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The objective of this study was to determine the therapeutic and residual efficacy of a topically applied combination of cyphenothrin (40 %) and pyriproxyfen (2 %) against the tick Haemnphysalis elliptica and the flea Ctenocephalides felis on dogs. Twelve dogs were infested with 50 ticks 2 days before they were treated and with approximately 100 fleas 6 days before treatment and again 2 days before treatment and with 50 ticks and approximately 100 fleas at weekly intervals thereafter. They were ranked according to their flea counts and sex 5 days before treatment and randomly allocated to an untreated control group of 6 dogs and a treated group of 6 dogs. Ticks and fleas were collected from the dogs 48 h after treatment and 48 h after each infestation and live and dead ticks and live fleas were counted. The counts of ticks and fleas were transformed to geometric means, and efficacy was calculated by comparing these means. The product had a therapeutic efficacy of 83.1 % against H. elliptica and 97.5 % against C. felis 2 days after treatment. The residual period of protection during which efficacy was ≥ 90% was 5 weeks for both H. elliptica and C. felis. [ABSTRACT FROM AUTHOR]

The efficacy of orally administered powdered aloe juice (Aloe ferox) was evaluated against ticks on cattle and against ticks and fleas on dogs. Twelve calves were each infested over a 25-day period with approximately 4000 larvae of Rhipicephalus (Boophilus) decoloratus and allocated to 3 groups of 4 calves each. Three days after the last larval infestation and daily for 22 days thereafter, the calves in 1 group were fed 5 mg/kg body weight and those in another 25 mg/kg body weight of powdered aloe juice incorporated in game maintenance pellets, while the animals in the 3rd group received only pellets. Detached female ticks were collected daily and counted and the weights and the fertility of groups of 50 engorged female ticks collected from the animals were ascertained. The powdered aloe juice in the game maintenance pellets had no effect on the tick burdens of the calves or on the fertility of the ticks. Six dogs, in each of 2 groups, were treated daily for 15 consecutive days, commencing on Day -5 before the 1st tick infestation, with either 0.39 g or 0.74 g of powdered aloe juice, administered orally in gelatin capsules, while a 3rd group of 6 dogs served as untreated controls. All the dogs were challenged with Haemaphysalis leachi on Days 0 and + 7, and with Ctenocephalides felis on Days + 1 and + 8, and efficacy assessments were made 1 day after flea and 2 days after tick challenge, respectively. Treatment was not effective against ticks or fleas on the dogs.

This study was done to compare the collection of cat urine, for phosphate concentration determination, by catheterisation with that via a proprietary cat litter (Katkor). The passage of urine through the litter or its retention in the litter for a period of 2 hours did not affect the concentration of phosphates compared with that of the original sample. Apart from a small volume of urine trapped in the litter by capillary action, and some urine adhering to the funnel in which the litter was placed, the litter proved to be an excellent medium for routine urine collection from cats, and more especially as an alternative to catheterisation when regular collection from a particular cat is required.

Adult biting lice Damalinia limbata (Gervais 1844) were most numerous on Angora goats in southwestern Free State Province from November to May with the smallest numbers present during August. Nymphs were most numerous from January to March with the smallest numbers present during July. The largest proportion of adult lice was present on the ventral surface of goats during winter, when population numbers were lowest, and the largest proportion of nymphs during summer, when population numbers were highest. Infestation did not affect the body weight of goats, but adversely affected both the quantity and quality of mohair produced. A single treatment with deltamethrin, applied as a pour-on along the mid-line of the backs of the goats, effectively controlled infestation and resulted in a significant increase in mohair production compared with untreated goats. Deltamethrin sprayed along the sides of the animals was equally effective in controlling infestation.

