Reviewing the current state of knowledge on reproductive performance and productive traits in rams has many advantages. First, the compilation of this information will serve as a literature resource for scientists conducting research around the world and will contribute to the understanding of the data collected and interpreted by researchers on the different hormonal strategies used to improve reproductive performance in rams. Second, it will allow scientists to identify current knowledge gaps and set future research priorities in ram reproduction. Rams play an important role in the global flock economy, but their reproductive analysis has been limited in the use of hormonal technologies to increase the productivity of sheep flocks. In this review, we cite the most important works on six hormones that, in one way or another, modify the hypothalamus-pituitary-gonadal axis, at different doses, in and out of the reproductive season, breeds, application methods, among other factors. The overall aim is to increase the reproductive efficiency of rams in different scenarios and, in some cases, of other species due to the lack of limited information on rams.

El objetivo del estudio fue evaluar el efecto de la alimentación húmeda de cerdos en finalización (alimento:agua, 1:1) de una dieta basada en sorgo y harina de soya (15.0% PC, 3,200 kcal EM/kg MS), sobre el comportamiento productivo, composición de la canal y calidad de la carne. Dieciséis cerdos cruzados (York-Landrace x Duroc) de 68.4±2.4 kg de peso fueron alojados individualmente, y asignados a dos tratamientos (n=8 repeticiones por tratamiento): AS, alimentación seca; AH, alimentación húmeda. Alimento fue ofrecido diariamente en dos porciones iguales (0800 y 1500 h) durante cinco semanas. Semanalmente se registraron el peso vivo (PV) y el consumo de alimento individuales, para calcular ganancia diaria de peso (GDP) y eficiencia alimenticia (EA). Se midió la composición de la canal; la calidad de la carne fue medida en muestras de Longissimus dorsi. Cerdos AH tuvieron mayor (P<0.05) PV final (108.4 vs 101.9 kg) y GDP (1.043 vs 0.990 kg/día) que los cerdos AS. Cerdos AS tuvieron menor consumo (semana 5) y EA (semana 3) que los cerdos AH (Interacción Tratamiento x Semana, P<0.05). Cerdos AH tuvieron pesos mayores de pierna, canal caliente y fría (P0.05) entre tratamientos. Valores de dureza, adhesividad, masticabilidad y resistencia fueron menores (P<0.05) en carne de cerdos AH. En conclusión, los cerdos que recibieron alimento húmedo tuvieron mejor comportamiento productivo, composición de la canal y características de la carne que cerdos que recibieron alimento seco.

Archivos Latinoamericanos de Producción Animal, es la publicación oficial de la Asociación Latinoamericana de Producción Animal Japanese quail is a species with great productive potential, requiring a diet balanced in energy and nutrient to meet the nutritional requirements. Conventional diets use mostly grains as energy sources, oilseed meals as the main source of amino acids, and limestone as source of calcium. The objective of the present study was to evaluate the nutritive value of dried citrus peel meal (HCN), and eggshell meal (HCH), to be used as unconventional sources of energy and calcium for balanced diets for laying quails. Combined Inclusion of 0, 5 and 10% dried citrus pulp and 0, 1, and 2 % of eggshell meal did not affect daily intake nor feed conversion rate of laying quails, though it has positive effects on pigmentation of yolk. La codorniz japonesa es una especie avícola promisoria por su gran eficiencia productiva, que para la adecuada producción de huevo requiere de alimentación balanceada en nutrientes y energía para cubrir sus requerimientos. Las dietas convencionales contienen mayormente granos como fuentes de energía y harinas de semillas oleaginosas como fuentes de aminoácidos. En el presente trabajo se determinó in vivo el valor nutricional de la harina de cáscara de naranja (HCN) y la harina de cascarón de huevo (HCH), para ser utilizadas como fuentes no convencionales de energía y calcio para dietas balanceadas de codornices de postura. La inclusión combinada de 3 niveles de harina de cáscara de naranja (0, 5, y 10 %) y harina de cascarón de huevo (0, 1 y 2 %) no afectó el consumo de alimento, ni la conversión alimenticia de las aves, y tiene efectos positivos en la pigmentación de la yema del huevo. A codorna japonesa é uma espécie avícola promissora devido à sua grande eficiência produtiva, que para a produção adequada de ovos requer uma dieta balanceada em nutrientes e energia para cobrir suas necessidades. As dietas convencionais contêm principalmente grãos como fontes de energia e farinhas de oleaginosas como fontes de aminoácidos. No presente trabalho foi determinado o valor nutricional da farinha de casca de laranja (HCN) e farinha de casca de ovo (HCH) in vivo, para serem utilizadas como fontes não convencionais de energia e cálcio para dietas balanceadas de codornas poedeiras. A inclusão combinada de 3 níveis de farinha de casca de laranja (0, 5 e 10%) e farinha de casca de ovo (0, 1 e 2%) não afetou o consumo de ração ou a conversão alimentar das aves e tem efeitos positivos na pigmentação da gema de ovo.

The impact of social rank among hair rams on reproductive efficiency has been extensively studied, particularly regarding its influence on ewes and rams under various lambing scenarios, both within and outside the breeding season. However, limited information exists on the specific effects of social rank on lamb paternity. The present study aimed to evaluate the influence of social rank during a 35 d mating period on paternity outcomes and the postnatal development of lambs during the breeding season. A total of 108 adult ewes were divided into six groups, with 18 ewes per group. Each group was paired with two rams: one dominant ram (DRam) and one subordinate ram (SRam). Lamb development was monitored from birth through weaning and up to 150 d of age. Paternity was determined for 107 lambs using a panel of 116 single-nucleotide polymorphism (SNP) markers to assign sires from among the 12 rams included in the study. Social rank showed significant differences in lambing outcomes depending on the type of birth (P<0.05). DRams sired 67 % of lambs, while SRams sired 33 %. DRams exhibited a significantly higher proportion of twin births (52.9 %) compared to SRams (32.4 %; P<0.01). However, no significant differences were observed between the ram groups for other lambing types. Lambing type also significantly influenced lamb weight gain, with single-born lambs achieving greater weight gain than twins and triplets (P<0.05). Additionally, lamb sex ratios differed significantly between ram groups, with DRams producing a higher proportion of male lambs (50.7 %) compared to SRams (41.2 %; P<0.05). This study demonstrates that social rank significantly affects reproductive outcomes, including lamb paternity, lambing type, birth weight and body weight at 3 months of age. These findings highlight the importance of considering social hierarchy when managing breeding programs to optimize reproductive efficiency in hair sheep production systems.