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941.
  1. Most of the Bornean endemic freshwater mussel (Unionida) species known to date have not been recorded by science for the past 50 years or more, owing to a lack of research effort and presumed population losses.
  2. This study assessed current patterns and recent changes in the diversity and distribution of freshwater mussels in north-eastern Borneo. Physical surveys and interviews were conducted at 24 sites, and anecdotal evidence for current or historical presence of mussels was collected for a further 13 sites.
  3. Native species, i.e. Schepmania sp. and Khairuloconcha sahanae gen. & sp. nov., were only found in one small stream of the Kinabatangan River basin within the Gomantong Forest Reserve, whereas the non-native Sinanodonta cf. woodiana was common across the study area.
  4. Molecular phylogenetics (five genes) of the native taxa, including comparative material from West Kalimantan and Sarawak, revealed: (i) the presence of a new genus with two new, rare species: Khairuloconcha lunbawangorum sp. nov. in the Limbang River basin and K. sahanae in the Kinabatangan River basin; (ii) that Khairuloconcha and Ctenodesma form the Bornean endemic tribe Ctenodesmini trib. nov.; and (iii) that Schepmania represents another Bornean endemic tribe Schepmaniini trib. nov.
  5. Both Khairuloconcha gen. nov. species are known from a single stream each and are apparently restricted to forest stream habitats where they occur at very low densities. Schepmania appears to have a severely contracted range in the Kinabatangan and adjacent basins. We urgently call for full protection of the currently known sites of K. lunbawangorum and K. sahanae, and development of an action plan to save the Bornean freshwater mussel fauna.
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942.
ABSTRACT

In this study, the cryopreserved spermatozoa of Epinephelus lanceolatus were transported using a novel method involving dry ice as the medium of preservation and a Styrofoam box. Five conditions were investigated for the cryopreserved sperm under different dry ice exposure times of (24, 48, and 72) h corresponding to treatment 1 (T1), 3 (T3), and 5 (T5), respectively. Meanwhile, the remaining treatments (T2 and T4) involved the same exposure to dry ice for (24 and 48) h followed by re-immersion into liquid nitrogen (LN). The performance of the cryopreserved spermatozoa of the hybrid grouper (E. fuscoguttatus ♀ × E. lanceolatus ♂) was evaluated through fertilization and hatching trials. The results showed no significant difference in fertilization for all five treatments. However, significantly poorer hatching rates than the fresh sperm were observed for spermatozoa exposed to dry ice after 48 h. This study recommends the use of the proposed method to successfully transport E. lanceolatus spermatozoa for the production of hybrid groupers via artificial insemination.  相似文献   
943.
1. The present study was conducted to develop Citrus junos probiotics (CJP), using by-products of Citrus junos fermented with multispecies probiotic bacteria including Saccharomyces cerevisiae, Enterococcus faecium, Lactobacillus acidophilus and Bacillus subtilis. The effects of dietary CJP on the growth performance, immune status, caecal microbiology and meat oxidative stability of broiler were investigated.

2. A total of 240 one-day-old Ross broiler chicks were used in a 35-d experiment in which the chicks were randomly allotted to one of the 4 dietary treatments (0, 5, 10 and 20 g CJP/kg diet) in a completely randomised design.

3. Dietary supplementation of 5 g/kg CJP significantly increased body weight, average daily gain and average daily feed intake of broiler during the overall experimental period.

4. Serum immunoglobulin (Ig)M concentration was significantly increased by 10 and 20 g/kg CJP, whereas the IgG and IgA concentration remained unaffected. In addition, 20 g/kg CJP significantly inhibited proliferation of Escherichia coli without affecting the concentration of Lactobacillus or Bacillus spp.

5. A significant reduction in the thiobarbituric acid reactive substances values of breast and thigh meat was observed in response to increasing concentration of dietary CJP.

6. Thus, the results suggest that CJP up to a concentration of 20 g/kg can be used in the diet of broilers to improve immunity and to reduce caecal E. coli and TBARS values of breast and thigh meat without any adverse effects on growth performance.  相似文献   

944.
1. Corni fructus is the fruit of Cornus officinalis, a dogwood species. This study was conducted to prepare fermented corni fructus preparation (FCFP) and fermented kelp (FK) from corni fructus and by-products of Laminaria japonica fermented with Bacillus subtilis and Aspergillus oryzae.

2. The effects of dietary FCFP and FK as replacer of oxytetracycline (OTC) on growth performance, meat composition, meat oxidative stability, and emissions of ammonia (NH3) and hydrogen sulphide (H2S) from broiler chicken droppings were investigated.

3. A total of 140 d-old broiler chicks were randomly allotted to 4 dietary treatments including control, OTC (0.05 g/kg), FCFP (5 g/kg), and FK (5 g/kg).

4. Overall, inclusion of FCFP resulted in lower weight gain and feed intake during the overall experimental period. Broilers fed FCFP diets tended to have lower crude fat and higher crude ash content in the carcasses.

