RESUMO -Objetivou-se, com este trabalho, avaliar as relações entre medidas lineares de eqüinos em crescimento, do nascimento aos doze meses, e de animais adultos da raça Mangalarga Marchador. As medidas utilizadas foram peso corporal e medidas de altura, de comprimento, de largura e de perímetro dos animais. Morphometric Evaluation of Mangalarga Marchador Horse: Conformation Index and Body ProportionsABSTRACT -This work aims to evaluate the relationships between body measures of foals from birth to twelve months of age and mature animals of Mangalarga Marchador breed. Measures were body weight and measures of height, length, width, girth of animals. Corporal Index (CI), Meloscopic Index (MI), Dactilo-thoracic Index (DTI) and Weigth in Cannon Index (WCI) were used to evaluate the relationship between measures. The Eclectic System of Linear Proportions was used to evaluation the proportions between linear measures and head length. Colts and fillies were classified as small shape at birth, because the CI were 81.36 and 82.33, respectively. Colts and fillies with four months of age, already presented CI higher than 85.0, and were classified as medium shape. Stallions and mares were classified as medium shape, with CI of 87.17 and 85.18, respectively. Considering the MI, colts and fillies were classified as large shape at birth, changing to medium shape with increase of age and stallions and mares were classified as medium shape. The DTI classified the colts and fillies as hipermetric animals because presented values above 10.8. The WCI ranged from 26.18 to 6.60 for fillies and from 25.93 to 7.04 for colts, while for stallions and mares were 4.16 and 4.96, respectively. Linear measures with greater rates of growth than the head length presented increase of the proportions from birth to adult age, while the measures of smaller rates of growth than the head length presented reverse behavior.

RESUMO -Objetivou-se com o presente trabalho avaliar o crescimento de potros da raça Mangalarga Marchador por meio de suas medidas lineares. Foram mensurados 98 potros, sendo 55 machos e 43 fêmeas, ao nascimento e a cada 30 dias até completarem 12 meses de idade. Os pais e as mães dos potros foram mensurados para obtenção dos valores médios das medidas lineares estudadas nos animais adultos. Os valores das medidas corporais dos animais foram submetidos à análise de variância e o modelo estatístico incluiu os efeitos de sexo, local, manejo nutricional, rebanho, mês e ano de nascimento. As características de conformação estudadas não foram influenciadas pelos efeitos de sexo, rebanho, região, manejo nutricional, mês e ano de nascimento. A medida de altura na cernelha apresentou reduzida variação, passando de 61,6% da média à idade adulta, ao nascimento, para 88% da média à idade adulta, aos 12 meses, nos machos, e de 63,2% da média à idade adulta, ao nascimento, para 90% da média à idade adulta, aos 12 meses, nas fêmeas. De forma similar, a altura na garupa passou de 63,3% da média à idade adulta, ao nascimento, para 89% da média à idade adulta, aos 12 meses, nos machos e de 64,1% da média à idade adulta, ao nascimento, para 91,1% da média à idade adulta, aos 12 meses, nas fêmeas. O comprimento do corpo dos potros apresentou valores de 68,1; 112,6 e 127,1 cm nos machos e de 68; 111,6 e 128,3 cm nas fêmeas, ao nascimento, 6 e 12 meses, respectivamente. Em relação à idade adulta, os valores observados para comprimento do corpo foram 43,3; 71,6 e 86,6%, nos machos, e 45,5; 74,7 e 85,8%, nas fêmeas, ao nascimento, 6 e 12 meses de idade, respectivamente. Palavras-chave: crescimento, mensuração, potros Morphometric Evaluation of Mangalarga Marchador Horses: Linear MeasuresABSTRACT -The present work aimed to evaluate foals growth of the Mangalarga Marchador breed, by linear measures. Ninetyeight foals, 55 males and 43 females were measured at birth and at each 30 days up to 12 months age. Results of body measures were submitted to analysis of variance and statistical model includes effects of sex, local, nutritional management, herd, month and year of birth. Conformation characteristics studied were not influenced by the effects of sex, herd, nutritional management, month and year of birth. In relation to height in the withers and in the hip measures, it was observed small variation, from 61.6 and 63.3% of mature age, at birth, from 88 to 89% of mature age, at 12 th month of age, for males and from 63.2 and 64.1% of mature age, at birth, from 90.0 to 91.1% of mature age, at 12 th month of age, for females. Values of body length of foals were of 68.1, 112.6 and 127.1 cm for males and 68.0, 111.6 and 128.3 cm, for females, at birth, 6 th month and 12 th month of age, respectively. In relation to mature age, the observed values of body length were 43.3, 71.6 and 86.6%, for males and 45.5, 74.7 and 85.8%, for females, at birth, 6 th month and 12 th month of age, respectively.

