Determinants of income-earning strategies and adoption of conservation practices in hillside communities in rural Honduras     

Hans G.P. Jansen  Angel Rodriguez  Amy Damon  John Pender  Jacqueline Chenier  Rob Schipper 《Agricultural Systems》2006

Based on the results of participatory diagnostic surveys conducted in 95 rural communities in the hillsides of Honduras, we determine income earning strategies at the community level; identify their main determinants; and analyze the adoption of of conservation practices. Eight income-earning strategies were distinguished that reflect differences in comparative advantage between communities. We explain the choice of income earning strategy using a multinomial logit model that includes biophysical, economic, social and institutional variables. We use a probit model to show that adoption of conservation practices is determined by the type of income earning strategy, population density, market access, and organizational variables.  相似文献   

Effect of pharmacological concentrations of zinc oxide with or without the inclusion of an antibacterial agent on nursery pig performance   总被引：4，自引：0，他引：4  

Hill GM  Mahan DC  Carter SD  Cromwell GL  Ewan RC  Harrold RL  Lewis AJ  Miller PS  Shurson GC  Veum TL;NCR- Committee on Swine Nutrition 《Journal of animal science》2001,79(4):934-941

A study involving nine research stations from the NCR-42 Swine Nutrition Committee used a total of 1,978 crossbred pigs to evaluate the effects of dietary ZnO concentrations with or without an antibacterial agent on postweaning pig performance. In Exp. 1, seven stations (IA, MI, MN, MO, NE, ND, and OH) evaluated the efficacy of ZnO when fed to nursery pigs at 0, 500, 1,000, 2,000, or 3,000 mg Zn/kg for a 28-d postweaning period. A randomized complete block experiment was conducted in 24 replicates using a total of 1,060 pigs. Pigs were bled at the 28-d period and plasma was analyzed for Zn and Cu. Because two stations weaned pigs at < 15 d (six replicates) and five stations at > 20 d (18 replicates) of age, the two sets of data were analyzed separately. The early-weaned pig group had greater (P < 0.05) gains, feed intakes, and gain:feed ratios for the 28-d postweaning period as dietary ZnO concentration increased. Later-weaned pigs also had increased (P < 0.01) gains and feed intakes as the dietary ZnO concentration increased. Responses for both weanling pig groups seemed to reach a plateau at 2,000 mg Zn/kg. Plasma Zn concentrations quadratically increased (P < 0.01) and plasma Cu concentrations quadratically decreased (P < 0.01) when ZnO concentrations were > 1,000 mg Zn/kg. Experiment 2 was conducted at seven stations (KY, MI, MO, NE, ND, OH, and OK) and evaluated the efficacy of an antibacterial agent (carbadox) in combination with added ZnO. The experiment was a 2 x 3 factorial arrangement in a randomized complete block design conducted in a total of 20 replicates. Carbadox was added at 0 or 55 mg/kg diet, and ZnO was added at 0, 1,500, or 3,000 mg Zn/ kg. A total of 918 pigs were weaned at an average 19.7 d of age. For the 28-d postweaning period, gains (P < 0.01), feed intakes (P < 0.05), and gain:feed ratios (P < 0.05) increased when dietary ZnO concentrations increased and when carbadox was added. These responses occurred in an additive manner. The results of these studies suggest that supplemental ZnO at 1,500 to 2,000 mg Zn/kg Zn improved postweaning pig performance, and its combination with an antibacterial agent resulted in additional performance improvements.  相似文献   

Cecal colonization of chicks by bovine-derived strains of Campylobacter     

Ziprin RL  Sheffield CL  Hume ME  Drinnon DL  Harvey RB 《Avian diseases》2003,47(4):1429-1433

Campylobacter jejuni and Campylobacter coli strains were isolated from feces of dairy cattle at farms with no known problem due to campylobacteria. Farms were located in the northeast, desert southwest, and Pacific west. Twenty isolates were identified by ribotyping with a RiboPrinter. The ability of these bovine isolates to colonize the ceca of chicks was determined by challenge inoculation and reisolation of the challenge strain from the ceca at 1 and 2 wk after challenge. Isolates recovered from chick ceca were examined by ribotyping to assure they matched the challenge strain. One hundred percent of the bovine-derived challenge strains were capable of colonizing chicks. These results indicate that dairy cattle may be asymptomatic Campylobacter carriers and potential sources of campylobacteria contamination of poultry facilities.  相似文献   

Effects of atropine, acepromazine, meperidine, and xylazine on gastroesophageal sphincter pressure in the dog   总被引：1，自引：0，他引：1  

D R Strombeck  D Harrold 《American journal of veterinary research》1985,46(4):963-965

Gastroesophageal sphincter (GES) pressure was 47.9 +/- 1.2 mm of Hg in nontreated dogs. Treatment with atropine, acepromazine, and xylazine reduced GES pressure to 13.2 +/- 2.03, 18.6 +/- 2.14, and 11.7 +/- 1.19 mm of Hg, respectively. Treatment with meperidine resulted in phasic contractions with minimum and maximum pressures of 27.9 +/- 4.55 and 98.9 +/- 9.16 mm of Hg, respectively. Drugs used in anesthetic procedures can reduce GES pressure in dogs.  相似文献   

