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The article reports on the result of the study which assesses the prevalence of Mycobacterium (M) bovis infection in brushtail possums, Trichosurus vulpecula, that were not diagnosed for bovine tuberculosis in New Zealand. The study was conducted on tissues taken from possums belonging to four populations infected with the bacteria. It was found that possums with no macroscopic lessions show reduced potential of declaring the animals free from the disease.

The distribution and numbers of rook nests and rookeries in Hawke's Bay, northern Wairarapa and Manawatu were recorded in 11 surveys undertaken between 1969 and 1986. The area inhabited by rooks, as indexed from the number of 10 000 m grid squares occupied in each survey, increased from 61 in 1969 to 102 in 1984. The total number of nests reached a peak of 12 424 in 1978 and fell to 5635 in 1986, and the mean number of nests per rookery fell from 73 in 1969 to 22 in 1986. The rook population thus changed over the 1969-86 period from a dense population centred in large rookeries in a small area, to a less dense population in small rookeries scattered over a much larger area. The geographic spread was mainly to the south of the Heretaunga Plains to north of Masterton. While these changes in distribution occurred concurrently with initial rook control, there is no direct evidence of a causal relationship. Agricultural practices also changed over that time, and the rook population had been spreading through Hawke's Bay for many decades. Ground baiting with the avicide DRC-1339 between 1971 and 1985 poisoned nearly 86 000 rooks across their range in the study area. This reduced the estimated damage to crops and pasture south of Hastings from $98,000 in 1969 and $154,000 in 1970 to almost nothing by the 1980s, as indicated by complaints received by DSIR and the Pest Destruction Boards and anecdotal evidence. DRC-1339 was also applied directly to rook nests in an attempt to eradicate rooks from northern Hawke's Bay between 2002 and 2006. While more than 50% of rookeries were destroyed each year using this technique, this reduction was largely offset by the establishment of new rookeries and the re-colonising of extinct ones. Non-target deaths during rook control were largely confined to black-backed gulls (Larus dominicanus) and Australian magpies (Gymnorhina sp.). These species made up only 1% of the total kill, and were only recorded during ground-based operations. While the Hawke's Bay rook population is now widespread, the low concentration of rookeries and smaller rookery sizes mean that rooks do not currently pose the economic threat incurred by individual farmers in the 1960s and 1970s. The current rook population structure does not warrant large-scale control efforts. [ABSTRACT FROM AUTHOR]

Four control operations, each with paired pre-feed and no-pre-feed treatments, and comprising two baited with carrot and two with cereal, provided strong support for the hypothesis that pre-feeding produces higher possum kills than no pre-feeding. In these replicates, even where high kills were achieved, the modelled two- to three-fold extension of the period of population depression given by pre-feeding was sufficient to warrant the expense of the additional bait sown. The benefits of pre-feeding were clear-cut, and were greatest where poorest kills were achieved, irrespective of bait type. Pre-feeding is thus likely to reduce the probability of failure and should be considered a form of operational insurance. [ABSTRACT FROM AUTHOR]

Microbial adaptations associated with extreme growth environments, including high temperatures and low pH, are of interest to astrobiologists and origin of life researchers. As part of a survey of microbial lipids present in terrestrial geothermal settings, we examined four silica sinters associated with three different hot spring areas of the Taupo Volcanic Zone (TVZ), New Zealand. Dominant bacterial lipids include free fatty acids, 1,2-diacylglycerophospholipids, 1,2-di- O-alkylglycerols, 1- O-alkylglycerols, wax esters, alkanols, alkan-1,2-diols and various hopanoids, whereas dominant archaeal lipids include both archaeol and glycerol dialkyl glycerol tetraethers. Although many of these compounds occur in other settings, in the TVZ sinters their distributions (with high abundances of β-OH fatty acids and high-molecular-weight (> C18) fatty acyl components) and carbon isotopic compositions (ranging from −40 to +4, with up to 25 variability in a single sample) are unusual. In addition, we have identified a range of unusual compounds, including novel macrocyclic diethers and hopanoids. The distributions of these compounds differ among the study sites, suggesting that, where preserved in ancient sinters, they could serve as an important tool in studying past hydrothermal environments. [ABSTRACT FROM AUTHOR]

There are several newer intravenous iron formulations to treat iron deficiency and its anaemia. Its use in the primary care setting has been infrequent compared to tertiary centres, due to historical concerns such as anaphylaxis. There is a lack of overall comparison among the intravenous formulations of iron. Compared to oral iron therapy, the newer intravenous formulations, which allow a complete or near-complete replacement in a single sitting of 15-30 minutes, have an improved safety profile with better tolerability, efficacy and effectiveness. They are suited for administration in the primary care setting. The four non-dextran formulations (ferric carboxymaltose, iron sucrose, iron isomaltoside and ferumoxytol) share an equal or near equal efficacy and safety profile. This article also outlines how to provide iron infusion safely and effectively in the community., Competing Interests: Nil.

Debates about identifying and naming lesbians in history and how to characterize relationships between women in earlier historical contexts have been passionately contested since publication of Carroll Smith-Rosenberg's (1975) essay "The Female World of Love and Ritual." Spurred by Adrienne Rich's influential concept of a lesbian continuum and more recent gender-crossings in Queer and Trans-theory, charting the ambiguous spaces of desire is a highly charged political act. Together, these debates pose significant challenges for feminist historians researching women whose lives disrupted any neat correspondence between sex, gender, and sexuality. This article traverses these issues in relation to Amy Bock, infamous as a criminal confidence artist and cross-dresser at the turn of the twentieth century and claimed in recent times as lesbian. Amy herself pleaded an inherited mental instability; the authorities at the time agreed she was a habitual criminal. Mad, bad, or lesbian? Or was she simply unconventional in her gender and sexuality? It is argued that how we approach these questions potentially tells us more about the desires of the researcher than those of our subjects.

