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The aim of the present study was to define whether elevated rumen-undegradable protein (RUP) and tannin-rich peanut skin (PS) supplementation would affect animal growth performance, average daily gain (ADG), blood metabolites, carcass traits associated with lipogenic and immune-related gene expressions in meat goats grazing winter wheat (WW). Thirty-six Kiko-crossbreed male goats at approximately 6 months of age were blocked by body weight (BW; 25.6 ± 1.1 kg) and randomly assigned to one of the four treatments with two replicates based on a 2 × 2 factorial design. Diets contained PS replacing alfalfa meal (ALM), without or with RUP supplementation. Both PS and ALM were incorporated into grain mix portion of the diet and pelletized, with remaining diets fed ad libitum of WW forage for a period of 51 days. Lipogenic genes examined included SCD, ACLY, YWHAZ, PPIA and FABP4, while immune-related genes examined included ACTB (as a control gene), H3F3A, PPIA, IRF3, STAT2, HERC3 and IFIT3 antibody genes. The meat goats on PS-pellet-supplemented group with or without RUP supplementation grew 38.5% faster ADG (p < .001) when compared to control-supplemented group. When goats received PS diet, empty body weight, hot carcass, cold carcass, shoulder, hind shank, rack, loin and fat thickness were greater (p < .05) than control diet. Animals on PS-pellet had higher ACLY, YWHAZ, PPIA and FABP4 gene expression (p < .05) when compared to ALM-pellet control, with RUP by PS-pellet interactions (p < .01). Goats receiving additional RUP supplementation had increased (p < .05) STAT2 gene expression, whereas goats receiving PS-pellet supplementation showed increased STAT2 (p < .05) and a tendency to increase IRF3 (p = .07) gene expressions. In conclusion, the addition of PS-pellet or RUP supplementation has the potential to improve ADG and altered selected lipogenic and immune-related gene expressions.  相似文献   
13.
Stagonospora nodorum blotch (SNB), caused by Phaeosphaeria nodorum, is a destructive disease of wheat (Triticum aestivum) found throughout the United States. Host resistance is the only economically feasible option for managing the disease; however, few SNB-resistant wheat cultivars are known to exist. In this study, we report findings from an association mapping (AM) of resistance to P. nodorum in 567 spring wheat landraces of diverse geographic origin. The accessions were evaluated for seedling resistance to P. nodorum in a greenhouse. Phenotypic data and 625 polymorphic diversity array technology (DArT) markers have been used for linkage disequilibrium (LD) and association analyses. The results showed that seven DArT markers on five chromosomes (2D, 3B, 5B, 6A, and 7A) were significantly associated with resistance to P. nodorum. Genetic regions on 2D, 3B, and 5B correspond to previously mapped quantitative trait loci (QTL) conferring resistance to P. nodorum whereas the remaining QTL appeared to be novel. These results demonstrate that the use of AM is an effective method for identifying new genomic regions associated with resistance to P. nodorum in spring wheat landraces. Additionally, the novel resistance found in this study could be useful in wheat breeding aimed at controlling SNB.  相似文献   
14.
Biosynthesis of the oxylipin jasmonic acid (JA) in Arabidopsis thaliana is catalyzed by a single allene oxide synthase (AOS)-encoding gene and four genes encoding four functional allene oxide cyclase (AOC) polypeptides (AOC1, AOC2, AOC3, and AOC4). To elucidate the biological activities of the JA pathway in regulating the plant defense response to plant-parasitic nematodes, transgenic lines carrying the GUS reporter gene under the control of individual AOC or AOS promoters were examined. Upon penetration by second-stage juveniles (J2 s), promoter activities of AOC1, AOC3 and AOC4 appeared in the root tip and root-elongation zone, with AOC3 demonstrating highest induction. At 5 days AOC3 activity continued to be highly pronounced in the stele and root cortex, associated with nematode invasion throughout gall initiation and maturation. AOS expression appeared 3 days postinfection and accompanied all later infection stages. Mutant lines were analyzed: disruption in AOS rendered plants more resistant to nematode infection, as reflected by the decreased number of females produced on this line; loss-of-function of AOC3 rendered plants more susceptible to nematode infection. Oxylipins derived from the 9- and 13-lipoxygenase pathways were assayed for their direct inhibitory activity toward M. javanica J2 s. Clear nematicidal activity of the bioactive 9- and 13-hydroperoxides was observed. Oxylipins produced by divinyl ether synthase, colneleic acid, colnelenic acid and ω5(Z)-etherolenic acid demonstrated strong inhibitory activity. These data, along with those of other assayed oxylipins, suggest that temporal and spatial fine tuning of the JA route allowing nematodes parasitism on plant host.  相似文献   
15.
