ABSTRACT.- Determining the optimal defoliation frequency is essential to increase the productivity of pasture-based dairy systems. An experiment was carried out to study the effect of the defoliation regimen around flowering time on the evolution of chemical composition and nutritional value of orchardgrass. The experiment was conducted on a 4-year-old orchardgrass (Dactylis glomerata cv 'INIA Perseo') pasture at the experimental station "La Estanzuela" (INIA, Uruguay).

ABSTRACT.- Efficient pasture-based animal production systems require optimisation of forage production with the highest nutritive value. Increasing the defoliation regimen of pastures allows to improve the nutritive value of forage for ruminants but it can be detrimental for total biomass production. An experiment was carried out to study the effect of the defoliation regimen around flowering time on productivity, chemical composition and nutritional value of tall fescue.

ABSTRACT.- Two experiments evaluated the effect of different hormonal treatments to synchronize follicle wave emergence on follicle dynamics and pregnancies per AI (P/AI) in estradiol (E2)/progesterone (P4) timed-AI (TAI) protocols in lactating dairy cows. © 2024 Elsevier Inc.

La enfermedad llamada "achaparramiento del maíz", es causada por cuatro patógenos transmitidos por la chicharrita Dalbulus maidis. Esta plaga es la principal amenaza del cultivo en algunos países de América Latina. El control eficaz de la chicharrita del maíz depende del tamaño de la población. Es esencial llevar a cabo un monitoreo constante y aplicar medidas preventivas y culturales para disminuir las poblaciones del vector y proteger los cultivos de maíz. ---- CONTENIDO:Primera detección:¿Mi chacra está en riesgo? -- Identificación del vector.

ABSTRACT.- Microinjection of CRISPR/Cas9 requires the availability of zygotes that implies animal breeding, superovulation schemes, and embryo collection. Vitrification of zygotes may allow having ready-to-use embryos and to temporally dissociate the workload of embryo production from microinjection. In this study, fresh (F group) or vitrified (V group) zygotes were microinjected with CRISPR/Cas9 system to test the hypothesis that vitrified zygotes could be a suitable source of embryos for microinjection.

ABSTRACT.- Bovine torovirus (BToV) is an enteric pathogen that may cause diarrhea in calves and adult cattle, which could result in economic losses due to weight loss and decreased milk production. This study aimed to report the presence, the genetic characterization and the evolution of BToV in calves in Uruguay. BToV was detected in 7.9% (22/278) of fecal samples, being identified in dairy (9.2%, 22/239) but not beef (0.0%, 0/39) calves. BToV was detected in both diarrheic (14%, 6/43) and non-diarrheic (13.2%, 5/38) dairy calves.