Aim: To determine the effect of fertility control on the rate of transmission of bovine tuberculosis (Tb), caused by Mycobacterium bovis, in brushtail possums (Trichosurus vulpecula)., Methods: At two study sites with a history of Tb infection in the resident possum population, a sample of adult male and female possums (n=50), determined by palpation to be Tb-free, was surgically sterilised by gonadectomy. A sample of untreated Tb-free male and female possums (n=54) served as controls. Each study site was trapped every 2 months over a 3-year period, and the Tb status of the individuals in the trial assessed. At the conclusion of the trial, all remaining experimental individuals were killed, necropsied and examined for characteristic lesions typical of Tb. The rate of transmission of Tb infection was estimated using the incidence of tuberculous cases in the experimental animals and comparing it between sites, sex and sterilisation treatment., Results: Sterilisation by gonadectomy resulted in a reduction in the rate of transmission of Tb in male possums by 53%, but a corresponding increase in sterilised females for reasons that are still unclear. However, this interaction was statistically weak (p=0.10). When the sexes were combined, there was no overall effect of sterilisation on the rate of transmission of Tb (p=0.43). Sterility treatment notwithstanding, there was a highly significant difference in the rate of transmission between the sexes (p=0.01), being almost one order of magnitude higher in untreated males compared with untreated females., Conclusions: Although lacking strong statistical support, these results suggest that fertility control that targets endocrine control of fertility may provide some additional benefits for disease control over that achieved by reductions in population density, by reducing the rate of transmission of M. bovis in male possums. However, additional studies are needed to confirm the validity of these results. The large difference in the rate of transmission of M. bovis in untreated males compared with untreated females suggests that transmission of Tb among males may be an important driver of the dynamics of Tb infection in possums.

Aim: To determine the trap-catch index (an estimate of abundance) of brushtail possum (Trichosurus vulpecula) populations infected with bovine tuberculosis (Tb; Mycobacterium bovis) that must be achieved, and the length of time such an index must be maintained, for Tb to be eliminated from possum populations and adjacent livestock., Methods: Between 1997-1998 and 2000-2001, trap-catch surveys of possum populations naturally infected with Tb and subjected to population-control measures were undertaken at four forest sites and two farmland sites. At the same time, possum carcasses were collected at these sites and their Tb status determined, and all contiguous cattle and deer herds were Tb tested and abattoir slaughter data for these herds were interrogated., Results: Trap-catch surveys indicated that numbers of possums on the farmland sites surveyed were usually very low and well below the control targets set (i.e. a 5% trap catch or approximately 0.5-1 possum/ha) for the study. In contrast, trap-catch surveys undertaken in forest sites indicated possum numbers were more variable, and often recovered rapidly from control operations to exceed control targets within 1-3 years. The annual rate of recovery of possum populations in half of the forest population surveys undertaken exceeded published intrinsic rates of increase for possums. The overall prevalence of Tb in possum populations was < or =1.9% at 5/6 sites, and was 6.5% at the sixth site. Juvenile possums infected with Tb were trapped within but near the edge of control zones and appeared to represent an immigrant source of infection. Mature infected possums survived control operations apparently by having home ranges in uncontrolled patches within control areas. Infection in possums appeared to be eliminated from one study site by the intensive control undertaken, but elimination at other sites appeared less likely. Levels of Tb in livestock on or adjacent to the study sites fell by at least 50% during the study, and cattle in one area tested clear for the first time in 20 years., Conclusions: Initial control of possums in forest appeared to achieve national control targets set by the Animal Health Board (AHB), despite trap-catch data often providing misleading population estimates. Such targets were often exceeded within 1-3 years. By comparison, possum control on farmland appeared to maintain populations at very low levels, while control on forest margins maintained populations at intermediate levels. Control was least effective in deep forest where human access was most difficult. Intensive population control measures appeared to have led to a reduced incidence of Tb in livestock at 3/4 sites, and elimination of Tb in livestock at one site. This result supports modelling studies that predict the eradication of Tb from possums through ongoing intensive control and may explain the lower success achieved with earlier less-intensive possum control.

Bovine tuberculosis (Tb) is the most important disease of livestock in New Zealand, and it puts at risk the nation's trade in dairy, beef and venison products. Elimination of the disease from livestock is based on a herd test and slaughter programme and carcass inspection at abbatoirs. However, this programme has not been as successful as expected, because the disease also occurs in wild or feral animals acting as vectors of the disease to livestock. Brushtail possums are the major wildlife vector and self-sustaining maintenance host of Tb, and play a role analogous to that of the badger in Great Britain. In contrast, some deer species and ferrets may act as vectors of the disease, but their role in transmitting Tb to livestock is unclear. Hedgehogs, pigs, cats, sheep and goats are now considered to be amplifier hosts, and spread the disease to other species only when inspected or their carcasses scavenged. In the absence of infected possum populations, these species do not appear to be capable of maintaining the infection in their own populations and are not thought to be involved in the maintenance of Tb in livestock. Tuberculosis has also been recorded from stoats, hares, and a rabbit, but the level of infection recorded in their populations indicates these species are unlikely to spread the disease to other animals and hence are not involved in the transmission of Tb to livestock., (Copyright 2001 Harcourt Publishers Ltd.)