Abstract: Melengestrol acetate (MGA) is the most widely used contraceptive in zoo felids, but the mechanism of contraception and the pathologic effects have not been investigated. For this study, the effects of MGA on folliculogenesis were assessed, and the association of MGA with ovarian lesions was evaluated. Comparisons were made among the histopathologic findings in the ovaries from 88 captive wild felids (representing 15 species) divided into three groups: 37 currently contracepted with MGA, eight previously exposed to MGA, and 43 never contracepted. Ninety-one percent of the felids evaluated had tertiary follicles, and no differences were noted between contracepted and uncontracepted cats. Some MGA-contracepted cats also had corpora lutea indicating recent ovulation. These results indicate that folliculogenesis is not suppressed by current doses of MGA and ovulation occurred in some cats. Therefore, the contraceptive actions of MGA do not occur by suppressing folliculogenesis, and MGA-contracepted felids likely have endogenous estrogens that may confound progestin effects on the uterus. Cystic rete ovarii was the most common pathologic finding, but they were not more prevalent in MGA-contracepted cats. These findings indicate that MGA is not associated with ovarian disease, including ovarian cancer, in contrast to the uterine lesions noted in MGA-treated cats.

Abstract: Nine small cats, including one bobcat (Felis rufus), one Pallas cat (F. manul), one Canada lynx (F. lynx canadensis), two fishing cats (F. viverrina), two margays (F. wiedii), and two sand cats (F. margarita), necropsied between June 1995 and March 1997 had large numbers of gastric spiral bacteria, whereas five large cats, including one African lion (Panthera leo), two snow leopards (P. uncia), one Siberian tiger (P. tigris altaica), and one jaguar (P. onca), necropsied during the same period had none. All of the spiral organisms from the nine small cats were histologically and ultrastructurally similar. Histologically, the spiral bacteria were 5-14 mum long with five to nine coils per organism and were located both extracellularly within gastric glands and surface mucus, and intracellularly in parietal cells. Spiral bacteria in gastric mucosal scrapings from the Canada lynx, one fishing cat, and the two sand cats were gram negative and had corkscrew-like to tumbling motility when viewed with phase contrast microscopy. The bacteria were 0.5-0.7 mum wide, with a periodicity of 0.65-1.1 mum in all cats. Bipolar sheathed flagella were occasionally observed, and no periplasmic fibrils were seen. The bacteria were extracellular in parietal cell canaliculi and intracellular within parietal cells. Culture of mucosal scrapings from the Canada lynx and sand cats was unsuccessful. Based on morphology, motility, and cellular tropism, the bacteria were probably Helicobacter-like organisms. Although the two margays had moderate lymphoplasmacytic gastritis, the other cats lacked or had only mild gastric lymphoid infiltrates, suggesting that these organisms are either commensals or opportunistic pathogens.

Abstract: The Katun River originates in the steppe of the Altai Mountains in Siberia. One of the major headwaters of the Ob River, the Katun is considered central to the culture of the indigenous Altaians. The Katun Valley contains large numbers of important cultural sites, dating from the Neolithic and representing some of the earliest human settlement in Russia. Modern-day Altaians still observe traditional ceremonies honoring the river and springs throughout the watershed and utilize traditional ecological knowledge in their management of the land and water resources. Russian and international scientists have identified the Altai Mountains as a region of high plant diversity and endemism, and as important habitat for endangered species such as the snow leopard. The Katun River itself contains species of threatened and endangered fishes, and its headwaters are part of the unusual Mongolian ichthyofaunal province that is characterized by high levels of endemism. The same regions are considered by the Altaian people to be special or sacred and are recognized by Western scientists as having great value for conservation. During the era of perestroika, a hydroelectric dam was to be built on the Katun. The large dam, a vestige of the earlier Soviet plan for the Project of the Century, would have devastated significant agricultural, ecological, recreational, and cultural resources. The indigenous Altaian people would have lost much of their sacred and cultural landscape. The Katun dam project united indigenous people, well-known Siberian writers, and scientists in protest, which became so heated that it engaged the international community, with lasting effects on Russian society. The magnitude of the protest illustrates the importance of the Altai Mountain region to all of Russia. The active participation of indigenous Altaians reflected their traditional willingness to take action against political decisions that negatively impacted the environmental, cultural, and religious values of their homeland. Their involvement also reflected the new wave of awareness under perestroika that underscored a greater respect and autonomy for indigenous peoples in Russia.