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1.
Conserv Biol ; 2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35098582

RESUMO

An important rationale for legally-farmed and synthetic wildlife products are that they reduce illegal wild-sourced trade by supplying markets with sustainable alternatives. For this to work, more established illegal-product consumers must switch to legal alternatives than new legal-product consumers drawn to illegal wild products. Despite widespread debate on the magnitude and direction of switching, studies among actual consumers are lacking. We used an anonymous online survey of 1421 Traditional Chinese Medicine consumers in China to investigate switching between legal farmed, synthetic, and illegal wild bear bile. We examined past consumption behaviour, and applied a discrete choice experiment framed within worsening hypothetical disease scenarios, using latent class models to investigate groups with shared preferences. Bear bile consumers (86% respondents) were wealthier, more likely to have family who consumed bile, and less knowledgeable about bile treatments than non-consumers. Consumer preferences were heterogenous but most consumers preferred switching between bile types as disease worsened. We identified five distinct latent classes within our sample: 'law-abiding consumers' (34% respondents), who prefer legal products and were unlikely to switch; two 'all-natural consumer' groups (53%), who dislike synthetics but may switch between farmed and wild products; and two 'non-consumer' groups (12%) who prefer not to buy bile. People with past experience of bile consumption had different preferences than those without. Willingness to switch to wild products was related to believing they were legal, although the likelihood of switching was mediated by preferences for cheaper products sold in legal, familiar places. We show that consumers of wild bile may switch, given the availability of a range of legal alternatives, while legal-product consumers may switch to illegal products if the barriers to doing so are small. Understanding preferences that promote or impede switching should be a key consideration when attempting to predict consumer behaviour in complex wildlife markets. This article is protected by copyright. All rights reserved.


Wildlife consumer characteristics and preferences determine their likelihood and direction of switching between legal and illegal products.

2.
Anim Reprod Sci ; 53(1-4): 107-18, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9835370

RESUMO

Identifying steroid and pituitary hormone profiles in the female black bear (Ursus americanus) throughout pregnancy may provide a greater understanding of the reproductive cycle and indicate which hormones are required for implantation. Our objective was to assess endocrine activity in black bears oestrus onset, at oestrus, during pregnancy and after parturition. Serum samples were obtained from 12 captive, 16 uncollared and five radiocollared free-ranging female black bears from March through the end of December and assayed for serum progesterone, oestradiol, luteinizing hormone (LH) and prolactin (PRL). In captive bears, progesterone concentrations were low at days 0-10 after oestrus and increased significantly days 25-35 and 45-52 after oestrus. Oestradiol concentrations were high at oestrus (day 0) and days 4-10 after oestrus and then decreased days 25-35 and 45-52 after oestrus. LH concentrations were not significantly different throughout the sampling period. Changes in PRL concentrations pattern were similar to those of oestradiol, with elevated levels at oestrus and days 4-10 after oestrus, followed by a significant decrease 45-52 days after oestrus. In non-collared free-ranging bears, progesterone concentrations increased gradually after mating with a further significant increase in November-December. Oestradiol concentrations were highest in March (before mating) and in June (during mating) followed by a significant decrease in July (early delay period) and November-December (peri-implantation period). LH concentrations were low until November-December and then increased significantly. PRL concentrations were low in March (before mating), increased significantly during the mating season in June, decreased slightly in July, and were low in November-December (peri-implantation period). In radiocollared free-ranging bears, serum progesterone concentrations were elevated in pregnant bears in December and extremely low in lactating and non-lactating bears in March. Oestradiol levels were slightly higher in pregnant bears in December than in non-lactating or lactating bears in March. PRL concentrations were considerably higher in lactating bears in March than in pregnant bears in December. Our results suggest that: (1) serum progesterone concentrations are low, but detectable during the early delay implantation period and greatly elevated during the peri-implantation period; (2) serum oestradiol concentrations are elevated at oestrus and decline during the delay period; (3) LH may be involved in luteal activation; and (4) the decline of serum PRL concentrations during short days may be necessary for implantation to occur.


Assuntos
Estradiol/sangue , Hormônio Luteinizante/sangue , Progesterona/sangue , Prolactina/sangue , Ursidae/sangue , Animais , Estro/fisiologia , Feminino , Gravidez , Valores de Referência , Reprodução/fisiologia , Estações do Ano
3.
J Vet Med Sci ; 61(1): 81-3, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10027172

RESUMO

Serum sex steroid and prolactin profiles were examined in the male American black bear, Ursus americanus during denning. Sera collected in December and the following March from 8 denning male black bears in Minnesota, U.S.A. were assayed for testosterone, estradiol-17 beta and prolactin. Eight bears were confirmed to be the denning mode based on a serum urea to creatinine ratio less than 10. Serum testosterone concentrations tended to increase from December to the subsequent March whereas serum estradiol-17 beta concentrations tended to decrease during this period. There were few changes in serum prolactin concentrations between December and March. These findings suggest that spermatogenesis and testicular steroidogenesis initiated during denning may be influenced by changes in serum sex steroid concentrations in the American black bear.


Assuntos
Hormônios Esteroides Gonadais/sangue , Hibernação , Prolactina/sangue , Ursidae/sangue , Animais , Estradiol/sangue , Masculino , Valores de Referência , Estações do Ano , Testosterona/sangue
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