A comparative cervical skin test using 1.0 mg/ml bovine purified protein derivative and 0.5 mg/ml avian purified protein derivative was evaluated as a method for detecting tuberculosis in farmed deer. A positive comparative cervical skin test reaction was defined as a bovine response with a 2 mm or greater increase in skin thickness which was greater or equal to the avian response. Estimates of the sensitivity of the comparative cervical skin test were obtained from a series of experiments conducted on 60 deer intratracheally inoculated with Mycobacterium bovis. Prior tuberculin skin testing was found to suppress the skin reactivity to a subsequent comparative cervical skin test. This effect was most pronounced at short intervals of 3-7 days, but could still be measured 60 days after the previous test. When the test interval was greater than 60 days, the sensitivity of the comparative cervical skin test was 91.4%. The specificity of the comparative cervical skin test was 98.7% when 1157 deer from 17 uninfected herds with a history of nonspecific skin test reactions were examined. There was no statistical difference in the mean skin thickness increases of three groups of infected animals tested with 2 mg/ml, 0.2 mg/ml and 0.02 mg/ml of bovine purified protein derivative respectively.

A sample survey of anthelmintic usage and farmers; drenching policies was conducted on 614 sheep farms, in the North and South Islands, selected from among those carrying 1500 or more breeding ewes. The survey was based on information for the 1978179 and 1979/80 farming years recorded on questionnaires completed during personal interviews between Livestock Officers and the farmers concerned. Results show that there were no significant between-Island differences in mean drenching frequencies for any age class of sheep. In 1979/80, the overall New Zealand drenching frequencies were 6.3 for lambs, 1.8 for 1-2-year-olds and 1.2 for sheep older than 2 years. Of the farmers surveyed, 20% did not drench 1-2-year-old sheep and 29% did not drench sheep older than 2 years. There were also no between-Island differences in timing of drenches and alternation of drench brands. Sixty-nine per cent of the farmers followed a pre-determined drenching programme whereas 27% stated that they drenched if and when necessary. For lambs, some drenching was carried out in all months of the year hut fewer farmers drenched during the mid-winter to mid-spring period (July-October). Older stock were drenched in all months also but there was a general acceptance by farmers of the practices of pre-tupping and pre or post-lambing drenching. At the time of the survey, 48% of the farmers were using three or more brands of drench with a maximum of nine. Analysis of data relating to brands of drench used shows that whereas 39% of the farmers w,ere alternating drench families [i.e. benzimidazoles (BZ) c.f. non-benzimidazoles (NBZ)] within a single farming year, only 3% were practising a strict alternation of drench families between years. General comments by the farmers surveyed indicate a disturbing degree of misunderstanding and misconception regarding the properties and limitations of current anthelmintics. The survey also revealed a lack of appreciation of the rationale of prophylactic (;preventive;) parasite control. These aspects are discussed in relation to currently recommended control strategies and the problem of anthelmintic resistance.

Two groups of 26 red deer (Cervus elaphus) were tuberculin skin tested for 41 weeks at three and six week intervals respectively, except at 17 weeks when the internal was two and five weeks. Seventeen weeks after the start of the experiment 36 deer were inoculated intratracheally with Mycobacterium bovis, and the remaining 16 were run in-contact. At six weeks post inoculation, 35 of the 36 inoculated deer reacted to the skin test with a mean skin thickness difference (STD) of 6.3 mm. In inoculated deer further testing led to a suppression of skin sensitivity which was significantly greater in the three-weekly tested group. There was no statistical difference in skin thickness response between 1 and 2 mg/ml bovine purified protein derivative (PPD). Of 454 tests on noninoculated deer (noninfected), 107 produced reactions. These reactions were small and 96% had a STD of less than 2 mm.

A total of 17175 lambs livers and 9322 sheep livers randomly selected from animals slaughtered at export meatworks in 1984 were examined for liver fluke infection. Futher sheep livers from some regions were examined in 1985. The origins of the animals examined were recorded and used to estimate regional prevalences of infection. Infection in lambs was first detected in February and the prevalence increased after then; the mean prevalence in July was 2.7% in the North Island and 2.0% in the South Island . In adult sheep in 1984, regional prevalences in the North Island ranged up to 16.9% (>10% in South Auckland, East Coast, Hawkes Bay and Taranaki) and in the South Island up to 29.4% in Westland (18% in Nelson). The overall prevalence in the North Island was 7.5% and in the South Island 1.1%, about double that recorded in 1969. Data for 1985 were incomplete but prevalences tended to be higher than in 1984. From April 1984 to August 1985 the origins of all lines of cattle with fluke-affected livers were recorded in all abattoirs and export meatworks. During 1985, 16 147 infected lines were traced to all countries in the North Island, with over 60% from the Whangarei, Hamilton, Taumarunui, Gisborne and Hastings areas. In the South Island , over 90% of 1585 infected lines originated from Westland, Waimea, Grey, Inangahua and Buller Counties.