hypothalamic nuclei during pregnancy. Initially, we demonstrated that late pregnant C57BL/6 mice (gestational day 14 to 18) exhibited increased pulsatile GH secretion compared to virgin females. Next, we confirmed that neuron-specific GHR ablation robustly reduces hypothalamic Ghr mRNA levels and prevents GH-induced pSTAT5 in the arcuate, paraventricular and ventromedial hypothalamic nuclei. Subsequently, the number of pSTAT5 immunoreactive cells was determined in the hypothalamus of late pregnant mice. Although neuron-specific GHR ablation did not affect the number of pSTAT5 immunoreactive cells in the paraventricular nucleus of the hypothalamus, reduced pSTAT5 expression was observed in the arcuate and ventromedial nuclei of pregnant neuron-specific GHR knockouts, compared to control pregnant mice. In summary, a subset of hypothalamic neurons requires GHR signaling to express pSTAT5 during pregnancy. These findings contribute to the understanding of the endocrine factors that affect the activation of transcription factors in the brain during pregnancy.

Biochemical markers for pregnancy in the spent culture medium of in vitro produced bovine embryos†.

The present study aimed to identify biomarkers to assess the quality of in vitro produced (IVP) bovine embryos in the culture media. IVP embryos on Day (D) 5 of development were transferred to individual drops, where they were maintained for the last 48 h of culture. Thereafter, the medium was collected and the embryos were transferred to the recipients. After pregnancy diagnosis, the media were grouped into the pregnant and nonpregnant groups. The metabolic profiles of the media were analyzed via electrospray ionization mass spectrometry, and the concentrations of pyruvate, lactate, and glutamate were assessed using fluorimetry. The spectrometric profile revealed that the media from embryos from the pregnant group presented a higher signal intensity compared to that of the nonpregnant group; the ions 156.13 Da [M + H]+, 444.33 Da [M + H]+, and 305.97 Da [M + H]+ were identified as biomarkers. Spent culture medium from expanded blastocysts (Bx) that established pregnancy had a greater concentration of pyruvate (p = 0.0174) and lesser concentration of lactate (p = 0.042) than spent culture medium from Bx that did not establish pregnancy. Moreover, pyruvate in the culture media of Bx can predict pregnancy with 90.9% sensitivity and 75% specificity. In conclusion, we identified markers in the culture media that helped in assessing the most viable IVP embryos with a greater potential to establish pregnancy.

Oxytocin-induced prostaglandin F2-alpha release is low in early bovine pregnancy but increases during the second month of pregnancy†.

Circulating prostaglandin F2α metabolite (PGFM) after an oxytocin challenge was evaluated throughout the first 2 months of pregnancy in lactating Holstein cows. On day 11, 18, and 25 after artificial insemination (AI), and on days 32, 39, 46, 53, and 60 of pregnancy, cows were challenged with 50 IU oxytocin, i.m. Blood was collected before (0 min), 30, 60, 90, and 120 min after oxytocin for plasma PGFM concentrations. Ultrasound evaluations were performed for pregnancy diagnosis on day 32-60 post-AI. Nonpregnant (NP) cows on day 18 were designated by a lack of interferon-stimulated genes in peripheral blood leukocytes and Pregnant (P) based on day 32 ultrasound. On day 11, P and NP were similar with low PGFM and no effect of oxytocin on PGFM. On day 18, oxytocin increased PGFM (3-fold) in NP with little change in P cows. Comparing only P cows from day 11 to 60, basal circulating PGFM increased as pregnancy progressed, with day 11 and 18, lower than all days from day 25 to 60 of pregnancy. Oxytocin-induced PGFM in P cows on day 25 was greater than P cows on day 18 (2.9-fold). However, oxytocin-induced PGFM was lower on day 25 compared to day 53 and 60, with intermediate values on day 32, 39, and 46 of pregnancy. Thus, the corpus luteum (CL) of early pregnancy (day 11, 18) is maintained by suppression of PGF, as reflected by suppressed PGFM in this study. However, during the second month of pregnancy, uterine PGF secretion was not suppressed since basal PGFM and oxytocin-induced PGFM secretion were elevated. Apparently, mechanisms other than suppression of oxytocin receptors maintain CL after day 25 of pregnancy.

Brain STAT5 Modulates Long-Term Metabolic and Epigenetic Changes Induced by Pregnancy and Lactation in Female Mice.