Bacterial leaf streak (BLS), caused by Xanthomonas translucens pv. undulosa, has become more prevalent recently in North Dakota and neighboring states. From five locations in North Dakota, 226 strains of X. translucens pv. undulosa were collected and evaluated for pathogenicity and then selected strains were inoculated on a set of 12 wheat cultivars and other cereal hosts. The genetic diversity of all strains was determined using repetitive sequence-based polymerase chain reaction (rep-PCR) and insertion sequence-based (IS)-PCR. Bacterial strains were pathogenic on wheat and barley but symptom severity was greatest on wheat. Strains varied greatly in aggressiveness, and wheat cultivars also showed differential responses to several strains. The 16S ribosomal DNA sequences of the strains were identical, and distinct from those of the other Xanthomonas pathovars. Combined rep-PCR and IS-PCR data produced 213 haplotypes. Similar haplotypes were detected in more than one location. Although diversity was greatest (≈92%) among individuals within a location, statistically significant (P ≤ 0.001 or 0.05) genetic differentiation among locations was estimated, indicating geographic differentiation between pathogen populations. The results of this study provide information on the pathogen diversity in North Dakota, which will be useful to better identify and characterize resistant germplasm.  相似文献   
16.
The objective of this experiment was to determine the effects of feeding varying levels of crude glycerine (CG) on dry matter intake (DMI), animal performance, carcass traits and rumen volatile fatty acids (VFA) concentration in meat goats. Twenty-four intact male Boer goats (23.9 ± 1.0 kg initial BW and 4–5 months of age) were randomly assigned to one of four experimental diets (n = 6) containing 30% bermudagrass hay plus 70% concentrate mix with 0, 5, 10 or 15% CG in the diet on an as-fed basis, substituted for the corn portion of the concentrate. Feed offered and refusals were monitored daily for 84 days. Goats were weighed at 28-days interval. Blood and rumen samples were collected on day 84. At the end of the 84-days feeding period, goats were harvested, and carcass characteristics measured. Feed intake, average daily gain (ADG), gain-to-feed ratio (G:F), carcass traits and VFA concentrations were analysed as a completely randomized design. The CG did not influence animal body weight (BW) changes, ADG and G:F ratio but tended to (p = 0.06) decrease DMI. Molar per cent propionic acid increased linearly (p < 0.05) with increasing CG. The acetate: propionate (A:P) ratio decreased (p < 0.05) with increasing amounts of CG in the diet. The CG addition tended to increase (p = 0.09) the longissimus muscle (LM area) in meat goats. In conclusion, CG can replace corn in diet for growing meat goats when fed up to 15% of diet, improving ruminal propionate concentration, but decreasing A:P ratio without affecting animal performance and carcass traits.  相似文献   
17.
The status of forest conditions before and after intervention of the forestry projects in community forest in three districts of Nepal is examined. Benefits are observed from the adoption of adaptive collaborative management and collective learning and action research in three sampled districts. The adoption of regular silvicultural treatments has increased the availability of forest products to local users. Moreover, improved forest condition and smallholder livelihoods have improved, as has environmental sustainability. However, the community forestry program has several limitations and shortcomings. Elite capture, social disparity, inequitable benefit-sharing and exclusion of poor and marginalized groups from the community forestry program are notable challenges to be solved in coming years. Special attention is needed to make community forestry inclusive with equitable benefit-sharing and a pro-poor focus.  相似文献   
18.
