Some observations on the sero-prevalence of heartwater and tick infestation in Zambian goats

A survey was carried out to define the distribution of heartwater in goats that originated from six districts in communal grazing semi-arid areas of Zambia. A total of 181 samples (40.1%) out of 451 serum samples from adult goats were positive for Ehrlichia ruminantium antibodies after screening using indirect MAP-1B antigen ELISA technique with statistically significant differences (P < 0.01) between the six districts. Out of 1 036 adult goats examined for tick infestation, 105 were infested by ticks, with Amblyomma species being the most dominant tick encountered. Amblyomma variegatum, which is the vector for heartwater transmission in Zambia constituted 42.4% of the tick species, identified. The overall tick infestation rate was 10% while the tick:goat ratio was 2.1:1. Amblyomma variegatum appears to be widespread throughout the study area, as are antibodies to E. ruminantium.     

Epidemiology of Oestrus ovis (Linneo, 1761) infestation in goats in Spain

This survey was conducted to determine the chronobiology and seroprevalence of nasal bot infestation (Oestrus ovis) in Spain and to identify the risk factors associated with this disease in caprine herds.

A total of 1590 sera from adult goats were collected at random on 175 farms in southwestern Spain. Sera were tested by ELISA, using crude protein from second stage larvae as antigen. The mean seroprevalence was 46.04% and mean percentage of optical densities was 41.83. These data indicate a high prevalence of this parasite in the investigated areas. The serological survey revealed that goats managed at higher altitudes, at meridians latitudes and on farms with small herds had a smaller probability of infestation. Eighty goat heads, obtained from abattoirs in the central region of Spain, were collected and examined for nasal botflies from February to October 2002. O. ovis larval stages were recovered from the nasal-sinus cavities of 23 goats, reaching a prevalence of 34.94%. The mean larval burden was 3.9 larvae per infested head. No first instars were found during February and March, when the second instar reached its larger count. The third instar was observed in very small number during the whole period of study, with one peak occurring in July–August. These data show the existence of a favourable period for the development of larval instars of O. ovis in goats that starts in February and finishes in September.     

Incidence of Oestrus ovis infestation in Borno-white Sahel goats in the semi-arid zone of Nigeria

Research conducted on the incidence of Oestrus ovis in Maiduguri showed that 53.8% of the 4,000 Borno-White Sahel goats examined were parasitised. The mean year-round infestation per goat was 2.03 larvae. Adult goats had a higher infestation rate than younger ones (60 versus 47.5%). Infestation rates for the females and males were 55.2 and 52.2%, respectively. Nevertheless there was no statistical significance between values for the different age and sex groups studied. Different larval stages were encountered throughout the year with a 3rd instar peak between May and September and a first instar peak from June to October suggesting a fly period between June and October.     

Effect of Ctenocephalides felis strongylus infestation on the performance of West African dwarf sheep and goats

Summary

A study of Ctenocephalides fells strongylus and of its effect on the performance of sheep and goats was made.

Fleas showed more affinity for sheep than goats. There was a high concentration between lamb and kid mortality and the degree of flea infestation. The clinical effects of flea infestation are highlighted. The factors responsible for flea infestation and its control are discussed.     

Biological, seasonal and environmental factors associated with Pulex irritans infestation of dairy goats in Greece

The objectives of the present study were to study the fauna of fleas infesting dairy goats in Greece, the spectrum of hosts each flea species infests, identify risk factors in the environment, and goat management practices that favour flea infestation of goats, and describe the seasonal variation of infestation in goats. For this purpose, a total of 64 herds, with a history of flea infestation in goats, were visited during June and July of 2002 for data collection on flea burdens, species of fleas on goats, and other farm or pet animal species in the farm. Also data were collected on herd characteristics and management along with the flea infestation status of the village where it was located through a questionnaire survey. Data on elevation and climatic characteristics of the villages where the herds were located were also used in the study. All fleas collected from goats, sheep, pigs, and cattle were identified as being Pulex irritans. All fleas collected from cats were identified as being Ctenocephalides felis. Dogs were infested either with P. irritans, C. canis, or C. felis, or with both C. canis and C. felis. Kids had a significantly higher flea burden than goats and the Skopelos breed had the highest flea burden of all breeds followed in diminishing order by the breeds Capra prisca, Saanen cross mix, and Alpine cross mix (p < 0.05). The gender of the animal had no significant effect on flea burden. Factors significantly affecting the flea burden of goats were duration of flea infestation in the herd, type of flea control, and manure imported prior to the appearance of fleas in the herd (p < 0.05). The flea burden of goats was highest during summer and lowest during winter (p < 0.01), with complete an absence of infestation in January and February. Finally, a significant difference (p < 0.05) was found between the average annual temperature of villages with flea infestation (15.59 degrees C) and villages without flea infestation (17.14 degrees C). It was concluded that P. irritans was a true infestation of goats in Greece.     

