The objective of the research was to evaluate three synchronization protocols for fixed‐time artificial insemination (FTAI) inBos indicuswithBos tauruscrossbred cows. Forty‐five cows of 5 ± 1.6 years were selected. The Jsynch treatment consisted of the application of an intravaginal device plus benzoate; on day 8, the device was removed and PGF2α, estradiol cypionate plus eCG was applied, and the FTAI was performed at 48–52 hours after. Conventional treatment consisted of the application of an intravaginal device plus benzoate; on day 8, the device was removed and PGF2αplus eCG was injected, and on day 9, estradiol benzoate was administered, and FTAI was performed at 30 hours. The Ovsynch treatment consisted of the application of GnRH, and on day 8, PGF2αwas applied, on day 9, GnRH was applied again, and on day 10, FTAI plus GnRH was applied. The diagnosis of pregnancy was determined by transrectal ultrasound 45 days after the FTAI. The Jsynch (39.1%) and conventional (39.1%) treatment showed higher pregnancy compared to the Ovsynch treatment (21.7%) of pregnancy. The presence of crystalline mucus at the time of the FTAI was significantly associated with pregnancy. The results of this investigation indicate that it is possible to obtain acceptable pregnancy rates with the FTAI inB. indicuswithB. tauruscrossbred milk‐producing cows, and treatments with progesterone‐releasing devices plus eCG can improve the reproductive performance of cows.

Urochloa brizantha (Brizantha) is cultivated under varying altitudinal and management conditions. Twelve full-sun (monoculture) plots and twelve shaded (silvopastoral) plots were established, proportionally distributed at 170, 503, 661, and 1110 masl. Evaluations were conducted 15, 30, 45, 60, and 75 days after establishment. The conservation and integration of trees in silvopastoral systems reflected a clear anthropogenic influence, evidenced by the preference for species of the Fabaceae family, likely due to their multipurpose nature. Although the altitudinal gradient did not show direct effects on soil properties, intermediate altitudes revealed a significant role of CaCO₃ in enhancing soil fertility. These edaphic conditions at mid-altitudes favored the leaf area development of Brizantha, particularly during the early growth stages, as indicated by significantly larger values (p < 0.05). However, at the harvest stage, no significant differences were observed in physiological or productive traits, nor in foliar chemical components, underscoring the species’ high hardiness and broad adaptation to both soil and altitude conditions. In Brizantha, a significant reduction (p < 0.05) in stomatal size and density was observed under shade in silvopastoral areas, where solar radiation and air temperature decreased, while relative humidity increased. Nonetheless, these microclimatic variations did not lead to significant changes in foliar chemistry, growth variables, or biomass production, suggesting a high degree of adaptive plasticity to microclimatic fluctuations. Foliar ash content exhibited an increasing trend with altitude, indicating greater efficiency of Brizantha in absorbing calcium, phosphorus, and potassium at higher altitudes, possibly linked to more favorable edaphoclimatic conditions for nutrient uptake. Finally, forage quality declined with plant age, as evidenced by reductions in protein, ash, and In Vitro Dry Matter Digestibility (IVDMD), alongside increases in fiber, Neutral Detergent Fiber (NDF), and Acid Detergent Fiber (ADF). These findings support the recommendation of cutting intervals between 30 and 45 days, during which Brizantha displays a more favorable nutritional profile, higher digestibility, and consequently, greater value for animal feeding.

La producción pecuaria pretende lograr mayor productividad, utilizando insumos en la alimentación de especies que sean cultivadas con el menor impacto para el medio ambiente. Determinamos la mejor respuesta productiva e integridad intestinal de cuyes alimentados con forraje de maíz inoculado con microorganismos eficientes. Empleamos 48 cuyes (24 machos y 24 hembras), de 50 días de edad, de la raza Perú con peso vivo promedio de 450 – 550g. Evaluamos el consumo de ración (g), incremento de peso (g), conversión alimenticia, longitud de vellosidad intestinal (µm) y profundidad de la cripta (µm). Los cuyes machos obtuvieron el mayor consumo ración (449 g), el mayor (P<0,05) incremento de peso (746,3 g) y la mejor conversión alimenticia (0,6). Además, registraron la mayor longitud de vellosidad intestinal (0,507µm) y profundidad de la cripta (0,141µm). El tratamiento con forraje de maíz inoculado con bacterias rizosféricas B5 y SMN3 obtuvo el mayor incremento de peso (736 g). La conversión alimenticia más eficiente la evidenció el forraje de maíz sin inoculación de bacterias benéficas (0,57). Además, este forraje registró una mayor profundidad de la cripta.

This study evaluated the effects of stingless bee (Melipona) pollen supplementation on productive performance, carcass traits, hematological parameters, lymphoid organs, and bone histomorphometry in slow-growing chickens. A total of 200 one-day-old mixed-sex chickens were distributed in a completely randomized design with four dietary treatments: a control diet and diets supplemented with 4, 8, and 12 g of bee pollen per kg of feed, with five replicates of ten birds each, from 1 to 30 days of age. Productive performance was assessed, and carcass yield, edible viscera, lymphoid organs, blood parameters, and tibia morphometry were evaluated at 30 days. Data were analyzed using ANOVA followed by Tukey’s test (p < 0.05). Feed intake, carcass yield, noble cuts, and edible organs were not affected by pollen inclusion. However, weight gain and feed conversion ratio were negatively affected at inclusion levels above 4 g/kg. Hematological analysis revealed significant changes in total leukocytes, lymphocytes, eosinophils, and monocytes, suggesting immunomodulatory effects of pollen supplementation. No significant differences were observed in bone histomorphometric traits. In conclusion, dietary inclusion of 4 g/kg of Melipona pollen can be used as a functional feed additive in slow-growing chickens, providing immunological modulation without impairing productive performance or bone integrity.