Maternal instinct of imported meat direction cattle and ethology of their calves

The examination of maternal qualities in the ethology of cows and their young offspring, derived from the study on adaptability and productivity of second and third-generation Aberdeen Angus cattle imported to Kazakhstan from Canadian and European selection, is presented in this paper. The findings indicate that Canadian heifers, belonging to the second generation, displayed extended feeding behavior throughout the day, dedicating 33.2 minutes or 2.2% more time to feeding compared to their European counterparts (P < 0.001). Similar disparities between groups were observed in the duration of the ruminant process. Moreover, Canadian heifers consumed water for an additional 2 minutes or 0.6%, which can be attributed to their higher daily feed intake. The calving process of Aberdeen Angus cows generally proceeded smoothly, demonstrating a well-developed maternal instinct towards their offspring. Notably, calves born from Canadian cows exhibited greater agility and achieved the ability to stand on their feet in a shorter time, with an average duration of 41.0 ± 1.60 minutes, which was 11.7% faster than European calves. Additionally, Canadian calves displayed a shorter time to locate their mother's breast, with an average duration of 68.0 ± 7.70 minutes.(AU)

The Influence of porcine parity on colostrum cytokine levels and their passive transfer to piglets / A influência da paridade suína na diferença dos níveis de citocinas no colostro e na transferência passiva para leitões

The limited ability of newborn piglets to produce cytokines may influence lymphocyte development and response to antigen exposure. As a result, colostrum intake is crucial because it contains nutrients that contribute to immune system development in piglets. Our goal was to investigate the effect of sow parity on the transfer of maternal cytokines to nursing piglets. Sixty piglets from nine sows were divided into six groups: piglets from gilts or sows kept with their dams and allowed to suckle normally; piglets from gilts or sows having their dams exchanged and then allowed to suckle normally; piglets from gilts or sows isolated from their dams and bottle-fed a commercial milk replacer formula for pigs. All piglets remained in the diet groups for 24 hours after birth. Concentrations of cytokines in colostrum and serum of gilt/ sows and serum of piglets were then evaluated. The 13 evaluated cytokines had higher concentrations in colostrum and serum of sows than in gilts. Concentrations of GM-CSF, IFNγ, IL-1α, IL-1ß, IL-2, IL-4, IL-6, IL-10, IL-12, IL-18, and TNFα were higher in piglets suckling sows. Piglets that received commercial formula showed higher concentrations of the cytokines IL1-RA and IL-8 than piglets fed colostrum. This outcome can influence piglets' development into adulthood. In short, our findings demonstrated that maternal parity influenced colostrum cytokine composition and its maternal transfer patterns.(AU)

A capacidade limitada dos leitões recém-nascidos de produzir citocinas pode influenciar o desenvolvimento de linfócitos e a resposta à exposição ao antígeno. Portanto, a ingestão de colostro é importante porque contém nutrientes, que contribuem para o desenvolvimento do sistema imunológico do leitão. O objetivo do estudo foi investigar o efeito da paridade da porca na transferência de citocina materna para leitões lactentes. Sessenta leitões de nove porcas foram divididos em seis grupos: leitões de marrãs/porcas mantidas com suas próprias mães e amamentadas normalmente; leitões de marrãs/porcas que foram trocados de mães e amamentados normalmente; leitões de marrãs/porcas que foram isolados das mães e alimentados com mamadeira com substituto do leite para suínos. Os leitões permaneceram nos grupos por 24 horas após o nascimento. Foram avaliadas as concentrações de citocinas no colostro e plasma das marrãs/porcas e no plasma dos leitões. O colostro e o plasma das porcas apresentaram maiores concentrações das 13 citocinas analisadas do que as marrãs. No mesmo sentido, as concentrações de GM-CSF, IFNγ, IL-1α, IL-1ß, IL-2, IL-4, IL-6, IL-10, IL-12, IL-18 e TNFα foram significantemente maiores nos leitões que mamaram o colostro de porcas. Os leitões que receberam fórmula comercial apresentaram, em especial, concentrações das citocinas IL1-RA e IL-8 superiores aos leitões amamentados com colostro. Isso pode influenciar o desenvolvimento até a fase adulta. Portanto, nossos dados demonstraram que a paridade materna influenciou a composição das citocinas do colostro, bem como as características das citocinas na transferência materna.(AU)

DNA methylation level of gene SIRT1 in ram spermatozoa and relationship with fertilizing ability according to breed and age

