Relationship of semen quality to inbreeding and gait of Colombian Creole horses / Relação da qualidade do sêmen com endogamia e marcha de cavalos crioulos colombianos

ABSTRACT: High consanguinity among equines has negative effects on semen quality, thus resulting in low motility and high levels of abnormality in the spermatozoa. However, such a relationship has not been studied in Colombian Creole horses, which have been subjected to particular selection practices focusing mainly on their gait. This research assessed the relationship of semen quality to inbreeding and gait of Colombian Creole horses. Semen was collected from 50 horses using the artificial vagina method. Sperm motility and kinematics were assessed with a computerized analysis system (SCA®). Sperm vitality (SV) and abnormal morphology (AM) were assessed via the eosin-nigrosin staining test. Functional membrane integrity (FMI) was assessed via the hypo-osmotic swelling test (HOST). Genealogies and consanguinity analysis was conducted using the Breeders Assistant for Horses program. An average of 3.6 ± 0.4 % was reported for the inbreeding coefficient (Ft). A decrease in sperm motility and kinematics was reported, which was associated with an increase in consanguinity (P < 0.05). Furthermore, differences in consanguinity were found based on gait. Similarly, a relationship between horse gait and semen quality (P < 0.05) was found. Authors concluded that semen quality of Colombian Creole horses has been affected by inbreeding and its relationship with genetic selection based on gait.

RESUMO: A alta consanguinidade entre equinos tem efeitos negativos na qualidade do sêmen, resultando em baixa motilidade e altos níveis de anormalidade nos espermatozóides. No entanto, tal relação não foi estudada em cavalos crioulos colombianos, que tem sido submetidos a práticas de seleção específicas com foco principalmente em sua marcha. O objetivo desta pesquisa foi avaliar o relação da qualidade do sêmen com endogamia e marcha de cavalos crioulos colombianos. O sêmen foi coletado de 50 cavalos pelo método da vagina artificial. A motilidade e a cinética dos espermatozoides foram avaliadas com um sistema de análise computadorizado (SCA®). A vitalidade do esperma (VE) e a morfologia anormal (MA) foram avaliadas por meio do teste de coloração com eosina-nigrosina. A integridade funcional da membrana (IFM) foi avaliada por meio do test hipo-osmótico (HOST). A análise de genealogias e consanguinidade foi conduzida usando o programa Breeders Assistant for Horses. Uma média de 3,6 ± 0,4% foi encontrada para o coeficiente de endogamia (Ft). Uma diminuição na motilidade e cinética dos espermatozoides, que foi associada a um aumento na consanguinidade (P < 0,05). Além disso, diferenças na consanguinidade foram encontradas com base na marcha. Da mesma forma, foi encontrada uma relação entre a marcha do cavalo e a qualidade do sêmen (P < 0,05). Os autores concluíram que a qualidade do sêmen de cavalos crioulos colombianos foi afetada pela endogamia e sua relação com a seleção genética baseada na marcha.

Relationship of semen quality to inbreeding and gait of Colombian Creole horses / Relação da qualidade do sêmen com endogamia e marcha de cavalos crioulos colombianos

High consanguinity among equines has negative effects on semen quality, thus resulting in low motility and high levels of abnormality in the spermatozoa. However, such a relationship has not been studied in Colombian Creole horses, which have been subjected to particular selection practices focusing mainly on their gait. This research assessed the relationship of semen quality to inbreeding and gait of Colombian Creole horses. Semen was collected from 50 horses using the artificial vagina method. Sperm motility and kinematics were assessed with a computerized analysis system (SCA®). Sperm vitality (SV) and abnormal morphology (AM) were assessed via the eosin-nigrosin staining test. Functional membrane integrity (FMI) was assessed via the hypo-osmotic swelling test (HOST). Genealogies and consanguinity analysis was conducted using the Breeders Assistant for Horses program. An average of 3.6 ± 0.4 % was reported for the inbreeding coefficient (Ft). A decrease in sperm motility and kinematics was reported, which was associated with an increase in consanguinity (P < 0.05). Furthermore, differences in consanguinity were found based on gait. Similarly, a relationship between horse gait and semen quality (P < 0.05) was found. Authors concluded that semen quality of Colombian Creole horses has been affected by inbreeding and its relationship with genetic selection based on gait.