Fertilizer Placement Tests With Potatoes     

T. E. Odland  S. C. Damon 《American Journal of Potato Research》1932,9(8):125-128

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Canola genotypes differ in potassium efficiency during vegetative growth   总被引：4，自引：0，他引：4  

P. M. Damon  L. D. Osborne  Z. Rengel 《Euphytica》2007,156(3):387-397

There is no knowledge about the differential capacity of canola genotypes to take up potassium (K) and produce dry matter under conditions of low soil K availability. Hence, 84 canola genotypes were screened for K efficiency in the glasshouse. Plants were grown in sealed pots containing K-responsive, sandy soil without or with K added. Twelve genotypes were selected for advanced screening in the glasshouse in a different K-responsive soil. Genotypes with a mean K efficiency ratio (the ratio of shoot dry weight at deficient and adequate K supply) greater than one standard error above or below the median genotype value were classified as K-efficient or K-inefficient, respectively. There were significant differences between genotypes in the K efficiency ratio in both screening experiments, indicating that genotypes responded differently to K availability. In the initial screening experiment, 19 genotypes were rated as K-efficient and nine genotypes rated as K-inefficient based on the K efficiency ratio. In the advanced screening experiment with 12 genotypes, three genotypes were rated as K-efficient and two as K-inefficient. Genotypes Wesbarker and Rainbow were K-efficient and Genkai K-inefficient in both experiments. Correlation of the K efficiency ratio with (i) shoot K content in the initial and advanced screening and (ii) shoot K concentration in the advanced screening, indicates that the observed differences in K efficiency were due to genotypic differences in both the uptake and the utilization of K. K-efficient genotypes have a potential to improve canola yields on soils with low K availability.  相似文献   

Genome streamlining in a cosmopolitan oceanic bacterium     

Giovannoni SJ  Tripp HJ  Givan S  Podar M  Vergin KL  Baptista D  Bibbs L  Eads J  Richardson TH  Noordewier M  Rappé MS  Short JM  Carrington JC  Mathur EJ 《Science (New York, N.Y.)》2005,309(5738):1242-1245

The SAR11 clade consists of very small, heterotrophic marine alpha-proteobacteria that are found throughout the oceans, where they account for about 25% of all microbial cells. Pelagibacter ubique, the first cultured member of this clade, has the smallest genome and encodes the smallest number of predicted open reading frames known for a free-living microorganism. In contrast to parasitic bacteria and archaea with small genomes, P. ubique has complete biosynthetic pathways for all 20 amino acids and all but a few cofactors. P. ubique has no pseudogenes, introns, transposons, extrachromosomal elements, or inteins; few paralogs; and the shortest intergenic spacers yet observed for any cell.  相似文献   

Bat diversity in montane rainforest and shaded coffee under different management regimes in southeastern Chiapas, Mexico     

Carlos García Estrada  Anne Damon  Lorena Soto Pinto 《Biological conservation》2006,132(3):351-361

Differences in alpha and beta bat diversity among montane rainforest and five shaded coffee plantations under different management regimes, as well as some environmental factors and vegetation parameters influencing bat richness, were evaluated for the first time in southeastern Chiapas, Mexico. In each site, bats were captured every 2 months from March 2004 to July 2005, with six mist-nets, during two nights, using the capture-recapture method. We captured 2970 individuals of 43 bat species. Montane rainforest had the greatest alpha diversity (H′ = 2.681; n = 37), whereas alpha diversity was similar among coffee plantations (H′ = 2.229-2.364; n = 23-26). The number of frugivorous and nectarivorous species was similar among the sites; the greatest exchange in species composition (beta diversity) occurred for insectivorous bats, which reduce their number in coffee plantations as pesticides are incorporated. Bat richness species was significantly related to the number of vegetation strata, height, and cover of trees. We suggest that coffee plantations could act as corridors, facilitating connection among different elements of the landscape in the Sierra Madre de Chiapas for some frugivorous and nectarivorous bats.  相似文献   

A seroepidemiologic survey of antibody to bluetongue virus in Alabama cattle     

T B Haynes  S Harrold  R D Schultz 《The Cornell veterinarian》1982,72(3):262-268

Bluetongue (BT) is an insect transmitted viral disease of sheep that often causes mild or inapparent disease but rarely causes severe disease in cattle. Until recently, bluetongue viral infection was believed to be more prevalent in the Western United States, as compared with other regions of the country. However, a national survey for bluetongue antibody and clinical evidence of the disease in the Southeastern United States prompted the present investigation that was designed to determine the serological prevalence of BT virus in Alabama cattle. Results of the study demonstrated that 16% of the samples collected from 1,500 cattle in 64 of the 67 counties were positive. The prevalence of positive cattle in the western part of the State was significantly higher (P less than .001) than the prevalence in the eastern half of the State. On a herd basis, 52% of all herds tested had positive animals. Results of this study suggest that bluetongue infection is more common in the Southeastern United States than previously suspected.  相似文献   

Potential involvement of mammalian and avian uncoupling proteins in the thermogenic effect of thyroid hormones   总被引：5，自引：0，他引：5  

Collin A  Cassy S  Buyse J  Decuypere E  Damon M 《Domestic animal endocrinology》2005,29(1):78-87

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