Age at first calving and productive performance of primiparous Holsteins

This study investigated the age at first calving in Holstein heifers and its impact on various production parameters. A sample of 737 Holstein heifers born between 2015 and 2018 and finishing their first lactations between 2018 and 2020 was included. Cluster analysis revealed three groups based on age at first calving: high precocity, medium precocity and low precocity. Medium-precocity group exhibited the highest 305-day milk yield and peak milk production. Additionally, the same group demonstrated superior mean production per lactation, 305-day milk protein content, and 305-day milk yield. The lowest somatic cell count was found in the low-precocity group. In conclusion, medium-precocity cows showed better results such as higher 305-day milk yield and peak milk production.

Characterization of dystocia in a herd of Holstein dairy cows in Brazil

Abstract The objective of this study was to characterize calvings with low and high difficulty based on the productive and reproductive performance of dairy cows. Calvings were grouped in no calving assistance, calving with low assistance, and calving with high assistance. The original data set comprised 1,902 calving records obtained from a large dairy farm in Southeast Brazil. Factor analysis was applied using the SAS® Studio 3.8 statistical program through the factor procedure, considering the Multivariate Analysis category. Milk fat (0.92–0.79) and total solids (0.91–0.80) were strongly correlated with Factor 1. Calving interval (0.87– 0.68) and the number of AI (artificial inseminations) per conception (0.87–0.71) showed high correlations with Factor 2. Milk yield (0.84–0.76) and accumulated milk yield (0.84–0.77) were strongly correlated with Factor 3. Based on the results, we conclude that the three calving scenarios were characterized by well-defined and independent factors. Cows which required a high assistance at calving showed a lower variance explained by the model for milk fat and total solids contents, calving interval, and the number of AIs per conception.

Caracterização da distocia em um rebanho de vacas da raça Holandesa no Brasil

Resumo O objetivo deste estudo foi caracterizar os partos com leve ou severa dificuldade e diferenciá-los com base no desempenho produtivo e reprodutivo de vacas leiteiras. Os partos foram agrupados em partos sem assistência, partos com baixa assistência e partos com elevada assistência. O banco de dados original continha 1902 registro de partos que foram obtidos de uma grande fazenda comercial localizada no Sudeste do Brasil. A análise fatorial foi aplicada através do programa estatístico SAS® Studio 3.8 por meio de procedimento fatorial, considerando a categoria de análise multivariada. Os teores de gordura do leite (0,92– 0,79) e de sólidos totais (0,91–0,80) foram altamente correlacionados com o fator 1. Intervalo entre partos (0,87–0,68) e número de IA (inseminações artificiais) por concepção (0,87–0,71) apresentaram alta correlação com o fator 2. Produção de leite (0,84–0,76) e produção acumulada de leite (0,84–0,77) foram altamente correlacionados com o fator 3. Baseados nos resultados, é possível concluir que as três situações de parto foram caracterizadas por fatores independentes e bem definidos. Vacas que necessitaram de alta assistência ao parto apresentaram menor variância explicada pelo modelo para teores de gordura e sólidos totais do leite, intervalo entre partos e número de IA por concepção.

Biosecurity, environmental sustainability, and typological characteristics of broiler farms in Paraná State, Brazil

Brazil's relevant participation in the global broiler market implies the need to face a set of challenges related to biosecurity and environmental sustainability. In this study, we aimed to assess the level of biosecurity of broiler farms in Paraná State, Brazil, and investigate associations of biosecurity performance with sustainability practices and farm and farmer characteristics. Data from 70 broiler farms were collected through on-site interviews. The questionnaires included questions about production variables, biosecurity, sustainability practices, and sociodemographic characteristics of the farm operator. Biosecurity data were subjected to hierarchical cluster analysis, revealing two groups, one comprising low biosecurity farms and the other comprising high biosecurity farms. Production and sustainability data were subjected to factor analysis. Three factors were identified: Farmer knowledge and training, Mandatory environmental sustainability practices, and Non-mandatory environmental sustainability practices. Although the analyzed farms were similar in terms of production variables and operated under the same laws and contractual terms, they differed significantly in biosecurity level. These findings suggest that other factors besides production characteristics and the institutional environment may influence biosecurity, such as the importance attributed by farmers to biosecurity measures. Typological analysis revealed that high biosecurity farms had greater compliance with both mandatory and non-mandatory environmental sustainability requirements. It was also found that operators of high biosecurity farms had a higher education level than those who operated low biosecurity farms.

Environmental compliance and the level of competitiveness of tilapia producers installed in hydroelectric power plants

Aquaculture is one of the fastest-growing food sectors in Brazil. Cage fish farming has been widely practiced in the country, mainly in hydroelectric reservoirs. However, different regulatory, technical, and economic challenges may need to be overcome before the sector can achieve increased national and international competitiveness. This study aimed to analyze and compare the competitiveness of tilapia cage farms located on different sides of the Canoas I hydroelectric reservoir, which forms the border between the states of São Paulo and Paraná, Brazil. Structured questionnaires were administered to all fish farmers in the reservoir. Questions about seven competitiveness indicators were rated on a 5-point Likert scale. The results revealed that the major barriers to competitiveness are the institutional environment and environmental sustainability. Paraná has an active environmental inspection service, but São Paulo does not. As a result, tilapia fish farmers in Paraná gave more importance to environmental compliance than those located in São Paulo.

Short communication: Socio-psychological factors influencing dairy farmers' intention to adopt high-grain feeding in Brazil

This study aimed to apply the theory of planned behavior to determine the effects of attitude, perceived behavioral control, and subjective norms on the intention of dairy farmers toward high-grain feeding. Quantitative data were collected through interviews with 150 dairy farmers in Paraná, Brazil. Partial least squares structural equation modeling was used to analyze the data. We observed that farmers with a positive perception of grain feeding (attitude) and a positive perception of their ability to increase the use of grains (perceived behavioral control) had higher intention to increase grain feeding. Social pressure (subjective norm) had no effect on the intention to grain feed. These results can contribute to the development of public strategies and policies that encourage the use of high-grain diets in dairy farms.