Several metabolic and behavioral adaptations that emerge during pregnancy remain present after weaning. Thus, reproductive experience causes long-lasting metabolic programming, particularly in the brain. However, the isolate effects of pregnancy or lactation and the molecular mechanisms involved in these long-term modifications are currently unknown. In the current study, we investigated the role of brain signal transducer and activator of transcription-5 (STAT5), a key transcription factor recruited by hormones highly secreted during gestation or lactation, for the long-term adaptations induced by reproductive experience. In control mice, pregnancy followed by lactation led to increased body adiposity and reduced ambulatory activity later in life. Additionally, pregnancy+lactation induced long-term epigenetic modifications in the brain: we observed upregulation in hypothalamic expression of histone deacetylases and reduced numbers of neurons with histone H3 acetylation in the paraventricular, arcuate, and ventromedial nuclei. Remarkably, brain-specific STAT5 ablation prevented all metabolic and epigenetic changes observed in reproductively experienced control female mice. Nonetheless, brain-specific STAT5 knockout (KO) mice that had the experience of pregnancy but did not lactate showed increased body weight and reduced energy expenditure later in life, whereas pregnancy KO and pregnancy+lactation KO mice exhibited improved insulin sensitivity compared with virgin KO mice. In summary, lactation is necessary for the long-lasting metabolic effects observed in reproductively experienced female mice. In addition, epigenetic mechanisms involving histone acetylation in neuronal populations related to energy balance regulation are possibly associated with these long-term consequences. Finally, our findings highlighted the key role played by brain STAT5 signaling for the chronic metabolic and epigenetic changes induced by pregnancy and lactation.

Transition period produces changes in blood and body composition in mares / Período de transição produz alterações na composição do sangue e do corpo em éguas

Clinical and metabolic evaluation is necessary for the monitoring of pregnant and lactating mares, as they reflect the health of the animal. The body condition of the mare is an indicator of reproductive efficiency. The study aimed to determine the possible variations in body and metabolic condition in Mangalarga Marchador mares during the transition period. Forty-eight mares distributed in two groups were used: Maintenance Group (MG), composed of non-pregnant and non-lactating mares, and Transition Group (TG), formed by pregnant mares and who after delivery became lactating. Analyzes were performed in the times T-60, T-30 and T-15 before delivery, first six hours (T0) after delivery and T15, T30 and T60 days after delivery. MG was evaluated only at one time (T-60). Body weight and fat-free mass differed (P<0.05) between the groups. The percentage of fat was lower in MG. Mares had a higher fat percentage in TG at T-60 and T-30 times. There was a difference (P<0.05) in the amount of cholesterol between MG and TG (T0, T15 and T30). Triglycerides were different between the groups. TG showed higher concentrations of non-esterified fatty acids (P<0.05). There was a higher amount of glucose in TG (delivery and lactation) when compared to mares in MG. Changes in body condition and metabolic constituents occurred in the animals resulting from physiological adaptations of the transition period. The energetic components are the most affected from the transition period, with intense fat mobilization to supply the body demands.(AU)

Avaliações clínicas e metabólicas são necessárias para o monitoramento de éguas gestantes e lactantes, pois refletem a saúde do animal. A condição corporal da égua pode ser um indicador da eficiência reprodutiva. O estudo objetivou determinar as possíveis variações na condição corporal e metabólica em éguas Mangalarga Marchador durante o período de transição. Foram utilizadas 48 éguas distribuídas em dois grupos: Grupo em Manutenção (GM) composto por éguas não gestantes e não lactantes; Grupo em Transição (GT) formado por éguas gestantes e que após o parto tornaram-se lactantes. As análises foram realizadas nos tempos T-60, T-30 e T-15 antes do parto, primeiras seis horas (T0) após o parto e T15, T30 e T60 dias após o parto. O GM foi avaliado apenas uma vez (T-60). O peso corporal e a massa livre de gordura diferiram (P<0,05) entre os grupos. O percentual de gordura foi menor em GM. As éguas apresentaram maior porcentagem de gordura no GT no T-60 e no T-30. Houve diferença (P<0,05) na quantidade de colesterol entre GM e GT (T0, T15 e T30). Triglicérides foram diferentes entre os grupos. GT apresentou maiores concentrações de ácidos graxos não esterificados (P<0,05). Houve maior quantidade de glicose no GT (parto e lactação) quando comparada às éguas no GM. Mudanças na condição corporal e nos constituintes metabólicos ocorreram nos animais resultantes de adaptações fisiológicas do período de transição. Os componentes energéticos são os mais afetados neste período, existindo intensa mobilização de gordura para suprir demandas corporais.(AU)

Transition period produces changes in blood and body composition in mares / Período de transição produz alterações na composição do sangue e do corpo em éguas

Clinical and metabolic evaluation is necessary for the monitoring of pregnant and lactating mares, as they reflect the health of the animal. The body condition of the mare is an indicator of reproductive efficiency. The study aimed to determine the possible variations in body and metabolic condition in Mangalarga Marchador mares during the transition period. Forty-eight mares distributed in two groups were used: Maintenance Group (MG), composed of non-pregnant and non-lactating mares, and Transition Group (TG), formed by pregnant mares and who after delivery became lactating. Analyzes were performed in the times T-60, T-30 and T-15 before delivery, first six hours (T0) after delivery and T15, T30 and T60 days after delivery. MG was evaluated only at one time (T-60). Body weight and fat-free mass differed (P<0.05) between the groups. The percentage of fat was lower in MG. Mares had a higher fat percentage in TG at T-60 and T-30 times. There was a difference (P<0.05) in the amount of cholesterol between MG and TG (T0, T15 and T30). Triglycerides were different between the groups. TG showed higher concentrations of non-esterified fatty acids (P<0.05). There was a higher amount of glucose in TG (delivery and lactation) when compared to mares in MG. Changes in body condition and metabolic constituents occurred in the animals resulting from physiological adaptations of the transition period. The energetic components are the most affected from the transition period, with intense fat mobilization to supply the body demands.(AU)

