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241.
Michael I. Grant William T. White Yolarnie Amepou Leontine Baje Amy Diedrich Dotty Ibana Dick J. Jogo Stanley Jogo Peter M. Kyne Owen Li Ralph Mana Nigel Mapmani Anthony Nagul Darcy Roeger Colin A. Simpfendorfer Andrew Chin 《水产资源保护:海洋与淡水生态系统》2021,31(10):2883-2900
- Sawfish (Pristidae) are considered to be among the most threatened families of elasmobranch (sharks and rays). There is a need to gather information on the status of poorly known sawfish populations to assist in global recovery initiatives.
- This study used interviews with local fishers to investigate the presence of sawfish in southern Papua New Guinea (PNG) and their interactions with and uses and values for small-scale fishers.
- A range of sawfish size classes are still encountered throughout southern PNG, while juvenile largetooth sawfish Pristis pristis were additionally reported in the freshwater reaches of all rivers surveyed. Reports of large size classes in estuarine and marine environments provide an optimistic outlook that sawfish populations persist throughout southern PNG.
- Most fishers that catch sawfish retain them for various uses including consumption and for the sale of meat, fins and occasionally rostra. Negative population trends including decreases in catch frequency and/or size classes were reported by 66% of interviewees, with the largest declines being reported in the Kikori River. The increasing technical capacity of small-scale fishers, their preference for gillnetting and the emerging market for teleost swim bladder (a high-value fishery product) present a major ongoing threat to sawfish in southern PNG. Furthermore, the tendency of fishers to kill or remove rostra from entangled sawfish results in high fishing mortality regardless of any use by the fisher.
- This study indicates that considerable community engagement will be necessary to manifest any legislative actions or increased enforcement on international trade regulations for sawfish in PNG. This is due to traditional land and waterway ownership values throughout PNG and the local perception of sawfish as a traditional food resource rather than an animal of intrinsic biodiversity value as perceived by global conservationists. Future research should consider exploring culturally appropriate conservation initiatives that are likely to achieve engagement and participation from local fishers.
242.
For breeding programs of the tetraploid potato (Solanum tuberosum), both wild and cultivated diploid relatives are valuable sources of genetic diversity. While both types of germplasm are
used in breeding programs, there are several advantages to using wild relatives. Diploid relatives are typically crossed with
haploids (2n = 2x = 24) from tetraploid S. tuberosum to improve daylength adaptation. Most haploids are male sterile, so they are typically used as female parents. Cultivated
diploids, such as members of the Phureja Group, produce male sterile hybrids when crossed as females to haploids; wild relatives,
such as S. tarijense, often produce male fertile hybrids. Tuber yield following crosses of haploids to cultivated or wild relatives is often high.
However, cultivated relatives generally produce hybrids with a high set of small tubers; hybrids from wild relatives are variable,
but many are similar to cultivars in tuber size and set. While tubers of hybrids from cultivated relatives are typically rough,
with deep eyes and raised internodes, those from wild relatives are often smooth. Tuber dormancy in hybrids with cultivated
relatives is generally short, while that in hybrids with wild species is longer, allowing for storage over winter. Finally,
resistance to several major diseases and stresses has been found in wild species and their hybrids with S. tuberosum haploids. The desirable traits in hybrids are transmitted to tetraploids via unilateral sexual polyploidization (4x × 2x
or 2x × 4x crosses in which the diploid parent produces 2n gametes). Wild Solanum species are recommended for use in potato breeding programs as sources of genetic diversity that can be adapted easily following
hybridization with S. tuberosum haploids. 相似文献
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Kaewmongkol G Kaewmongkol S Burmej H Bennett MD Fleming PA Adams PJ Wayne AF Ryan U Irwin PJ Fenwick SG 《Comparative immunology, microbiology and infectious diseases》2011,34(5):411-417
A variety of Bartonella species were detected in two species of ticks and three species of fleas collected from marsupial hosts; brush-tailed bettong or woylie (Bettongia penicillata) and western barred bandicoots (Perameles bougainville) and from a rodent host; Rattus fuscipes in Western Australia. Bartonella species were detected using nested-PCR of the gltA gene and the 16S–23S ribosomal internal transcribed spacer region (ITS), and species were characterized using DNA sequencing of the 16S rRNA, gltA, rpoB, ftsZ genes and the ITS region. Bartonella rattaustraliani and B. coopersplainsensis were detected in Ixodes spp. ticks and fleas (Stephanocircus pectinipes) respectively collected from rodents. Two novel Bartonella species were detected from marsupials; Candidatus Bartonella woyliei n. sp. was detected in both fleas (Pygiopsylla hilli) and ticks (Ixodes australiensis) collected from woylies and Candidatus Bartonella bandicootii n. sp. was detected in fleas (Pygiopsylla tunneyi) collected from western barred bandicoots. Concatenated phylogenetic analysis of all 5 loci clarified the marsupial cluster of Bartonella species in Australia and confirmed the species status of these two Bartonella species in ticks and fleas from woylies and western barred bandicoots, which are classified as threatened species and are vulnerable to extinction. 相似文献
246.
