Amphistome infection of goats farmed under resource-poor conditions in South Africa

From December 1998 to April 2000, a longitudinal study was conducted of the pooled trematode faecal egg counts of samples collected from goats of resource-poor farmers at Rust de Winter, Gauteng Province, Impendle, KwaZulu-Natal Province, and Kraaipan, North-West Province, South Africa. The amphistome faecal egg counts followed a seasonal pattern, with an increase in the counts during the warmer months of the year (October to March). This is the first work concerning the seasonal cycling of amphistomes in ruminants in South Africa.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat v.9 was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.Food and Agriculture Organization of the United Nations Technical Co-operation Project TCP/SAF/8821.mn201

The potential to control Haemonchus contortus in indigenous South African goats with copper oxide wire particles

The high prevalence of resistance of Haemonchus contortus to all major anthelmintic groups has prompted investigations into alternative control methods in South Africa, including the use of copper oxide wire particle (COWP) boluses. To assess the efficacy of COWP against H. contortus in indigenous South African goats, 18 male faecal egg-count-negative goats were each given ca.1200 infective larvae of H. contortus three times per week during weeks 1 and 2 of the experiment. These animals made up an “established” infection group (ESTGRP). At the start of week 7, six goats were each given a 2-g COWP bolus orally; six goats received a 4-g COWP bolus each and six animals were not treated. A further 20 goats constituted a “developing” infection group (DEVGRP). At the beginning of week 1, seven of the DEVGRP goats were given a 2-g COWP bolus each; seven goats were treated with a 4-g COWP bolus each and no bolus was given to a further six animals. During weeks 1–6, each of these DEVGRP goats was given ca. 400 H. contortus larvae three times per week. All 38 goats were euthanized for worm recovery from the abomasa and small intestines in week 11. In the ESTGRP, the 2-g and 4-g COWP boluses reduced the worm burdens by 95% and 93%, respectively compared to controls (mean burden ± standard deviation, SD: 23 ± 33, 30 ± 56 and 442 ± 518 worms, P = 0.02). However, in the DEVGRP goats, both the 2-g and 4-g COWP treatments were ineffective in reducing the worm burdens relative to the controls (mean burdens ± SD: 1102 ± 841, 649 ± 855, 1051 ± 661 worms, P = 0.16). Mean liver copper levels did not differ between the ESTGRP goats treated with 2-g COWP, 4-g COWP or no COWP (mean ± standard error of the mean, SEM, in ppm: 93.7 ± 8.3; 101.5 ± 8.3; 71.8 ± 8.3, P = 0.07) nor did they differ between the DEVGRP goats (mean ± SEM, in ppm: 74.1 ± 9.1; 75.4 ± 9.1; 74.9 ± 10.0, P > 0.99). The copper values were considered adequate, but not high, for goats. The COWP boluses have the potential to be used in the place of conventional anthelmintics for the control of established H. contortus infections in indigenous South African goats, but their use as part of an integrated approach to control H. contortus in the field must be fully investigated

Persistence of the efficacy of copper oxide wire particles against Haemonchus contortus in grazing South African goats

A study was conducted to examine the duration of anthelmintic effect of copper oxide wire particles (COWP) in grazing goats, as data for the persistence of efficacy of COWP in this host species is limited. Forty-eight indigenous male goats were infected naturally by grazing them on Haemonchus contortus-infected pasture. When the faecal egg count (FEC) in the goats was 3179 ± 540 eggs per gram of faeces (mean ± standard error), half the animals were treated with 4 g COWP (day 0; mean live weight = 25.5 ± 0.8 kg). Eight treated (COWP) and eight non-treated (CONTROL) goats were removed from the pasture on each of days 7, 28 and 56, maintained for 27 or 29 days in concrete pens and then humanely slaughtered for nematode recovery. Mean liver copper levels were in the high range in the goats removed from pasture at day 7 (treated: 191 ± 19.7 ppm; untreated: 120 ± 19.7 ppm; P = 0.022), but had dropped to normal levels at days 28 and 56. The mean H. contortus burdens of the treated versus the non-treated goats were, respectively, 184 ± 48 and 645 ± 152 for the goats removed from pasture at day 7 (71% reduction; P = 0.004), 207 ± 42 and 331 ± 156 at day 28 (37% reduction; P = 0.945) and 336 ± 89 and 225 ± 53 at day 56 (−49% reduction; P = 0.665). Weekly monitoring of FECs after treatment until slaughter indicated that the COWP-treated goats had lower FECs than the controls, the treatment main effect being significant at days 7, 28 and 56 (P < 0.01). The day main effect and the treatment × day interaction were only significant for the goats removed from pasture at day 28 (P ≤ 0.001). Packed cell volumes increased during the course of the experiment (day, P < 0.001), but the treatment main effect was significant only for the goats removed from pasture at day 28 (CONTROL 28 d, 28.65 ± 0.52% < COWP 28 d, 31.31 ± 0.52%; P < 0.001). No differences in live weight between groups were considered to be of any practical significance. The study indicated that persistence of efficacy of COWP is limited in goats, extending at most to 28 days after treatment. However, repeated COWP administration at three-month intervals may be safe, given that liver copper levels return to normal two to three months after COWP treatment

