Home About us Contact
|
Home About us Contact | ||
|
|
||
Tannin Level (tannin + level)
Selected AbstractsEffect of malt pretreatment on phytate and tannin level of two sorghum (Sorghum bicolor) cultivarsINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 10 2006Wisal H. Idris Summary The seeds of two cultivars of Sudanese sorghum (Sorghum bicolor), namely Wad Ahmed and Tabat, were germinated for 4 days to obtain 1-, 2- and 4-day-old malts. Sorghum malt (5% and 10%) was added to sorghum flour. The mixtures were incubated at 30 °C with shaking for 30, 60, 90 and 120 min. Malting loss was very slight for both cultivars and for all incubation periods. Phytic acid and tannin contents were assayed for all treatments. The results revealed that phytate and tannin contents were significantly (P , 0.05) reduced when sorghum flour was pretreated with malt. When a mixture containing 10%, 4-day-old malt and sorghum flour was incubated for 120 min, it significantly (P , 0.05) reduced phytate and tannin contents by 92% and 98%, respectively, for Wad Ahmed cultivar, while for Tabat they were reduced by 93% and 96%, respectively. The rate of reduction of phytate and tannin content increased with incubation time and malt age and concentration. [source] Intestinal function and body growth of broiler chickens on maize-based diets supplemented with mimosa tannins and a microbial enzymeJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 12 2004Paul A Iji Abstract A study was conducted to evaluate the effects of tannin (0, 5, 15, 20 and 25 g kg,1 diet) and a microbial enzyme supplement (MES) on the feed consumption, body growth and digestive physiology of broiler chickens between hatch and 22 days of age. Feed intake, body weight and body weight gain declined (p < 0.001) with an increase in dietary tannin content. Feed conversion efficiency was increased (p < 0.001) in line with dietary tannin level, up to 15 g kg,1 diet. There were no significant effects of dietary treatment on the protein content of pancreatic tissue or activities of pancreatic and jejunal enzymes. The ileal digestibilities of energy, protein, arginine, alanine and leucine were reduced (p < 0.001) as dietary tannin level rose to 20 g kg,1 diet and beyond. The digestibilities of methionine and phenylalanine were also negatively affected (p < 0.01) at the highest level of dietary tannins, while phosphorus digestion was improved (p < 0.05) on diets containing tannin. Apart from an increase (p < 0.01) in the protein content of the jejunal mucosa of birds on the diet with 20 g tannin kg,1 diet, there were no significant effects of the MES on most of the variables assessed. The results demonstrate the negative effects of tannin, especially at high levels of inclusion in the diet. However, neither tannins nor MES influenced the activities of digestive enzymes assessed, suggesting that a wider range of factors may be involved in regulating the effects of tannins on poultry. Copyright © 2004 Society of Chemical Industry [source] Species-specific differences in oak foliage affect preference and performance of gypsy moth caterpillarsENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 2 2003L. K. Foss Abstract The gypsy moth, Lymantria dispar (L.) (Lepidoptera: Lymantriidae), is an introduced defoliator that preferentially feeds on oaks, Quercus spp. (Fagaceae) in the north-eastern USA. As the gypsy moth expands its geographic range, the extensive oak component in forests and urban environments of the USA assure its successful establishment. Given their economic and ecological importance, and the gypsy moth's potential to cause mortality, we evaluated caterpillar preference and performance on various oaks prevalent in the central hardwoods region. Most of the physical and chemical characteristics we measured, from budbreak phenology to foliar chemistry, varied significantly among the oak species tested. Similarly, insect preference and performance varied significantly, though not always in predictable ways. Caterpillar preference was compared for black, Q. velutina Lamarck, burr, Q. macrocarpa Michaux, cherrybark, Q. pagoda Rafinesque, northern red, Q. rubra L., pin, Q. palustris Muenchhausen, swamp white, Q. bicolor Willdenow, white, Q. alba L., and willow, Q. phellos L., oaks. Gypsy moth preference was greatest for black and burr, and least for northern red, pin, and