A alta consanguinidade entre equinos tem efeitos negativos na qualidade do sêmen, resultando em baixa motilidade e altos níveis de anormalidade nos espermatozóides. No entanto, tal relação não foi estudada em cavalos crioulos colombianos, que tem sido submetidos a práticas de seleção específicas com foco principalmente em sua marcha. O objetivo desta pesquisa foi avaliar o relação da qualidade do sêmen com endogamia e marcha de cavalos crioulos colombianos. O sêmen foi coletado de 50 cavalos pelo método da vagina artificial. A motilidade e a cinética dos espermatozoides foram avaliadas com um sistema de análise computadorizado (SCA®). A vitalidade do esperma (VE) e a morfologia anormal (MA) foram avaliadas por meio do teste de coloração com eosina-nigrosina. A integridade funcional da membrana (IFM) foi avaliada por meio do test hipo-osmótico (HOST). A análise de genealogias e consanguinidade foi conduzida usando o programa Breeders Assistant for Horses. Uma média de 3,6 ± 0,4% foi encontrada para o coeficiente de endogamia (Ft). Uma diminuição na motilidade e cinética dos espermatozoides, que foi associada a um aumento na consanguinidade (P < 0,05). Além disso, diferenças na consanguinidade foram encontradas com base na marcha. Da mesma forma, foi encontrada uma relação entre a marcha do cavalo e a qualidade do sêmen (P < 0,05). Os autores concluíram que a qualidade do sêmen de cavalos crioulos colombianos foi afetada pela endogamia e sua relação com a seleção genética baseada na marcha.

Genetic parameters and trends for reproductive traits in Blanco Orejinegro cattle from Colombia / Parâmetros e tendências genéticas para características reprodutivas no gado Blanco Orejinegro da Colômbia

The Colombian creole cattle breed Blanco Orejinegro (BON) is an important zoogenetic resource, but there is little knowledge about the genetic parameters and trends of its reproductive traits. Therefore, the aim of this study was to estimate parameters for the reproductive traits calving interval (CI), age at first calving (AFC), gestation duration (GD) and genetic trends for CI in the BON breed. Genealogy information from 7,799 animals was used, and employing the MTDFREML program, the components of the variance, heritability (h2), repeatability (rep), and estimated breeding values (EBV) for CI (n=3308), AFC (n=729), and GD (n=306) were estimated, in addition to the inbreeding coefficient (F) of the population. Genetic trends were established through linear regression using R software. Finally, the animals were classified as inbred (F > 0) and noninbred (F=0), and the effect of inbreeding on reproductive performance was established through a generalized linear model using the R program. An average F value of 4.41%±0.06 was observed. The h2 for CI was 0.11±0.03 with a rep of 0.15±0.04; for AFC, h2 was 0.00±0.05; and for GD, h2 was 0.00±0.08. The genetic trend for CI was -0.01 days/year. Finally, for CI, inbreeding depression was evident; this trait increased when inbreeding increased. These results indicate an important environmental influence on reproductive traits. The heritability estimate for CI suggests that little genetic progress could be achieved through selection. The evidence of inbreeding depression raises the need to control inbreeding to conserve this genetic resource.(AU)

