Effects of crossbreeding on carcass and meat quality of Mexican lambs / Efeito do cruzamento sobre o rendimento de carcaça e a qualidade da carne de cordeiros mexicanos

Twenty hair (Pelibuey x Katadin x BlackBelly) and 20 wool (Rambouillet x Criollo) lambs were fattened in an intensive feeding system to reach 40kg body weight at ten months of age. The yield of lamb sides and back fat (51.9 percent, 2.5mm vs. 47.0 percent, 2.3mm) were greater in wool lambs. Meat pH was not different between phenotypes but meat temperature was higher during the first hours postmortem in wool lamb sides (27, 23, and 20, vs. 24, 20, and 17ºC). Protein content in meat from the neck (braquicephalic and esternocephalic muscles) and loin (Longissimus lumborum muscle) were higher in hair lambs (21.1 and 20.4 vs. 19.7 and 19.3 percent), while moisture of the same muscles was higher in wool lambs (75.6 and 75.9 vs. 73.6 and 74.3 percent). Ash content was similar in both phenotypes, but palmitoleic acid was greater in hair lambs (2.9 and 2.7 vs. 2.7 and 2.5 percent). In fresh meat, pH, meat toughness, and water activity (Wa) of loin did not differ; but water holding capacity (WHC) was higher in hair lambs, and the same response was observed for cooked meat toughness from the neck, and in raw and cooked meat from loin. There were differences in the colour of meat from the neck, having values for L*, b* and tonalities greater in wool lambs, and a* greater for hair lambs. Sensorial parameters were similar in both phenotypes.

Vinte cordeiros deslanados (Pelibuey x Katadin x BlackBelly) e 20 cordeiros lanados (Rambouillet x Criollo) foram mantidos em um sistema intensivo de alimentação até atingirem 40kg, aos 10 meses de idade. O rendimento de carcaça e a espessura da gordura foram maiores nos cordeiros lanados (51,9 por cento, 2,5mm vs. 47,0 por cento, 2,3mm). Não houve diferenças entre os dois grupos de cordeiros para pH, mas a temperatura da carne foi mais alta durante as primeiras horas pós-morte, nas meias-carcaças dos cordeiros lanados (27, 23, 20 vs. 24, 20, 17ºC). O conteúdo proteico da carne do pescoço (músculos braquicefálico e esternocefálico) e do lombo (músculo Longissimus lumborum) foi maior nos cordeiros deslanados (21,1 e 20,4 vs. 19,7 e 19,3 por cento) enquanto o teor de umidade foi maior nas lanados (75,6 e 75,9 vs 73,6 e 74,3 por cento). O conteúdo de cinzas não diferiu entre os dois grupos de cordeiros, mas o ácido palmitoleico foi maior nos cordeiros deslanados (2,9 e 2,7 vs 2,7 e 2,5 por cento). Na carne fresca, o pH, a maciez da carne e a atividade da água (Wa) do lombo não diferiram entre os grupos, mas a capacidade de retenção de água (WHc) foi maior nos cordeiros deslanados, e a mesma resposta foi observada para a maciez da carne cozida do pescoço e do lombo fresco e cozido. Houve diferenças para cor da carne do pescoço com valores de L*, b* e maior tonalidade entre os cordeiros lanados, e maior a* para os deslanados. Os parâmetros sensoriais foram semelhantes nos dois grupos.

[Descriptive epidemiology of malignant tumors in children]. / Epidemiología descriptiva de las neoplasias malignas en niños.

The object of this study is to present the descriptive epidemiology of cancer in children at the world and national levels. The international and national literature published on cancer in children was comprehensively reviewed, with emphasis on reports treating epidemiological aspects of time, place and person. For practical reasons and with the aim of integrating the information, only the more relevant publications were included. Incidence and child mortality were analyzed. Overall incidence is between 100 and 150 (annual rates = cases x 10(6) children). Specific incidence varies according to the type of cancer, the region and the country. The Latin American pattern of neoplasms is constituted by leukemias, lymphomas, and central nervous system tumors (CNST); in the Northamerican/European pattern the CNST appear in second place and in the African pattern, lymphomas show predominance. Incidence is higher among the younger than 5 year olds, from urban environments, and there is a 1% annual increase of cancer in Northamerican children. Child mortality has diminished remarkably, mainly in developed countries, whereas in developing or underdeveloped countries, incidence remains stable or shows a slight fall. The incidence of cancer in children is greater in developed countries, but in underdeveloped countries it may be underestimated. These countries have not managed to reduce the incidence of child mortality caused by cancer, as have the United States or Great Britain. Further studies on the epidemiology of cancer in children are necessary, since many data remain unknown.