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991.
The pH of precipitation, and the concentrations in precipitation and depositions by precipitation of H+, major cations, N, S, and chloride were measured in bulk collectors at three sites in Eastern England. The Rothamsted site is 100 km from the coast in a semi-urban environment. The Saxmundham site is 13 km and the Woburn site 120 km from the coast; both are in rural environments. Precipitation is acidic at all three sites, with a pH of 4.3 at Rothamsted and 5.0 at Saxmundham and Woburn at present, but the pH has been increasing. Precipitation chemistry is chiefly controlled by sea-salts (Na, Mg, Cl) and earth salts (K, Ca, Mg, NH4, N03). Sea-salts dominate near the coast at Saxmundham, but earth salts become much more important inland at Rothamsted and at Woburn. The concentration and deposition of non-sea Cl are increasing at Rothamsted and Saxmundham, those of non-sea SO4-S are increasing at Woburn, and those of NO3-N are increasing at all of the sites. Precipitation acidity is associated chiefly with non-sea SO4, and only a little with NO3 and non-sea Cl, at Rothamsted and Woburn. At Saxmundham, no correlation between acidity and anions is observed, presumably because of the overwhelming effect of sea-salts.  相似文献   
992.
Hull thickness is an important component of seed quality, which effects dehulling ability, feed or food nutritional aspects and cooking times. A breeding objective in Lupinus angustifolius crop improvement is to reduce hull thickness and a rapid screening method is needed to efficiently screen genotypes. Optical coherence tomography (OCT) imaging using infrared illumination at 980 nm was used to compare hull thickness of genotypes of four lupin species. OCT‐derived hull layer thickness correlated highly with actual hull thickness determined by environmental scanning electron microscopy (r = 0.90) and allowed reliable distinction between mutant (thin‐hulled) and parent genotypes of L. angustifolius. The imaging could clearly penetrate lupin seed to a depth of approximately 200 μm. The use of OCT to measure hull thickness has the advantage that it is rapid and non‐destructive and should be very useful in selecting thin hull lines of lupins and other species on a single seed basis in germplasm or progeny from crosses.  相似文献   
993.
N. C. Oraguzie    T. Yamamoto    J. Soejima    T. Suzuki  H. N. De  Silva 《Plant Breeding》2005,124(2):197-202
Identification of apple clonal rootstocks based on visual morphological characteristics is often difficult because of the genetic similarity of many rootstocks and the restriction of observable characteristics at the nursery stage. In this study, a total of 66 rootstock clones representing a sub‐sample of a collection of apple rootstocks from different countries maintained at NIFTS, Morioka, Japan, was screened with seven simple sequence repeat (SSR) markers to establish genetic identities, estimate genetic diversity, verify parentage and examine genetic relationships. All seven SSR loci produced one or two amplified fragments and made it possible to differentiate among the rootstocks, except between virus‐free subclones and their original parents as well as between ‘Aotea 40’ and ‘Aotea 106’. The parentage of all but one rootstock clone was confirmed. The placement of individual rootstock clones into subgroups in a phenogram generated from un‐weighted pair group average cluster analysis was generally based on parentage or genetic origin. Based upon the ability of the SSR data to differentiate these apple rootstocks and the high level of gene diversity, it is proposed that all commercial apple rootstocks be fingerprinted to provide a mechanism to verify the identity of individual clones.  相似文献   
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This study is aimed at determining the maximum inclusion level of tamarind (Tamarindus indica) residues in the diet of goats on intake, digestibility, ingestive behavior, and nitrogen (N) balance. Twenty-four crossbred (Boer × undefined breed) castrated goat kids (5 months old and with an initial weight of 23.9?±?0.3 kg) were assigned in a completely randomized design (4 treatments and 6 replicates). Diets consisted of Tifton 85 (Cynodon sp.) hay as the roughage (400 g/kg) source and concentrate (600 g/kg); the levels of tamarind residue inclusion were 0.0, 7.0, 14.0, and 21.0% on a dry matter (DM) basis. The experimental period lasted 23 days (15 of adaptation and 8 of sampling). Inclusion of tamarind residue in the goat kid diets did not affect (P?>?0.05) the intake and digestibility of DM, crude protein, neutral detergent fiber (NDF), and total digestible nutrient; intake of N, urinary N, and retained N (g/day); time spent ruminating; numbers of times/day feeding, ruminating, or idling; eating efficiency of DM and NDF; number of boluses/day; and amount (g) of DM/bolus. However, there were a linear reduction in ether extract digestibility (P?=?0.011) and a linear decreasing trend in non-fibrous carbohydrate digestibility (P?=?0.083). The addition of tamarind residue had a positive linear effect (P?=?0.041) on the time spent feeding and promoted a decreasing linear trend for the time spent idling (P?=?0.063). It is recommended to include the residue from tamarind fruit at a level of 21% in diets for goat kids, as it does not affect nutrient intake and digestibility and the N balance.

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999.
Tropical Animal Health and Production - The increase in haylage production leads to the search for additives that improve its fermentation and nutritional value. This study aimed to assess the...  相似文献   
1000.

The present study attempted to verify the prevalence of and risk factors for diarrhea-causing agents in dairy calves from Brazil. Additionally, ages with a higher risk of occurrence for each agent were verified by means of the receiver operating characteristic (ROC) curve. The collections were performed on 39 farms, belonging to 29 municipalities located in eight states of Brazil. It was possible to conclude that the prevalence of Coronavirus, Rotavirus, Cryptosporidium spp., Eimeria spp., and nematodes was 7.20% (95% CI 4.54–9.78), 6.37% (95% CI 3.85–8.89), 51.52% (95% CI 45.26–55.57), 3.46% (95% CI 2.24–4.67), and 3.46% (95% CI 2.24–4.67), respectively. Ages with higher probabilities of occurrence of these diseases in calves were <?10, >?8, >?6, >?37, and >?36 days, respectively. Diarrhea occurred more significantly (P?<?0.0001) in animals less than 21 days old and mainly on those receiving milk through automatic feeders (P?<?0.001). Cryptosporidium spp. were a risk factor for the occurrence of Rotavirus, and vice versa (P?=?0.0039) and presented a positive correlation with Coronavirus (P?=?0.0089). Calves that drink water from rivers, streams, and ponds had a higher chance of being infected by Eimeria spp. (P?<?0.0001), as well as developing infection by nematodes (P?<?0.0001). The results found in this study highlight the importance of studying the agents of diarrhea together, once they act as coinfection where the losses triggered for the owners will involve some of these agents simultaneously.

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