Avaliações clínicas e metabólicas são necessárias para o monitoramento de éguas gestantes e lactantes, pois refletem a saúde do animal. A condição corporal da égua pode ser um indicador da eficiência reprodutiva. O estudo objetivou determinar as possíveis variações na condição corporal e metabólica em éguas Mangalarga Marchador durante o período de transição. Foram utilizadas 48 éguas distribuídas em dois grupos: Grupo em Manutenção (GM) composto por éguas não gestantes e não lactantes; Grupo em Transição (GT) formado por éguas gestantes e que após o parto tornaram-se lactantes. As análises foram realizadas nos tempos T-60, T-30 e T-15 antes do parto, primeiras seis horas (T0) após o parto e T15, T30 e T60 dias após o parto. O GM foi avaliado apenas uma vez (T-60). O peso corporal e a massa livre de gordura diferiram (P<0,05) entre os grupos. O percentual de gordura foi menor em GM. As éguas apresentaram maior porcentagem de gordura no GT no T-60 e no T-30. Houve diferença (P<0,05) na quantidade de colesterol entre GM e GT (T0, T15 e T30). Triglicérides foram diferentes entre os grupos. GT apresentou maiores concentrações de ácidos graxos não esterificados (P<0,05). Houve maior quantidade de glicose no GT (parto e lactação) quando comparada às éguas no GM. Mudanças na condição corporal e nos constituintes metabólicos ocorreram nos animais resultantes de adaptações fisiológicas do período de transição. Os componentes energéticos são os mais afetados neste período, existindo intensa mobilização de gordura para suprir demandas corporais.(AU)

Central growth hormone action regulates metabolism during pregnancy.

The maternal organism undergoes numerous metabolic adaptations to become prepared for the demands associated with the coming offspring. These metabolic adaptations involve changes induced by several hormones that act at multiple levels, ultimately influencing energy and glucose homeostasis during pregnancy and lactation. Previous studies have shown that central growth hormone (GH) action modulates glucose and energy homeostasis. However, whether central GH action regulates metabolism during pregnancy and lactation is still unknown. In the present study, we generated mice carrying ablation of GH receptor (GHR) in agouti-related protein (AgRP)-expressing neurons, in leptin receptor (LepR)-expressing cells or in the entire brain to investigate the role played by central GH action during pregnancy and lactation. AgRP-specific GHR ablation led to minor metabolic changes during pregnancy and lactation. However, while brain-specific GHR ablation reduced food intake and body adiposity during gestation, LepR GHR knockout (KO) mice exhibited increased leptin responsiveness in the ventromedial nucleus of the hypothalamus during late pregnancy, although their offspring showed reduced growth rate. Additionally, both Brain GHR KO and LepR GHR KO mice had lower glucose tolerance and glucose-stimulated insulin secretion during pregnancy, despite presenting increased insulin sensitivity, compared with control pregnant animals. Our findings revealed that during pregnancy central GH action regulates food intake, fat retention, as well as the sensitivity to insulin and leptin in a cell-specific manner. Together, the results suggest that GH acts in concert with other "gestational hormones" to prepare the maternal organism for the metabolic demands of the offspring.

Atividade reprodutiva em éguas quarto de milha durante o período de transição de primavera na região da Zona da Mata, Rondônia / Evaluation of the ciclicity of mares in the regions of Mata Zone, Rondonia State

O objetivo do presente estudo foi avaliar a ocorrência da ciclicidade, o diâmetro do folículo dominante e do grau de edema uterino de éguas criadas na zona da mata do Estado de Rondônia, durante o período de transição da estacionalidade reprodutiva. Para este propósito, durante os meses de agosto e setembro (transição de primavera), éguas da raça Quarto de Milha (n = 46), hígidas, criadas a campo ou estabuladas, com idades variando de 2 a 12 anos foram submetidas a dois exames ginecológicos com intervalo de 14 dias, a fim de se determinar e/ou monitorar a presença de corpo lúteo, o diâmetro do folículo dominante e o grau de edema uterino. Empregando um modelo de regressão logística, o efeito do sistema de criação (a campo ou estabuladas) e da faixa etária ( 5, de 6 a 9 e 10 anos) foram avaliados sobre a ocorrência da ciclicidade, bem como sobre o diâmetro do folículo dominante e o grau de edema uterino por meio do modelo linear generalizado misto. Uma maior proporção de éguas (p = 0,001) foi considerada acíclica em relação às cíclicas [68,9% (31/45) vs. 31,1% (14/45), respectivamente]. Dentre as éguas acíclicas, houve uma semelhança (p = 0,127) na proporção daquelas com folículo dominante ou com folículos pequenos. O sistema de criação não influenciou (p > 0,05) a ocorrência da ciclicidade, o diâmetro do folículo dominante e o grau de edema uterino. A faixa etária (≤ 5, de 6 a 9 e ≥ 10 anos) determinou influencia (p < 0,05) na ocorrência da ciclicidade [28,6 b; 18,2b e 66,7% a; respectivamente] e no grau de edema uterino (1,0 ± 0,1 b; 2,0 ± 0,1 a e 2,0 ± 0,2 a; respectivamente). Conclui-se que a maioria das éguas criadas na região da zona da mata rondoniense apresentam-se acíclicas no período de transição de primavera. No entanto, a ocorrência da ciclicidade e o grau de edema uterino demonstraram ser influenciados pela faixa etária das éguas avaliadas.

