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Dietary Items (dietary + item)
Selected AbstractsHow do small browsers respond to resource changes?FUNCTIONAL ECOLOGY, Issue 3 2010Dietary response of the Cape grysbok to clearing alien Acacias Summary 1.,The responses of small ruminants to changing food availability may vary from a broadening of the diet with declining availability, as predicted by optimality theory, to the maintenance of a restricted, selected diet, as predicted by the body-size constraint hypothesis. 2.,We test these conflicting predictions by assessing the dietary responses of the Cape grysbok Raphicerus melanotis, a near-endemic to the Cape Floristic region, South Africa, to changes in the availability of a key forage species (i.e. Australian Acacia sp.). We predicted that the removal of alien Acacias would cause a broadening of the diet, and the consumption of previously avoided species, despite the selectivity imposed by their small body size. We used faecal analyses to describe grysbok diet and assessed diet quality through faecal quality analyses. 3.,Results show that grysbok are highly selective browsers, able to change their diet and dietary preferences in response to changes in food availability. Animals included additional species in the diet in the absence of alien Acacias, altered their principal dietary items, broadened foraging strategies to include grass and some previously avoided species became preferred in the absence of Acacias. These dietary changes were effective in maintaining dietary protein intake, and caused a reduction in fibre intake in the absence of Acacias. 4.,The data do not support the body size constraint hypothesis which is thought to impose a limit on the ability of small ruminants to select additional dietary species. 5.,These data represent the first quantification of extensive grazing (up to 51% of the diet) by a species considered a browser. These findings support the prediction of optimality theory, whereby animals faced with a loss of important food items broaden their diet to include previously avoided species. [source] Seasonal variation in forages utilized by the African buffalo (Syncerus caffer) in the succulent thicket of South AfricaAFRICAN JOURNAL OF ECOLOGY, Issue 2 2010Thulani Tshabalala Abstract The succulent thicket of the Eastern Cape, South Africa, is characterized by densely wooded vegetation that is dominated by succulents with little understory of ephemeral and weakly perennial grasses and forbs. Studies have developed around the question: how do bulk grazers such as the African buffalo (Syncerus caffer) survive in the succulent thicket? In this study, the diet of the African buffalo at the Great Fish River Reserve (GFRR) was studied in two seasons (wet and dry). The diet profile was assessed from faecal matter, using the micro-histological analysis method. During the wet season, grass species contributed 72% to the diet while 28% was contributed by browse species. In the dry season there was a significant increase in the intake of browse by 5% (,2 = 19.94, df = 11, P < 0.05). There were species that were neglected in the wet season but became principal dietary items in the dry season, these included Setaria neglecta, Cymbopogon plurinodis, Capparis sepiaria and Portulacaria afra. Diet quality, as estimated from faecal samples, suggested that the buffalo were nutritionally stable; however, the presence of sarcoptic mange in the buffalo suggests nutritional stress. Résumé Le fourré de plantes succulentes de l'Eastern Cape, en Afrique du Sud, se caractérise par une végétation boisée dense dominée par des succulentes avec un peu de sous-bois d'herbes éphémères ou faiblement pérennes. Des études se sont développées au départ de cette question: comment des gros ruminants comme le buffle (Syncerus caffer) peuvent-ils survivre dans le fourré de succulentes ? Dans cette étude, nous avons étudié pendant deux saisons (des pluies et sèche) le régime alimentaire du buffle de la Great Fish River Reserve (GFRR). On a évalué le profil du régime à partir de la matière fécale, en utilisant la méthode de l'analyse micro-histologique. Pendant la saison des pluies, les monocotylédones composaient 72% du régime et les 28% restants étaient composés d'espèces de brout. En saison sèche, il y avait une augmentation significative (5%) des espèces de brout (X²= 19,94, d.f = 11, P < 0,05). Il y avait des espèces qui étaient négligées en saison des pluies mais qui devenaient des éléments principaux du régime en saison sèche. Parmi ceux-ci, citons Setaria neglecta, Cymbopogon plurinodis, Capparis sepiaria et Portulacaria afra. La qualité du régime alimentaire, estimée d'après les matières fécales, suggère que les buffles sont stables au point de vue nutritionnel; toutefois, la présence de gale sarcoptique chez les buffles suggère un stress alimentaire. [source] PHYSICOCHEMICAL AND PROCESSING FUNCTIONAL PROPERTIES OF PROTEINS FROM TWO CHINESE CHICKPEA (CICER ARIETINUM L.) CULTIVARSJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 