ABSTRACT. The objective of this study was to evaluate the productivity and health of fattening lambs fed different levels of coffee pulp in their diets. Thirty-five crossbred lambs with an average weight of 21.8 kg were fed isoproteic and isoenergetic diets with different percentages of coffee pulp (T0: control; T1: 7%; T2: 14%, T3: 21% and T4: 28%), the base diet was formulated with corn, soybean meal, alfalfa stubble, molasses, urea and mineral salt. The fattening period was 98 days. Productivity was measured by weight gain, feed intake and feed conversion. At the beginning and end of the study, blood samples were taken to determine the health status using a biochemical profile and blood count. Analysis of variance was performed using the initial weight as the covariate for the productive variables and the initial values of the analytes in the blood chemistry and hematological analysis tests. The coffee pulp did not affect productivity, although the amount of neutrophils decreased (P<0.05) as the coffee pulp in the diet increased. In all treatments, urea exceeded the reference values, whereas creatinine was below the reference values. We concluded that the inclusion of up to 28% coffee pulp in the diet did not affect the productive parameters, decreases the neutrophil count without affect health status of lambs during fattening.

Creole sheep in México have undergone crossbreeding, provoking the loss of genetic variability. The objective of the present study is to determine the intra-racial genetic diversity, the genetic relationship with other genotypes, and the populational substructure of the Oaxacan Creole sheep. Twenty-nine blood samples were obtained of Creole sheep of the Oaxaca Mixteca region in México. A genetic analysis was made with 41 microsatellites recommended for studies of genetic diversity in sheep. An analysis was made of genetic diversity, populational structure, and genetic distance with 27 other sheep populations. The study found 205 alleles with a range of 2 to 9 by locus and an effective number of 3.33. The intra-racial analysis showed a moderate genetic diversity with values of expected heterozygosity of 0.686 and observed of 0.756, a mean polymorphic information content of 0.609, and a mean coefficient of consanguinity of −0.002. In interracial genetic diversity for the coefficients of consanguinity, the values were FIS = 0.0774, FIT = 0.16993, and FST = 0.10028, showing an elevated genetic distance with other creole breeds, but close to Argentine Creole, to another Creole of México and the Spanish Merino. Its genetic structure showed that it does not have any populational subdivision nor mixes with the others analyzed. It is concluded that it is a distinct and isolated population and is proposed as the creole breed “Chocholteca” for its conservation.

Objetivo: Determinar el rendimiento y las características sensoriales de quesos frescos elaborados con leche Positiva a la Prueba del Alcohol. Diseño/metodología: Se utilizó leche fresca proveniente de vacas cruzas de Brahman x Suizo Pardo Americano, las cuales se mantuvieron en pastoreo. Se seleccionaron once jueces con categoría de semientrenados. En el análisis sensorial se utilizaron las pruebas, triangular, dos de cinco, de aceptación, perfil de textura y perfil de sabor. En los perfiles de sabor y textura se utilizó una línea de 10 cm para señalar la intensidad. La prueba de aceptación se realizó a 50 consumidores sin entrenamiento. Los datos obtenidos se sometieron a un análisis de varianza, el efecto fijo y la respuesta positiva o negativa de la leche a la prueba del alcohol; la diferencia entre promedios se determinó con la prueba de Tukey (P≤ 0.05). Resultados: Se observó que el queso elaborado con leche Positiva a la Prueba del Alcohol presenta una menor aceptación (P≤0.05), mayor intensidad de dureza y porosidad y un menor sabor residual (P≤0.05). Limitaciones del estudio/implicaciones: El resultado a la prueba del alcohol es variable, por lo que es necesario hacer la prueba diariamente para separar la leche. Hallazgo/conclusión: El queso elaborado con leche positiva a la prueba del alcohol tiene menor aceptación por el consumidor debido a sus características organolépticas.

Objective: To establish milk stability using the alcohol test in cows with different feeding strategies in the tropical dairy system. Design/methodology/approach: Ten crossbred Holstein x Zebu cows whose milk frequently tested positive to the alcohol test were housed in individual yards and distributed into two groups. Experiment 1. T1: cows consumed dry Pangola grass (Digitaria eriantha); T2: cows consumed green Maralfalfa grass (Pennisetum violaceum). Forage was provided ad libitum. Experiment 2. T1 cows were supplemented with a concentrate with higher crude protein and metabolizable energy percentage than T2 cows; this percentage was gradually increased up to 4.0 kg. Milk was subjected to alcohol testing. Variance analyzes were performed under categorical data models. Results: Higher percentages of cases that tested positive for alcohol were observed in cows that consumed dry grass than in cows that consumed green grass (P<0.05). The concentrate addition to diets based on dry or green forage reduced the positive case percentage. Implications: A balanced diet improves milk stability. Findings/conclusions: The improvement in the cows’ nutritional value decreases the percentage of milk with positive results in the alcohol test.

Objetivo. Evaluar la respuesta reproductiva, estado metabólico y cambios corporales en ovejas Dorper y Katahdin suplementadas con dos niveles de energía previo al empadre. Materiales y métodos. Se utilizaron 14 hembras Katahdin y 13 Dorper distribuidas en 2 tratamientos a las cuales se les sincronizó el celo. Catorce días previo a la sincronización de estros, las ovejas se distribuyeron en 2 tratamientos de acuerdo con el nivel de energía en la dieta, T1:2.0 y T2:2.5 Mcal kg-1 de EM. La alimentación abarcó 14 días de adaptación y 14 de alimentación con dieta integral. Al inicio y al final del estudio se midió el espesor de grasa dorsal, área del ojo de la costilla, peso corporal y concentraciones de glucosa e insulina. Se midieron los principales parámetros reproductivos como respuesta a estro, porcentaje de gestación y prolificidad. Se realizaron análisis de varianza y pruebas de ji cuadrada para determinar el efecto del nivel de energía y el genotipo. Resultados. El genotipo y el nivel de energía no afectaron ninguna de las variables medidas, aunque se encontró que con ambos niveles de energía existió un incremento en las concentraciones de glucosa, así como una ganancia en peso, grasa corporal y área del ojo de la costilla. Conclusiones. Debido a que no existió diferencia en los parámetros reproductivos y cambios corporales en ovejas al alimentarlas con los dos niveles de energía, es mejor la alimentación con 2.0 Mcal kg-1 de EM, ya que reduce costos de alimentación.