willow oaks. We assessed foliar characteristics and caterpillar performance on foliage from burr, cherrybark, northern red, pin, and willow oaks. Caterpillar preference did not always correlate with performance. Gypsy moth consumption and growth were highest, and development most rapid, on pin oak, which had high nitrogen and tannin levels, and was among the least preferred. Northern red and willow oaks were also among the least preferred and were the least suitable tested, producing caterpillars with moderate to low consumption and growth rates, as well as the longest development. Northern red oak contained the lowest foliar tannins; willow oak foliage was lowest in carbohydrates and nitrogen. Our results suggest that a combination of foliar characteristics may be responsible for gypsy moth preference and performance, and that an optimal combination of foliar components serves to maximize host suitability. These data will provide information useful for planning and managing urban forests in the presence of expanding gypsy moth populations. [source] Implications of closed ecosystem conservation management: the decline of Rothschild's giraffe (Giraffa camelopardalis rothschildi) in Lake Nakuru National Park, KenyaAFRICAN JOURNAL OF ECOLOGY, Issue 4 2009Rick A. Brenneman Abstract Giraffe were historically free-ranging across most of sub-Saharan Africa but are now most often confined to national parks, conservation areas, or private ranches. Five viable populations of Rothschild's giraffe (Giraffa camelopardalis rothschildi) remain in protected areas in Kenya and Uganda. The viable population in Uganda is Murchison Falls National Park and the four populations in Kenya are Lake Nakuru National Park (LNNP), Ruma National Park, Giraffe Manor, and Mwea Natural Reserve. The Kenya Wildlife Service queried a rapid decline in LNNP giraffe numbers falling from 153 individuals (1995) to 62 individuals (2002) and the failure of that population to recruit young in those years. Significantly reduced browse options, inbreeding depression and preferential lion predation were considered as potential reasons for this trend. Population genetic parameter estimates derived from multilocus genotype analyses suggest that the LNNP population was in good genetic health with respect to the likelihood of inbreeding depression. The population decline coincided with the drought attributed to the 1994 El Niño. Possible dietary complications from highly concentrated tannin levels because of forced over consumption of the park's declining acacia trees may have compromised young giraffe, making them easy and opportunistic prey for the park's lion population. Résumé Dans le passé, des girafes évoluaient librement dans une grande partie de l'Afrique sub-saharienne, mais elles sont désormais confinées le plus souvent dans des parcs nationaux, des aires de conservation ou des ranches privés. Cinq populations viables de girafes de Rothschild (Giraffa camelopardalis rothschildi) subsistent dans des aires protégées au Kenya et en Ouganda. La population viable d'Ouganda est celle du Parc National des Murchison Falls, et les quatre populations du Kenya sont celles du Parc National du Lac Nakuru (LNNP), du Parc National de Ruma, du Giraffe Manor et de la Réserve Naturelle de Mwea. Le Kenya Wildlife Service s'est interrogé au sujet du déclin rapide du nombre de girafes au LNNP qui est passé de 153 individus en 1995 à 62 en 2002, et de l'échec de cette population pour recruter des jeunes ces années-là. Des possibilités alimentaires réduites, une dépression due à l'inbreeding, et une prédation préférentielle par les lions ont été envisagées comme raisons de cette tendance. Des estimations des paramètres génétiques de la population dérivées d'analyses de génotypes multilocus suggèrent que la population du LNNP est en bonne santé génétique en ce qui concerne la possibilité de dépression causée par l'inbreeding. Le déclin de la population a coïncidé avec la sécheresse attribuée à El Niño en 1994. Il est possible qu'elle ait souffert de complications alimentaires à cause de taux de tanins très concentrés, parce qu'elle a été forcée de consommer à l'excès les acacias du parc, qui sont en déclin, et que ces complications aient nui aux jeunes girafes et aient fait d'elles des proies faciles pour la population opportuniste des lions du parc. [source] | |||||||||||||