ABSTRACT: Growth hormone (GH), insulin-like growth factor 1 (IGF1), and leptin (LEP) can be candidate genes for association studies because they play vital roles in the metabolism process. Thus, this study aimed to identify variants in these genes associated with body traits in Santa Inês sheep. The following were recorded: body weight at 100 (BW100) and 240 days (BW240), average daily gain (ADG), withers (WH) and croup (CH) heights, body length (BL), thoracic (TG) and leg (LG) girths, thoracic (TW) and croup (CW) widths, body depth (BD), rib eye area (REA), fat thickness (FT), and carcass finishing score (CFS). Single-locus association analysis was performed with 11 variants in IGF1, 18 in LEP, and 16 in GH. Moreover, two haplotypes in IGF1 and one haplotype in LEP were evaluated in haplotype association analysis. The single-locus analysis revealed 23 suggestive additive effects (p < 0.05), but no additive effect was found at the Bonferroni threshold. Haplotype association analysis revealed 19 additive effects, of which ten were at the Bonferroni threshold (p < 0.0074). In IGF1 gene, haplotype replacements were associated with ADG 20.51(7.37), CH 4.09(1.21), WH 3.52(1.20), BL 3.94(1.19), TG 3.88(1.30), TW 1.13(0.36), and LG 3.40(1.08); while in the LEP gene the haplotype replacement was associated with BW100 1.83(0.51), BD −2.51(0.56), and CFS −0.24(0.06). Therefore, there are haplotypes in IGF1 and LEP genes associated with body traits in Santa Inês sheep, which can be useful in marker-assisted selection.

ABSTRACT The present investigation aimed to evaluate the population structure and inbreeding of Holstein herds in southern Brazil. To carry out the analysis, the Associação Paranaense de Criadores de Bovinos da Raça Holandesa (APCBRH) in Brazil provided the data, which consisted of a pedigree file of 206,796 animals born between 1970 and 2014. Results regarding the following parameters were determined: pedigree integrity, effective number of founders, effective number of ancestors, generation interval, inbreeding coefficient, realized effective population size, and average relatedness coefficient. POPREP and ENDOG v.4.5 software packages were employed to estimate these parameters. Based on the data set, the mean generation interval was found to be 6.3 years, and the average inbreeding coefficient, related to inbred animals, was 4.99%. Furthermore, the realized effective population size varied throughout the time period, ranging from 22 to 114, whereas the rate of inbreeding in this same period showed a decreasing trend towards the later years in the period until 2014. Upon evaluation, average relatedness coefficient was estimated to be 0.71%. Moreover, the effective number of founders and ancestors were estimated as 418 and 400 animals, respectively. According to the level of inbreeding observed, it could be noticed that genetic diversity remains elevated, which will be important to the genetic progress in the Holstein breeding program in Southern Brazil.

Resumo: O objetivo deste trabalho foi sequenciar os genes MyoD1, MyoG, MyF5, MyF6 e MSTN e identificar polimorfismos em ovinos Santa Inês (Ovis aries). No total, 192 cordeiros com 240 dias de idade foram avaliados, e estes genes foram sequenciados para comparação com a sequência-referência no genoma de Ovis aries. As frequências genotípicas e alélicas foram estimadas, e o equilíbrio de Hardy-Weinberg, testado. Foram obtidos fragmentos contendo 2.493 pb (MyoDl), 1.836 pb (MyoG), 2.813 pb (MyF5), 1.126 pb (MyF6) e 2.380 pb (MSTN), e, nessas sequências, foram identificadas 160 variantes. Esses polimorfismos foram distribuídos da seguinte forma: 59 (MyoD1), 24 (MyoG), 63 (MyF5), 4 (MyF6) e 10 (MSTN). Foram encontrados 104 novos polimorfismos, sendo 45 no MyoD1, 2 no MyoG, 56 no MyF5 e 1 no MSTN. Com relação ao local, 61 variantes estavam em íntron (27 no MyoD1, 16 no MyoG, 5 no MyF5, 3 no MyF6 e 10 no MSTN), 87 em região codificante (22 no MyoD1, 8 no MyoG, 56 no MyF5 e 1 no MyF6) e 12 na região 3’UTR (10 no MyoD1 e 2 no MyF5). Portanto, os genes da família MyoD e o MSTN possuem vários polimorfismos em ovinos da raça Santa Inês, os quais podem ser úteis em estudos de associação.