O gado crioulo colombiano Blanco Orejinegro (BON) é um importante recurso zoogenético, mas ainda há desconhecimento sobre os parâmetros e tendências genéticas das características reprodutivas dessa raça. Portanto, o objetivo deste estúdio foi estimar parâmetros e tendências genéticas para características reprodutivas intervalo de partos (IDP), idade ao primeiro parto (IPP) e duração da gestação (DG) na raça BON. A informação da genealogia de 7,799 animais foi usada. Utilizando o programa MTDFREML foram estimados os componentes de variância, herdabilidade (h2), repetibilidade (rep) e valores genéticos (VGE), para IDP (n=3308), IPP (n=729) e DG (n=306), além do coeficiente de endogamia (F) na população. As tendências genéticas foram determinadas por regressão linear usando o software R. Finalmente, os animais foram classificados como endogâmicos (F > 0) e não endogâmicos (F=0) e o efeito da endogamia no desempenho reprodutivo foi determinado usando um modelo linear generalizado usando R. Observouse um F médio de 4,41%+0,06. A h2 para IDP foi 0,11±0,03 com uma repetibilidade de 0,15±0,04; para IPP a h2 foi 0,00 ± 0,05; e para DG a h2 foi 0,00 ± 0,08. A tendência genética para IDP foi -0,01 dias/ano. Finalmente, para o IDP, a depressão por endogamia foi evidente, aumentando o IDP com o aumento da endogamia. Os resultados indicam uma importante influência ambiental nas características reprodutivas. A herdabilidade estimada para o IDP sugere que pouco ganho genético pode ser alcançado através da seleção, embora a depressão endogâmica evidencie a necessidade de controlar a consanguinidade para conservar o recurso genético.(AU)

Amelia de membros torácicos em potro árabe: relato de caso / Amelia thoracic limbs in Arabian foal: case report / Amelia de miembros torácicos en potro árabe: caso clínico

Amelia é uma alteração congênita em que um ou mais membros anteriores estão ausentes, em parte ou totalmente. O presente relato de caso descreve a ocorrência de um caso de amelia bilateral dos membros torácicos de uma potranca, da raça Árabe, oriunda de uma gestação, cujos pais, possuíam grau de consanguinidade de 25%. O diagnóstico foi realizado pela inspeção, exame físico e radiológico, onde foi observada ausência dos ossos distais ao úmero no membro torácico direito e no membro torácico esquerdo havia um pequeno fragmento da diáfise e epífise do rádio e ulna.

Amelia is a congenital condition in which one or more forelimbs are missing, either in part or totally. This case report describes the occurrence of a case of bilateral amelia of the forelimbs of an Arabian foal, coming from a pregnancy, whose parents had a degree of consanguinity of 25%. The diagnosis was made by inspection, physical examination and radiology, where it was observed the absence of the distal humerus bone in the right forelimb and the left forelimb was a small fragment of the diaphysis and epiphysis of the radius and ulna.

Amelia es una alteración congénita de un o más miembros anteriores siendo ausentes en parte o totalmente. Este caso describe la ocurrencia de un caso de amelia bilateral de las extremidades delanteras de una potra, de raza árabe, procedente de un embarazo, donde los padres tenían un grado de consanguinidad de un 25%. El diagnóstico se realizó mediante la inspeción, examen fisico, la disección y la radiología, donde se observó la ausencia de los huesos distales al húmero en miembro superior derecho y miembro torácico izquierdo había un pequeño fragmento de la diáfisis y epífisis del radio y el cúbito.

Condrodisplasia tipo Dexter em fetos bovinos abortados / Chondrodysplasia Dexter type in aborted bovine fetuses

