Survey for drug-resistant gastrointestinal nematodes in 13 commercial sheep flocks.

The prevalence of drug-resistant ovine parasites in the United States has not been widely reported. Thirteen flocks, typical of commercial sheep production units, were selected for survey. Four anthelmintics (fenbendazole, ivermectin, pyrantel pamoate, and levamisole) were tested for their ability to reduce herd mean pretreatment fecal egg count. If a properly dosed and administered drug failed to reduce herd mean pretreatment fecal egg count by 80%, it was considered ineffective in that flock, and the presence of parasites resistant to that drug was inferred. Fenbendazole administration changed pretreatment fecal egg counts by +9% to -100%. On the basis of the aforementioned definition, drug resistance existed in 6 of 13 flocks. Posttreatment larval culture indicated that Haemonchus contortus survived administration of fenbendazole. Levamisole, pyrantel pamoate, and ivermectin reduced pretreatment fecal egg count by -83% to -100%; resistance to these products was not evident in the flocks surveyed.     

Anthelmintic resistance in sheep and goat farms on Peninsular Malaysia.

The faecal egg count reduction test (FECRT) was conducted on 39 sheep farms and 9 goat farms located in Peninsular Malaysia. The anthelmintic groups used in these tests were the benzimidazoles, levamisole, the benzimidazole/levamisole combination, macrocyclic lactones and closantel. Results indicated that the prevalence of resistance to the benzimidazole group was high, with approximately 50% of the sheep farms and 75% of the goat farms having resistant nematode parasite populations present. Resistance to levamisole, closantel and ivermectin was also detected. Differentiation of the infective larvae derived from faecal cultures indicated that by far the most predominant parasite species was Haemonchus contortus.     

Management and control of gastrointestinal nematodes in communal goat farms in Zimbabwe

Goats are an important source of livelihood especially in smallholder communities. Infections with gastrointestinal nematodes (GIN) remain the most prevalent parasitic diseases affecting small ruminants. The study was conducted to assess management, the level of knowledge and control of gastrointestinal nematodes. Surveys were conducted in Chipinge, Shurugwi, Binga, Tsholotsho and Matobo districts, representing the five natural/agro-ecological regions (NR) in Zimbabwe. Data was collected in 135 households using a pre-tested semi-structured questionnaire. Results indicated that goats were ranked the most important livestock species, with high flock sizes in NR IV and V. Partitioning of roles was such that the adult males were involved in decision-making while females and children were involved in day-to-day management of animals. Farmers showed low levels of input use, with natural pasture (98.4%) being the main feed source and indigenous breeds (73.2%) being kept. Farmers ranked food and financial benefits as the main reasons for keeping goats. Gastrointestinal nematodes ranked the highest as the most common disease, with majority of farmers (57%) not controlling or treating animals and 63% of farmers not having knowledge on the spread of GIN. Access to veterinary services, anthelmintic class used and breeds used by the farmers had the highest effects on parasitic infections in households. Farmer education is required for capacitation of farmer in terms of disease prevention and control so as to improve goat production.     

Anthelmintic resistance on goat farms in Georgia: efficacy of anthelmintics against gastrointestinal nematodes in two selected goat herds