Abstract: The objective of this work was to sequence the MyoD1, MyoG, MyF5, MyF6, and MSTN genes and to identify polymorphisms in Santa Inês sheep (Ovis aries). A total of 192 lambs with 240 days of age were evaluated, and these genes were sequenced to be compared with the reference sequence in the Ovis aries genome. Genotype and allele frequencies were estimated, and the Hardy-Weinberg equilibrium was tested. Fragments containing 2,493 bp (MyoD1), 1,836 bp (MyoG), 2,813 bp (MyF5), 1,126 bp (MyF6), and 2,380 bp (MSTN) were obtained, and, in these sequences, 160 variants were identified. These polymorphisms were distributed as follows: 59 (MyoD1), 24 (MyoG), 63 (MyF5), 4 (MyF6), and 10 (MSTN). One hundred and four were novel polymorphisms, 45 in MyoD1, 2 in MyoG, 56 in MyF5, and 1 in MSTN. Regarding site, 61 were in intron (27 in MyoD1, 16 in MyoG, 5 in MyF5, 3 in MyF6, and 10 in MSTN), 87 in coding region (22 in MyoD1, 8 in MyoG, 56 in MyF5, and 1 in MyF6), and 12 on 3’UTR (10 in MyoD1 and 2 in MyF5). Therefore, the MyoD family and MSTN genes have several polymorphisms in Santa Inês sheep, which can be useful for association studies.

ABSTRACT This study aimed to estimate the heritability of milk yield (MY), fat percent (F%), fat yield (FY), protein percent (P%), protein yield (PY), somatic cell score (SCS), and total bacterial count score (TBCS) as well as to estimate the genetic correlations among these traits, using a dataset from 5,918 lactations of Jersey cows in Brazil. The covariance components were estimated by restricted maximum likelihood using the PEST and VCE6 programs. The average values obtained for MY, F%, FY, P%, PY, SCS, and TBCS were 5017.5 kg, 4.3%, 192.3 kg, 3.3%, 173.0 kg, 5.9, and 2.9, respectively, while the heritability values were 0.16, 0.55, 0.18, 0.61, 0.25, 0.21, and 0.08, respectively. The genetic correlations ranged from low to high magnitude, with positive values from 0.06 (TBCS-PY) to 0.72 (FY-PY), and negative values from −0.04 (F%-TBCS) to −0.44 (P%-TBCS). The Jersey breed from Brazil shows genetic variability for all traits analyzed in the present study, and our results suggest that higher genetic gain will be achieved when F% and P% are used as selection criteria. In addition, it is important to use SCS as a selection criterion since the selection for MY and PY may lead to higher SCS or TBCS values, which are undesirable. This was the first study to estimate genetic parameters for milk quality (PY, P%, FY, F%) and udder health (SCS, TBCS) traits in Jersey cows from Brazil. This information is useful for breeding schemes and contributes to better characterize these parameters in tropical region, since few studies were developed with the Jersey cattle in this environment.

ABSTRACT This study aimed to estimate the heritability coefficients for ten functional type traits and milk production in the Jersey breed in Brazil, besides the genetic and phenotypic correlations between them. The present study utilised data from 1,567 records of linear type traits, including stature (ST), body depth (BD), loin strength (LS), rump width (RW), rump angle (RA), fore udder attachment (FUA), front teat placement (FTP), rear udder height (RUH), central ligament (CL), and final score (FS). Milk yield (MY) adjusted to 305 lactation days was also calculated. Covariance components were estimated by the restricted maximum likelihood approach using the PEST and VCE6 programs on the animal model. Heritability coefficients thus assessed were as follows: 0.22±0.01 (ST), 0.35±0.07 (BD), 0.17±0.01 (RW), 0.55±0.05 (RA), 0.09±0.01 (LS), 0.20±0.02 (FUA), 0.40±0.06 (FTP), 0.40±0.06 (RUH), 0.15±0.02 (CL), 0.21±0.02 (FS), and 0.16±0.02 (MY). Therefore, the higher genetic gain will be obtained for BD, RA, FTP, and RUH, while the other traits would need a medium or long-term period to show improvement. The genetic correlations fell in the range from 0.01 (FTP × FS) to 0.87 (RW × CL), and the only genetic correlation noted between FS and RA was negative (−0.10±0.06). Thus, in the Jersey breed in Brazil, the type traits are genetically associated, and the selection of any one of them may elicit an indirect response in another.

