The situation is additionally worrying in view of the spreading pathogen Batrachochytrium salamandrivorans that originated from the region and has an impact on other amphibian species, particularly on Palearctic and Nearctic Caudata and anurans , with potentially catastrophic implications . Therefore, it is important to regulate movement of species that can spread pathogens through the pet trade, such as Laotriton laoensis , but also species such as the European Salamandra salamandrathat can carry pathogens to countries in East Asia . In addition, amphibians in Southeast Asia are also potentially threatened by emerging diseases from other parts of the globe. While the legal trade may be regulated, the illegal trade results in the movement of numerous individuals, such as dendrobatid frogs, through Lebanon and Kazakhstan, before being sold in Thailand , and these individuals are potential vectors of emerging diseases . The amphibian trade also results in the death of numerous individuals while they are shipped, an exacerbated problem in the case of the illegal trade. The current wildlife trade ban implemented by countries such as Vietnam resulted in some threatened species that were legally collected for the pet trade now being protected from harvesting, such as Theloderma palliatumAmphibian Specialist Group, 2017 and Theloderma bambusicolum , both under Governmental Decree No. 06/2019/NC-CP of Vietnam . From the point of view of a recipient country of the trade such as the R Korea, where more than 85 anuran and 37 caudate species are imported in the pet trade , 28 species such as Rana lessonae and Rana pipiens have been recently listed as “inflow-cautious organisms” and with efforts made to further limit the trade,hydroponic flood table now require special importation documentation . It is, however, necessary to acknowledge the benefit of amphibian farming locally for the pet trade in specific circumstances and under appropriate bio-security measures.
In addition, an acceleration of the CITES process regulating trade to better match, and catch-up with the IUCN assessments identifying trade as a risk for a particular species could help improve the situation . As an example, if species such as T. palliatum were included to CITES Appendix II , the trade of these species would halt, similarly to that of Hoplobatrachus tigrinus and Euphlyctis hexadactylus . Finally, investing in amphibian conservation in the wild in the form of habitat protection, and not their trade would be a valuable second step . Therefore, following in the path of other governments regulating pet trade to prevent the spread of zoonotic and panzootic diseases , we call for a stricter regulation in the amphibian pet trade. It would be beneficial that local and international trade accessibility be aligned with species extinction risk and specific trade threats highlighted by The IUCN Red list of Threatened Species, National Red Lists or other more recent and authoritative work. Additionally, quotas should be set and national regulations and CITES procedures should be enforced, along with the improvement of reporting and training of the national bodies responsible for enforcement. Species under the jurisdiction of the Department of Agriculture were excluded from the wildlife trade ban in China. This means that aquatic wildlife, with the exception of species explicitly banned by the Wildlife Protection Law or in protected areas, can be freely harvested and consumed . The reason for this is that the National People’s Congress qualifies aquatic species as a “natural resource and an important agricultural product, as well as a common international practice” . As a result, farmed amphibians on the List of National Key Protected Aquatic Wild Animals for Farming and the List of National Key Protected Economic Aquatic Animals and Plants Resources can be bred for consumption, or other consumables, and will remain so until further consideration from the Ministry of Agriculture and Rural Affairs from China .
Notable species omitted from the wildlife trade ban include newly described and recently discovered, but undescribed, species of Chinese giant salamanders and crocodile newts . While giant salamanders were formerly widely distributed across much of South and Central China, recent phylogenetic developments have split the clade into distinct species: A. davidianus, A. sligoi, and an undescribed species, known only from farms . Human-mediated translocations, trade, and release for commercial farming have also led to hybridisation and genetic homogenisation, blurring range delineations through population admixture. Wild Chinese giant salamander populations are now critically depleted or extirpated over much of their range , and extinction risk did not improve following the release of hundreds of thousands of farmed individuals into the wild . The genus Tylototriton contains morphologically similar species , several of which are listed as threatened on The IUCN Red list of Threatened Species and Chinese Red Lists . Some of these species are continually threatened by the intense harvesting pressure for the international pet trade and habitat destruction . Others, such as T. yangi, which is Endangered on The IUCN Red list of Threatened Species , are harvested to be dried, sold, and used for traditional medicine . The farming of Andrias spp. can be used to support ex-situ conservation breeding and has the potential to relieve harvest pressure on wild populations. However, while Andrias spp. have now been bred for several generations in commercial breeding farms, there are currently no existing Andrias spp. captive breeding programs that can produce offspring suitable for subsequent release into the wild. The often unknown provenance of founding stock, presence of multiple pathogens , and sometimes sub-optimal bio-security make current farming and breeding facilities inappropriate for conservation breeding. Furthermore, there is evidence that the exploitation of wild Andrias spp. is ongoing despite the existence of the farming industry . Improved supervision and monitoring by authorities is required to address this situation and it would be beneficial to set trade regulations with regard to genetic screening, provenance and pathogen surveillance in collaboration with scientific institutions.