Background: Effect of the epigenetic factors on the male fertility is well proofed. Sperm acts as a carrier of genetic material, and its DNA methylome can affect maternal pregnancy rate and offspring phenotype. However, the research on the DNA methylation in the spermatozoids of livestock males, in particular rams, is still limited. To best of our knowledge the data about as a global as well as gene specific DNA methylation in ram spermatozoa from different breeds and ages are missed in the scientific literature. The present study was designed to analyze the relationship between methylation levels of the important for spermatogenesis gene SIRT1 in spermatozoa and fertilizing ability of sperm in rams from different breeds and ages. Materials, Methods & Results: The ejaculates of 16 rams from Lacaune, East Friesian and Assaf breeds at age between 18 to 96 months were evaluated. The kinematic parameters of 2 semen samples from each animal were estimated by CASA. The separated spermatozoa were used for DNA extraction followed by bisulfite conversion. The DNA methylation of SIRT1 was detected through quantitative methylation-specific PCR using 2 sets of primers designed specifically for bisulfite-converted DNA sequences to attach methylated and unmethylated sites. The breed and age effect on the gene SIRT1 methylation by ANOVA was estimated. Experimental females included 393 clinically healthy milk ewes (Lacaune, n = 131; East Friesian sheep, n = 100 and Assaf, n = 162) in breeding season. Reproductive performances (conception rate at lambing, lambing percentage and fecundity) of ewes, inseminated by sperm of the investigated rams, were statistically processed. ANOVA showed that the animal breed influences significantly on the level of DNA methylation of gene SIRT1 in ram spermatozoa (P = 0.002) An average value of DNA methylation of SIRT1 in ram sperm from Lacaune breed was significantly higher than in Assaf and East Friesian (81.21 ± 15.1% vs 36.7 ± 14.2% and 38.3 ± 18.6 respectively, P < 0.01). The highest percent of SIRT1 methylation was observed in old animals compared to the young and middle-age. Moderate and strong correlations (r from 0.44 to 0.71, P < 0.05) between the methylation level of the SIRT1 gene in rams' sperm and reproductive parameters of inseminated ewes in all breeds were established. Discussion: Our data are the first message about the effect of breed on the specificity of DNA methylation of gene SIRT1 in ram spermatozoa. These results demonstrated an existence of the sheep breeds with high and low level of DNA methylation of gene SIRT1 in ram sperm. Although the effect of age on the methylation level in sperm is still discussable, our results showed a moderate correlation between age and methylation level of SIRT1 in spermatozoa of rams. Taking into account that DNA methylation in sperm is stabilized with puberty onset and is a heritable epigenetic modification, it can be a promising marker of sperm quality in animal breeding. In all investigated breeds the rams with relatively high level of DNA methylation of gene SIRT1 in spermatozoa (50-68%) demonstrated a high conception rate at lambing (> 70%). In conclusion, the DNA methylation level of the SIRT1 gene in ram spermatozoa is determined by both the breed and the age of the animals and correlates with fertilizing ability of sperm.

Influence of management and lactation order in the serum concentrations of proteins, metabolites, minerals, and enzymes of Bonsmara breed cows / Influência da gestação e ordem de lactação nas concentrações séricas de proteínas, metabólitos, minerais e enzimas de vacas da raça Bonsmara

This study aimed to evaluate the influence of gestation and lactation order on serum concentrations of proteins, metabolites, minerals, and enzymes in first-, second-, and third-lactation order Bonsmara cows. The Bonsmara breed, originated in South Africa, stands out for its tolerance to heat and productive characteristics, such as meat quality, high fertility, sexual precocity, ease of calving, and good maternal ability. These characteristics make the breed a genetic alternative for crossbreeding with zebu breeds. Blood samples were collected from 34, 29, and 30 first-, second-, and third-lactation order cows, respectively, totaling 93 cows. The samples were processed in an automatic multichannel analyzer using Labtest Diagnóstica® kits. The Kruskal-Wallis test was chosen to compare the values between lactation orders. The Mann-Whitney test was used to compare pregnant and non-pregnant cows within lactation orders. Among the analyzed constituents, the lactation order significantly influenced only the serum albumin concentration (ALB) (p<0.0001). Gestation significantly influenced the A:G ratio (p=0.034) in third-lactation cows, and cholesterol (Chol) (p=0.004), triglycerides (TRI) (p<0.0001), inorganic phosphorus (iP) (p=0.033), iron (Fe) (p=0.001), aspartate aminotransferase (AST) (p=0.018), and alkaline phosphatase (ALP) (p=0.039) in second-lactation cows and the general group. Creatinine (Crea) (p<0.0001) was influenced only in the general group. Therefore, gestation and lactation order significantly influenced the concentration of several biochemical serum constituents in Bonsmara cows, especially second-lactation order cows.

Objetivou-se avaliar a influência da gestação e ordem de lactação nas concentrações séricas de proteínas, metabólitos, minerais e enzimas de vacas da raça Bonsmara de primeira, segunda e terceira ordem de lactação. A raça Bonsmara, originada na África do Sul, se destaca por sua tolerância ao calor, e caracteristicas produtivas, como a qualidade da carne, a alta fertilidade, precocidade sexual, facilidade ao parto e boa habilidade materna. Essas características tornam a raça uma alternativa genética para realização de cruzamentos com raças zebuínas. Foram colhidas amostras de sangue de 93 vacas, sendo 34 de primeira ordem de lactação, 29 de segunda ordem de lactação e 30 de terceira ordem de lactação. As amostras foram processadas em analisador automático multicanal, utilizando kits da Labtest Diagnóstica®. Para confrontar os valores entre as ordens de lactação optou-se pelo teste Kruskall-Wallis. Para comparar vacas gestantes e não gestantes dentro das ordens de lactação, foi utilizado o teste de Mann-Whitney. Dos constituintes analisados, a ordem de lactação influenciou significativamente apenas a concentração sérica de albumina (ALB) (p<0,0001). A gestação influenciou significativamente na relação A:G (p=0,034), nas vacas de terceira lactação, no colesterol (COL) (p=0,004), triglicérides (TRI) (p<0,0001), fósforo inorgânico (Pi) (p=0,033), ferro (Fe) (p=0,001), aspartato aminotransferase (AST) (p=0,018) e fosfatase alcalina (FAL) (p=0,039) nas de segunda ordem e no valor do grupo geral. A creatinina (Crea) (p<0,0001) foi influenciada somente no grupo geral. Conclui-se que a gestação e ordem de lactação influenciou significativamente na concentração de vários constituintes bioquímicos séricos de vacas da raça Bonsmara, em especial nas de segunda ordem de lactação.