The objective of this study was to evaluate the occurrence of cyclicity, the diameter of the dominant follicle and the degree of uterine edema in mares from forest area of the Rondonia State, during the transitional period of reproductive season. For this purpose, during the months of August and September (spring transition), healthy mares, Quarter Horse breed (N = 46), field or housed and aged 2 to 12 years were submitted to two examinations gynecological examination with a 14-day interval. The exams were performed to determine and / or monitor the presence of corpus luteum, the diameter of the dominant follicle and the degree of uterine edema. Using a logistic regression model, the effect of the breeding system (field or stabled) and age group (≤ 5, from 6 to 9 and ≥ 10 years) were evaluated on the occurrence of cyclicity as well as on the diameter of the dominant follicle and the degree of uterine edema by generalized linear mixed model. A higher proportion of mares (P = 0.001) was considered acyclical in relation to the cyclical (68.9% (31/45) vs. 31.1% (14/45), respectively]. Among the acyclic mares, there was a similarity (P = 0.127) in proportion to those with dominant follicle or with small follicles. The breeding system did not influence (P > 0.05) the occurrence of cyclicity, the diameter of the dominant follicle and the degree of uterine edema. The age group (≤ 5, from 6 to 9 and ≥ 10 years) determined influence (P < 0.05) on the occurrence of cyclicity (28.6 b; 18.2 b and 66.7% a; respectively) and in the degree of uterine edema (1.0 ± 0.1 b, 2.0 ± 0.1 a and 2.0 ± 0.2 a, respectively). It is concluded that the majority of the mares created in the forest zone of Rondônia region are acyclical in the period of transition of spring. However, the occurrence of cyclicity and the degree of uterine edema were influenced by the age range of the mares evaluated.

Atividade reprodutiva em éguas quarto de milha durante o período de transição de primavera na região da Zona da Mata, Rondônia / Evaluation of the ciclicity of mares in the regions of Mata Zone, Rondonia State

O objetivo do presente estudo foi avaliar a ocorrência da ciclicidade, o diâmetro do folículo dominante e do grau de edema uterino de éguas criadas na zona da mata do Estado de Rondônia, durante o período de transição da estacionalidade reprodutiva. Para este propósito, durante os meses de agosto e setembro (transição de primavera), éguas da raça Quarto de Milha (n = 46), hígidas, criadas a campo ou estabuladas, com idades variando de 2 a 12 anos foram submetidas a dois exames ginecológicos com intervalo de 14 dias, a fim de se determinar e/ou monitorar a presença de corpo lúteo, o diâmetro do folículo dominante e o grau de edema uterino. Empregando um modelo de regressão logística, o efeito do sistema de criação (a campo ou estabuladas) e da faixa etária ( 5, de 6 a 9 e 10 anos) foram avaliados sobre a ocorrência da ciclicidade, bem como sobre o diâmetro do folículo dominante e o grau de edema uterino por meio do modelo linear generalizado misto. Uma maior proporção de éguas (p = 0,001) foi considerada acíclica em relação às cíclicas [68,9% (31/45) vs. 31,1% (14/45), respectivamente]. Dentre as éguas acíclicas, houve uma semelhança (p = 0,127) na proporção daquelas com folículo dominante ou com folículos pequenos. O sistema de criação não influenciou (p > 0,05) a ocorrência da ciclicidade, o diâmetro do folículo dominante e o grau de edema uterino. A faixa etária (≤ 5, de 6 a 9 e ≥ 10 anos) determinou influencia (p < 0,05) na ocorrência da ciclicidade [28,6 b; 18,2b e 66,7% a; respectivamente] e no grau de edema uterino (1,0 ± 0,1 b; 2,0 ± 0,1 a e 2,0 ± 0,2 a; respectivamente). Conclui-se que a maioria das éguas criadas na região da zona da mata rondoniense apresentam-se acíclicas no período de transição de primavera. No entanto, a ocorrência da ciclicidade e o grau de edema uterino demonstraram ser influenciados pela faixa etária das éguas avaliadas.(AU)

