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91.
This is a study of vertebral deformities in ornamental koi based on computed radiography and skeletons cleaned by dermestid beetles (Dermestes maculatus). All koi developed gradual onset of swimming abnormalities as adults. Extensive intervertebral osteophyte formation correlated with age of fish and was associated with hindquarter paresis in one koi. Vertebral compression and fusion were the most common spinal deformities occurring at multiple sites, similar to findings in other farmed fish. Site‐specific spinal deformities were thought to develop due to differences in swimming behaviour and rates of vertebral growth. One koi had offspring with spinal deformities. Spinal deformities are significant problems in both European and Australian food fish hatcheries. The heritability of vertebral deformities in farmed fish is reportedly low unless there is concurrent poor husbandry or nutritional deficiencies. The specific aetiologies for vertebral deformities in koi in this study could not be ascertained. Current knowledge on spinal deformities in the better studied European food fish species suggests multifactorial aetiologies. Future research should include prospective longitudinal studies of larger numbers of koi from hatch and consideration of all potential risk factors such as husbandry, nutrition, temperature, photoperiod and genetics.  相似文献   
92.
Journal of Plant Diseases and Protection - Loquat (Eriobotrya japonica) has potential to be produced in the central part of Mexico. During summer 2017, anthracnose symptoms were observed in Tetela,...  相似文献   
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The Acacia mangium tree contains 10% bark (v/v), of which about 20% are extractives. Extraction of this bark using a combination of water and sulfite medium can produce between 15% and 25% tannin materials (dry weight). In this work, several extraction conditions such as bark size, plantation site, extraction time and extraction medium were studied. The results showed that by using either hot water or a sulfite medium, a reasonable amount of tannin yield can be obtained. Bark size of less than 1-mm mesh size gave relatively high tannin yield irrespectively of the extraction medium used. Using a 600:100:2:0.5 (w/w) ratio of water:bark:sodium sulfite:sodium carbonate, and reacted at 75 °C for 3 h improved the tannin yield by at least 30%. The extracts were reasonably reactive towards formaldehyde as shown by their high Stiasny number; water extract, 60–70% and aqueous sulfite–carbonate extracts, 85–90%. The gluing results showed that the shear strength of the plywood can meet the requirements of the European Standards EN 314-1 and EN 314-2:1993. Incorporation of low molecular weight PF resin (10 parts) and PF (10 parts) improved the shear strength from 0.96 MPa to 1.43 MPa after a 72 h boiling test. This study showed that A. mangium tannin blended with commercial plywood phenol–formaldehyde resin, low molecular weight PF and paraformaldehyde as a cross-linker can be used to bond Kedondong (Canarium spp.) wood veneers suitable for both interior and exterior grade plywood.  相似文献   
96.
The present study assessed the effect of feeding palm oil (PO), sunflower oil (SO) and their combination on performance, fat deposition, fatty acid composition and lipogenic gene expression of broilers reared for 42 days. A total of 144 1‐day‐old broilers (Cobb500) were randomly allotted into four treatment diets with each having six replicates of six chicks in each replicate following a completely randomized design. Live weight gain and feed efficiency was significantly (P < 0.05) higher in birds fed with a combination of oil sources compared to controls. Birds fed with the combination of oil and SO alone had higher carcass yield and lower abdominal fat. Higher (P < 0.05) concentrations of unsaturated fatty acids (UFA) and lower concentrations of palmitic acid and saturated fatty acid (SFA) was found in birds fed SO alone and combinations of SO and PO. Furthermore, the outcomes showed that birds fed diet supplemented with SO and the combination of SO and PO down‐regulated gene expression of key hepatic lipogenic enzymes of fatty acids synthase (FAS), acetyl‐CoA carboxylase (ACC) and stearoyl‐CoA desaturase (SCD). These findings suggest that the diet containing the combination of 2% PO and 4% SO may reduce hepatic lipogenesis, as well as lower abdominal fat content of broilers.  相似文献   
97.