The efficacy of 2 sets of collars (Kiltix Collar, Bayer AG), containing different plasticisers and impregnated with the acaricides flumethrin (2.25%) and propoxur (10%), was compared against adult Rhipicephalus sanguineus on experimentally infested, kennelled dogs. Thirty individually penned dogs were infested with 25 male and 25 female, unfed R. sanguineus. On the following day they were allocated to 3 groups of 10 dogs each on the magnitude of their tick burdens. Two days after infestation, medicated collars containing 1 of the plasticisers were fitted to 10 of the dogs and similar collars containing the other plasticiser were fitted to 10 others. The remaining 10 dogs were the untreated controls. Seven and 28 days after having fitted the collars, all dogs were re-infested with 50 unfed adult ticks of both sexes, and again at approximately 28-day intervals up to the 5th month, and then at approximately 14-day intervals during the 6th month. Efficacy was determined by comparing the mean number of live, attached ticks on the untreated control group with those on the collared dogs 2 days after each re-infestation. Immediate efficacy of the collars (Day +2) was > 95%, and residual efficacy was > 98% up to and including Day +114, and > 93% up to Day +170 on both groups of collared dogs. The mean tick counts on the 2 groups of collared dogs did not differ significantly (P < 0.0001) for any of the assessment days.

The susceptibility of the larval offspring of engorged female Boophilus decoloratus, and of the engorged females, collected from cattle on the dairy farms Brycedale, Sunny Grove and Welgevind in the Eastern Cape Province, South Africa, was tested against the acaricides amitraz, chlorfenvinphos and cypermethrin. Resistance was determined by means of the Shaw Larval Immersion Test (SLIT) for larvae and the Reproductive Estimate Test (RET) and Egg Laying Test (ELT) for adults. At Brycedale the tests all indicated resistance to chlorfenvinphos, and RET and ELT indicated resistance to amitraz and emerging resistance to cypermethrin. At Sunny Grove, B. decoloratus was resistant to cypermethrin using SLIT and exhibited emerging resistance to chlorfenvinphos with SLIT and to cypermethrin with both RET and ELT At Welgevind, resistance was recorded against chlorfenvinphos (SLIT) and against cypermethrin (ELT), and emerging resistance against permethrin (RET). The results obtained with RET and ELT were generally comparable, but often differed from those obtained with SLIT. Resistance could be detected within 7 days with ELT compared to 42 days with RET and 60 days with SLIT.

Sheep scab mites, Psoroptes ovis, collected from a Merino donor sheep, were used to infest Merino and Dorper sheep, and Angora and Boer goats. Mites were placed on the sheep on 1 or 2 occasions and on 5 occasions on the goats. All the animals were examined at regular intervals for the presence of scab lesions and living mites. Both sheep breeds developed lesions, but those on the Merino sheep were always larger than those on the Dorper sheep at the same intervals after infestation. None of the goats developed lesions or showed signs of irritation, or harboured any mites.

A single Merino sheep, artificially infested with the sheep scab mite, Psoroptes ovis, and a similarly infested Dorper sheep were placed with 9 uninfested Merino or 9 uninfested Dorper sheep respectively during winter and the rate of spread of infestation on the uninfested sheep observed. The same procedure was repeated in summer. It took 14 and 8 weeks respectively in winter before all sheep in the 2 groups displayed lesions of sheep scab, whereas in summer it took 10 and 12 weeks before all sheep had lesions.

The objectives of this study were to determine the influence of application site and sheep breed on the efficacy of a flumethrin (1% m/v) solution for the control of 'bont'-legged (Hyalomma spp.) and red-legged ticks (Rhipicephalus evertsi evertsi). This study was conducted from November 1996 to February 1997 on 3 farms in the southwestern Free State Province. Two trials were conducted on Dorper sheep and 2 on Merino sheep. For each specific application 30 sheep were selected and allocated to 3 groups of 10 animals each using randomisation through minimisation, with pre-treatment total tick count as only criterion. Groups consisted of an untreated control group, a group treated with 3 ml of a flumethrin (1% m/v) solution applied only to the anogenital region, and a group treated at a dose rate of 1 mf flumethrin (1% m/v)/5 kg host body mass. The total dose volume for animals in the last group was divided into 3 equal parts and applied to the brisket/axillae, groin and anogenital regions respectively. Animals grazed under extensive farming conditions and were infested by ticks that occurred naturally in the environment. Ticks were counted and removed weekly over a 6-week period. In all 4 trials, Rhipicephalus e. evertsi was the dominant tick species, followed, in 3 of the trials, by Hyalomma spp. Efficacy (%) of control against ticks for Dorper sheep, treated only on the anogenital region, was variable, ranging between 29.5 and 97%. In Merino sheep the efficacy values ranged between 23.1 and 90 %. The site-spcific (anogenital region) efficacy of control against ticks infesting Merino sheep was in general 100% or almost 100%. In Dorper sheep the efficacy values were >80 % for 3-5 weeks. The efficacy (%) of control against ticks for sheep treated on the brisket/axillae, groin and anogenital regions was always higher compared to sheep treated only on the anogenital region. In Dorper sheep, efficacy of control was >80 % for up to 4 weeks and in Merino sheep >80 % for 6 weeks.