The objective of this study was to evaluate the occurrence of cyclicity, the diameter of the dominant follicle and the degree of uterine edema in mares from forest area of the Rondonia State, during the transitional period of reproductive season. For this purpose, during the months of August and September (spring transition), healthy mares, Quarter Horse breed (N = 46), field or housed and aged 2 to 12 years were submitted to two examinations gynecological examination with a 14-day interval. The exams were performed to determine and / or monitor the presence of corpus luteum, the diameter of the dominant follicle and the degree of uterine edema. Using a logistic regression model, the effect of the breeding system (field or stabled) and age group (≤ 5, from 6 to 9 and ≥ 10 years) were evaluated on the occurrence of cyclicity as well as on the diameter of the dominant follicle and the degree of uterine edema by generalized linear mixed model. A higher proportion of mares (P = 0.001) was considered acyclical in relation to the cyclical (68.9% (31/45) vs. 31.1% (14/45), respectively]. Among the acyclic mares, there was a similarity (P = 0.127) in proportion to those with dominant follicle or with small follicles. The breeding system did not influence (P > 0.05) the occurrence of cyclicity, the diameter of the dominant follicle and the degree of uterine edema. The age group (≤ 5, from 6 to 9 and ≥ 10 years) determined influence (P < 0.05) on the occurrence of cyclicity (28.6 b; 18.2 b and 66.7% a; respectively) and in the degree of uterine edema (1.0 ± 0.1 b, 2.0 ± 0.1 a and 2.0 ± 0.2 a, respectively). It is concluded that the majority of the mares created in the forest zone of Rondônia region are acyclical in the period of transition of spring. However, the occurrence of cyclicity and the degree of uterine edema were influenced by the age range of the mares evaluated.(AU)

Energetic metabolism in fasting sheep: regularization of metabolic profile by treatment with oral glucose, with prior handling of gastric groove

The objective of this research was to evaluate a possible corrective measure against negative metabolic states, as occurs in the advanced stage of gestation in ewes, and that sometimes produces a disease called pregnancy toxaemia. In the present research, we found that the joint administration of i.v. lysine-vasopressin (0.08 IU/kg body weight, BW) and an oral glucose solution (50 g) produces an increase in blood glucose, which persists for some time (up to 6 h); therefore, it could be used in the treatment of pregnancy toxaemia. This therapy is based on the fact that lysine-vasopressin induces gastric groove closure in adult ruminants, enabling orally administered glucose to reach the abomasum directly, from where it rapidly passes into the intestine and is immediately absorbed. We can say that the tested treatment causes a significant increase in blood glucose in ewes affected by toxaemia caused by fasting, which, although less marked than conventional therapy with intravenous drip glucose, remains longer, regularizing other parameters indicative of energy metabolism in fasting ewes.(AU)

Biomarcadores fisiológicos em éguas no período de transição: o que eles expressam / Physiological biomarkers in mares in the transition period: what they express / Biomarcadores fisiológicos en yeguas en el período de transición: lo que expresan

Avaliações clínicas, hematológicas e bioquímicas são usadas em todas as classes de animais com a mesma finalidade, avaliação da saúde animal, além de monitorar e auxiliar no diagnóstico de doenças ou síndromes. As adaptações metabólicas que ocorrem durante o período de transição nas éguas são complexas e generalizadas, e estão associadas a um estado metabólico alterado quando comparado ao período não gestacional. Durante a prenhez as necessidades nutricionais aumentam com a proximidade do parto, tornando-se mais acentuada após o parto devido a lactação. Diferentes estudos são realizados em éguas gestantes e lactantes avaliando as variações hormonais, contudo, a análise dos perfis hematológico e metabólico no período de transição faz-se necessário para que se possa identificar possíveis problemas na saúde do animal. O presente estudo buscou descrever as principais alterações clínicas, hematológicas e bioquímicas em éguas no período de transição.

Clinical, hematological, and biochemical assessments are used in all classes of animals for the same purpose, animal health assessment, and to monitor and assist in the diagnosis of diseases or syndromes. Metabolic adaptations that occur during the transitional period in mares are complex and generalized, and are associated with an altered metabolic state when compared to the non-gestational period. During pregnancy the nutritional needs increase with the proximity of the childbirth, becoming more pronounced after childbirth due to lactation. Different studies are carried out in pregnant and lactating mares evaluating the hormonal variations, however, the analysis of the hematological and metabolic profiles in the transition period is necessary in order to identify possible problems in the health of the animal. The present study aimed to describe the main clinical, hematological and biochemical alterations in mares in the transition period.

Las evaluaciones clínicas, hematológicas y bioquímicas se utilizan en todas las clases de animales con la misma finalidad, evaluación de la salud animal, además de monitorear y auxiliar en el diagnóstico de enfermedades o síndromes. Las adaptaciones metabólicas que ocurren durante el período de transición en las yeguas son complejas y generalizadas, y están asociadas a un estado metabólico alterado cuando comparado al período no gestacional. Durante la preñez las necesidades nutricionales aumentan con la proximidad del parto, haciéndo se más acentuada después del parto debido a la lactancia. Diferentes estudios se realizan en yeguas gestantes y lactantes evaluando las variaciones hormonales, sin embargo, el análisis de los perfiles hematológico y metabólico en el período de transición se hace necesario para que se puedan identificar posibles problemas en la salud del animal. El presente estudio buscó describir las principales alteraciones clínicas, hematológicas y bioquímicas en yeguas en el período de transición.