Influência da genética e dos métodos de conservação sobre a qualidade do sêmen suíno / Influence of genetics and conservation methods on the quality of swine semen

A demanda do mercado impulsionou o melhoramento genético na suinocultura caracterizado pelo cruzamento entre linhagens e raças distintas a fim de possibilitar o aproveitamento da heterose. Esse melhoramento acelerado ocorreu em decorrência da inseminação artificial e manipulação do sêmen, associado ao emprego de diluentes e técnicas de refrigeração. Sendo assim, esta revisão tem como objetivo compilar o conhecimento acerca da influência genética e dos métodos de conservação sobre a qualidade do sêmen suíno, além de discutir a composição e eficiência dos principais diluentes e crioprotetores destinados à conservação espermática nesta espécie. Inicialmente, os animais eram selecionados baseados em características produtivas como habilidade materna, qualidade de carcaça e desempenho. Contudo, a fertilidade do reprodutor, caraterizada pela qualidade espermática e libido, é extremamente importante para indústria suinícola uma vez que determina, o potencial produtivo do plantel indiretamente. Evidências demonstram que os parâmetros espermáticos sofrem influência da genética, sendo que cada raça se destaca numa determinada característica seminal. Além disso, o manejo, idade, alimentação, sazonalidade, as características intrínsecas do espermatozoide e os métodos de conservação do ejaculado também determinam sua viabilidade. Apesar de preconizado devido à fácil execução e ótimos resultados, o sêmen refrigerado tem como limitador a produção excessiva de espécies reativas de oxigênio. Da mesma forma, o congelamento do ejaculado promove alterações espermáticas em virtude do choque térmico. Sendo assim, o emprego de diluentes e crioprotetores propícios que possibilitem a manutenção a longo prazo da viabilidade espermática é imprescindível para ambos os processos.

The market demand promoted the genetic improvement in swine farming characterized by the crossing between different strains and breeds to make possible the use of heterosis. This accelerated improvement occurred due to artificial insemination and semen manipulation, associated with the use of extenders and refrigeration techniques. Therefore, this review aims to compile knowledge about the genetic influence and conservation methods on the quality of swine semen, besides to discussing the composition and efficiency of the main extenders and cryoprotectants intended for sperm conservation in this species. Initially, animals were selected based on productive traits such as maternal ability, carcass quality, and performance. However, male fertility, characterized by sperm quality and libido, is extremely important for the swine industry as it determines the productive potential of the herd indirectly. Evidences demonstrates that sperm parameters are influenced by genetics, with each race standing out in certain seminal trait. In addition, the management, age, feeding, seasonality, the intrinsic characteristics of the sperm cell, and the methods of ejaculate conservation also determine its viability. Despite being recommended due to its easy execution and excellent results, refrigerated semen has the excessive production of reactive oxygen species as a limiter. Likewise, the ejaculate freezing promotes sperm changes due to heat shock. Therefore the use of suitable extenders and cryoprotectants that allow the long-term maintenance of sperm viability is essential for both processes.

Influence of non-genetic factors on the maternal ability of Santa Inês ewes / Influência de fatores não-genéticos na habilidade materna de ovelhas Santa Inês

ABSTRACT: The aim of this study was to evaluate the influence of different non-genetic effects on indicator traits for maternal ability in Santa Inês ewes. Data included performance records of 100 lambs (males and females) born from 59 dams, from 2009 to 2012. The analyzed traits were birth weight (BW), weaning weight (WW), average daily gain from birth until weaning (ADGBW), total litter weight at birth (TLWB), and total litter weight at weaning (TLWW). The effects analyzed were the year of birth of the lamb, birth season, dam age at lambing, dam weight at lambing, sex of the lamb, lamb birth type, interaction between sex and birth type, and interaction between sex and birth season. SAS® software (SAS University Edition, USA) was used for calculation of the analysis of variance, means, and Pearson correlation coefficients. With the exception of the birth season, all the other environmental effects evaluated had a significant influence on at least one of the studied traits. The correlation estimates ranged from low to high and were either positive or negative. Birth weight was negatively correlated with the birth type and influenced positively all the other performance traits evaluated. The maternal ability of Santa Inês ewes was more clearly influenced by the age and weight of the dam at lambing, and the lamb birth type.

