Durability of a novel durable bait for control of subterranean termites (Isoptera: Rhinotermitidae): results of five-year field aging studies

A durable termite bait containing 0.5% noviflumuron was evaluated for physical durability, retention of active ingredient, consumption by termites, and toxicity to termites over 5 yr in field studies at locations in Indiana, Mississippi, and South Carolina. Plots in Indiana and Mississippi included both natural rainfall and irrigated plots, while plots in South Carolina received only natural rainfall. Samples collected every 3 mo for the first 4 yr were evaluated for consumption with a 7 d no-choice bioassay using Reticulitermes flavipes (Kollar). Consumption and toxicity of 5 yr samples were evaluated in similar bioassays conducted for 42 d. Durable baits received from field sites had some cracking, and a small amount of external flaking, but no major deterioration based on visual observation. There were no significant differences in noviflumuron concentration over the 5-yr period and no trend toward reduced concentrations of noviflumuron over time. Consumption of aged durable baits over 4 yr was variable, but termites usually consumed more aged durable bait than fresh durable bait and the differences were frequently significant. There were some exceptions, but termites consumed significantly more fresh durable bait than aged durable bait in only 4% of observations. When 5 yr samples were evaluated, consumption was lowest for fresh durable bait and termites consumed significantly more aged durable bait from irrigated plots in Indiana and from both natural and irrigated plots in Mississippi than fresh durable bait. Survival of termites fed blank durable bait was significantly higher than that for termites fed any of the baits containing noviflumuron and there were no significant differences in survival among the noviflumuron durable baits. Our results suggest that the bait would be durable for at least 5 yr and possibly longer under most environmental conditions.

A high frequency of male determining factors in male Musca domestica (Diptera: Muscidae) from Ipswich, Australia

The male sex determining factor (M) in the house fly is linked to the Y chromosome in the ancestral condition, but can also be linked to another chromosome (I-V or X). However, descriptions of the linkage and frequency of M factors in different populations throughout the world are vastly incomplete. We collected house flies from a dairy in Ipswich, Australia, and determined that M was linked to chromosomes II, III, IV, and Y. Most males (69.8%) were homozygous for M on autosome II and/or III, and 92.3% of the males had multiple M factors. In all, there were 13 different male genotypes found. The high frequency of M, the presence of M on four different linkage groups, and the large number of male genotypes found in this population make it unique relative to other populations of house flies that have been examined.

Frequencies of the pyrethroid resistance alleles of Vssc1 and CYP6D1 in house flies from the eastern United States

House flies were collected from four dairies in Maine, New York, North Carolina, and Florida, where high levels of resistance to permethrin have been documented. Regions of two genes, CYP6D1 and Vssc1, having alleles that confer resistance to permethrin (and other pyrethroids) were analysed from individuals at each collection site. The combinations of resistance alleles for Vssc1 and CYP6D1 were highly variable between each state. The resistance allele CYP6D1v1 was found at a high frequency (0.63-0.91) at all sites. Individuals homozygous susceptible for CYP6D1 were very rare and detected only at the dairy in Maine. In addition to the typical Vssc1 mutation responsible for resistance, kdr (L1014F), we also identified individuals with a L1014H mutation. Although house flies homozygous for the L1014H mutation had a lower level of resistance to permethrin, compared to L1014F, the H1014 resistance allele was frequently detected. No individuals with the super-kdr allele (M918T + L1014F) were detected from the field collections. The intron 3 bp downstream of the kdr mutation was found to be extremely variable, providing an opportunity to reconstruct a phylogeny of Vssc1 alleles. Based on this analysis it appears the kdr-his mutation had multiple evolutionary origins, but that the kdr mutation may have had a single origin. The impacts of these findings on resistance management are discussed.

Wrist arthrography: review and comparison of normals, rheumatoid arthritis and gout patients

Bilateral wrist arthrograms performed on a randomly selected population of 100 adult males revealed an unexpected high prevalence of communications among the three wrist compartments. These findings warrant reassessment of wrist arthrographic criteris for synovial involvement of rheumatoid arthritis. Midcarpal joint extension correlated with increasing age and occupational trauma, suggesting a degenerative or "wear and tear" mechanism in the breakdown of the delicate interosseous intercarpal ligaments. Such extension was also found to a greater than expected frequency in gout. Radioulnar joint extension correlated with acute trauma secondary to wrist sprains or fractures, presumably through tears in the tough triangular fibrocartilage. Such extension was also found to a greater than expected frequency in RA. While midcarpal extension and inferior radioulnar extension correlate with gout and RA, respectively, their occurrence in a random adult male population is so frequent (as is three compartment communication) as to obviate their diagnostic value. However, synovial corrugation and lymphatic visualization were seen only in the wrists of patients with diagnosed inflammatory arthritic conditions and may have potential diagnostic significance. Selected anthropometric variables were analyzed by age in this randomly selected adult male population and compared with the gouty and RA patient groups. Significant continuously decreasing grip strength and hand mineralization occurred with age, which was opposite to the trend for osteoarthrosis. The hematocrit, erythrocyte sedimentation rate, and serum uric acid were impressively stable until the ninth or older decades, at which time a significant increase in sedimentation rate and decrease in hematocrit were found.