Background: Chondrodysplasia is a congenital anomaly related to defects of the genes that control the chondrogenesis. This anomaly is described in many breeds of cattle and consanguineous matings increases the likelihood of developing defective traits. There are three distinct syndromes known: Dexter, Telemark and Brachycephalic type. The chondrodysplasia Dexter type syndrome is associated to an incompletely dominant gene, which occurs in Dexter and Holstein breeds more frequently, yet Charolais and Jersey can also be affected. There are three recognized phenotypes in this form of disease: severe achondroplasia, with abortion before the seventh month of gestation (monster Dexter), when related to dominant homozygous; chondrodisplasia with limbs shortening, when heterozygous; and normal animals, when recessive homozygous. The objective of this paper is to describe Dexter chondrodysplasia observed in two bovine fetuses examined by the Setor de Patologia Veterinária from Universidade Federal do Rio Grande do Sul (SPV-UFRGS). Case: The necropsy of two aborted bovine calves was performed by the SPV-UFRGS. The Fetus 1 did not have data, neither clinical history. The Fetus 2, a Jersey breed calf, was in the last third of gestation and came from a property with Jersey and mini-Jersey herd. Natural mating was used for reproduction, with only one bull. Macroscopic alterations observed in both fetuses were characterized by shortened limbs, rounded and disproportionate skull, short snout, undershot jaw, tongue protrusion and abdominal hernia with eventration. In the second fetus was also observed spina bifida and palatoschisis. Microscopically, in both fetuses were observed extensive areas of immature cartilage, chondrocytes of the femur's bone tissue were not organized in recognizable growth plates, the metaphysis was markedly shortened and consisted in short bone trabeculae with occasional cartilage isles. Immunohistochemistry (IHC) to detect bovine viral diarrhea virus (BVDV) was negative. Discussion: The macroscopic and microscopic alterations in both fetuses were compatible with chondrodysplasia "monster Dexter" type. Such alterations, associated with dominant homozygotes, are due to defective endochondral ossifi cation with little growth in the length of long bones, meanwhile intramembranous ossification beneath the periosteum keeps growing and contributing to the abnormal volume and growth of the bones. Such difference is clearly observed when the size of the head is compared with the rest of the body. As the skull bones depends basically on intramembranous ossification, they are generally bigger than the rest of the body. The negative result of IHC to BVDV shows that this agent, known as the cause of congenital malformation did not have association with the anomalies observed. According to other researchers, this low frequency of viral agents as responsible for congenital anomalies was observed previously in cattle from the south of Brazil. Although Dexter chondrodysplasia can be considered of occasional occurrence, it can be responsible for considerable damage. As an abnormality with hereditary nature and consanguinity is the main reason to its occurrence, prevention is the main method to be adopted by the producer to avoid bigger loses.

Chondrodysplasia dexter type in aborted bovine fetuses / Condrodisplasia tipo Dexter em fetos bovinos abortados

Background: Chondrodysplasia is a congenital anomaly related to defects of the genes that control the chondrogenesis. This anomaly is described in many breeds of cattle and consanguineous matings increases the likelihood of developing defective traits. There are three distinct syndromes known: Dexter, Telemark and Brachycephalic type. The chondrodysplasia Dexter type syndrome is associated to an incompletely dominant gene, which occurs in Dexter and Holstein breeds more frequently, yet Charolais and Jersey can also be affected. There are three recognized phenotypes in this form of disease: severe achondroplasia, with abortion before the seventh month of gestation (monster Dexter), when related to dominant homozygous; chondrodisplasia with limbs shortening, when heterozygous; and normal animals, when recessive homozygous. The objective of this paper is to describe Dexter chondrodysplasia observed in two bovine fetuses examined by the Setor de Patologia Veterinária from Universidade Federal do Rio Grande do Sul (SPV-UFRGS).Case: The necropsy of two aborted bovine calves was performed by the SPV-UFRGS. The Fetus 1 did not have data, neither clinical history. The Fetus 2, a Jersey breed calf, was in the last third of gestation and came from a property with Jersey and mini-Jersey herd. Natural mating was used for reproduction, with only one bull. Macroscopic alterations observed in

Background: Chondrodysplasia is a congenital anomaly related to defects of the genes that control the chondrogenesis. This anomaly is described in many breeds of cattle and consanguineous matings increases the likelihood of developing defective traits. There are three distinct syndromes known: Dexter, Telemark and Brachycephalic type. The chondrodysplasia Dexter type syndrome is associated to an incompletely dominant gene, which occurs in Dexter and Holstein breeds more frequently, yet Charolais and Jersey can also be affected. There are three recognized phenotypes in this form of disease: severe achondroplasia, with abortion before the seventh month of gestation (monster Dexter), when related to dominant homozygous; chondrodisplasia with limbs shortening, when heterozygous; and normal animals, when recessive homozygous. The objective of this paper is to describe Dexter chondrodysplasia observed in two bovine fetuses examined by the Setor de Patologia Veterinária from Universidade Federal do Rio Grande do Sul (SPV-UFRGS).Case: The necropsy of two aborted bovine calves was performed by the SPV-UFRGS. The Fetus 1 did not have data, neither clinical history. The Fetus 2, a Jersey breed calf, was in the last third of gestation and came from a property with Jersey and mini-Jersey herd. Natural mating was used for reproduction, with only one bull. Macroscopic alterations observed in