Direct anthelmintic effects of Cereus jamacaru (Cactaceae) on trichostrongylid nematodes of sheep : in vivo studies

Following claims of anthelmintic activity of Cereus jamacaru DC (Cactaceae) by a commercial farmer, in vivo studies were conducted to determine the possible direct anthelmintic effects of the plant on ovine gastrointestinal nematodes. Eighteen sheep were infected with 4000 Haemonchus contortus and 6000 Trichostrongylus colubriformis larvae given in three divided doses over a period of three days. Once the infections were patent, the sheep were allocated to three groups and were drenched once a week for six weeks with fresh blended C. jamacaru plant material at a single (32.3 g/sheep) or double dose (64.6 g/sheep) or they remained as undrenched controls. Faeces were collected from individual animals on the day of treatment and three days thereafter on a weekly basis for seven weeks for faecal egg count. While there were no statistically significant differences in the egg counts between the groups, a double dose of C. jamacaru was effective in reducing the egg counts in the sheep by 18-65% over the 49 days of the experiment. Given that all animals remained in good health throughout the course of the experiment, with no adverse events occurring during the study, further experiments using higher doses or administering the plant material for a longer period of time than in the present study would be warranted.The National Research Foundation of South Africa (NRF), the Phytomedicine Programme of the Faculty of Veterinary Science, University of Pretoria and the Onderstepoort Veterinary Institute (OVI) provided financial support.http://www.elsevier.com/locate/vetpa

Tactical treatment with copper oxide wire particles and symptomatic levamisole treatment using the FAMACHA © system in indigenous goats in South Africa

Haemonchosis is considered to be the most economically important gastrointestinal disease of small ruminants in the tropics and subtropics. However, chemical anthelmintics, which were the mainstay of control, have been compromised by a high prevalence of resistance worldwide. Copper oxide wire particles (COWP) have been shown to have anthelmintic effects, but few studies have examined their use under field conditions. The use of COWP was therefore evaluated as a tactical anthelmintic treatment in indigenous goats raised under communal farming conditions in Bergville, KwaZulu-Natal Province, South Africa. At the beginning of the summer rainfall season (October 2007), the faecal egg counts of 172 female goats belonging to 15 farmers were determined and this sampling continued every four weeks until the second week of January 2008. The goats within each of the 15 herds were ranked according to their faecal egg counts for this week. The goats were sequentially paired off within each ranking starting with those goats with the highest counts. One goat from each pair was randomly allocated to a treated or control group. Two weeks later, a 4 g COWP bolus was randomly administered to each goat in the treated group. Faecal egg counts were carried out on the goats two weeks following treatment, and the sampling of the goats then proceeded every four weeks until October 2008. Except for the six-week period prior to the administration of the COWP, the goats were examined according to the FAMACHA© system and symptomatically treated with 12 mg/kg levamisole when anaemic. The percentage reduction in faecal egg count due to the COWP treatment was 89.0%. Mean pre- and post-treatment faecal egg counts for the COWP-treated group (n = 73) were 2347 eggs per gram of faeces (epg) and 264 epg, respectively. The corresponding values for the untreated controls (n = 66) were 2652 epg and 2709 epg. The prevalence of Haemonchus spp. larvae in pre- and post-treatment faecal cultures was 72% and 46%, respectively. Symptomatic anthelmintic treatments in combination with mid-summer tactical treatments with COWP appear to be useful strategies for the control of Haemonchus contortus in indigenous goats in this farming system and this approach could have application in other similar agro-ecological zones.This project was funded by The Wellcome Trust project number 075812/A/04/7, Onderstepoort Veterinary Institute (OVI), South Africa and KwaZulu-Natal Department of Agriculture, Environmental Affairs and Rural Development (KZN DoAEA&RD), South Africa.www.elsevier.com/locate/vetparhb2013ab201

Managing anthelmintic resistance in small ruminant livestock of resource-poor farmers in South Africa : review article

