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The Australian tree Melaleuca quinquenervia (Cavanilles) Blake is an invasive weed in wetland systems of Florida. A biological control program targeting M. quinquenervia has resulted in the release of the gall forming midge Lophodiplosis trifida Gagne (Diptera: Cecidomyiidae). Populations of the introduced herbivore readily established at all 24 release sites across the weed's range in Florida, and there was no evidence that founding colony size (100,2,000, or 6,000 adults) influenced herbivore establishment or local population growth rates. Landscape level spread of L. trifida from release sites averaged nearly 6 km/yr, ranging as high as 14.4 km/yr. Prerelease host range testing predicted that L. trifida oviposits indiscriminately on test plant species but does not complete development on any of the test species, including congeners present in Florida. To test the predictability of these host range tests, L. trifida was released in a common garden consisting of 18 test plant species that were interplanted with M. quinquenervia. Plant species postulated to be at risk experienced no gall development by L. trifida while intermingled M. quinquenervia trees supported 704.8 (±158.5) galls per plant. Historically, many introduced Cecidomyiidae have limited effect on plant performance of target weeds because of recruitment of native parasitoids that disrupt biological control efficacy. In contrast to this trend, there has been no evidence to date that parasitoids are exploiting L. trifida in Florida. [ABSTRACT FROM AUTHOR]

Invasion by the Australian paperbark, Melaleuca quinquenervia, has degraded large areas of south Florida wetlands. Restoration of these wetlands requires the removal of expansive monocultures of this large tree while simultaneously curtailing its spread. Management strategies developed by federal and state agencies include biological control to halt the spread of this species and to prevent reinfestation of cleared areas. This requires biological agents able to reduce flowering, seed production, and growth while increasing mortality of seedlings and saplings. Two of the three introduced agents (Oxyops vitiosa Pascoe and Boreioglycaspis melaleucae Moore) partially meet these needs but outcomes are not spatially or temporally consistent. Thus, additional agents are needed. The bud-gall fly Fergusonina turneri Taylor, with its mutualistic nematode Fergusobia quinquenerviae Davies and Giblin-Davis, is actively being released but has not established. A fourth promising agent, the gall midge Lophodiplosis trifida Gagne, manifested an extremely narrow host range during laboratory testing. Oviposition was indiscriminant in caged environments. Small, incipient, unilocular galls were initiated on Melaleuca viminalis, but larval development ensued only on M. quinquenervia. The unilocular galls on M. viminalis did not grow and produced no adult flies. As a result, M. viminalis test plants suffered only minor cosmetic damage. Observations from both Australia and Florida attest to the ability of this midge to impede M. quinquenervia growth and kill small plants. Thus, L. trifida is safe to release and will likely contribute to management objectives for control of this pernicious wetland invader. [ABSTRACT FROM AUTHOR]

The article presents abstracts on veterinary medicine research topics which include one on the use of a modified Vinsot technique for partial phallectomy in horses, one on the severity of iatrogenic lesions between conventional and modified approaches in 16 equine cadaver forelimbs, and one on the factors associated with anhidrosis in horses in Florida.

Chinese tallowtree, Triadica sebifera (L.) Small (Malpighiales: Euphorbiaceae), is an invasive weed from southern China that is invasive in the Gulf states of the southeastern USA. One significant factor that contributes to the success of this weed has been the lack of herbivore species attacking it in the invaded range. However, the leafminer species Caloptilia triadicae Davis (Lepidoptera: Gracillariidae) was discovered feeding on Chinese tallowtree in Florida in 2008 and has now been found throughout much of the plant's invaded range. We monitored the seasonal abundance of C. triadicae populations and their associated parasitoids over 2 yr in Florida. Populations of C. triadicae peaked in Jun and Jul in 2013 and 2014. Parasitism averaged about 3.3% of larvae and pupae, with a peak of 12%. The most abundant parasitoid species was Goniozus sp. (Hymenoptera: Bethylidae) (76% of all parasitoid individuals reared) and, second, Brasema sp. (Hymenoptera: Eupelmidae) (18% of parasitoids). Due to specific niche requirements and the apparent exploitation of leaf mines by these parasitoid species, it is doubtful they will attack species being considered for biological control of Chinese tallowtree. [ABSTRACT FROM AUTHOR]

Background: This study was designed to determine if testing the first ~40 nasal washings (interval) each month for 1 year, could be used as an epidemiologic tool for seasonality and prevalence of respiratory viruses such as human metapneumovirus in an adult and pediatric population in the southeastern United States., Materials and Methods: Results of interval polymerase chain reaction (PCR) testing of 469 specimens for 8 viruses were compared with our current procedures using PCR, culture, or respiratory synctial virus antigen for all 7435 specimens (routine)., Results: One hundred thirty-six viruses out of 469 specimens (29.0%) and 1,495 viruses out of 7,435 specimens (20.1%) were identified by interval and routine testing, respectively. Seasonal detection varied among viruses and to some degree between interval and routine testing. A higher percent of positives and dual infections were detected by interval testing of pediatric specimens, likely due to the use of PCR for viruses commonly seen in this population. Human metapneumovirus was detected in both pediatric and adult specimens between January and August., Conclusions: Interval testing can be used to provide a snapshot of prevalence and seasonality of respiratory viruses, although as currently designed they may not be sensitive enough to identify the beginning of a specific virus season. Exclusive use of interval PCR testing identified several dual infections, including human metapneumovirus, throughout most of the year in Florida. A rapid turnaround time to results translates into improved infection control and improved patient care., (Copyright © 2013 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.)