RESUMO: O objetivo deste estudo foi avaliar a influência de diferentes efeitos não-genéticos sobre características indicadoras de habilidade materna em ovelhas da raça Santa Inês. Os dados utilizados incluíram registros de desempenho de 100 cordeiros (machos e fêmeas) filhos de 59 ovelhas, nascidos de 2009 a 2012. As características analisadas foram peso ao nascimento (PN), peso ao desmame (PD), ganho médio diário do nascimento ao desmame (GMND), peso total das crias ao nascer (PTCN) e peso total das crias ao desmame (PTCD). Os efeitos analisados foram ano de nascimento da cria, estação de nascimento, idade da mãe ao parto, peso da mãe ao parto, sexo da cria, tipo de nascimento da cria, interação entre sexo e tipo de nascimento, e interação entre sexo e estação de nascimento. O programa SAS (SAS University Edition, EUA) foi utilizado para o cálculo de análise de variância, médias e coeficientes de correlação de Pearson. Com exceção da estação de nascimento, os demais efeitos avaliados exerceram influência significativa sobre pelo menos uma das características estudadas. As estimativas de correlação variaram de baixa a alta magnitude e foram tanto positivas quanto negativas. O peso da cria ao nascimento foi negativamente correlacionado com o tipo de nascimento e influenciou positivamente todas as outras características de desempenho avaliadas. A habilidade materna de ovelhas Santa Inês foi mais claramente influenciada pela idade e peso da mãe ao parto e pelo tipo de nascimento da cria.

Influence of non-genetic factors on the maternal ability of Santa Inês ewes / Influência de fatores não-genéticos na habilidade materna de ovelhas Santa Inês

The aim of this study was to evaluate the influence of different non-genetic effects on indicator traits for maternal ability in Santa Inês ewes. Data included performance records of 100 lambs (males and females) born from 59 dams, from 2009 to 2012. The analyzed traits were birth weight (BW), weaning weight (WW), average daily gain from birth until weaning (ADGBW), total litter weight at birth (TLWB), and total litter weight at weaning (TLWW). The effects analyzed were the year of birth of the lamb, birth season, dam age at lambing, dam weight at lambing, sex of the lamb, lamb birth type, interaction between sex and birth type, and interaction between sex and birth season. SAS® software (SAS University Edition, USA) was used for calculation of the analysis of variance, means, and Pearson correlation coefficients. With the exception of the birth season, all the other environmental effects evaluated had a significant influence on at least one of the studied traits. The correlation estimates ranged from low to high and were either positive or negative. Birth weight was negatively correlated with the birth type and influenced positively all the other performance traits evaluated. The maternal ability of Santa Inês ewes was more clearly influenced by the age and weight of the dam at lambing, and the lamb birth type.(AU)

O objetivo deste estudo foi avaliar a influência de diferentes efeitos não-genéticos sobre características indicadoras de habilidade materna em ovelhas da raça Santa Inês. Os dados utilizados incluíram registros de desempenho de 100 cordeiros (machos e fêmeas) filhos de 59 ovelhas, nascidos de 2009 a 2012. As características analisadas foram peso ao nascimento (PN), peso ao desmame (PD), ganho médio diário do nascimento ao desmame (GMND), peso total das crias ao nascer (PTCN) e peso total das crias ao desmame (PTCD). Os efeitos analisados foram ano de nascimento da cria, estação de nascimento, idade da mãe ao parto, peso da mãe ao parto, sexo da cria, tipo de nascimento da cria, interação entre sexo e tipo de nascimento, e interação entre sexo e estação de nascimento. O programa SAS (SAS University Edition, EUA) foi utilizado para o cálculo de análise de variância, médias e coeficientes de correlação de Pearson. Com exceção da estação de nascimento, os demais efeitos avaliados exerceram influência significativa sobre pelo menos uma das características estudadas. As estimativas de correlação variaram de baixa a alta magnitude e foram tanto positivas quanto negativas. O peso da cria ao nascimento foi negativamente correlacionado com o tipo de nascimento e influenciou positivamente todas as outras características de desempenho avaliadas. A habilidade materna de ovelhas Santa Inês foi mais claramente influenciada pela idade e peso da mãe ao parto e pelo tipo de nascimento da cria.(AU)

Desenvolvimento embrionário: quando avaliar o fenótipo e sua relação com o genótipo / Embryonic development: when to evaluate its phenotype and its relationship with genotype

Durante as últimas décadas, a suinocultura vivencia um processo de intensa seleção genética. Dentre as características reprodutivas, a taxa ovulatória sofreu a avanços significativos e, como consequência, o aumento do tamanho da leitegada em fêmeas suínas contemporâneas é evidente. No entanto, essa pressão de seleção gerou também características indiretas indesejáveis, como o baixo peso ao nascimento e grande variabilidade de peso ao nascimento dentro de uma mesma leitegada. Desta forma, durante os últimos anos, inúmeros estudos buscaram entender os principais aspectos relacionados ao desenvolvimento embrionário e pré-natal em suínos. A capacidade de elucidar aspectos relacionados à regulação do desenvolvimento embrionário e placentário, aos genes centrais e marcadores moleculares que estão relacionados ao adequado desenvolvimento e qualidade embrionária contribuem para a compreensão da reprodução básica e facilitam o entendimento das relações materno-embrionárias no período gestacional.