5. In the fresh state, the malondialdehyde (MDA) value of broiler meat was lower in the FK supplemented group. At one week, meat from broilers fed antibiotic and FK diets had lower MDA values, whereas at 2 weeks broiler meat from all dietary treatment groups had lower MDA values than the control.

6. Dietary supplementation with FK significantly reduced faecal NH3 emissions throughout the experimental period, whereas dietary OTC and FCFP supplementation increased NH3 emissions at 2 and 4 weeks. There were no significant effects of dietary treatments on H2S emissions throughout the experimental period, except during week one, when FCFP supplementation reduced the emission.

7. In conclusion, dietary supplementation with 5 g/kg FK improved the oxidative stability of broiler meat and reduce faecal NH3 emissions without affecting growth performance.  相似文献   

945.
Rainbow trout were exposed to 200 g cadmium/l in the water during four months at 6–10°C. The liver, kidney and gills were analyzed for cadmium, copper, zinc, metallothionein and metallothionein mRNA. Cadmium accumulated in all three organs and reached the highest concentration in the kidney. The tissue zine and copper concentrations showed no major alterations during the experiment. The cytosolic distribution of cadmium, copper and zinc was followed during four months of exposure by Sephadex G-75 chromatography. It was found that cadmium was predominantly associated with proteins of an apparent molecular vieght of 10,000 daltons. These proteins were further identified as metallothioneins after fast protein liquid chromatography on a Mono-Q column. The metallothionein concentration was significantly higher in liver of exposed fish than in control fish after only one month. The kidneys reached significantly elevated levels of metallothionein in the exposed group after three months. In the gills, elevated metallothionein concentrations were observed after four months of exposure. After four months of exposure, the metallothionein mRNA content of liver and kidney was analyzed using a rainbow trout anti-sense RNA probe. Elevated MT mRNA levels were observed in both kidney and liver. These results demonstrate thatde novo synthesis of metallothionein is induced by cadmium in rainbow trout after exposure to the metalvia water.  相似文献   
946.
In this study, the response of Eucalyptus camaldulensis and Acacia mangium kraft pulp to different options of ECF bleaching was investigated. Oxygen-delignified pulps of both species having similar kappa number (c.a. 12) were used. Both the pulps were prebleached using conventional ClO2 stage (D0), combined use of ClO2 and O3 (DZ), hot acid treatment before D0 (AhotD0) and hot acid treatment before (DZ) i.e., Ahot(DZ), hot ClO2 treatment (DHT) and Ahot followed by DHT (AhotDHT). All prebleached pulps were finally bleached to 90%+ ISO brightness using D1 option. The overall benefits of other options were not considerable compared to D0 and (DZ). From the ClO2 consumption point of view, for a certain species, the option Ahot(DZ) was the best. Instead of D1 in final bleaching, pressurized hydrogen peroxide (PO) was also investigated in the case of D0 and (DZ) prebleached pulps. (PO)-bleached pulp produced higher brightness stability but lower viscosity compared to D1.  相似文献   
947.
Two new bergenin derivatives, named rivebergenin A and B (1, and 2), together with two known compounds, bergenin (3) and norbergenin (4) were isolated from the stem of Rivea hypocrateriformis (Desr.) Choisy. The structures of the new compound have been assigned from 1H and 13C NMR spectra, DEPT, and by 2D COSY, HMQC, and HMBC experiments. Compounds 1-4 showed the strong antioxidant activity.  相似文献   
948.
Tropical Animal Health and Production - The objective of this study was to determine the effect of supplementations of Leucaena leucocephala or Gliricidia sepium by goats fed old Panicum maximum...  相似文献   
949.

The objective of this study was to determine the effect of increasing total nutrient supply by increasing level of concentrate supplementation in forage-based diet of growing Nili-Ravi buffalo replacement heifers on pre-pubertal growth rate and its impact on age at puberty and post-pubertal productive and reproductive performance. Twenty-eight Nili-Ravi buffalo heifers of 7 ± 1 month age were divided into 3 groups. The treatments were 3 levels of concentrate (crude protein (CP) = 17.9%, metabolisable energy (ME) = 2.66 Mcal/kg), i.e. 0.5, 1, and 1.5% of the body weight referred as low, medium, and high treatments, respectively. Irrespective of pre-pubertal treatment, all the heifers received similar feed after puberty up to completion of their first lactation. The results of the study showed a similar response across the treatments in age, weight, and condition at puberty, weight at calving, lactation length, and yield. The medium and high treatments resulted in poor reproductive performance because of higher services per conception and less number of heifers confirmed conceived compared with low treatment. The low treatment resulted in less mortality compared with medium and high treatments. The feeding cost per animal at puberty, conception, and calving was lowest for treatment low as compared with medium and high. In conclusion, the results of the study showed that Nili-Ravi buffalo heifers achieved puberty at 23 months with feeding of concentrate (CP = 17.9%, ME = 2.66 Mcal/kg) during pre-pubertal stage at the rate of 0.5% of the body weight with better reproductive performance.

  相似文献   
950.
Tropical Animal Health and Production - Spirulina has been used as a food source from many years for human and animals because of its superior profile of nutrition. Spirulina (SPA) having antiviral...  相似文献   
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