Efeito da endogamia sobre características morfométricas em cavalosda raça Mangalarga Marchador / Effect of inbreeding on morfhometric traits in Mangalarga Marchador horses

Estimou-se o coeficiente de endogamia e avaliou-se seu efeito sobre características morfométricas dos animais em um criatório no norte de Minas Gerais. As características estudadas foram alturas da cernelha e da garupa, comprimentos da cabeça, do pescoço, do dorso-lombo, da garupa e do corpo, larguras do peito e da garupa. O arquivo continha 2186 informações de parentesco de animais do arquivo zootécnico da fazenda, desde o início da formação da raça, 1951, até o ano de 2006. Calculou-se o coeficiente de endogamia (F) e avaliou-se seu efeito por meio de regressão linear simples sobre as medidas morfométricas. Do total de animais, 27,6% mostraram-se endogâmicos, sendo o F médio da população igual a 1,4%. Considerando-se apenas os animais endogâmicos, a consanguinidade média atingiu 5,3%, mínimo de 0,1 e máximo de 28,1%. Não se verificaram efeitos negativos da endogamia sobre as características morfométricas, exceto para largura da garupa, em que se observou que para cada 10% de acréscimo de F houve aumento de 0,576cm na largura da garupa. Possivelmente, devido ao baixo valor encontrado, a endogamia não influenciou as demais características avaliadas.(AU)

The coefficient of inbreeding was estimate and its effect on linear traits of the Mangalarga Marchador horses reared in a ranch in the North of Minas Gerais was evaluated. The characteristics studied were morphometric traits such as wither and hip height, length of head, neck, back-loin, hip and body, as well as chest and hip width. The archive had 2186 data on the genealogy of animals from the herd register of the Catuni Farm. The coefficient of inbreeding (F) was calculated and its effect was evaluated by means of simple linear regression on the linear traits. Of all animals, 27.6% showed inbreeding, with an F average of 1.4% in the population. Considering only the inbred animals, the average consanguinity reached 5.3% minimum of 0.1 and maximum of 28.1%. Negative effects of inbreeding on the morphometric traits were not seen, except for hip width, where for each 10% increase in F there was increase of 0.576cm. Possibly due to the low value found, inbreeding did not influence the other evaluated characteristics.(AU)