Biomarcadores fisiológicos em éguas no período de transição: o que eles expressam / Physiological biomarkers in mares in the transition period: what they express / Biomarcadores fisiológicos en yeguas en el período de transición: lo que expresan

Avaliações clínicas, hematológicas e bioquímicas são usadas em todas as classes de animais com a mesma finalidade, avaliação da saúde animal, além de monitorar e auxiliar no diagnóstico de doenças ou síndromes. As adaptações metabólicas que ocorrem durante o período de transição nas éguas são complexas e generalizadas, e estão associadas a um estado metabólico alterado quando comparado ao período não gestacional. Durante a prenhez as necessidades nutricionais aumentam com a proximidade do parto, tornando-se mais acentuada após o parto devido a lactação. Diferentes estudos são realizados em éguas gestantes e lactantes avaliando as variações hormonais, contudo, a análise dos perfis hematológico e metabólico no período de transição faz-se necessário para que se possa identificar possíveis problemas na saúde do animal. O presente estudo buscou descrever as principais alterações clínicas, hematológicas e bioquímicas em éguas no período de transição.(AU)

Clinical, hematological, and biochemical assessments are used in all classes of animals for the same purpose, animal health assessment, and to monitor and assist in the diagnosis of diseases or syndromes. Metabolic adaptations that occur during the transitional period in mares are complex and generalized, and are associated with an altered metabolic state when compared to the non-gestational period. During pregnancy the nutritional needs increase with the proximity of the childbirth, becoming more pronounced after childbirth due to lactation. Different studies are carried out in pregnant and lactating mares evaluating the hormonal variations, however, the analysis of the hematological and metabolic profiles in the transition period is necessary in order to identify possible problems in the health of the animal. The present study aimed to describe the main clinical, hematological and biochemical alterations in mares in the transition period.(AU)

Las evaluaciones clínicas, hematológicas y bioquímicas se utilizan en todas las clases de animales con la misma finalidad, evaluación de la salud animal, además de monitorear y auxiliar en el diagnóstico de enfermedades o síndromes. Las adaptaciones metabólicas que ocurren durante el período de transición en las yeguas son complejas y generalizadas, y están asociadas a un estado metabólico alterado cuando comparado al período no gestacional. Durante la preñez las necesidades nutricionales aumentan con la proximidad del parto, haciéndo se más acentuada después del parto debido a la lactancia. Diferentes estudios se realizan en yeguas gestantes y lactantes evaluando las variaciones hormonales, sin embargo, el análisis de los perfiles hematológico y metabólico en el período de transición se hace necesario para que se puedan identificar posibles problemas en la salud del animal. El presente estudio buscó describir las principales alteraciones clínicas, hematológicas y bioquímicas en yeguas en el período de transición.(AU)

Physiological changes in the adenosine deaminase activity, antioxidant and inflammatory parameters in pregnant cows and at post-partum.

The aim of this study was to evaluate the behaviour of adenosine deaminase (ADA) activity, as well as its participation in the immunomodulation of pregnant cows. Thus, sixteen cows were divided into two groups (A and B): the group A was composed by cows not pregnant (n = 8), while the group B was composed by pregnant cows (n = 8). Serum levels of interleukin-10 (IL-10), IL-6, tumour necrosis factor alpha (TNF-α), reactive oxygen species (ROS) and C-reactive protein (CRP), as well as ADA and glutathione S-transferase (GST) activities, were measured on five sampling times (3, 5, 7 and 8 months of gestation, and soon after calving). Serum ADA activity was similar throughout the experiment in the cows belonging to the group A, but its activity increased during the experiment in cows from the group B, that is it was lower in the third and fifth months of pregnancy, and higher on months 7, 8 and after calving when compared to the group A. TNF-α and IL-6 serum levels were lower in pregnant cows compared to non-pregnant animals; however, they significantly increased after calving. Serum levels of IL-10 increased after 8 months of gestation, but it reduced after calving when compared to the group A, while CRP increased on month 8 of gestation and after calving compared to the group A. Pregnant cows showed lower serum ROS levels on months 3, 5 and 7 of gestation, and higher levels at the post-partum. Serum GST activity was higher on month 5 of gestation in pregnant cows, but it was lower on months 7, 8 and in the post-partum compared to the group A. Based on these evidence, we concluded that ADA activity and the others mediators or inflammatory modulators have important role in the maintenance of cow's gestation due to their immunomodulatory effects.

Role of sex hormones in gastrointestinal motility in pregnant and non-pregnant rats.