O objetivo com este trabalho foi avaliar os modelos não lineares que melhor descrevem a curva de crescimento de ovinos machos da raça Ile de France criados em confinamento no estado do Paraná. Para tanto, foram realizadas pesagens quinzenais no período de fevereiro de 2013 a junho de 2013, desde o nascimento até o abate (120 dias) de 31 machos da raça Ile de France. As curvas de crescimento foram obtidas pelos modelos não lineares de Brody, Von Bertalanffy, Gompertz e Logístico em que foram considerados os parâmetros da taxa de maturação (K), peso assintótico (A), idade do animal (t), constante de integração que determina a proporção de crescimento após nascimento (B) e proporção do valor assintótico em que ocorre o ponto de inflexão da curva (m), de acordo com o modelo adotado. Os parâmetros foram estimados pelo método Marquardt aplicado ao procedimento NLIN do programa estatístico SAS e os critérios utilizados para verificar a precisão do ajuste das curvas foram o quadrado médio do resíduo e o coeficiente de determinação. Os modelos Brody, Von Bertalanffy, Gompertz e Logístico resultaram respectivamente em 26,4579; 26,1668; 26,1360 e 26,1582 para o quadrado médio do resíduo e 0,8130; 0,9580; 0,9587 e 0,9580 para o coeficiente de determinação. Considerando os critérios adotados, o modelo Gompertz, seguidopor Logístico e Von Bertalanffy, apresentaram o melhor ajuste para descrever o crescimento dos machos da raça Ile de France.

The objective of this study was to evaluate the nonlinear models that best describe the growth curve of ram lambs Ile de France created in intensive system in the state of Paraná. Therefore, there were weighed fortnightly during the period from February 2013 to June 2013, from birth to slaughter (120 days) of 31 Ile de France ram lambs. Growth curves were obtained by nonlinear models Brody, Von Bertalanffy, Gompertz and Logistic in which parameters were considered maturation rate (K), asymptotic weight (A), age of the animal (t) is given by integration determining the proportion of growth after birth (B) and the proportion of asymptotic value at which the inflection point occurs curve (m) in accordance with the adopted model. The parameters were estimated by Marquardt applied to the NLIN procedure of SAS statistical program and the criteria used to verify the accuracy of the fit of the curves were the mean square of the coefficient of determination. The Brody, Von Bertalanffy, Gompertz and Logistic resulted respectively in 26.4579; 26.1668; 26.136; 26.1582 for the mean square and 0.813; 0.958; 0.958; 0.958 for the coefficient of determination. Considering the criteria assumed the Gompertz model, followed by Logistic and Von Bertalanffy, presented the best fit to describe the growth of Ile de France ram lambs.

