Since 2010, South America has been experiencing a prolonged megadrought, with a 40% reduction in annual rainfall, further intensified by climate change. This situation has led to a severe decline in water reserves, impacting agriculture and food security. To mitigate these effects, the adoption of sustainable agricultural practices, such as the use of sheep wool as an organic fertilizer, has been explored. This study evaluated the impact of wool pellets on lettuce growth and soil properties across different substrates. Lettuce seedlings were cultivated in 1 L pots with various soil types (sand, clay, and peat) and different wool pellet doses: a control group (C), a group with 5 g/L (W5), and one with 10 g/L (W10). Plant growth parameters and soil properties were monitored over a period of 120 days. The addition of wool pellets improved soil moisture retention and chemical properties, with moisture levels increasing by 3% to 25% compared to the control, particularly during dry periods. An increase in nitrate (41-54%) and potassium (10-53%) concentrations was observed in both soil and lettuce leaves (1.4 times) compared to the control, particularly in sandy and clay soils. Lettuce growth was significantly enhanced under the W10 treatment, which showed the highest increases in plant weight (2.5 times), leaf number (1.4 times), and height (1.4 times) compared to the control. Wool pellets may thus serve as an effective tool for optimizing soil management in low-fertility environments, promoting more sustained and resilient plant growth under variable water availability.

El estudio evaluó la repetibilidad de la respuesta superovulatoria en 12 ovejas Merino Australiano durante la estación reproductiva en uno (G1), tres (G2) y cuatro (G3) años consecutivos. Se utilizó un protocolo modificado basado en 200 mg de pFSH en ocho dosis decrecientes (intervalos de 12 h) y estrategias de apoyo tales como el cambio del CIDR al día 7, el rociado de los cuernos durante el procedimiento con solución salina con heparina y el uso de Flunixin Meglumine. No se encontraron diferencias significativas en el número total de estructuras recuperadas durante los años de aplicación del protocolo de superovulación (G1=8±2, G2=18±3, G3=19±4; p>0.05). Se observó una alta repetibilidad, tanto para el número total de embriones como para el número de embriones transferibles en G2 y G3. El tratamiento superovulatorio durante 3 y 4 años sucesivos no afectó la eficacia de la recuperación de embriones.

This study evaluated the effect of short-term prepartum supplementation of ewes with two gluconeogenic precursors propylene glycol (PG) and calcium propionate (CP) in the Chilean drylands with a Mediterranean climate. We started with 22 adult Romanov ewes with a low body condition score and synchronized in estrus. After pregnancy diagnosis, we selected 18 ewes with two or three gestations and randomly assigned them to three groups: the control group (CG; n = 6), the PG group (n = 6), and the CP group (n = 6). We supplemented the PG and CP groups for 10 days before the estimated lambing date. We measured the β-hydroxybutyrate (BHB), non-esterified fatty acids (NEFA), and glucose plasma levels as well as the body condition score (BCS) at 3 timepoints: 10 days before lambing, right after lambing, and day 10 postpartum. In addition, we weighed the lambs at birth and on day 10 postpartum. The BHB level right after lambing decreased in the PG and CP groups compared with the CG (P < 0.05). The NEFA level did not vary between the groups at the different timepoints. The glucose level increased approximately 2–3-fold (P < 0.05) in all ewes after lambing and decreased on day 10 postpartum, but there were no significant differences between the PG and CP groups (p > 0.05). In addition, the BCS did not differ between the groups at any time point (P > 0.05). The weight of the lambs on day 10 postpartum increased significantly (P < 0.05) in the PG and CP groups compared with the CG. In addition, the mean daily weight gain was approximately 50% higher in the PG and CP groups compared with the CG (P < 0.05). Based on these findings, short-term prepartum supplementation with PG or CP reduced the BHB level in ewes with a low BCS and multifetal gestations during lambing and improved the lamb weight on day 10 postpartum. Therefore, the administration of these additives could be a useful strategy in sheep under feed restrictions in the Chilean drylands with a Mediterranean climate at times of high nutritional requirements.