ABSTRACT.- Understanding herbivore interaction with forage resources is crucial for effective grazing management. This study investigates the impact of sward management strategies on the foraging behavior of sheep under continuous stocking. Italian ryegrass pastures were maintained at an average sward height of 15 cm, which has been reported to be optimal for animal performance. The objective was to assess whether sheep modify their grazing behavior in response to different interventions to maintain the target sward height.

ABSTRACT.- Toxoplasmosis, caused by the obligate intracellular parasite Toxoplasma gondii, is one of the most prevalent zoonotic parasitic infections worldwide. When acquired during pregnancy, T. gondii can be transmitted to the fetus, with clinical outcomes influenced by gestational age at time of infection and the parasite's genotype. Prenatal screening enables the detection of maternal seroconversion and offers a critical window for intervention. In Uruguay, despite mandatory serological screening during pregnancy, national data on T.

ABSTRACT.- Background: Differential treatment of daughters of the same sire within a herd is modelled as the herd-sire effect. Recent changes in management practices may have led to the extensive use of certain bulls in a limited number of herds. In that case, although the effect can be well accounted for in genetic evaluation models, some approximation methods for reliabilities do not consider it correctly, leading to an overestimation of some sires' approximated reliabilities.

ABSTRACT.- Background: Ixodes fuscipes is a tick species found in the Southern Cone of America and the only member of the Ixodes ricinus complex present in Uruguay. Members of this complex are particularly recognized as vectors of diseases affecting human health, such as babesiosis, caused by parasites of the genus Babesia (Apicomplexa: Piroplasmida). However, even though potential hosts of I. fuscipes in Uruguay (rodents, birds, and artiodactyls) are known carriers of Babesia species, the potential role of I. fuscipes as a vector of piroplasmids has not been studied.

ABSTRACT.- Introduction: Varroa destructor stands as the primary global pest of honey bees, inflicting direct harm on bees while also acting as a vector for a multitude of viruses. Integrated pest management is widely recognized as the optimal strategy for minimizing acaricide application. Designed bottom boards that can limit the growth of the mite population by removing them from the hive and preventing their return and reinfestation of the colony show promising potential.

ABSTRACT.- Group A rotavirus (RVA) infections are a leading cause of neonatal diarrhoea in foals. Neonatal mice could serve as a useful tool to study the pathogenesis of equine RVA (ERVA) as well as a preclinical model for assessment of vaccine efficacy. This study aimed to comparatively evaluate the clinical, virological and pathological features of ERVA G3P[12] and G14P[12] infection in neonatal mice and compare them with porcine OSU G5P[7] and bovine UK G6P[5] RVA reference strains.

ABSTRACT.- Bromus auleticus is a perennial grass native to the campos of South America, valued for its persistence, productivity and forage quality. Conservation and breeding efforts are constrained by limited knowledge of its reproductive aspects. Although allogamy and genetic incompatibility have been reported, these traits have not been sufficiently corroborated across multiple populations. This work aimed to determine the reproductive system of B.

ABSTRACT.- This study evaluates the potential of hard hexaploid wheat (Triticum aestivum L.) lines, developed through marker-assisted selection (MAS), as an alternative to durum wheat for pasta production. Using hard hexaploid lines (SD lines) with targeted traits, such as increased gluten strength, protein content, and yellow coloration, the objective was to assess their performance relative to traditional durum wheat.

ABSTRACT.- Herbicide resistance in Conyza bonariensis (hairy fleabane) poses a significant challenge to agricultural systems worldwide. The genetic variability and prolific seed production of this species contribute significantly to its adaptative potential and fast spread in the agricultural fields. This study aimed to investigate the mechanisms underlying multiple herbicide resistance to glyphosate and ALS inhibitors in C. bonariensis biotypes from southern Brazil. Resistance factors exceeded 100 times for chlorimuron-ethyl and 49 times for glyphosate.

ABSTRACT.- Changes in light conditions may affect invasiveness as they can constrain different stages of plant development during the invasion process. This is particularly true in grazed grasslands, as livestock selectively removes above-ground biomass, promoting light heterogeneity. We assessed how light intensity and quality affect the germination and growth of Eragrostis plana, one of the most invasive alien grasses of the Río de la Plata grasslands (southern Brazil, Uruguay, and eastern Argentina).