4 2010WEN-RUI GAO ABSTRACT The physicochemical and functional properties of protein isolates from two Chinese chickpea cultivars were investigated and compared with those of SPI. GCPI has the lightest, reddest, most yellow and highest chroma. SHF and Ho of three protein isolates were significantly different (P < 0.05). Significant differences (P < 0.05) in EAI, FC, FS and LGC were observed between the two chickpea protein isolates, whose most functional properties were inferior to those of SPI. Most textural properties of heated gels from two chickpea protein isolates were similar and were also inferior to those of the SPI heated gel. PRACTICAL APPLICATIONS Chickpea is the third most widely grown grain legume crop in the world after bean and soybean. In the present study, we examined the physicochemical properties (chemical composition, color characteristics, SHF content and Ho) and functional properties (nitrogen solubility, emulsifying properties, WHC and OHC, FC and FS, and gelation properties) of protein isolates derived from Desi and Kabuli chickpea cultivars grown in Xinjiang Autonomous Region in China, and compared them with those of SPI. This study would be useful in the comprehensive understanding of the characteristics of chickpea protein and its use as a potential additive for food and dietary items. [source] Linkages between household wealth, bushmeat and other animal protein consumption are not invariant: evidence from Rio Muni, Equatorial GuineaANIMAL CONSERVATION, Issue 6 2009J. E. Fa Abstract Bushmeat consumption is affected by household wealth. However, how household wealth impacts bushmeat eaten in different environmental and social settings (i.e. whether urban, rural, coastal or forest) is poorly understood. In this study, we sampled households in six contrasting localities in Rio Muni, Equatorial Guinea, in coastal (Bata, Cogo), central (Niefang, Evinayong) and eastern parts of the territory (Ebebiyin, Nsork). On average, 32.3 g of bushmeat per adult male equivalent per day were consumed, though this varied widely between sites and most households ate no bushmeat on the survey day. Fish was the most frequently recorded source of protein and in a coastal site, Cogo, significantly more fish was consumed than in the other localities. Overall, average protein consumption was correlated with household wealth, but the strength of this effect varied among sites. At the site where average wealth was highest (Bata, the most urban site), bushmeat was more expensive, and wealthier households ate more of it. Elsewhere bushmeat consumption was not associated with wealth, and the cost of bushmeat was a higher proportion of household wealth. In Bata, wealthier households reported consumption of more than one meat type (most frequently bushmeat and either domestic meat or fish), and diversity of dietary items also increased with wealth. In all sites, wealthier households ate less fish. We demonstrate distinct differences in relationships between urban versus rural areas, and between coastal versus inland sites. We therefore caution that general patterns of wealth,wild meat consumption must be evaluated taking account the circumstances of wild meat consumers. [source] Morphological correlates of ant eating in horned lizards (Phrynosoma)BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2006JAY J. MEYERS The North American horned lizards (Phrynosoma) represent a morphologically specialized group of ant-eating lizards. Although variation in dietary fidelity is observed among the species, all appear to possess morphological specializations thought to be related to their ant-eating diets. Previous studies have examined morphological specialization in Phrynosoma, but they have not taken into account the phylogenetic relationships of its member species. In the present study, the morphological characteristics of the head, jaws and teeth that are thought to be important in prey capture and prey processing were examined to test whether variation in cranial morphology is associated with diet in lizards of the genus Phrynosoma. It is suggested that lizards of the genus Phrynosoma are indeed morphologically specialized and that ant-eating is associated with reduced dentition and an overall reduction in the robustness of morphological structures important in prey processing. Although this trend holds for the highly myrmecophagous species of Phrynosoma, a robust cranial morphology is apparent in the short-horned lizard clade (Phrynosoma ditmarsi, Phrynosoma douglasii, Phrynosoma hernandesi, Phrynosoma orbiculare), implying the ability to process a variety of dietary items. The present study suggests that additional feeding specializations exist within an already specialized clade (i.e. the short-horned lizard clade) and highlights the need for more detailed dietary and behavioural studies of feeding behaviour in this uniquely specialized group of lizards. © 2006 The Linnean Society of London, Biological Journal of the Linnean Society, 2006, 89, 13,24. [source] | ||||||||||