BackgroundDespite the health concerns and nutritional importance of fatty acids, there is a relative paucity of studies in the literature that report genetic or genomic parameters, especially in the case of sheep populations. To investigate the genetic architecture of fatty acid composition of sheep, we conducted genome-wide association studies (GWAS) and estimated genomic heritabilities for fatty acid profile in Longissimus dorsi muscle of 216 male sheep.ResultsGenomic heritability estimates for fatty acid content ranged from 0.25 to 0.46, indicating that substantial genetic variation exists for the evaluated traits. Therefore, it is possible to alter fatty acid profiles through selection. Twenty-seven genomic regions of 10 adjacent SNPs associated with fatty acids composition were identified on chromosomes 1, 2, 3, 5, 8, 12, 14, 15, 16, 17, and 18, each explaining ≥0.30% of the additive genetic variance. Twenty-three genes supporting the understanding of genetic mechanisms of fat composition in sheep were identified in these regions, such as DGAT2, TRHDE, TPH2, ME1, C6, C7, UBE3D, PARP14, and MRPS30.ConclusionsEstimates of genomic heritabilities and elucidating important genomic regions can contribute to a better understanding of the genetic control of fatty acid deposition and improve the selection strategies to enhance meat quality and health attributes.

Background A decline in the level of genetic diversity in livestock can result in reduced response to selection, greater incidence of genetic defects, and inbreeding depression. In this context, various metrics have been proposed to assess the level of genetic diversity in selected populations. Therefore, the main goals of this study were to: 1) investigate the population structure of 16 cattle populations from 15 different pure breeds or composite populations, which have been selected for different breeds goals; and, 2) identify and compare runs of homozygosity (ROH) and heterozygosity-enriched regions (HER) based on different single nucleotide polymorphism (SNP) panels and whole-genome sequence data (WGS), followed by functional genomic analyses. Results A total of 24,187 ROH were found across all cattle populations, with 55% classified in the 2-4 Mb size group. Fourteen homozygosity islands were found in five populations, where four ROH islands located on BTA1, BTA5, BTA16, and BTA19 overlapped between the Brahman (BRM) and Gyr (GIR) breeds. A functional analysis of the genes found in these islands revealed candidate genes known to play a role in the melanogenesis, prolactin signaling, and calcium signaling pathways. The correlations between inbreeding metrics ranged from 0.02 to 0.95, where the methods based on homozygous genotypes (FHOM), uniting of gametes (FUNI), and genotype additive variance (FGRM) showed strong correlations among them. All methods yielded low to moderate correlations with the inbreeding coefficients based on runs of homozygosity (FROH). For the HER, 3576 runs and 26 islands, distributed across all autosomal chromosomes, were found in regions containing genes mainly related to the immune system, indicating potential balancing selection. Although the analyses with WGS did not enable detection of the same island patterns, it unraveled novel regions not captured when using SNP panel data. Conclusions The cattle populations that showed the largest amount of ROH and HER were Senepol (SEN) and Montana (MON), respectively. Overlapping ROH islands were identified between GIR and BRM breeds, indicating a possible historical connection between the populations. The distribution and pattern of ROH and HER are population specific, indicating that different breeds have experienced divergent selection processes or different genetic processes.

