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By electrophoresis it became obvious that larvae of Hypoderma bovis are able to take up complete proteins from their host's serum directly into the haemolymphe, fatbody and ovarium. This could be proved by experiments with radioactive albumin. [ABSTRACT FROM AUTHOR]

Bears in the wild spend large proportions of time in foraging activities. In zoos their time budgets differ markedly from those of their wild counterparts. Feeding enrichment has been documented to increase foraging behavior and to reduce stereotypies. But in general these procedures have no long-term effects and result in habituation. As can be expected by the predictions of the optimal foraging theory, foraging activities are restricted as long as the availability of food is predictable. To quantify the effect of spatial unpredictability, three feeding methods have been designed to stimulate functional foraging behavior in captive Malayan sun bears in the long-term. In order to examine if habituation occurs, the most effective method was tested for 12 consecutive days. Activities of four adult sun bears at the Cologne Zoo were recorded by focal animal recording of foraging behaviors and time sampling of activities for a total of 360 hr. Implementing unpredictability significantly increased the time the bears spent foraging and led to a higher diversity of foraging behaviors. The effects lasted throughout the entire day and no habituation occurred in the course of 12 consecutive days. The study shows how functional species typical behavior in captive Malayan sun bears can be stimulated in the long-term by simulating natural characteristics of food availability., (© 2014 Wiley Periodicals, Inc.)

Sauropod dinosaurs, the dominant herbivores throughout the Jurassic, challenge general rules of large vertebrate herbivory. With body weights surpassing those of any other megaherbivore, they relied almost exclusively on pre-angiosperm plants such as gymnosperms, ferns and fern allies as food sources, plant groups that are generally believed to be of very low nutritional quality. However, the nutritive value of these taxa is virtually unknown, despite their importance in the reconstruction of the ecology of Mesozoic herbivores. Using a feed evaluation test for extant herbivores, we show that the energy content of horsetails and of certain conifers and ferns is at a level comparable to extant browse. Based on our experimental results, plants such as Equisetum, Araucaria, Ginkgo and Angiopteris would have formed a major part of sauropod diets, while cycads, tree ferns and podocarp conifers would have been poor sources of energy. Energy-rich but slow-fermenting Araucaria, which was globally distributed in the Jurassic, was probably targeted by giant, high-browsing sauropods with their presumably very long ingesta retention times. Our data make possible a more realistic calculation of the daily food intake of an individual sauropod and improve our understanding of how large herbivorous dinosaurs could have flourished in pre-angiosperm ecosystems.

At the end of their migration larvae of Hypoderma bovis have reached about 42% of their final length, but only 10% of their final body-weight. Oxygenium-consum/mg body-weight decreased during the larval development: a larva of 50 mg weight needs 800 mm 3 /mg·h, one of 1500 mg weight only 100 mm 3 /mg·h. Third instar larvae have a much higher oxygenium-consum after moulting than second instar larvae have just before. The relation of oxygenium-consum/body-weight differs in the two larval stages. Respiration depends on the temperature, its maximum is between 32°C and 37°C. Young animals have a higher maximum than old ones.