Fleas cause allergic dermatitis in cats and dogs and therefore warrant control. It has been demonstrated previously that there is marked inhibition of the development of the immature stages of the cat flea Ctenocephalides felis on fleece blankets exposed to cats treated with imidacloprid. This study reports on the efficacy of imidacloprid in suppressing adult flea emergence in carpet exposed to treated cats. Circular discs of carpet pre-seeded with flea eggs and larvae were exposed to 6 untreated control and 6 topically treated (imidacloprid 10% m/v) cats 1 to 2 days after treatment and subsequently fortnightly for 6 weeks. Exposure times on alternate days were either 1 or 6 hours. Adult flea yield from carpets was determined 35 days after exposure. Differences between flea yield on control carpets and those exposed for 1 hour were significant only for days +1 and +14. For the 6-hour exposure, differences were significant at all times except on Day +43. The ability of imidacloprid to suppress the yield of adult fleas on carpets (6-hour exposure) steadily declined from 82 % (Day +2) to 12% (Day +43). For the 1-hour exposure it varied inconsistently between 0 and 83% over the 6-week study period.

The sites of attachment of female Karoo paralysis ticks (Ixodes rubicundus) were determined on Friesian, Bonsmara and Nguni cattle in the south-western Orange Free State. The largest proportion of the ticks (> 30%) attached to the forelegs and shoulders of the cattle. Contrary to the findings on small stock, no significant differences in the preferred sites of attachment were evident between the breeds of cattle.

A number of young Friesian oxen were slaughtered (one at a time) for parasite recovery for 12 consecutive months, from April 1987 to March 1988, on a farm in the Fauresmith district of the south western Orange Free State. A total of 5 ixodid and one argasid tick species, 2 lice species, plus one nematode species and one cestode species, were recovered. Peak numbers of adult Hyalomma marginatum rufipes were present from November 1987 to February 1988, while the largest numbers of Hyalomma truncatum were recovered during September 1987 and from November 1987 to January 1988. Adult Ixodes rubicundus were recovered only during April and June 1987. Adult ticks of a Rhipicephalus sp. near R. punctatus were present during April and from September to November 1987 and in January 1988. No pattern of seasonal abundance was evident for the other tick species, the lice or the helminths.

With the exception of October, when no collections were made, adult ticks were collected at weekly intervals from February 1986 to January 1987 from 20 randomly selected sheep out of a flock of 60. Ixodes rubicundus was the most abundant tick and was present from April to September with a peak during May. Hyalomma marginatum rufipes was the next most numerous tick. It was recovered throughout the year with peak burdens being recorded from November to April. Small numbers of a Rhipicephalus sp. (near R. pravus) were also collected. These exhibited a major peak during February and a minor peak during August. A dipping programme to prevent the paralysis caused by I. rubicundus and the Rhipicephalus sp. (near R. pravus) is suggested.

Paralysis of Angora goat kids caused by adult ticks, which most probably belong to an undescribed species of the Rhipicephalus pravus group, is described. Confirmed cases of paralysis occurred in the south-western Orange Free State between the second half of September and the first half of November as well as during the first half of February. The mean female tick burdens (mean = 21.4) of paralysed Angora kids were significantly higher than those of healthy kids (mean = 4.4). The predilection attachment site of the adult ticks was the ears of the goats. The elephant shrew Elephantulus myurus is a preferred host of the immature stages whereas the scrub hare Lepus saxatilis serves as an important host for the adult ticks.