The objective of this study was to describe barn management practices and to evaluating cow locomotion, hygiene and hock lesion prevalence of dairy cows housed in Compost Barns (CB) located in the subtropical region of Brazil. The CB has demonstrated satisfactory results in relation to animal comfort and productivity. However, modifications to the initial American recommendations are being made by producers in order to adapt it to different conditions. Thirty dairy farms were analyzed regarding structural measurements and layout, management practices, bedded pack and herd characteristics. The main results highlighted were the resting space of 14.6 m2 cow-1, most of the farms (87%) had newly built facilities and only 43.3% were built in E-W direction. Most farms did not have ridge opening and 60 % had fans in the bedded pack area, which is mostly stirred twice a day. About a third of the farms used CB only during the hottest hours of the day or rainy periods, with pasture access the remainder of the time. The bedded pack material averaged 48.4% DM, pH of 8.68, C:N of 5.90 and deep bedding temperature of 42.52 ⁰C. Locomotion scoring showed majority of the cows with a normal gait (95.5% of cows scoring 1 or 2 for locomotion). Hock lesions were observed in 15.5% of the animals and 84.0% of the cows were clean or only slightly dirty. This study indicates characteristics or issues to start an improvement process on CB usage in Brazilian subtropical region. The cow comfort was considered adequate, based on results of cow locomotion, lesions and hygiene scoring.

O uso de aditivos na alimentação de ruminantes ainda é um dilema. Diante do avanço das pesquisas voltadas à nutrição de precisão, foram descobertos uma gama de substâncias. Estes produtos atuam positivamente sobre as características do alimento ou diretamente no desempenho animal e seu uso é permitido desde que não prejudiquem o valor nutritivo da ração. Aproximadamente quatro fatores devem ser considerados ao determinar se um aditivo alimentar deve ser usado: resposta esperada, retorno econômico, pesquisa disponível e respostas de campo. No entanto, a permissão do uso no Brasil é regulamentada pela IN 44/ 2015, e vai muito além destes fatores. Atualmente os aditivos agrupados em quatro categorias (tecnológico, zootécnico, sensorial ou nutricional) e inúmeros grupos funcionais. Nos últimos anos os nutricionistas têm afirmado que a maioria de seus clientes usam algum tipo de aditivo na ração, por este motivo há necessidade de se conhecer as alternativas, bem como as características do regulamento que administra o uso das substâncias.

This study aimed to examine the relationship between a high somatic cell count (SCC) in cows and milk quality during the hot season in different breeds. Milk samples from 500 cows in the hot season and 431 in the cold season of 2022 were collected across 39 farms in Santa Catarina, Brazil. The samples were analyzed for SCC, milk composition, and physical attributes. Cows were also evaluated for udder depth, udder clearance, teat-end condition, and leg and udder cleanliness. Based on the SCC levels, cows were categorized as low (≤200,000 cells/mL), medium (>200,000 and ≤615,000), or high (>615,000). Data were analyzed by ANOVA with a statistical model that included the effects of the SCC class, season, days in milk, parity, genetic group, and the interaction of the SCC level and season. The results showed that cows with a high SCC produced less milk with lower component levels but higher chloride content. Milk from the hot season had lower acidity and reduced component levels. The impact of SCC on the physical traits of milk did not vary with season. Furthermore, cows with deeper udders and lower udder clearance were more likely to have a high SCC, regardless of genetics. Both a high SCC and hot temperatures independently compromised milk yield and quality, thereby increasing the risk of culling. Therefore, improving udder conformation and avoiding cows with deep udders may help to reduce SCC levels.