During the last few decades, the swine industry has undergone an intense process of genetic selection. Among the reproductive characteristics, the ovulation rate has undertaken significant advances , and, consequently, the increase in litter size is evident in contemporaneous sows. However, the selection pressure also resulted in undesired indirect characteristics, as the low birth weight and birth weight variability within the litter. Therefore, during the last few years, many studies have shed light on the aspects related to embryonic and prenatal development in pigs. The ability to understand how embryonic development is regulated, the central genes and molecular markers that are related to appropriate development, and embryonic quality contribute to the understanding of basic reproduction and facilitates the understanding of embryo-maternal relationships.

Necrotizing placentitis in a cow caused by Bacillus cereus / Placentite necrotizante em uma vaca por Bacillus cereus

This report described a case of necrotizing placentitis caused by Bacillus cereus in a cow associated with abortion and maternal lethality. The etiological diagnosis of placentitis by B. cereus was based on histopathology of placenta, cytology and bacterial isolation from intrauterine aminiotic fluid in retained placenta and further characterization of the pathogen by the MALDI-TOF. Although, B. cereus abortions are sporadic, the bacterium has the ability to release necrotizing toxins that can lead to placentitis, fetal death and abortion.(AU)

Este relato descreve a placentite necrotizante causada por Bacillus cereus em uma vaca associada a aborto e mortalidade materna. O diagnóstico etiológico de placentite por B. cereus foi baseado na histopatologia da placenta, citologia e isolamento bacteriano partir do líquido aminiótico em placenta retida e identificação do patógeno pela técnica de MALDI-TOF. Embora abortos por B. cereus sejam esporádicos, a bactéria tem a capacidade de liberar toxinas necrotizantes que podem levar a placentite e aborto.(AU)

Direct and maternal annual genetic changes for selected traits at weaning and yearling in beef cattle

Heritability and direct and maternal genetic changes were estimated in Nellore cattle for the following traits: birth to weaning weight gain (BWG), weaning to yearling weight gain (YWG), weaning conformation (WC), weaning precocity (WP), weaning muscling (WM), yearling conformation (YC), yearling precocity (YP), yearling muscling (YM) and yearling scrotal circumference (SC). Direct and maternal heritability for weaning traits were 0.21±0.03 and 0.13±0.01 (BWG); 0.19±0.03 and 0.07±0.01 (WC); 0.22±0.03 and 0.07±0.01 (WP); 0.20±0.03 and 0.07±0.01 (WM), respectively. For yearling traits, direct heritability were 0.19±0.04 (YWG); 0.32±0.05 (YC); 0.37±0.05 (YP); 0.38±0.05 (YM) and 0.41±0.04 (SC). Positive and significant direct genetic changes (p < 0.05) were found for all traits, except for WC (p = 0.09), equal to 0.138 kg year-1 (BWG), 0.003 units year-1 (WC), 0.011 units year-1 (WP), 0.009 units year-1 (WM), 0.132 kg year-1 (YWG), 0.003 units year-1 (YC), 0.011 units year-1 (YP), 0.011 units year-1 (YM) and 0.020 cm year-1 (SC), indicating favorable genetic gains in the period. For weaning traits, we obtained negative and non-significant (p > 0.05) maternal genetic trends, with values of -0.084 kg year-1 (BWG), -0.004 units year-1 (WC), -0.004 units year-1 (WP) and -0.004 units year-1 (WM). Thus, greater emphasis should be given for maternal genetic merit of weaning traits in this population, if improvements in maternal ability were desirable.(AU)

Direct and maternal annual genetic changes for selected traits at weaning and yearling in beef cattle

Heritability and direct and maternal genetic changes were estimated in Nellore cattle for the following traits: birth to weaning weight gain (BWG), weaning to yearling weight gain (YWG), weaning conformation (WC), weaning precocity (WP), weaning muscling (WM), yearling conformation (YC), yearling precocity (YP), yearling muscling (YM) and yearling scrotal circumference (SC). Direct and maternal heritability for weaning traits were 0.21±0.03 and 0.13±0.01 (BWG); 0.19±0.03 and 0.07±0.01 (WC); 0.22±0.03 and 0.07±0.01 (WP); 0.20±0.03 and 0.07±0.01 (WM), respectively. For yearling traits, direct heritability were 0.19±0.04 (YWG); 0.32±0.05 (YC); 0.37±0.05 (YP); 0.38±0.05 (YM) and 0.41±0.04 (SC). Positive and significant direct genetic changes (p 0.05) maternal genetic trends, with values of -0.084 kg year-1 (BWG), -0.004 units year-1 (WC), -0.004 units year-1 (WP) and -0.004 units year-1 (WM). Thus, greater emphasis should be given for maternal genetic merit of weaning traits in this population, if improvements in maternal ability were desirable.

Efeito do escore da condição corporal materna no desenvolvimento in vitro das células tronco mesenquimais do cordão umbilical de fetos caprinos / Effect of the score of maternal body condition in the in vitro development of the mesenquimal trunk cells in the umbilical cord of caprine fetes

O objetivo do trabalho foi avaliar o efeito do escore da condição corporal (ECC) materno sobre a capacidade de isolamento, expansão e caracterização de células-tronco mesenquimais (CTMs) derivadas do cordão umbilical de fetos caprinos. Para tanto, dezenove cabras mestiças adultas, pluríparas foram agrupadas de acordo com o ECC, atribuindo-se um escore de 1-5, (GB) grupo baixo com menor ECC, (2,3±0,1, GB, n = 9) e (GA) grupo alto com maior ECC (2,9±0,1, GA, n = 10). Durante o parto, fragmentos do cordão umbilical foram coletados e cultivados in vitro e avaliados a taxa de proliferação celular. Nenhum efeito significativo do ECC foi encontrado para os parâmetros considerados.

