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81.
Emerging diseases are acknowledged as a growing threat to wildlife, with the continued identification of pathogenic and potentially pathogenic viruses in avian species resulting from ongoing advances in molecular diagnostic techniques. Parvoviruses under the genus Chaphamaparvovirus (subfamily Hamaparvovirinae) are highly divergent. The detection and characterisation of parvoviruses in psittacine birds is limited. This study reports a novel parvovirus, tentatively named psittaciform chaphamaparvovirus 3 (PsChV-3) under the genus Chaphamaparvovirus, identified in an Australian free-ranging little corella (Cacatua sanguinea). The PsChV-3 genome is 4277 bp in length and encompasses four predicted open-reading frames, including two major genes, a nonstructural replicase gene (NS1), and a structural capsid gene (VP1). The NS1 and VP1 genes showed the closest amino acid identities of 78.8% and 69.7%, respectively, with a recently sequenced psittaciform chaphamaparvovirus 2 from Australian Neophema species grass parrots. In addition, the presence of two complete novel beak and feather disease (BFDV) genomes, 1993 and 1868 nt in length, respectively, were detected from the same bird. Both these BFDV genomes contained two bidirectional ORFs encoding the putative Rep and Cap proteins. Phylogenetic analysis showed that the sequenced novel BFDV genomes clustered in a distinct subclade with other BFDVs isolated from Australian cockatoos. This study contributes to the characterisation chaphamaparvoviruses and BFDV in Australian parrots and supports the need for ongoing monitoring and molecular studies into the avian virome in native Australian psittacine bird species.  相似文献   
82.
The current study was conducted to investigate the protective efficiency of dietary lycopene (LYC) supplementation on growth performance, intestinal morphology, and digestive enzyme activities aflatoxinB1 (AFB1) challenged broilers. A total of 240 days old Arber across male broiler chicks were randomly allocated in five treatments and six replicates (eight birds per replicate); feed and water were provided ad libitum during the 42 days experiment. The treatment diets were as follows: (i) Basal diet (control), (ii) Basal diet + 100 µg/kg AFB1 contaminated diet, (iii) Basal diet + 100 µg/kg AFB1 + 100 mg/kg LYC1, (iv) Basal diet + 100 µg/kg AFB1 + 200 mg/kg LYC2, and (v) Basal diet + 100 µg/kg AFB1 + 400 mg/kg LYC3. The results showed that the addition of LYC to AFB1 contaminated broiler diets significantly increased (p < .05) average daily gain (ADG) and decreased feed conversion ratio (FCR) compared to the AFB1 diet. AFB1 diet decreased the intestinal villus height (VH) and crypt depth ratio (VCR) while increasing the crypt depth (CD). However, dietary LYC supplemented diets relieved the intestinal morphological alterations. Dietary LYC supplementation (200 and 400 mg/kg) significantly improved (p < .05) intestinal digestive enzyme amylase and lipase activities with AFB1 contaminated diet. These findings suggested that LYC is a promising feed supplement in the broiler industry, alleviating the harmful effects of AFB1.  相似文献   
83.
ABSTRACT:   The benthic nutrient fluxes in Suo Nada, in the western part of Seto Inland Sea, Japan were estimated seasonally in 2002, and their contribution to the pelagic nutrient cycle was evaluated. The horizontal distributions of inorganic phosphorus (DIP), ammonia and dissolved silica (DSi) concentrations in the pore water of the surface (0–3 cm) sediments were high in the western part, indicating a eutrophic condition relative to the other parts. Seasonally, the highest nutrient concentration in the pore water was observed in summer, as reflected by the increasing decomposition rate of organic matter. Multiple regression analyses revealed significant positive effects of acid volatile sulfide (AVS) and temperature on the DIP flux and also significant positive effects of ignition loss (IL) along with these two parameters on the dissolved inorganic nitrogen (DIN) flux. Temperature, IL and redox potential (Eh) were effective on DSi. The estimated DIP, DIN and DSi fluxes from the sediments were relatively high or equivalent to the total inputs from rains and rivers in annual average, with high values in summer of 2–3-fold higher than the other sources (rain plus rivers). Thus, it is concluded that the benthic nutrient fluxes play an important role in the pelagic nutrient cycle of the Suo Nada ecosystem.  相似文献   
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