The objective was to classify the dairy farms that use Compost bedded pack barn (CB) in the Brazilian subtropical region, in terms of farm structure, building aspects, environmental and compost bedded pack characteristics, and reports the variability among them. Additionally, this research identifies structural and management factors that interfere in the compost bedded pack quality. Farms (n = 30) were visited (January-March 2017), located on Subtropical region of Brazil, where CB measurements, managements and herd observations were performed. The cluster analysis was performed with the kmeans methodology to define the groups, and through iterations, the optimal number of groups was determined according to the Silhouette method. Descriptive statistics were used for the different groups of farms. The clustering analysis, based on 12 variables, resulted in the formation of three groups: “Conventional and adapted CB” (n=18, with new and adapted barns, of different sizes, full time using, with adequate pack characteristics or not), “Large conventional CB” (n = 6, larger barns, more similar to American models, full time using) and, “CB of partial use” (n = 6, used in hottest hours of the day or rainy season, with better pack characteristics among groups, although do not have fans ventilation and the bedded pack is stirring only once a day). The CB systems are heterogeneous, and the barns are characterized by their distinct sizes or period of utilization. The group “CB of partial use” presented better bedded pack characteristics even with less intensive bedding management, and without fan ventilation in the barns.

There is currently no established information for assessing the general welfare conditions and behavior of dairy cows housed in compost-bedded pack barns (CBPs) that allow access to pasture. Therefore, the objective of this study was to evaluate and classify the welfare and behavior of dairy cows in three different housing conditions within CBPs in southern Brazil. During both the cold and hot seasons, nine farms were divided into three groups: CONV (conventional, large, full-time barns), ADAP (conventionally adapted, full-time barns), and PART (part-time barns). The European Welfare Quality^® (WQ^®) protocol takes into account the characteristics of the animals, animal housing, and farm management to set an overall score to assess animal welfare, which is why WQ^® was used in this study. Daytime behavior was monitored over a period of four consecutive hours on two days. The 29 WQ^® measures were grouped into 11 criteria, then into four principles, and finally into the general welfare category. The experimental design employed was a randomized block design in a 2 × 3 factorial scheme (two climatic seasons and three groups), with the means of the measures, principles, and criteria for each group, season, and interaction (group × season) compared using the Tukey test. The diurnal behavior of the cows was described by the average absolute frequency of each observed behavioral measure. There were no differences among the groups in any of the measures assessed by the WQ^® protocol. However, there was a significant increase in both the incidence of diarrhea and the duration of lying down during the cold season. Only the principle of appropriate behavior varied among the groups, with the PART group demonstrating superior scores. Regardless of the season, the welfare of dairy cows maintained in CBPs was classified as “improved”. No abnormalities in behavior were observed among cows housed in the different groups or seasons. Cows in the PART group laid down less frequently during the hot season. Overall, the CBP system provided favorable welfare and behavioral conditions for cows in Brazil, and access to grazing further enhanced the welfare of animals housed in the PART group.

Objetivo. Los objetivos de este estudio fueron evaluar si la calidad del calostro se modifica por las características genéticas, fisiológicas y de manejo en el período pre-parto, así como evaluar si la calidad y composición del calostro se altera en el proceso de congelación. Material y métodos. En el experimento I, se recogieron muestras de calostro y sangre de 35 vacas (18 Holstein y 17 Jerseys). En el experimento II, se recolectaron seis muestras de calostro de vacas Holstein y se congelaron durante 60 días. Resultados. La concentración media de inmunoglobulina G (IgG) fue de 77.65 mg/ml en Jersey y de 82.77 mg/ml en Holstein. La genética, el orden de parto y la interacción entre estos factores no fueron significativos en la concentración de IgG en el calostro. Además, se observó un efecto genético de la vaca en el peso en la cría al nacer y en los tres días de edad (p<0.0001). Las razas de becerros Holstein (83%) y Jersey (82%) mostraron niveles de proteína sérica total por encima de 5.5 g/dL. Las vacas Holstein alojadas en potreros individuales con suplementos dietéticos, proporcionaron una mejor calidad de calostro (93.57 mg IgG/mL). Con el tiempo, el porcentaje de grasa cambió al congelarse, que se redujo con el tiempo (p<0.05) en el Experimento II. Conclusiones. El manejo previo al parto influye en la calidad del calostro, y la congelación no interfiere en la calidad centesimal e inmunológica del calostro, con excepción de la grasa, que disminuye a lo largo del tiempo.