The objective of this study was to evaluate the effect of the maternal body condition score (ECC) on the ability to isolate, expand and characterize mesenchymal stem cells (MTCs) derived from the umbilical cord of goat fetuses. Nineteen crossbred adult crossbred goats were grouped according to ECC, giving a score of 1-5 (GB) low group with lower ECC, (2.3±0.1, GB, n = 9 ) and (GA) high group with higher ECC (2.9±0.1, GA, n = 10). During delivery, umbilical cord fragments were collected and cultured in vitro and the rate of cell proliferation was evaluated. No significant effect of ECC was found for the parameters considered.

Efeito do escore da condição corporal materna no desenvolvimento in vitro das células tronco mesenquimais do cordão umbilical de fetos caprinos / Effect of the score of maternal body condition in the in vitro development of the mesenquimal trunk cells in the umbilical cord of caprine fetes

O objetivo do trabalho foi avaliar o efeito do escore da condição corporal (ECC) materno sobre a capacidade de isolamento, expansão e caracterização de células-tronco mesenquimais (CTMs) derivadas do cordão umbilical de fetos caprinos. Para tanto, dezenove cabras mestiças adultas, pluríparas foram agrupadas de acordo com o ECC, atribuindo-se um escore de 1-5, (GB) grupo baixo com menor ECC, (2,3±0,1, GB, n = 9) e (GA) grupo alto com maior ECC (2,9±0,1, GA, n = 10). Durante o parto, fragmentos do cordão umbilical foram coletados e cultivados in vitro e avaliados a taxa de proliferação celular. Nenhum efeito significativo do ECC foi encontrado para os parâmetros considerados.(AU)

The objective of this study was to evaluate the effect of the maternal body condition score (ECC) on the ability to isolate, expand and characterize mesenchymal stem cells (MTCs) derived from the umbilical cord of goat fetuses. Nineteen crossbred adult crossbred goats were grouped according to ECC, giving a score of 1-5 (GB) low group with lower ECC, (2.3±0.1, GB, n = 9 ) and (GA) high group with higher ECC (2.9±0.1, GA, n = 10). During delivery, umbilical cord fragments were collected and cultured in vitro and the rate of cell proliferation was evaluated. No significant effect of ECC was found for the parameters considered.(AU)

Factors influencing establishment of the ovarian reserve and their effects on fertility

A reserve of primordial follicles is set up in the ovaries of fetuses or neonates, depending on the species, and serves as the source of developing follicles throughout the reproductive lifespan. This review focuses on the cellular and molecular mechanisms currently known to control the establishment of this reserve, and their regulation by environmental factors. Most mutations in genes controlling germ cell proliferation and survival, meiosis or follicle assembly lead to the absence of primordial follicles or a sharp reduction in their number, incompatible with fertility in adults. Inadequate maternal nutrition affects the cellular metabolism, increases the oxidative stress and delays follicle formation in fetal ovaries. Despite the existence of compensation mechanisms of some developmental processes, the early-life nutritional environment imprints the long-term ability of follicles to enter growth and develop in adult ovaries. However, maternal undernutrition, overfeeding or high-fat diet during the establishment of the ovarian reserve does not seem to affect the fertility of the female offspring, unless their metabolism or neuroendocrine status is altered. Exposure of fetal or neonatal ovaries to excess steroids inhibits or stimulates follicle formation in a complex manner depending on the nature of the steroid, the dose and the animal species. Estrogens can control follicle formation through intra-ovarian mechanisms involving members of the TGF-beta family such as activin and BMP2. Early-life exposure to synthetic estrogens or environmental pollutants with estrogen-like activity impairs meiotic progression and follicle assembly, and affects long-term primordial follicle activation in adult ovaries. The effects of compounds with estrogen-like activity on the ovarian reserve can be transmitted to several generations through the female germline. Further investigations are needed to establish the earlylife effects of the environmental factors on the female reproductive lifespan and decipher the mechanisms of their epigenetic effects on the size and quality of the ovarian reserve.(AU)

Factors influencing establishment of the ovarian reserve and their effects on fertility

A reserve of primordial follicles is set up in the ovaries of fetuses or neonates, depending on the species, and serves as the source of developing follicles throughout the reproductive lifespan. This review focuses on the cellular and molecular mechanisms currently known to control the establishment of this reserve, and their regulation by environmental factors. Most mutations in genes controlling germ cell proliferation and survival, meiosis or follicle assembly lead to the absence of primordial follicles or a sharp reduction in their number, incompatible with fertility in adults. Inadequate maternal nutrition affects the cellular metabolism, increases the oxidative stress and delays follicle formation in fetal ovaries. Despite the existence of compensation mechanisms of some developmental processes, the early-life nutritional environment imprints the long-term ability of follicles to enter growth and develop in adult ovaries. However, maternal undernutrition, overfeeding or high-fat diet during the establishment of the ovarian reserve does not seem to affect the fertility of the female offspring, unless their metabolism or neuroendocrine status is altered. Exposure of fetal or neonatal ovaries to excess steroids inhibits or stimulates follicle formation in a complex manner depending on the nature of the steroid, the dose and the animal species. Estrogens can control follicle formation through intra-ovarian mechanisms involving members of the TGF-beta family such as activin and BMP2. Early-life exposure to synthetic estrogens or environmental pollutants with estrogen-like activity impairs meiotic progression and follicle assembly, and affects long-term primordial follicle activation in adult ovaries. The effects of compounds with estrogen-like activity on the ovarian reserve can be transmitted to several generations through the female germline. Further investigations are needed to establish the earlylife effects of the environmental factors on the female reproductive lifespan and decipher the mechanisms of their epigenetic effects on the size and quality of the ovarian reserve.