The West-Indian manatee, Trichechus manatus latirostris, is a herbivorous marine mammal found in the coastal waters of Florida. Because of their endangered status, animal experimentation is not allowed. Therefore, a cell line was developed and characterized from tissue collected during necropsies of the manatees. A primary cell culture was established by isolating single cells from kidney tissue using both enzymatic and mechanical techniques. Primary manatee kidney (MK) cells were subcultured for characterization. These cells were morphologically similar to the cell lines of epithelial origin. An immunocytochemistry assay was used to localize the cytokeratin filaments common to cells of epithelial origin. At second passage, epithelial-like cells had an average population-doubling time of 48 h, had an optimum seeding density of 5 x 10(3) cells/cm2, and readily attached to plastic culture plates with a high level of seeding efficiency. Although the epithelial-like cells had a rapid growth rate during the first three passages, the cloning potential was low. These cells did not form colonies in agar medium, were serum dependent, had a limited life span of approximately nine passages, and possessed cell-contact inhibition. These data suggest that the cells were finite (noncontinuous growth), did not possess transformed properties, and were of epithelial origin. These cells are now referred to as MK epithelial cells.

In 1996, at least 149 manatees (Trichechus manatus latirostris) died in an unprecedented epizootic along the southwest coast of Florida. At about the same time, a bloom of the brevetoxin-producing dinoflagellates, Gymnodinium breve, was present in the same area. Grossly, severe nasopharyngeal, pulmonary, hepatic, renal, and cerebral congestion was present in all cases. Nasopharyngeal and pulmonary edema and hemorrhage were also seen. Consistent microscopic lesions consisted of catarrhal rhinitis, pulmonary hemorrhage and edema, multiorgan hemosiderosis, and nonsuppurative leptomeningitis. Immunohistochemical staining using a polyclonal primary antibody to brevetoxin (GAB) showed intense positive staining of lymphocytes and macrophages in the lung, liver, and secondary lymphoid tissues. Additionally, lymphocytes and macrophages associated with the inflammatory lesions of the nasal mucosa and meninges were also positive for brevetoxin. These findings implicate brevetoxicosis as a component of and the likely primary etiology for the epizootic. The data suggest that mortality resulting from brevetoxicosis may not necessarily be acute but may occur after chronic inhalation and/or ingestion. Immunohistochemical staining with interleukin-1-beta-converting enzyme showed positive staining with a cellular tropism similar to GAB. This suggests that brevetoxicosis may initiate apoptosis and/or the release of inflammatory mediators that culminate in fatal toxic shock.

Samples of serum, liver, kidney, and heart were collected for selenium analysis from 174 white-tailed deer (Odocoileus virginianus) in southern Florida (USA), 1984 to 1988, to determine the selenium status of these animals. Deer were obtained from eight sites and classified by five age-class groups. For serum and the three tissues analyzed, selenium concentrations varied significantly (P < 0.001) among sites. Differences between years (P < 0.0004) were found for heart and kidney, age-class (P < 0.004) for kidney and season (P < 0.02) for liver. Low selenium concentrations were evident, in that 75% of all serum samples analyzed contained less than the critical concentration (< 0.06 ppm) by livestock standards, with 50% of serum samples less than 0.03 ppm, evidence of a severe deficiency. Likewise, tissue selenium concentrations (dry basis) were below critical livestock concentrations in 13% of the liver samples (< 0.25 ppm), 36% in kidney (< 3.0 ppm) and 19% in heart (< 0.15 ppm). Based on serum and tissue data, selenium dietary intake was low and may have been deficient for white-tailed deer in southern Florida.

Three morphologically distinct types of sarcocysts (I, II, and III) were identified by light microscopy in tongues from 403 white-tailed deer (Odocoileus virginianus) collected in Florida (USA) over a 7-yr-period. Based on electron microscopy of representative examples of these sarcocysts, there were four distinctive wall structures. We concluded that one of these (Type I) was representative of Sarcocystis odocoileocanis and another (Type III) was representative of an unnamed species previously described from white-tailed deer in Montana. Type II could be divided further into two forms (IIA and IIB) that may represent two underscribed species or developmental stages of the same species. Sarcocystis odoi, another previously recognized sarcosporidian from white-tailed deer, was not found. Sarcocysts of Types I and II were distributed nonrandomly in tongue muscle, being more common in the basal portion, whereas Type III was distributed randomly throughout the tongue. Single infections (one of the three types) accounted for 63% of the infected deer, while double infections occurred in 28% and triple infections in 4%. Types I and II were found in deer throughout the state, but Type III occurred only in deer from southern Florida. In 1988 and 89, the statewide prevalences for Types I, II, and III were 57, 20, and 6%, respectively. Prevalences of Type I ranged from 94% in the panhandle region (northern Florida) to 34% in the southern part of the state. Prevalences of all three types increased with age.

Sarcocysts of Sarcocystis sp. were found in the striated muscles from 11 of 14 wild Florida panthers (Felis concolor coryi) and four of four cougars (two wild F. concolor stanleyana and two captive F. concolor of undetermined subspecies). The common occurrence of sarcocysts in muscles of top carnivores such panthers and cougars is unexplained. This stage of the life cycle is normally confined to the muscles of the prey species. Because large felids are rarely preyed upon, it is unlikely that a species of Sarcocystis has evolved using large cats as intermediate hosts. Therefore, the presence of these sarcocysts might be an indication of immune compromise in these felids, enabling the atypical development of the sarcocysts.