Em decorrência do ciclo estacional das forrageiras, o uso de silagem na alimentação animal permite o suprimento de nutrientes durante o ano todo. No entanto, sua qualidade pode ser melhorada com a inclusão de aditivos e outros produtos. O glicerol constitui uma fonte rica em energia e apresenta alta eficiência de utilização pelos animais. Assim, neste trabalho, objetivou-se avaliar o efeito da inclusão de glicerol nas silagens de milho e de girassol sobre as características bromatológicas e fermentativas do material ensilado. Foram utilizadas duas fontes de silagem (milho e girassol) e quatro níveis de inclusão de glicerol (0, 15, 30 e 45%), com base na matéria seca. O delineamento experimental foi o inteiramente casualizado, em esquema fatorial (2x4) com cinco repetições. Determinaram-se os valores de pH e da composição bromatológica das silagens de milho e de girassol.Em ambas as silagens houve incremento nos teores de matéria seca, carboidratos não fibrosos e nutrientes digestíveis totais (NDT), somados à redução de proteína bruta, fibra em detergente neutro e fibra em detergente ácido com a inclusão de glicerol. A silagem de milho necessitou de 45% de inclusão de glicerol para alcançar o teor de NDT da silagem de girassol. A inclusão de glicerol nas silagens de milho e de girassol contribui com o aumento no valor nutritivo, compensando possíveis perdas de qualidade no processo de ensilagem.

Due to the seasonal cycle of forage, the use of silage to feed animals provides nutrients throughout the year. However, its quality can be improved with the inclusion of additives and other products. Glycerol is a rich source of energy and present a high efficiency of utilization by animals. The purpose of this work was to evaluate the effect of glycerol inclusion on the chemical and fermentation characteristics of corn and sunflower silages. Two silage sources (maize and sunflower) were used and four levels of glycerol inclusion (0, 15, 30 and 45%) based on dry matter were carried out. The experimental design was completely randomized in a 2 x 4 factorial arrangement with five replications. The pH values and chemical composition of corn and sunflower silages were determined. In both silages there was increment of dry matter, non-fiber carbohydrates and total digestible nutrients (TDN) added to a reduction of crude protein, neutral detergent fiber and acid detergent fiber due to the glycerol inclusion. The corn silage required 45% glycerol to achieve the TDN level of the sunflower silage. The glycerol addition contributed to the increase in the nutritional value, offsetting loss of quality in the ensiling process.

O objetivo deste trabalho foi determinar a estrutura populacional e os efeitos causados pela endogamia, em um rebanho fechado da raça Nelore da linhagem Lemgruber. O arquivo de pedigree avaliado incluiu registros de 39.290 animais, 17.646 machos e 21.644 fêmeas, nascidos entre 1951 e 2007. A estrutura da população foi analisada com uso dos programas Poprep e Endog, tendo-se determinado algum nível de endogamia em 61,82% dos animais. O valor do F médio foi 3,02% para toda a população e 4,89% para os animais endogâmicos; e o F máximo foi de 37,5%. O número de ancestrais que contribuiu para a população referência foi 2.380 animais, dos quais apenas sete explicam 50% da variabilidade genética da população. O número efetivo de fundadores (Nf) e o número efetivo de ancestrais (Na) nessa população foram 25 e 21, respectivamente. O incremento esperado de endogamia, causado pela contribuição desequilibrada dos fundadores, foi de 1,62%. A estrutura populacional do rebanho apresenta envelhecimento dos reprodutores, com consequente aumento no intervalo de gerações, além de um contínuo incremento de endogamia e alta percentagem de indivíduos endogâmicos, fatos que comprometem o ganho genético anual e que devem merecer maior atenção dos selecionadores.

The objective of this work was to determine the population structure and the effects caused by inbreeding in a closed herd of Nellore cattle of the Lemgruber line. The pedigree file included records of 39,290 animal, 17,646 males and 21,644 females, born between 1951 and 2007. The population structure was analysed using the software Poprep and Endog, which resulted in some level of inbreeding for 61,82% of the animals. The average F value was 3.02% for the whole population and 4.89% for the inbred animals; and F maximum value was 37.5%. The number of ancestors that contributed to the reference population was 2,380 animals, from which only seven explained 50% of the genetic variability of the population. The effective number of founders (Nf) and the effective number of ancestors (Na) in this population were, respectively, 25 and 21. The expected increase of inbreeding, caused by the unbalanced contribution of founders, was 1.62%. The herd populational structure shows the aging of the breeders, with a consequent increase of the generation´s interval, as well as a continuous increase of inbreeding and a high percentage of inbred individuals. Such facts compromise the annual genetic gain and should deserve a closer attention from breeders.