ESTRUTURA POPULACIONAL E ANÁLISE DE VARIABILIDADE GENÉTICA EM REBANHOS OVINOS BRASILEIROS

As raças ovinas deslanadas são parte do patrimônio genético do Brasil, formado por animais adaptados ao semiárido nordestino e com potencial de produção de carne e pele. No entanto tratam-se de raças de recente formação, ainda com poucos programas de melhoramento genético, e consequentemente, carente de estudos da estrutura populacional, variabilidade genética, endogamia e grau de conservação. Diante disso este trabalho teve dois objetivos: 1) analisar a variabilidade genética da raça Santa Inês no Brasil com base em informações de pedigree utilizando registros de animais da raça Santa Inês, provenientes da Associação Sergipana de Criadores de Caprinos e Ovinos (ASCCO) criados na Região Nordeste do Brasil e 2) avaliar a estrutura genética e variabilidade genética do núcleo de conservação da Embrapa Caprinos e Ovinos, localizada na cidade de Sobral, região do norte do estado do Ceará, controlado pelo Sistema de Gerenciamento de rebanho (SGR) dentro do dentro do programa de melhoramento genético de caprinos e ovinos de corte GENECOC®. O arquivo de pedigree da raça Santa Inês (ASCCO) continha 29080 animais e os arquivos de dados genealógicos pertencentes ao GENECOC 904 indivíduos da raça Santa Inês, 972 indivíduos da raça Somalis e 1372 indivíduos da raça Morada Nova. Para a primeira análise dos animais Santa Inês a média da integridade do pedigree nas últimas quatro gerações foi maior que 50% e o número de gerações completas equivalente foi igual a 4,89. O valor do coeficiente endogâmico (F) foi de 0,32% e o coeficiente de parentesco obtido foi de 3,1%. O intervalo de geração foi de 5,75 anos. Os resultados dos parâmetros com base na probabilidade de origem do gene: número de fundadores (Nf), número efetivo de fundadores (fe), número efetivo de ancestrais (fa) e número efetivo de genomas remanescentes (fg) foram: (Nf) > (fe) > (fa) > (fg). A razão (fe)/ (fa) foi próxima de 1, indicando que não houve gargalo genético, já a razão (fg)/ (fe) foi de 0,30 e mais distante de 1, indica um processo rápido de deriva genética, pois quantifica a perda de alelos fundadores entre gerações. Enquanto que para os indivíduos Santa Inês, Somalis e Morada Nova o coeficiente de parentesco médio (AR) foram de 5,17%, 4,98% e 4,98 e consanguinidade (F) foram de 1,81%, 0,78% e 0,78 respectivamente. O intervalo de gerações (IEG) foi de 3,54, 3,40 e 4,08 anos e o tamanho efetivo médio (Ne) por geração foi de 30, 15 e 35 animais, sendo que o número efetivo de animais fundadores ( fe ) de 29,54, 38,60 e 29,43 e de ancestrais ( fa ) foi igual a (17, 13 e 19 respectivamente). Dentre os ancestrais, apenas 7 Santa Inês, 5 Somalis e 10 Morada Nova foram responsáveis por 50% da variabilidade genética das populações, o que indica perda de genes de origem. Concluindo-se que na população de ovinos da raça Santa Inês (ASCCO) a variabilidade genética permitirá a obtenção de ganhos genéticos adequados nas características de importância econômica. Enquanto que nas populações de conservação do GENECOC observa-se baixa contribuição dos animais fundadores ao longo das gerações. Os valores do coeficiente de endogamia de Wright indicam subdivisão da população em linhagens. Em geral, a consanguinidade e os valores médios do coeficiente de parentesco foram baixos e a variabilidade genética foi considera alta.

The wooless sheep breeds are part of the genetic heritage of Brazil, formed by animals highly adapted to semi-arid Northeast and high capacity of production of meat and skin. However it is of recent formation breeds, still few breeding programs, and consequently lacking in studies of population structure, genetic variability, inbreeding and degree of conservation. Therefore this study had two objectives: 1) to analyze the genetic variability of Santa Ines in Brazil based on pedigree information using animal records Santa Ines, from the Goat Breeders of Sergipana Association and Sheep (ASCCO) created in Northeast of Brazil and 2) evaluate the genetic structure and genetic variability conservation nucleus of Embrapa goats and sheep, located in Sobral, northern region of the state of Ceará, compiled by Management System for Livestock, part of the within the Breeding Program of Goats and sheep - GENECOC®. Santa Inês breed pedigree file (ASCCO) contained 29080 animals and genealogical data files belonging to GENECOC 904 individuals Santa Ines, 972 individuals of Somalis breed and 1372 individuals of Morada Nova breed. For the first analysis of animal Santa Inês the average pedigree integrity in the last four generations was greater than 50% and the number of full generations equivalent was equal to 4.89. The value of endogamic coefficient (F) was 0.32% and the obtained relationship coefficient was 3.1%. The generation interval was 5.75 years. For the results of the parameters based on the probability of gene origin: number of founders (Nf), effective number of founders (fe), effective number of ancestors (fa) and effective number of remaining genomes (fg): (Nf)> (fe)> (fa)> (fg). The ratio (fg) / (fa) was close to 1, indicating no genetic bottleneck, as the ratio (fg) / (fe) was 0.30 and more distant from 1, indicating a rapid process of genetic drift, it quantifies the loss of founder alleles between generations. While for individuals Santa Inês, Morada Nova Somalis and the average relatedness coefficient (AR) were 5.17%, 4.98% and 4.98% and inbreeding (F) were 1.81%, 0.78 and 0.78% respectively. The generation interval (IEG) was 3.54, 3.40 and 4.08 years and the mean effective size (Ne) per generation was 30, 15 and 35 animals, with the effective number of founder animals (fe) of 29.54, 38.60 and 29.43 and ancestors (fa) is equal to (17, 13 and 19 respectively). Among the ancestors, only 7 Santa Ines, 5 Somalis and 10 Morada Nova accounted for 50% of the genetic variability of populations, indicating loss of original genes. Concluding that the population of sheep Santa Inês (ASCCO) genetic variability will allow obtaining appropriate genetic gains in traits of economic importance. While in GENECOC conservation populations observed low contribution of animal founders over the generations. The values of Wright's inbreeding coefficient indicates subdivision of the population lineages. In general, inbreeding and the mean values of inbreeding coefficient were low and the genetic variability considered high.