AIM: To correlate gastric contractility, gastrointestinal transit, and hormone levels in non-pregnant (estrous cycle) and pregnant rats using noninvasive techniques. METHODS: Female rats (n = 23) were randomly divided into (1) non-pregnant, (contractility, n = 6; transit, n = 6); and (2) pregnant (contractility, n = 5; transit, n = 6). In each estrous cycle phase or at 0, 7, 14, and 20 d after the confirmation of pregnancy, gastrointestinal transit was recorded by AC biosusceptometry (ACB), and gastric contractility was recorded by ACB and electromyography. After each recording, blood samples were obtained for progesterone and estradiol determination. RESULTS: In the estrous cycle, despite fluctuations of sex hormone levels, no significant changes in gastrointestinal motility were observed. Days 7 and 14 of pregnancy were characterized by significant changes in the frequency of contractions (3.90 ± 0.42 cpm and 3.60 ± 0.36 cpm vs 4.33 ± 0.25 cpm) and gastric emptying (168 ± 17 min and 165 ± 15 min vs 113 ± 15 min) compared with day 0. On these same days, progesterone levels significantly increased compared with control (54.23 ± 15.14 ng/mL and 129.96 ± 30.52 ng/mL vs 13.25 ± 6.31 ng/mL). On day 14, we observed the highest level of progesterone and the lowest level of estradiol compared with day 0 (44.3 ± 15.18 pg/mL vs 24.96 ± 5.96 pg/mL). CONCLUSION: Gastrointestinal motility was unaffected by the estrous cycle. In our data, high progesterone and low estradiol levels can be associated with decreased contraction frequency and slow gastric emptying.

Day-restricted feeding during pregnancy and lactation programs glucose intolerance and impaired insulin secretion in male rat offspring.

AIM: The maternal environment during pregnancy and lactation plays a determining role in programming energy metabolism in offspring. Among a myriad of maternal factors, disruptions in the light/dark cycle during pregnancy can program glucose intolerance in offspring. Out-of-phase feeding has recently been reported to influence metabolism in adult humans and rodents; however, it is not known whether this environmental factor impacts offspring metabolism when applied during pregnancy and lactation. This study aims to determine whether maternal day-restricted feeding (DF) influences energy metabolism in offspring. METHODS: Pregnant and lactating Wistar rats were subjected to ad libitum (AL) or DF during pregnancy and lactation. The offspring born to the AL and DF dams were intra- and interfostered, which resulted in 4 group types. RESULTS: The male offspring born to and breastfed by the DF dams (DF/DF off) were glucose intolerant, but without parallel insulin resistance as adults. Experiments with isolated pancreatic islets demonstrated that the male DF/DF off rats had reduced insulin secretion with no parallel disruption in calcium handling. However, this reduction in insulin secretion was accompanied by increased miRNA-29a and miRNA34a expression and decreased syntaxin 1a protein levels. CONCLUSION: We conclude that out-of-phase feeding during pregnancy and lactation can lead to glucose intolerance in male offspring, which is caused by a disruption in insulin secretion capacity. This metabolic programming is possibly caused by mechanisms dependent on miRNA modulation of syntaxin 1a.

Efeitos do manejo no período pré-parto sobre o crescimento e a saúde dos bezerros

O período pré-parto ou período seco da vaca leiteira é importante não apenas para o desenvolvimento fetal,mas também para a intensa involução e regeneração da glândula mamária, os quais são fatores que determinam a produção leiteira da vaca na próxima lactação (Capuco et al., 1997; Sorensenet al., 2006). Além disso, o período de transição é caracterizado por disfunção imune e desafios metabólicos,o que leva ao uso de diferentes estratégias nutricionais e de manejo durante o pré-parto,visando melhorar o desempenho da vaca no período pós-parto (revisadopor Mallard et al.,1998; Drackley, 1999; bigstockphoto. com O período de transição é caracterizado por disfunção imune e desafios metabólicos,o que leva ao uso de diferentes estratégias nutricionais e de manejo durante o pré-parto,visando melhorar o desempenho da vaca no período pós-parto. 10 Cadernos Técnicos de Veterinária e Zootecnia, nº 81 - junho de 2016Tao e Dahl, 2013).

Consequences of eight consecutive applications of equine chorionic gonadotropin on ovarian follicle development and ovulation in bos indicus cows / Consequências do uso consecutivo de oito doses de gonadotrofina coriônica equina no desenvolvimento folicular e ovulação de vacas bos indicus

The equine chorionic gonadotropin (eCG) is a glycoprotein produced in mare endometrial calices. In bovine, it is used in estrus synchronization protocols. However, studies have shown that it is potentially immunogenic and its effect can decrease after repetitive use. This study aimed to evaluate antral follicle dynamics, corpus luteum (CL) and ovulation rate in bos indicus cows submitted to an estrus synchronization protocol in association with eCG for eight times consecutively. Ten cyclical, multiparous, and pasture raised beef cows were divided into two groups: control group (n=5) and eCG group (n=5). In 30 day interval, all animals were synchronized with the same estrogen/progesterone based protocol, totalizing 8 re-synchronizations. Cows in the treatment group received 300IU eCG 48 hours prior to the presumable ovulation. Ultrassound examinations were performed on Day 4 of the protocol (approximately 1.5 days after follicle recruitment) to count antral follicles, on Day 10, to count antral follicles and to measure size of the largest follicle and on Day 18 to measure the diameter of the CL. No difference (P>0.05) between follicular growth and size of the pre-ovulatory follicle was reported between groups. Cows treated with eCG had a larger (P<0.05) CL and increased (P<0.05) ovulation rate (18mm and 92%, respectively) when compared with control group (14.1mm and 80%, respectively). Furthermore, consecutive treatments did not affect CL nor ovulation rates. In conclusion, eCG treatment increased CL size and ovulation rate even after 8 consecutive treatments.(AU)