Seasonal occurrence of Karoo paralysis in Angora goats in relation to the infestation density of female Ixodes rubicundus.

The seasonal occurrence of Karoo paralysis in relation to the infestation density of female Ixodes rubicundus was investigated in an enzootic area of the southwestern Orange Free State, South Africa. Young and adult Angora goats were exposed to infestation during two paralysis tick seasons. Only the young goats became paralysed and their infestation densities (female ticks kg-1 host body weight) were significantly higher than those of healthy animals. The infestation densities on paralysed goats varied between 0.64 and 3.56 ticks kg-1. During the 1988 season, 30% of the naive young goats became paralysed compared with 67% the following season. Twenty-nine percent of previously paralysed goats were paralysed again during the same season. Paralysis occurred during periods of peak tick activity (April-June).     

Cross-transmission studies with Hypoderma lineatum de Vill. (Diptera: Oestridae): attempted infestation of goats (Capra hircus)

The potential for cross-transmission of Hypoderma lineatum from cattle to domestic goats (Capra hircus) was examined using artificial infestation techniques. Two routes of infestation, subcutaneous injection and dermal penetration, were used to expose goats to newly hatched first instars. Presence of antibodies and appearance of circulating antigen (hypodermin C) were evaluated at selected intervals for up to 40 weeks post-infestation. In addition, immunoblots against H. lineatum first-instar proteins were conducted using sera taken at 10 weeks post-infestation. Goats were palpated for the presence of developing larvae at sub-dermal sites beginning at week 30 pi. No developing larvae were palpated at any time, regardless of the route of infestation nor was circulating antigen detected in any infested goats. Antibodies were present at weeks 6 and 10 and week 27 pi in both infested groups. Immunoblots indicated all infested goats produced antibodies to first instar H. lineatum antigens. H. lineatum appears to be incapable of completing development in domestic goats although the transient appearance of ELISA detectable antibodies and the presence of bands on immunoblots suggests that at least some larvae survive long-enough to engender a humoural response. The host specificity of H. lineatum is discussed in light of the general concepts of host-parasite relationships of oestrids.     

Economic impact of <Emphasis Type="Italic">Przhevalskiana silenus</Emphasis> infestation in native goats of Northern India

Economic losses incurred by Przhevalskiana silenus in goats of Jammu province of Jammu and Kashmir (North India) were assessed from July 2005 to June 2006. Abattoir studies revealed holes in hides for 112 days (mid-December 2005 to first week of April 2006) and trimming of carcass for 243 days (July 2005 to February 2006) during a lifecycle, leading to annual losses of Rs. 7,391,432 and Rs. 10,510,837, respectively. An effect on production traits (weight gain and milk) was assessed on naturally P. silenus-infested Beetal goats. The mean body weight loss of warbled goats was 2.40 kg (equal to 1.096 kg of meat, assuming 45.7% dressing percentage of goat) leading to an annual loss of Rs. 35,473,265. The mean milk yield loss per warbled goat per day was 101.7 g resulting in losses to the tune of Rs. 19,879,012. It can be concluded that P. silenus infestation resulted in an overall loss of Rs. 73,254,547, i.e. 73.26 million annually (equivalent to US 1.62 million; US1.62 million; US 1 = Rs. 45.24), where reduced growth alone contributed 49% of the total losses. A study recommends that a control scheme against P. silenus infestation in goats using an effective insecticide should be followed to prevent huge economic losses in hide, milk and meat production. Economic losses associated with P. silenus infestation in goats were estimated for the first time from India.     

A primary animal health care approach to treatment and control of flea (Ctenocephalides felis) infestation in indigenous goats kept on communal grazing

This paper describes a primary health care approach to an infestation of indigenous goats by the common cat flea, Ctenocephalides felis. The flea species was identified using scanning electron microscopy. The infested goats were kept on communal grazing at Winterveld in the North-West Province. They were penned at night in housing made of wire and corrugated iron. The owner complained that the goats were lethargic. Fleas were found on the goats and flea larvae were found in the kraal. Haematology and blood biochemistry performed on the infested goats revealed no abnormalities; however, infestation caused irritation that made the animals lethargic. Available flea control methods for domestic animals were appraised in terms of cost, availability and ease of administration at a primary animal health care level using participatory extension methods. It was found that a carbamate powder was available, affordable and effective for flea control in this small flock of goats kept under communal grazing conditions. Although the authors had observed fleas on goats kept under similar conditions elsewhere in Mpumalanga and the North-West Province, this was the 1st time that the species had been identified.     

Worm infestation after phenothiazine

Extract

Your readers may be interested in the rather unexpected results of a trial I carried out earlier this year.