Chondrodysplasia dexter type in aborted bovine fetuses / Condrodisplasia tipo Dexter em fetos bovinos abortados

Background: Chondrodysplasia is a congenital anomaly related to defects of the genes that control the chondrogenesis. This anomaly is described in many breeds of cattle and consanguineous matings increases the likelihood of developing defective traits. There are three distinct syndromes known: Dexter, Telemark and Brachycephalic type. The chondrodysplasia Dexter type syndrome is associated to an incompletely dominant gene, which occurs in Dexter and Holstein breeds more frequently, yet Charolais and Jersey can also be affected. There are three recognized phenotypes in this form of disease: severe achondroplasia, with abortion before the seventh month of gestation (monster Dexter), when related to dominant homozygous; chondrodisplasia with limbs shortening, when heterozygous; and normal animals, when recessive homozygous. The objective of this paper is to describe Dexter chondrodysplasia observed in two bovine fetuses examined by the Setor de Patologia Veterinária from Universidade Federal do Rio Grande do Sul (SPV-UFRGS).Case: The necropsy of two aborted bovine calves was performed by the SPV-UFRGS. The Fetus 1 did not have data, neither clinical history. The Fetus 2, a Jersey breed calf, was in the last third of gestation and came from a property with Jersey and mini-Jersey herd. Natural mating was used for reproduction, with only one bull. Macroscopic alterations observed in

Background: Chondrodysplasia is a congenital anomaly related to defects of the genes that control the chondrogenesis. This anomaly is described in many breeds of cattle and consanguineous matings increases the likelihood of developing defective traits. There are three distinct syndromes known: Dexter, Telemark and Brachycephalic type. The chondrodysplasia Dexter type syndrome is associated to an incompletely dominant gene, which occurs in Dexter and Holstein breeds more frequently, yet Charolais and Jersey can also be affected. There are three recognized phenotypes in this form of disease: severe achondroplasia, with abortion before the seventh month of gestation (monster Dexter), when related to dominant homozygous; chondrodisplasia with limbs shortening, when heterozygous; and normal animals, when recessive homozygous. The objective of this paper is to describe Dexter chondrodysplasia observed in two bovine fetuses examined by the Setor de Patologia Veterinária from Universidade Federal do Rio Grande do Sul (SPV-UFRGS).Case: The necropsy of two aborted bovine calves was performed by the SPV-UFRGS. The Fetus 1 did not have data, neither clinical history. The Fetus 2, a Jersey breed calf, was in the last third of gestation and came from a property with Jersey and mini-Jersey herd. Natural mating was used for reproduction, with only one bull. Macroscopic alterations observed in