Twenty-two Kiko crossbred male goats (Capra hircus; initial BW = 27.5 ± 1.04 kg) were used in a randomized complete block design to determine the effects of feeding pine bark (PB; Pinus taeda L.) on animal performance, rumen fermentation, blood parameters, fecal egg counts (FEC), and carcass characteristics in goats. Experimental treatments included the control diet [0% PB plus 30% wheat straw (WS)], 15% PB plus 15% WS, and 30% PB plus 0% WS (on as-fed basis), where PB replaced WS. Freshly air-dried PB and WS were finely (1.5 to 3.0 mm) ground and incorporated in the grain mixes. Experimental diets provided a total of 1.9, 16.3, and 32 g of condense tannins (CT)/kg DM in 0%, 15%, and 30% PB diets, respectively. The grain mixes were fed daily at 85% of the feed offered, with remaining 15% consisting of Bermuda grass hay (Cynodon dactylon). Animals were fed once a day at 0800 h, and feed offered and refused was monitored for an 83-d performance period. Rumen and blood samples were collected at d 0, 50, and 80 of the study. Carcass traits were assessed after slaughter at the end of performance period. There was no difference in initial BW, hay, and total NDF intake among treatments; however, final BW (P = 0.06), ADG (P < 0.01), grain mix intake (P < 0.001), total DMI (P < 0.001), and G:F (P < 0.04) increased linearly as the PB increased in the diets. Rumen ammonia N, acetate, isovalerate and acetate-to-propionate ratio were reduced linearly (P < 0.05). There was no difference in carcass traits except cold carcass weight (P = 0.06), which tended to increase linearly in goats fed 15% and 30% PB. Breast, sirloin, trim trait, liver, and hide weight increased (linear; P < 0.01) with addition of PB. Blood basophils, alanine transaminase, aspartate aminotransferase, albumin, Na, and Cl concentrations decreased (linear; P < 0.02 to 0.01) as PB supplementation increased. Supplementation of PB reduced (linear; P < 0.01) average FEC. Addition of PB in the diets improved performance, reduced FEC, and favorably modified rumen fermentation.  相似文献   
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The national maize improvement program in Nepal regularly receives elite maize (Zea mays L.) genotypes from CIMMYT and other countries and tests them for their performance stability in highly diverse environments. Studies were conducted on research stations and farmers’ fields at five sites in three years to determine performance stability of exotic maize genotypes. Replicated on-station and on-farm studies were conducted using 25 and 10 genotypes, respectively, including a local check and an improved check (Manakamana-3), in 2004–2006. We analyzed grain yield, days to flowering, plant and ear height, plant population, husk cover, and plant and ear aspect. Stability and genotype superiority for grain yield was determined using genotype and genotype × environment (GGE) biplot analysis that compares among a set of genotypes with a reference ‘ideal’ genotype, which has the highest average value of all genotypes and is absolutely stable. Several genotypes produced significantly higher grain yield than the local check. Four genotypes (‘Across9942 × Across9944’, ‘Open Ended White Hill Population’, ‘Population 44C10’ and ‘ZM621’), that produced significantly higher grain yield than the improved check, also had other agronomic traits (days to flowering, plant and ear height, number of ears, resistance to leaf blight, plant and ear aspect and husk cover tightness) equal to or better than the improved check. GGE-biplot analysis showed that Across9942 × Across9944 and ZM621 were the most superior genotypes in the on-station and on-farm trials, respectively. The findings from this study provide new information on the stability of the maize genotypes that are also adapted to other regions of the world. Such information could be useful for maize improvement program for the highlands in Nepal and other similar environments.  相似文献   
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