Trophoblast of domestic and companion animals: basic and applied clinical perspectives

The trophoblast is the single most important functional structure of the placenta that mediates the attachment of the blastocyst to the endometrium. Trophoblast has the capability to proliferate in concert with the uterine epithelium to form the only site for nutrient and metabolic exchange between the fetus and dam throughout pregnancy. Trophoblast is made up of a remarkable versatile epithelium showing great capacity for invasion, cell fusion, hormone production, specific nutrient absorption, selective transport, active metabolism, and has the ability to resist maternal immunological attack. These functions are attributed to its inherent ability to synthesize many developmental factors or molecular regulators. While there is an abundance of publications available on the structural, functional, and clinical relevance of the placenta in various mammalian species, a comprehensive review on the comparative aspects of the trophoblast of domestic and companion animals is lacking. Besides, a timely description on the clinical perspective on the functional aspects of the trophoblast in relation to pregnancy diagnosis, placental insufficiency, pregnancy loss, and structural abnormalities of domestic and companion animals is necessary. A brief description on the basic chronology of events in each animal is followed by the applied clinical perspectives of trophoblast. Both the above aspects of trophoblasts of domestic and companion animals including the terminologies are summarized in tables to facilitate discussion.

Trophoblast of domestic and companion animals: basic and applied clinical perspectives

The trophoblast is the single most important functional structure of the placenta that mediates the attachment of the blastocyst to the endometrium. Trophoblast has the capability to proliferate in concert with the uterine epithelium to form the only site for nutrient and metabolic exchange between the fetus and dam throughout pregnancy. Trophoblast is made up of a remarkable versatile epithelium showing great capacity for invasion, cell fusion, hormone production, specific nutrient absorption, selective transport, active metabolism, and has the ability to resist maternal immunological attack. These functions are attributed to its inherent ability to synthesize many developmental factors or molecular regulators. While there is an abundance of publications available on the structural, functional, and clinical relevance of the placenta in various mammalian species, a comprehensive review on the comparative aspects of the trophoblast of domestic and companion animals is lacking. Besides, a timely description on the clinical perspective on the functional aspects of the trophoblast in relation to pregnancy diagnosis, placental insufficiency, pregnancy loss, and structural abnormalities of domestic and companion animals is necessary. A brief description on the basic chronology of events in each animal is followed by the applied clinical perspectives of trophoblast. Both the above aspects of trophoblasts of domestic and companion animals including the terminologies are summarized in tables to facilitate discussion.(AU)

Negative energy balance and metabolic stress in relation to oocyte and embryo quality: an update on possible pathways reducing fertility in dairy cows

A negative energy balance in metabolically compromised high producing dairy cows has been shown to influence oocyte and embryo quality. However, the possible involved pathways needed more attention to better understandspecific deleterious effects. Oocyte maturation is the first process to be scrutinized. Because many possible metabolic factors might directly impact oocyte quality, systematic in vitroapproaches were used to investigate the effects of oocyte maturation under elevated NEFA concentrations. Blastocysts originating from NEFA-exposed oocytes showed a lower cell number, an increased apoptotic cell index, signs of glucose intolerance, sensitive to oxidative stress and mitochondrial dysfunction. Defining these embryos’ transcriptome and epigenome signatures revealed changes in DNA methylation patterns. Long-term exposure of developing murine follicles to elevated NEFA concentrations showed to impair oocyte developmental competence even more. While little is known on how the oviductal micro-environment can change as a consequence of a negative energy balance, a validated in vitrobovine oviduct model offered some valuable insights on how NEFAs disturb oviductal cell physiology. NEFA exposure reduces cell proliferation, cell migration, sperm binding capacity and monolayer integrity. In addition, oviductal cells seem to play an active role in regulating luminal NEFA-concentrations through increased permeability, intracellular lipid accumulation and fatty acid metabolism. This might favour early embryo development. The establishment of a successful pregnancy largely depends on the ability of the embryo to interact with a properly prepared endometrium.

