Donkey （Equus asinus） domesticated animal, is neglected as an object of scientific study. In countries where donkeys are used for work, they are slaughtered at the end of their useful working life and meat is destin...Donkey （Equus asinus） domesticated animal, is neglected as an object of scientific study. In countries where donkeys are used for work, they are slaughtered at the end of their useful working life and meat is destined for human consumption. This study was carried out to evaluate the mineral composition of donkey carcass meat. Meat was obtained in Donkey Fair 2016 at Mexico State, minerals were analyzed by Atomic Absorption Spectxophotometry, Ca, Na, K, Fe, Zn and Cu, and P content by colorimetry. Data obtained in mg/100g were： Ca, 7.95; Na, 48.75; K, 353; Fe, 3,95; Zn, 3.17; Cu, 0.19 and P, 227. Analysis revealed that donkey meat has a low content of Ca, but it is good in P as well as K. In conclusion donkey meat is a good source of minerals requested for human health.展开更多
In nature hummingbirds face floral resources whose availability, quality and quantity can vary spatially and temporally. Thus, they must constantly make foraging decisions about which patches, plants and flowers to vi...In nature hummingbirds face floral resources whose availability, quality and quantity can vary spatially and temporally. Thus, they must constantly make foraging decisions about which patches, plants and flowers to visit, partly as a function of the nectar reward. The uncertainty of these decisions would possibly be reduced if an individual could remember locations or use visual cues to avoid revisiting recently depleted flowers. In the present study, we carried out field experiments with white-eared hummingbirds Hylocharis leucotis, to evaluate their use of locations or visual cues when foraging on natural flowers Penstemon roseus. We evaluated the use of spatial memory by observing birds while they were foraging between two plants and within a single plant. Our results showed that hummingbirds prefer to use location when foraging in two plants, but they also use visual cues to efficiently locate unvisited rewarded flowers when they feed on a single plant. However, in absence of visual cues, in both experiments birds mainly used the location of previously visited flowers to make subsequent visits. Our data suggest that hummingbirds are capable of learning and employing this flexibility depending on the faced environmental conditions and the information acquired in previous visits [Current Zoology 57 （4）： 468-476, 2011].展开更多
文摘Donkey （Equus asinus） domesticated animal, is neglected as an object of scientific study. In countries where donkeys are used for work, they are slaughtered at the end of their useful working life and meat is destined for human consumption. This study was carried out to evaluate the mineral composition of donkey carcass meat. Meat was obtained in Donkey Fair 2016 at Mexico State, minerals were analyzed by Atomic Absorption Spectxophotometry, Ca, Na, K, Fe, Zn and Cu, and P content by colorimetry. Data obtained in mg/100g were： Ca, 7.95; Na, 48.75; K, 353; Fe, 3,95; Zn, 3.17; Cu, 0.19 and P, 227. Analysis revealed that donkey meat has a low content of Ca, but it is good in P as well as K. In conclusion donkey meat is a good source of minerals requested for human health.
文摘In nature hummingbirds face floral resources whose availability, quality and quantity can vary spatially and temporally. Thus, they must constantly make foraging decisions about which patches, plants and flowers to visit, partly as a function of the nectar reward. The uncertainty of these decisions would possibly be reduced if an individual could remember locations or use visual cues to avoid revisiting recently depleted flowers. In the present study, we carried out field experiments with white-eared hummingbirds Hylocharis leucotis, to evaluate their use of locations or visual cues when foraging on natural flowers Penstemon roseus. We evaluated the use of spatial memory by observing birds while they were foraging between two plants and within a single plant. Our results showed that hummingbirds prefer to use location when foraging in two plants, but they also use visual cues to efficiently locate unvisited rewarded flowers when they feed on a single plant. However, in absence of visual cues, in both experiments birds mainly used the location of previously visited flowers to make subsequent visits. Our data suggest that hummingbirds are capable of learning and employing this flexibility depending on the faced environmental conditions and the information acquired in previous visits [Current Zoology 57 （4）： 468-476, 2011].