Gastrointestinal parasitism is one of the most important disease complexes of sheep and goats impacting on the resource-poor livestock farmer. Of the responsible nematodes, Haemonchus contortus, a blood-sucking worm of the abomasum, poses possibly the greatest threat. Over the past several decades, the worm has been controlled through the use of anthelmintics, but the emergence of anthelmintic resistance has threatened this chemotherapeutic approach. In Africa, the overall prevalence of anthelmintic resistance has not been extensively investigated, particularly within the resource-poor farming sector, but resistance has been reported from at least 14 countries with most of the reports emanating from Kenya and South Africa and the majority concerning H. contortus. While levels of resistance under commercial sheep farming systems in South Africa is considered to be amongst the worst in the world, resistance has also been reported from the resource-poor farming sector. Increases in productivity and reproduction of livestock and the development of markets for sale of animals are seen by international funding bodies as a way out of poverty for communities that keep livestock. This must lead to the greater need for parasite control. At such times, the risk of levels of anthelmintic resistance escalating is much greater and there is therefore a need to look at alternatives to their use. Proposed strategies include the appropriate, but judicious use of anthelmintics by application of the FAMACHA(c) system and the use of alternatives to anthelmintics such as strategic nutrient supplementation. It is also very clear that there is a strong demand for knowledge about animal diseases, including helminthosis, and their effective management in the resource-poor livestock farming communities. This is an important challenge to meet

Managing anthelmintic resistance in small ruminant livestock of resource-poor farmers in South Africa : review article

Gastrointestinal parasitism is one of the most important disease complexes of sheep and goats impacting on the resource-poor livestock farmer. Of the responsible nematodes, Haemonchus contortus, a blood-sucking worm of the abomasum, poses possibly the greatest threat. Over the past several decades, the worm has been controlled through the use of anthelmintics, but the emergence of anthelmintic resistance has threatened this chemotherapeutic approach. In Africa, the overall prevalence of anthelmintic resistance has not been extensively investigated, particularly within the resource-poor farming sector, but resistance has been reported from at least 14 countries with most of the reports emanating from Kenya and South Africa and the majority concerning H. contortus. While levels of resistance under commercial sheep farming systems in South Africa is considered to be amongst the worst in the world, resistance has also been reported from the resource-poor farming sector. Increases in productivity and reproduction of livestock and the development of markets for sale of animals are seen by international funding bodies as a way out of poverty for communities that keep livestock. This must lead to the greater need for parasite control. At such times, the risk of levels of anthelmintic resistance escalating is much greater and there is therefore a need to look at alternatives to their use. Proposed strategies include the appropriate, but judicious use of anthelmintics by application of the FAMACHA(c) system and the use of alternatives to anthelmintics such as strategic nutrient supplementation. It is also very clear that there is a strong demand for knowledge about animal diseases, including helminthosis, and their effective management in the resource-poor livestock farming communities. This is an important challenge to meet

Workshop discusses priorities in veterinary helminthology for South Africa : information

A workshop was held at Onderstepoort to set priorities in veterinary helminthology for South Africa. Representatives from 19 organisations attended. The workshop achieved 2 of the 3 aims set, namely to identify the problems within the field and to develop strategies to address these challenges. The 7 strategies proposed are: motivation, education, therapeutic, worm resistance, animal tolerance, biological control and diagnostic strategies. A follow-up session is being planned to formulate action plans for each sphere

Tactical treatment with copper oxide wire particles and symptomatic levamisole treatment using the FAMACHA© system in indigenous goats in South Africa

Haemonchosis is considered to be the most economically important gastrointestinal disease of small ruminants in the tropics and subtropics. However, chemical anthelmintics, which were the mainstay of control, have been compromised by a high prevalence of resistance worldwide. Copper oxide wire particles (COWP) have been shown to have anthelmintic effects, but few studies have examined their use under field conditions. The use of COWP was therefore evaluated as a tactical anthelmintic treatment in indigenous goats raised under communal farming conditions in Bergville, KwaZulu-Natal Province, South Africa. At the beginning of the summer rainfall season (October 2007), the faecal egg counts of 172 female goats belonging to 15 farmers were determined and this sampling continued every four weeks until the second week of January 2008. The goats within each of the 15 herds were ranked according to their faecal egg counts for this week. The goats were sequentially paired off within each ranking starting with those goats with the highest counts. One goat from each pair was randomly allocated to a treated or control group. Two weeks later, a 4 g COWP bolus was randomly administered to each goat in the treated group. Faecal egg counts were carried out on the goats two weeks following treatment, and the sampling of the goats then proceeded every four weeks until October 2008. Except for the six-week period prior to the administration of the COWP, the goats were examined according to the FAMACHA© system and symptomatically treated with 12 mg/kg levamisole when anaemic. The percentage reduction in faecal egg count due to the COWP treatment was 89.0%. Mean pre- and post-treatment faecal egg counts for the COWP-treated group (n = 73) were 2347 eggs per gram of faeces (epg) and 264 epg, respectively. The corresponding values for the untreated controls (n = 66) were 2652 epg and 2709 epg. The prevalence of Haemonchus spp. larvae in pre- and post-treatment faecal cultures was 72% and 46%, respectively. Symptomatic anthelmintic treatments in combination with mid-summer tactical treatments with COWP appear to be useful strategies for the control of Haemonchus contortus in indigenous goats in this farming system and this approach could have application in other similar agro-ecological zones