There is a need for co-ordinated monitoring and protection of Andrias spp., as well as strengthening of legislation and enforcement to protect any surviving wild populations . Thus, termination of commercial farming in or near reserves because of the difficulty in regulating poaching, genetic testing for origin of clade before reintroduction, and the development of ecotourism to raise awareness has been recommended . While the original intention was likely to use ex situ breeding of Andrias spp. to alleviate poverty and protect wild populations through “sustainable” farming practices, farming and conservation are clearly different endeavours. Sustainable farming practices can support community development and relieve the pressure on wild populations; however, for the strengthening of in situ protection to safeguard wild Andrias spp., any conservation breeding and release would require strict monitoring. Similarly, several species of Tylototriton are now listed as Class II on the List of Endangered Species of China and law enforcement was reinforced during the breeding season of the species, with habitat restoration and captive breeding programs implemented, with support from local communities . It is important to ensure that the sustainable farming practices for these species do not result in an increased risk of zoonoses through pathogens such as Mycobacterium, a common bacteria in captive settings . Farms rearing Andrias spp. are currently permitted to release untreated effluent from indoor holding tanks directly into streams and rivers,hydroponic stands leading to a risk of pathogen transmission . Similarly, consumption of Tylototriton spp. as traditional medicine or in food markets can also result in cross-species pathogen transmission through human consumption as food or traditional medicine . A complete ban on amphibian farming is likely to be harmful to both the environment because of the resulting illegal and non-regulated harvests, and to the human communities who depend economically on the trade. A ban would also likely drive the market underground in addition to the unresolved question regarding either releasing or euthanising the millions of animals now in captivity. The wildlife farming industry is estimated to have employed more than 14 million people and to have generated over £56 billion in China, with food consumption involving species such as the Giant salamander, frogs, and peacocks representing 24% of the total profit . Therefore, we recommend a gradual shift away from non-sustainable farming practices to alleviate pressure on people affected by an edict , and with consideration given to the strengthening of wild amphibian populations, to ensure that unintended negative consequences to threatened species can be managed adequately. Carrageenan is a general name for polysaccharides extracted from certain species of red algae , mainly Gigartina stellata Batters, Chondrus crispus Stackhouse, Eucheuma spp., and Kappaphycus spp. Carrageenans are high molecular weight polysaccharides made up of repeating galactose units and 3,6-anhydrogalactose with varying numbers of sulfate groups connected by α-1,3 and β-1,4 glycosidic linkages. They are biocompatible compounds with specific gelling properties useful in a multitude of ways, including food and biotechnology programs and controlled drug release applications. Their reported anticancer, antioxidant, and antiviral activities have potential in the pharmaceutical industry, and the high metal binding capacities of carrageenans make them excellent candidates for nanoparticle synthesis and encapsulation processes . There are three primaryclassifications of carrageenan, and the genus Kappaphycus was segregated from Eucheuma primarily on the basis of carrageenan type . DNA re-association kinetics were used to determine nuclear genomic organization and complexity in the carrageenophyte Kappaphycus alvarezii Doty ex P.C. Silva .
Carrageenan occurs naturally in the cell walls and in the intercellular matrix of several red algae, and it has been studied using diverse methodologies and measures . Biochemical analysis and Fourier transformed infrared spectroscopy are the most commonly used tools for evaluation of carrageenan quality. Kappaphycus alvarezii has been actively farmed in many countries as a biomass source for carrageenan production since the early 1970s . However, the present-day carrageenan industry faces numerous challenges related to the quality and quantity of raw materials. As a result, in 2000, of the first-recorded occurrence of Polysiphonia sp. epiphytic filamentous algae , annual K. alvarezii production and the number of seaweed farmers declined rapidly . This raised serious concerns about the future stability of the algal resource that persists to the present time. The outbreaks of EFA caused by Polysiphonia sp. in the Philippines and the epiphyte Neosiphonia savatieri M.S. Kim & I.K. Lee in the Philippines and Malaysia caused a significant decrease in global K. alvarezii production. This decrease is reportedly correlated with drastic environmental changes in areas with low water motion in both of these locations. Morphological studies performed in China revealed that the main epiphyte on K. alvarezii was N. savatieri and reduced photosynthetic activity caused by extensive shading could be one of the primary reasons for the decreased productivity of K. alvarezii infected by N. savatieri . A sustainable seaweed farms project was established in the Caribbean Sea near the northern entrance of the Panamá Canal by Gracilarias de Panamá S. A. The objective was to cultivate species of red algae used by the communities of the Panamanian Caribbean areas and to provide an important livelihood activity for residents. The first seaweed farms were developed with the species Gracilaria domingensis Sonder ex Dickie and Eucheuma sp. . These two genera were reported to already inhabit this area . In 2006, in vitro culture methods were initiated at the Galeta Point Marine Laboratory of the Smithsonian Tropical Research Institute, which is located close to the areas where the seaweeds are cultivated . Panama is among the few countries in the Americas with commercial farming of Kappaphycus sp. that has exported production to Europe and Asia . Expertise obtained through the development and operation of the seaweed farms in the Caribbean of Panama revealed a need to improve and standardize various aspects of cultivation. In addition, it was hypothesized that improved selection processes for quality seedstock would result in a crop with higher carrageenan content. This study presents a procedure to identify and broaden knowledge of carrageenan content located in the cell wall and in the cell centers of the red alga K. alvarezii. Processes for enhancing carrageenan content were explored through in vitro techniques with treatment by three polyamines administered at different concentrations. Carrageenan was imaged in the treated explants at the Laboratory for Fluorescence Dynamics at the Department of Biomedical Engineering, University of California, Irvine, USA.