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Efeito da variação na composição do micélio sobre a predição de desempenho predita pelo nasem 2021 em bovinos leiteiros

2026-08-13T16:44:19Z

Title: Efeito da variação na composição do micélio sobre a predição de desempenho predita pelo nasem 2021 em bovinos leiteiros Abstract: The use of the co-product mycelium in the diet of dairy cows is still limited due to the scarcity of consistent information on its chemical composition, as well as these factors can affect the prediction of performance of dairy cattle using nutritional models, such as NASEM (2021). In this sense, the objective was to evaluate the effect of the variation in the chemical composition of the mycelium on milk production estimated by the NASEM model (2021). The mycelium samples were collected in six different loads at the Dairy Cattle Sector (SEBOL) of the Glória Experimental Farm and the analyzes were carried out at the Bromatoloa and Animal Nutrition Laboratory (LABAN). In each load, ten subsamples were collected to form a composite sample, divided into three replications. The contents of dry matter (DM), mineral matter (MM), crude protein (CP), ether extract (EE); neutral detergent insoluble fiber (NDF) and acid detergent insoluble fiber (FDA). The milk production prediction model used was NASEM (Dairy 8, 2021). Three scenarios of mycelium use in confinement systems were used, with different levels of milk production (PL). Scenario 1 (PL 25 L and 11% mycelium inclusion); Scenario 2 (PL 25 L and 25% mycelium inclusion) and scenario 3 (PL 40 L and 7% mycelium inclusion). For data analysis, descriptive statistical tools were used, such as measures of central tendency (mean), dispersion (minimum and maximum values) and the coefficient of variation (CV). There was a high VC in the levels of PB, MM, EE, NDF, CNF among the loads and a low VC for DM. In addition, it was found that the highest level of mycelium inclusion (25%DM) caused a higher VC in the LP predicted by the metabolizable protein. It is concluded that mycelium has the potential to compose the diet of dairy cows, being a viable and interesting alternative to reduce feed costs. However, its use should be preceded by periodic bromatological analyses and careful formulation in the diets, since the variability of its nutritional composition can compromise the predictions of productive performance when used at higher levels of inclusion (25%) in dairy cows producing 25 liters. On the other hand, diets with lower levels of mycelium inclusion (11%) showed little variation in milk yield estimates based on both metabolizable protein and net energy, indicating greater nutritional stability and lower sensitivity to fluctuations in the chemical composition of the ingredient.

Características estruturais do capim-cayana diferido com duas alturas iniciais

2026-08-13T16:11:11Z

Title: Características estruturais do capim-cayana diferido com duas alturas iniciais Abstract: The seasonality of forage production is a challenge to obtaining pasture production during the dry season capable of meeting the requirements of animals raised on pastures. One way to overcome this problem is by using pasture management tools, such as deferment. This can be done with pastures of different initial heights, which impacts the forage mass produced and the structure of the deferred pasture. Therefore, the objective of this study was to compare the effect of two initial heights (37 and 46 cm) on the structure of hybrid Brachiaria (syn. Urochloa) cv. Cayana under a 94-day deferment period (from 19/03/2025 to 21/06/2025). The experiment was conducted in Uberlândia (MG), in two paddocks of 2800 m² each. The deferred pasture with the lower initial height (37 cm) showed lower growth (14 cm/period), a higher percentage of vegetative tillers (96%), and a lower percentage of reproductive tillers (4%), but with a lower forage mass (10,127 kg/ha of DM) compared to the deferred pasture with the higher initial height (21 cm/period; 74%; 26% and 11,482 kg/ha of DM, respectively). The lower deferred pasture showed a higher percentage of live leaves (21%) and a lower percentage of live stems (19%) than the higher deferred pasture (15% and 28%, respectively). Thus, reducing the initial pasture height for deferment was efficient in improving the pasture structure, while increasing the initial height provided a greater forage mass at the end of the deferment period.

Influência do tempo gestacional de matrizes suínas sobre o tamanho e peso dos leitões ao nascimento.

2026-08-12T06:27:08Z

Title: Influência do tempo gestacional de matrizes suínas sobre o tamanho e peso dos leitões ao nascimento. Abstract: Modern pig farming constantly seeks to optimize its productive and reproductive indexes, especially regarding reproductive efficiency and piglet viability at birth. Among the factors that influence the reproductive performance of sows, gestation length stands out for its impact on birth weight, stillbirth rate and the occurrence of mummified piglets. This study evaluated the relationship between gestation length and the reproductive performance of sows, focusing on piglet birth weight, farrowing duration and the number of stillborn and mummified piglets. The study was carried out at a Piglet Production Unit located in Monte Alegre de Minas, Minas Gerais, Brazil, involving 74 HS (Hiper Sadia) sows. A total of 74 farrowings occurring in March 2025 were analyzed. Females were monitored exclusively at the time of farrowing, with data obtained from the farm’s computerized system (S2) and by direct collection during farrowings. The experimental design was completely randomized. Data were assessed for normality and homogeneity of variance; analysis of variance (ANOVA) followed by Tukey’s test (P < 0.05) was applied to parametric variables, and the Wilcoxon test to non-parametric variables. Correlations were calculated using Pearson’s or Spearman’s coefficients according to data distribution, using the RStudio software (R Core Team, 2023). A total of 1,041 piglets were born, of which 930 were liveborn, 77 stillborn and 34 mummified. Sows with gestation length ≤115 days had a higher total number of piglets (15.53 ± 4.02) but lower mean birth weight (1.40 ± 0.26 kg), whereas sows with gestation length >115 days had fewer piglets (13.27 ± 4.60) but higher mean birth weight (1.56 ± 0.34 kg) (P < 0.05). The number of liveborn piglets was negatively correlated with mean birth weight (r = –0.60; P < 0.05), indicating that larger litters tend to produce lighter piglets. It is concluded that gestation length directly influences piglet birth weight and viability and should be considered in sow reproductive management. These findings provide support for adopting management and selection strategies that balance prolificacy and birth weight, contributing to higher productivity and profitability of the system.

Análise comparativa sobre diversidade genômica e determinantes de patogenicidade de Mycoplasma hyopneumoniae

2026-08-12T06:28:44Z

Title: Análise comparativa sobre diversidade genômica e determinantes de patogenicidade de Mycoplasma hyopneumoniae