A gonadotrofina coriónica equina (ECG) é uma glicoproteína produzida nos cálices endometriais da égua. Em bovinos, é utilizada em protocolos de sincronização do estro. Estudos têm mostrado que ela é potencialmente imunogênica e seu efeito pode diminuir depois de utilização repetida. O objetivo do presente trabalho foi avaliar a dinâmica folicular, o diâmetro do corpo lúteo (CL) e taxa de ovulação em vacas bos indicus submetidas a um protocolo de sincronização estral com eCG por oito vezes. Dez vacas de corte, cíclicas, multíparas e solteiras foram divididas em dois grupos: grupo controle (n=5) e grupo eCG (n=5). Em um intervalo de 30 dias, os animais foram sincronizados com um protocolo de estrógeno/progesterona, totalizando 8 re-sincronizações. Os animais do grupo tratamento receberam 300UI eCG 48 horas antes da provável ovulação. Exames ultrasonográficos foram realizados no dia 4 do protocolo (aproximadamente 1,5 dias após o recrutamento folícular), para contar folículos antrais, no dia 10, contar folículos antrais e medir o tamanho do maior folículo e, no dia 18, para medir o diâmetro do CL. Não foi encontrada diferença (P>0,05) entre folículos no dia 4 ou 10. Vacas tratadas com eCG tinham um maior (P<0.05) CL e elevada (P<0.05) taxa de ovulação (18mm e 92%, respectivamente) quando comparadas ao grupo controle (14,1mm e 80%, respectivamente). Além disso, tratamentos consecutivos não afetaram o CL nem as taxas de ovulação. Em conclusão, o tratamento com eCG aumentou o tamanho do CL e taxa de ovulação, mesmo depois de 8 tratamentos consecutivos.(AU)

Efeitos do manejo no período pré-parto sobre o crescimento e a saúde dos bezerros

O período pré-parto ou período seco da vaca leiteira é importante não apenas para o desenvolvimento fetal,mas também para a intensa involução e regeneração da glândula mamária, os quais são fatores que determinam a produção leiteira da vaca na próxima lactação (Capuco et al., 1997; Sorensenet al., 2006). Além disso, o período de transição é caracterizado por disfunção imune e desafios metabólicos,o que leva ao uso de diferentes estratégias nutricionais e de manejo durante o pré-parto,visando melhorar o desempenho da vaca no período pós-parto (revisadopor Mallard et al.,1998; Drackley, 1999; bigstockphoto. com O período de transição é caracterizado por disfunção imune e desafios metabólicos,o que leva ao uso de diferentes estratégias nutricionais e de manejo durante o pré-parto,visando melhorar o desempenho da vaca no período pós-parto. 10 Cadernos Técnicos de Veterinária e Zootecnia, nº 81 - junho de 2016Tao e Dahl, 2013).

Maternal use of flaxseed oil during pregnancy and lactation prevents morphological alterations in pancreas of female offspring from rat dams with experimental diabetes.

Nutritional recommendations have promoted the increased need to consume n-3 polyunsaturated fatty acids. Flaxseed is the richest dietary source of n-3 fatty acids among plant sources and is widely used for its edible oil. This study aimed to investigate whether maternal use of flaxseed oil has effects on pancreas morphology in the female offspring of diabetic mothers. Female Wistar rats (n = 12) were induced into diabetes by a high-fat diet and low dose of streptozotocin. After confirmation of the diabetes, rats were mated, and once pregnancy was confirmed, they were allocated into three groups (n = 6): high-fat group (HG); flaxseed oil group (FOG); and control group (CG) (non-diabetic rats). At weaning, female offspring (n = 6/group) received standard chow diet. The animals were euthanized at 180 days. Pancreas was collected for histomorphometric and immunohistochemistry analysis. HG showed hypertrophy of pancreatic islets (P < 0.0001), whereas FOG offspring had islets with smaller diameters compared to HG (P < 0.0001). HG offspring showed higher percentage of larger (P = 0.0061) and lower percentage of smaller islets (P = 0.0036). HG showed lower islet insulin immunodensity at 180 days (P < 0.0001), whereas FOG was similar to CG (P < 0.0001). Flaxseed oil reduced the damage caused by maternal hyperglycaemia, promoting normal pancreas histomorphometry and ß-cell mass in female offspring.