No abstract

No abstract

No abstract

No abstract

No abstract

Physicochemical characteristics and lipid profile of beef from cattle feeding on grazing and feedlot were compared. Forty beef samples were collected from each feeding system. The samples were taken from the Longissimus dorsi muscle. There were no differences between the feeding systems (P > 0.05) with regard to pH, luminosity index (L*), red (a*), yellow (b*), drip loss, and cooking yield. Regarding the nutritional content, there were significant differences in moisture and fat contents (P < 0.05), but not in protein or ash content (P > 0.05). The main fatty acids found were oleic, palmitic, and stearic. There was a higher concentration of unsaturated fatty acids, especially conjugated linoleic acid, on that beef from grazing bovines (P < 0.05). This information is useful for producers in the Northeastern region of Mexico, as it can help differentiate their product from the product of other similar ecological regions in Mexico and worldwide. Características fisicoquímicas y perfil de ácidos grasos de carne de res en el Noreste de México: sistema de pastoreo versus sistema confinado RESUMEN Las características fisicoquímicas, valor nutricional y perfil lipídico de la carne de bovino alimentados en pastoreo y estabulado en el noreste de México fueron evaluados en este estudio. Se colectaron 40 muestras de carne en cada sistema de alimentación. Las muestras fueron del músculo Longissimus dorsi tomadas entre la 12°y 13°costilla. El pH, índice de luminosidad (L*), rojo (a*) y amarillo (b*), perdida por goteo y rendimiento por cocción, no mostraron diferencias entre los sistemas de alimentación (P > 0.05). En el valor nutricional no se encontraron diferencias en el contenido de proteína ni cenizas (P > 0.05) pero si, en el contenido de humedad y grasa (P < 0.05). Los principales ácidos grasos en la carne de bovino fueron: oleico (C18:1, n-9), palmítico (C16:0) y esteárico (C18:0). Hubo una mayor concentración de ácidos grasos insaturados, en particular, ácido linoleico conjugado en la carne de bovinos en pastoreo (P < 0.05). Esta información es de utilidad para productores de la región noreste de México, ya que puede ayudar a diferenciar su producto del de otras regiones de México y del mundo.

The aim of this study was to evaluate the effect of herbage allowance (HA) and type of silage supplemented (TS) on milk yield, dry matter intake (DMI) and metabolism of dairy cows in early lactation. Thirty-six Holstein-Friesian dairy cows were allocated to four treatments derived from an arrangement of two HA (LHA = 17 or HHA = 25 kg of DM/cow/day) and two TS (grass (GS) or maize (MS)). Herbage allowance had no effect on DMI or milk yield. Rumen pH and NH3 -N concentration were not affected by HA. The efficiency of microbial protein synthesis in the rumen (microbial protein (MP)) was affected by HA with 21.5 and 23.9 g microbial nitrogen per kg ruminal digestible organic matter for LHA and HHA, respectively (P < 0.05). Supplementation with MS showed higher values of milk yield by 2.4 kg/cow/day (P < 0.001), milk protein content by 0.10 % (P < 0.023) and herbage DMI by 2.2 kg/cow/day, and showed lower values for milk urea compared to GS (P < 0.001). The former results suggest that TS had a greater effect on milk yield, total feed intake and energy intake than increase in herbage allowance; however, increase in HA had greater effects on MP than TS.

Introduction: The cow-calf system consists of the production of calves, which will then be fattened for meat production. The state of Tabasco a high percentage of farmers are engaged in this activity, however, most of the technology transfers are focused on the dual purpose system, which has not allowed to make significant improvements in the productive variables of the cow-calf system. The objective of this study was to characterize the cow-calf system and identify the factors that affect the production of calf in the State of Tabasco.                     Method: Therefore, 342 farmers were interviewed through a structured survey to get information about the farmer date, social characteristics, infrastructure, herd structures, management practices and productive. To identify the types of farmers, a cluster analysis was performed by the Ward method and Euclidean square distance, and to identify the variables that explain the production of calves, a linear regression analysis.Results: The cluster analysis identified three types of farmers (small, medium, and large). 63.40% of the farmers were classified as small (<of 14 cows in production), 29.0% as medium (between 15 and 34 cows in production) and 7.60% as large producers (between 35 and 80 cows in production). In the three types of farmers the number of cows in production, index of adoption of technology and quantity of concentrated feed explain the production of calf.Discussion or Conclusion: The characterization of the cow-calf system of tropical regions is important because more than half of the livestock in these regions use this system of production. In addition, knowing the factors that determine the production of calf can help generate strategies for the support of this type of farmers and improve the productive variables of the system.