Estudo genético quantitativo de características de crescimento em bovinos Nelore de acordo com a ordem de parto das matrizes

Este estudo foi desenvolvido com o objetivo de inferir sobre o efeito da ordem de parto das matrizes (OP) sobre o crescimento pré-desmama dos animais mediante a obtenção de: parâmetros genéticos para o peso ao nascer (PN), ganho de peso do nascimento à desmama (GND) e peso à desmama (PD) de acordo com a OP; associações genéticas entre as características e entre as OP dentro de cada característica; além de tendências genéticas para cada característica e considerando cada OP. As informações fenotípicas e de pedigree utilizadas integram a base de dados do programa DeltaGen. A estimação de parâmetros genéticos e a predição do mérito genético dos animais para os efeitos genético-aditivos direto e materno foi realizada em análises bicaracterísticas e de regressão aleatória via inferência Bayesiana. Existe variabilidade genética para as características estudadas e a seleção realizada nos rebanhos tem promovido mudanças significativas para o efeito genético-aditivo direto. Isso requer especial atenção quanto ao peso ao nascer, devendo-se ponderá-lo nos índices para evitar problemas de parto, principalmente, em matrizes jovens. Em 2021, o programa DeltaGen implementou essa prática e espera-se que o peso ao nascer dos animais tenda a valores próximos à média da população. Por outro lado, a habilidade materna das matrizes não sofreu mudança genética ao longo do tempo considerado neste estudo, cabendo redefinir os índices de seleção neste sentido, caso seja desejada a obtenção de animais com maior habilidade materna. Nas populações estudadas não foram encontradas evidências robustas da existência de animais geneticamente plásticos, não sendo amparada, portanto, a seleção para desenvolvimento ponderal de animais da raça Nelore de acordo com a ordem de parto das matrizes.

This study was carried out with the aim of inferring the effect of the calving order (CO) on the pre-weaning growth of animals by obtaining: genetic parameters for birth weight (BW), birth to weaning weight gain (BWG) and weaning weight (WW) according to CO; genetic associations between traits and between CO within each trait; in addition to genetic trends for each trait and considering each CO. The phenotypic and pedigree information used are part of the DeltaGen program database. The estimation of genetic parameters and the prediction of the genetic merit of animals for direct and maternal genetic-additive effects were performed in two-trait and random regression analyzes via Bayesian inference. There is genetic variability for the studied traits and the selection carried out in the herds has promoted significant changes for the direct genetic-additive effect. This requires special attention regarding BW, which should be considered in the indexes to avoid birth problems, especially in heifers. In 2021, the DeltaGen program implemented this practice and it is expected that the BW of animals will tend to values close to the population mean. On the other hand, the maternal ability of the dams did not undergo genetic change over the time considered in this study, and it is necessary to redefine the selection indices in this sense, if it is desired to obtain animals with greater maternal ability. In the studied populations, robust evidence of the existence of genetically plastic animals was not found, therefore, the selection for weight development of Nelore animals according to the CO of the dams was not supported.

Parâmetros e ganhos genéticos em características de crescimento de bovinos Tabapuã da Bahia / Parameters and gains in genetic characteristics of Bahia Tabapuã bovine Growth

Compararam-se dois modelos (com ou sem o efeito materno) na estimativa de parâmetros genéticos por meio do fator de Bayes (FB) e do critério de informação da deviance (DIC). Adicionalmente, avaliaram-se as tendências genéticas, maternas e fenotípicas em características de crescimento de bovinos da raça Tabapuã do estado da Bahia. O modelo que incluiu o efeito materno proporcionou menores valores de FB (167629,2; 117341,2 e 124804,8) e DIC (174550,0; 120242,7 e 128037,2) para pesos aos 205 (P205), 365 (P365) e 550 (P550) dias de idade, respectivamente. As estimativas médias, a posteriori, das herdabilidades diretas e maternas foram 0,33; 0,43 e 0,44 e 0,15; 0,14 e 0,16 para as três características, respectivamente. As tendências genéticas para o efeito direto foram de 0,4415 e 0,3613kg/ano para P205 e P365 e representam incrementos de apenas 0,25 e 0,15% nas médias das características ao ano. As tendências genéticas maternas para as três características demonstraram perdas e indicam ausência de seleção de matrizes para boa habilidade materna. Apesar de existir variabilidade genética suficiente para justificar ganhos genéticos via seleção, estes e os ganhos fenotípicos foram pequenos, sugerindo necessidade de melhorias genéticas e ambientais.(AU)

We compared two models (with or without maternal effect) in the estimation of genetic parameters through Bayes Factor (BF) and the Deviance Information Criterion (DIC). Additionally, we evaluated the genetic, maternal and phenotypic trends in Tabapuã bovine growth characteristics in the state of Bahia. The model that included the maternal effect provided smaller BF values (167,629.2; 117,341.2 and 124,804.8) and DIC (174,550.0; 120,242.7 and 128,037.2) for weights at 205 (W205), 365 (W365) and 550 (W550) days of age, respectively. The average estimates, a posteriori, the direct and maternal heritability (0.33, 0.43 and 0.44) and (0.15, 0.14 and 0.16) for the three characteristics, respectively. Genetic trends for direct effect were 0.4415 and 0.3613kg/year for W205 and W365 and presented increases of 0.25 and 0.15% in the average characteristics of the year. The phenotypic trend for W205 was 0.7039kg/year. Maternal genetic trends for the three characteristics showed losses and indicate absence of selection matrices for good maternal ability. Despite the magnitude of the estimated direct and maternal heritability, they indicate genetic gain opportunities, genetic and phenotypic trends indicated few direct gains and no gains for maternal ability.(AU)