ABSTRACT.- Feed efficiency significantly impacts the economics of beef production and is influenced by biological and environmental factors. The rumen microbiota plays a crucial role in efficiency, with studies increasingly focused on its relationship with different rearing systems. This study analyzed 324 rumen samples from bulls and steers categorized as high and low efficiency based on residual feed intake. The animals were fed two diets (postweaning and finishing) and rumen samples were sequenced using a reduced representation sequencing (RRS) based approach.

ABSTRACT.- Our objective was to compare performance and carcass characteristics of backgrounding steers grazing poor quality pasture, receiving energy or protein supplements during summer, and on subsequent finishing period. Sixty Hereford steers (14 months; 348+-3 kg body weight [BW]) were blocked by BW and randomly assigned to one of three treatments (n = 20 per treatment): control (non-supplemented) and supplemented at 0.8% BW with whole grain of corn (CS) or lupin bean (LS) (phase I; 77 days). Over the following 84 days, none of the steers had access to supplement (phase II).

ABSTRACT.- Underutilized sheep and goat breeds can adapt to challenging environments due to their genetics. Integrating publicly available genomic datasets with new data will facilitate genetic diversity analyses; however, this process is complicated by data discrepancies, such as outdated assembly versions or different data formats. Here, we present the SMARTER-database, a collection of tools and scripts to standardize genomic data and metadata, mainly from SNP chip arrays on global small ruminant populations, with a focus on reproducibility.

ABSTRACT.- Context: Implementing heterogeneous rural landscapes with high agricultural diversity and a substantial proportion of natural habitats has been proposed to ensure food production while reducing negative impacts on ecosystem services. However, evidence of an increased supply of ecosystem services (ES) in more heterogeneous landscapes remains limited, with no consensus. Objectives: To evaluate the effect of the spatial cropland system's diversity and landscape configuration on indicators of the supply of ES in agricultural landscapes of the Rio de la Plata Grasslands region.

ABSTRACT.- The leafminer Phytomyza rufipes Meigen, 1830 (Diptera, Agromyzidae) is an oligophagous pest of plants of the family Cruciferae. These include Canola, Brassica napus L. We report the record of P. rufipes in Uruguay, which is confirmed through molecular characterization using DNA barcoding. Characteristic damage symptoms and immature stages of the pest were first confirmed on a Canola crop in Flores, Uruguay. © The authors.

ABSTRACT.- Including hairy vetch (Vicia villosa Roth.) in a crop sequence before maize (Zea mays L.) can enhance the cash crop grain yield and reduce nitrogen (N) fertilizer needs, though the effects are inconsistent. This study aimed to identify the variables influencing maize grain yield response to hairy vetch as a preceding cover crop and N fertilization in maize following hairy vetch. We conducted 70 experiments evaluating four treatments resulting from the inclusion (or not) of hairy vetch previous to maize with and without subsequent N fertilization. © 2024 Elsevier B.V.

ABSTRACT.- The emergence of plant pathogens is often associated with waves of unique evolutionary and epidemiological events. Xanthomonas hortorum pv. gardneri is one of the major pathogensca using bacterial spot disease of tomatoes. After its frst report in the 1950s, there were no formal reports on this pathogen until the 1990s, despite active global research on the pathogens that cause tomato and pepper bacterial spot disease. Given the recently documented global distribution of X. hortorum pv. gardneri, our objective was to examine genomic diversification associated with its emergence.

ABSTRACT.- Diaphorina citri poses a serious threat to citrus. Here, the nymphicidal activity of mineral and soybean oils, organosilicon, and citrus-essential-oil-derived adjuvants was evaluated. Additionally, mineral and soybean oils were studied for antifeedant and repellent effects on adults. Residual effect on the parasitoid Tamarixia radiata was also assessed. Nymphicidal activity ranged between 65-83%, with Silwet enhancing mineral and soybean oil efficacy. Evaluated soybean and mineral oil exhibited comparable antifeedant and repellent effects on adults.

ABSTRACT.- Silvopastoral systems may provide important production and environmental benefits. The loss of cool-season (C3) grasses from temperate grazed native grasslands is associated with selective grazing and excessive solar radiation that limit their survival. Silvopastoral systems integrate trees with grasslands that provide shade to both cattle and herbaceous plants, potentially favoring C3 species. There is limited information about the effect of trees on the species and functional composition of native grasslands in the Campos biome in South America. The objective

ABSTRACT.- Random-regression models (RRM) are used in national genetic evaluations for longitudinal traits. The outputs of RRM are an index based on random-regression coefficients and its reliability. The reliabilities are obtained from the inverse of the coefficient matrix of mixed model equations (MME). The reliabilities must be approximated for large datasets because it is impossible to invert the MME. There is no extensive literature on methods to approximate the reliabilities of RRM when genomic information is included by single-step GBLUP.