Dimaio Knych HK Steffey EP Deuel JL Shepard RA Stanley SD 《Journal of veterinary pharmacology and therapeutics》2011,34(1):58-63
DiMaio Knych, H.K., Steffey, E.P., Deuel, J.L., Shepard, R.A., Stanley, S.D. Pharmacokinetics of yohimbine following intravenous administration to horses. J. vet. Pharmacol. Therap. 34 , 58–63. Yohimbine is an alpha 2 adrenergic receptor antagonist used most commonly in veterinary medicine to reverse the effects of the alpha 2 receptor agonists, xylazine and detomidine. Most notably, yohimbine has been shown to counteract the CNS depressant effects of alpha 2 receptor agonists in a number of species. The recent identification of a yohimbine positive urine sample collected from a horse racing in California has led to the investigation of the pharmacokinetics of this compound. Eight healthy adult horses received a single intravenous dose of 0.12 mg/kg yohimbine. Blood samples were collected at time 0 (prior to drug administration) and at various times up to 72 h post drug administration. Plasma samples were analyzed using liquid chromatography–mass spectrometry (LC‐MS) and data analyzed using both noncompartmental and compartmental analysis. Peak plasma concentration was 114.5 + 31.8 ng/mL and occurred at 0.09 + 0.03 h. Mean ± SD systemic clearance (Cls) and steady‐state volume of distribution (Vdss) were 13.5 + 2.1 mL/min/kg and 3.3 + 1.3 L/kg following noncompartmental analysis. For compartmental analysis, plasma yohimbine vs. time data were best fitted to a two compartment model. Mean ± SD Cls and Vdss of yohimbine were 13.6 ± 2.0 mL/min/kg and 3.2 ± 1.1 L/kg, respectively. Mean ± SD terminal elimination half‐life was 4.4 ± 0.9 h following noncompartmental analysis. Immediately following administration, two horses showed signs of sedation, while the other six appeared behaviorally unaffected. Gastrointestinal sounds were moderately increased compared to baseline while fecal consistency appeared normal. 相似文献
247.
Joseph Wakshlag DVM PhD DACVN DACVSMR Gretchen L. Schoeffler DVM DACVECC Duncan S. Russell DVM DACVP Rachael S. Peters‐Mo DVM DACVP Olivier Toulza DVM DACVIM 《Journal of Veterinary Emergency and Critical Care》2011,21(4):375-381
Objective – To describe the pathologic consequences of parenteral nutrition (PN) extravasation into the mediastinum of a cat. Case Summary – An 8‐year‐old domestic short hair cat with persistent vomiting and anorexia was initiated on PN for nutritional support. PN was being administered at a rate of 12.9 mL/h when inadvertent jugular catheter migration resulted in thrombophlebitis and cellulitis and 40–80 mL of PN extravasated into the SC and mediastinal tissues. The cat was euthanized 36 hours after the extravasation of PN due to poor prognosis related to the gastric complications associated with a presumed primary gastrinoma. Grossly there was excessive mediastinal lymphatic drainage and pronounced edema in the cervical SC and mediastinal tissue. Histopathologic examination of the PN‐extravasated area revealed a severe mixed inflammatory reaction, represented by a severe neutrophilic and mild histiocytic infiltrate with lymphoplasmacytic perivascular cuffing. No bacterial agents were observed or cultured from this area. Unique Information Provided – This is the first case report of a foreign body‐type reaction due to extravasation of PN (extravasation injury) in a cat. Extravasation of PN is not without pathologic consequence, and can result in a severe inflammatory reaction in affected tissues. 相似文献
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