RESUMO -Objetivou-se, com este trabalho, avaliar a produção e a composição do leite de éguas Mangalarga Marchador e o ganho de peso dos potros lactentes. A produção de leite foi avaliada em oito éguas, pelo método da pesagem dos potros antes e depois das mamadas, em intervalos de duas horas, em doze observações diárias. A partir do somatório da quantidade de leite produzido nas observações, obteve-se a produção diária de leite. A produção de leite, analisado quanto aos teores de lactose, proteína, gordura e energia, foi avaliada aos 20, 40, 60, 80, 100, 120, 140 e 160 dias da lactação A produção média de leite variou de 9,95 kg/dia no 40 o dia a 7,48 kg/dia no final da lactação. A produção total de leite estimada foi igual a 1405,56 kg. A produção de leite, expressa em percentual do peso vivo (PV) das éguas, variou entre 2,3% do PV no 20 o dia e 1,8% do PV no final da lactação, sendo similar às quantidades de leite produzidas nos períodos diurno e noturno. Não foi observado efeito da idade das éguas na produção de leite. O ganho médio diário de peso dos potros ao longo do período de amamentação foi de 0,77 kg, com maiores valores nos meses iniciais do período de amamentação. O leite das éguas apresentou baixas concentrações de proteína, gordura e energia e altas de lactose, além de resposta quadrática decrescente, em função do período da lactação. Palavras-chave: lactação, eqüinos, exigências nutricionais Lactation in Mangalarga Marchador Mares: Yield production and Composition of Milk, and Weight Gain of Suckling FoalsABSTRACT -This work aims to evaluate yield production and composition of milk of Mangalarga Marchador mares and average weight gain of suckling foals. Milk yield was evaluated in eight mares by the weigh-suck-weigh method, at intervals of two hour, twelve times a day. Daily milk produced was estimated by summing of the twelve observations. Milk yield was performed at 20, 40, 60, 80, 100, 120, 140 and 160 days of lactation. The milk was analyzed for lactose, protein, fat and energy concentration. Daily milk production ranged from 9.95 kg at 40 th day to 7.48 kg no final da lactação (160 th day) Total estimate milk yield during the lactation was 1405.56 kg. Milk yield as a % LW of mares ranged from 2.3% LW at 20 th day to 1.8% LW at the end of lactation. Amounts of milk produced during daytime and nighttime was similar and mare age did not affect milk production. Average weight gain of foals during lactation period was 0.77 kg/day with higher values at first months of lactation period. Milk showed low concentration of protein, fat and energy, high levels of lactose, with a decreasing quadratic response in function of lactation period.

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For genomic selection to be successful, there must be sufficient linkage disequilibrium between the markers and the causal mutations. The objectives of this study were to evaluate the extent of LD in ovine using the Santa Inês breed and to infer the minimum number of markers required to reach reasonable prediction accuracy. In total, 38,168 SNPs and 395 samples were used. The mean LD between adjacent marker pairs measured by r2 and |D′| were 0.166 and 0.617, respectively. LD values between adjacent marker pairs ranged from 0.135 to 0.194 and from 0.568 to 0.650 for r2 for |D′| across all chromosomes. The average r2 between all pairwise SNPs on each chromosome was 0.018. SNPs separated by between 0.10 to 0.20 Mb had an estimated average r2 equal to 0.1033. The identified haplotype blocks consisted of 2 to 21 markers. Moreover, estimates of average coefficients of inbreeding and effective population size were 0.04 and 96, respectively. LD estimated in this study was lower than that reported in other species and was characterized by short haplotype blocks. Our results suggest that the use of a higher density SNP panel is recommended for the implementation of genomic selection in the Santa Inês breed.