Fuelwood is the main source of energy for various household uses in many developing countries; and management of tree resources where it is obtained can be best undertaken when household choice patterns are understood. In this paper, households’ decision to obtain fuelwood for domestic consumption as influenced by household and fuelwood source characteristics is analyzed using a multinomial probit regression model. Data is obtained from 254 randomly selected household drawn from Mbarali district, south-western Tanzania. Results indicate that households are heavily dependent on natural forests for household energy provision and that the choice to obtain fuelwood from the forest, farm or market depends, among other factors on the availability of preferred fuelwood tree species at these sources. Acacia tortilis, Brachystegia spp. and Faidherbia albida are the significantly preferred tree species and hence affect the decision of where to obtain fuelwood. This revelation highlights the pressure applied to surrounding forests as well as to the aforementioned tree species which require immediate management interventions. The gender of the household head and whether the household lives in peri-urban or rural areas also influence choice of fuelwood source. Promotion of tree planting and on-farm management of tree species similar to preferred species found in natural forests is recommended. To the extent that consumer preferences are likely to change over time, further research using panel datasets is necessary to unravel inter-temporal preferences for fuelwood sources.  相似文献   
98.
The generation of protective immunity against Riemerella anatipestifer infection in ducks were investigated by immunizations with recombinant glutathione sulfatransferase (GST) fusion's proteins of OmpA, a 42kDa major outer membrane protein, and P45N', a 41kDa N-terminal fragment of a newly identified 45kDa potential surface protein from R. anatipestifer. The DNA encoding OmpA and P45N' were isolated from R. anatipestifer serotype 15 (field strain 110/89) and serotype 19 (reference strain 30/90), respectively. Immunoblotting and ELISA results showed that the purified recombinant proteins induced the production of antibodies in immunized ducks. However, neither was protective against subsequent challenge with the virulent serotype 15 strain, 34/90. All the five ducks immunized with formalinized R. anatipestifer strain 34/90 survived the challenge with the homologous strain whereas six out of seven ducks in the non-immunized control group died within a week following the challenge.  相似文献   
99.
Fifteen independently isolated complementary DNA clones that contain T-cell receptor (TCR) V beta genes were sequenced and found to represent 11 different V beta genes. When compared with known sequences, 14 different V beta genes could be defined from a total of 25 complementary DNA's; 11 clones therefore involved repeated usage of previously identified V beta's. Based on these data, we calculate a maximum likelihood estimate of the number of expressed germline V beta genes to be 18 with an upper 95 percent confidence bound of 30 genes. Southern blot analysis has shown that most of these genes belong to single element subfamilies which show very limited interstrain polymorphism. The TCR beta-chain diversity appears to be generated from a limited V beta gene pool primarily by extensive variability at the variable-diversity-joining (V-D-J) junctional site, with no evidence for the involvement of somatic hypermutation.  相似文献   
100.
Sarcoplasmic proteins of four colour varieties of Siamese fighting fish, Betta splendens Regan, were analysed by isoelectric focusing (IEF). Genetic polymorphisms were detected in six loci having isoelectric points: 4.92-5.00 (Sp-1), 5.33-5.48 (Sp-2), 5.90 (Sp-3), 6.31-6.35 (Sp-4), 6.58-6.70 (Sp-5) and 6.90 (Sp-6). For the Sp-1, Sp-2, Sp-4 and Sp-5 loci, there were two co-dominant alleles. At Sp-3 and Sp-6, one allele was dominant and the other null. Individuals within each locus were classified into phenotypes A, AB and B. Only homozygotes were found at Sp-2. Allele frequencies were calculated for each locus and tested for accordance with the Hardy-Weinberg equilibrium. Observed values for each phenotype at Sp-1, Sp-3, Sp-4, Sp-5 and Sp-6 agreed well with the expected ones. At Sp-2, genotypic frequencies for each variety deviated markedly (p < 0.01) from the equilibrium. When tested for homogeneity, no significant differences (p 0.95) in gene frequencies were found among the varieties except at Sp-2. Band sharing index (BSI), computed using the BIO-GENE v5.04 program, revealed high intravariety genetic similarities (0.701-0.740) and slightly above-average intervariety values (0.550-0.583). In this study, we estimated the levels of genetic variability in B. splendens, and proposed a genetic model for each polymorphic locus.  相似文献   
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