Gastrointestinal nematode (GIN) parasitism is a major constraint to production of goats in the southeastern United States. The conventional method of control used by producers in this region is frequent use of anthelmintics during the warm season. Overuse of anthelmintics has led to an increase in the incidence of anthelmintic resistance in many parts of the world, but data on prevalence of anthelmintic resistance in GIN of goats in the southeastern United States are very limited. To address this issue, anthelmintic efficacy was determined in goat herds at the Fort Valley State University, Agricultural Research Station (FVSU-ARS) and the University of Georgia, College of Veterinary Medicine (UGA-CVM) using fecal egg count reduction (FECR) tests and DrenchRite((R)) larval development assays (LDA). At FVSU-ARS, 2-year-old Spanish goat does were randomly allocated to one of nine different treatment groups (n = 10): albendazole (ABZ; 20mg/kg body weight (BW)), fenbendazole (FBZ; 20mg/kg BW), ivermectin (IVM; 0.4 mg/kg BW), doramectin (DRM; 0.4 mg/kg BW), moxidectin (MOX; 0.4 mg/kg BW), levamisole (LEV; 12 mg/kg BW), morantel tartrate (MOR; 10mg/kg BW), a combination of IVM (0.4 mg/kg BW) and ABZ (20 mg/kg BW), and untreated controls. At UGA-CVM, goats were randomly allocated to one of five different treatment groups (n = 8): ABZ (20 mg/kg BW), IVM (0.4 mg/kg BW), MOX (0.4 mg/kg BW), LEV (12 mg/kg BW), and untreated controls. All drugs in both experiments were administered orally. Anthelmintic efficacy was calculated by comparing 14-day post-treatment FEC of treated and control animals, and percent reductions were interpreted using the World Association for the Advancement of Veterinary Parasitology guidelines for resistance. For the LDA, nematode eggs were isolated from pooled fecal samples of untreated control goats in each herd and used to perform DrenchRite((R)) assays. In the FVSU-ARS herd, MOX, LEV, the combination of IVM and ABZ, IVM, DRM, ABZ, MOR, and FBZ reduced FEC by 100, 91, 88, 78, 76, 62, 48, and 10%, respectively. In the UGA-CVM herd, MOX, LEV, ABZ and IVM, reduced FEC by 100, 94, 87, and 0%, respectively. In both herds moxidectin was the only drug tested that was fully effective. Results of the LDA were in agreement with results of the FECR tests for both herds. These data demonstrate the presence of GINs resistant to all three major anthelmintic classes in both goat herds.     

A survey of anthelmintic resistance on ten goat farms in the Manawatu region in 1988

A survey of anthelmintic resistance on ten goat farms was carried out. The criterion for resistance was a faecal egg count reduction (FECR) of <90 percent based on arithmetic means of 11 to 19 goats per group. It was found that nine of the ten farms harboured nematodes resistant to oxfendazole when used at 5mg/kg although on two of these, the FECR's were 89.2 percent and 89.8 percent. Post treatment larval cultures indicated Haemonchus, Ostertagia and Trichostrongylus were the resistant genera involved. On none of the ten farms was resistance to oral ivermectin at 0.2mg/kg detected.     

A survey of anthelmintic resistance on ten goat farms in the Manawatu region in 1988

A survey of anthelmintic resistance on ten goat farms was carried out. The criterion for resistance was a faecal egg coynt reduction (FECR) of <90 percent based on arithmetic means of 11 to 19 goats per group. It was found that nine of the ten farms harboured nematodes resistant to oxfendazole when used at Smg/kg although on two of these, the FECR's were 89.2 percent and 89.8 percent. Post treatment larval cultures indicated Haemonchus, Ostertagia and Trichostrongylus were the resistant genera involved. On none of the ten farms was resistance to oral ivermectin at 0.2mg/kg detected.     

On-farm welfare assessment of dairy goat farms using animal-based indicators: the example of 30 commercial farms in Portugal

Welfare assessment can play multiple roles in the path to welfare improvement. In the dairy goat area, identification of the main welfare problems across countries and different production systems is needed. By the application of a prototype welfare assessment protocol, based on animal-based indicators, we aimed to provide an insight into the main welfare problems affecting intensively kept dairy goats in Portugal. Thirty farms, organised in three size categories, were assessed. The main areas of concern were claw overgrowth, queuing at feeding and hindquarter dirtiness, with larger farms heading higher concerns. Additionally, this paper aimed to investigate indicators’ consistency over time. Ten of the 30 farms were revisited four months later, during which no major husbandry changes were made. Our results showed an overall consistency. This study can help define intervention thresholds or minimum legal levels for each indicator, by determining their overall prevalence.     

Assessment of welfare on 24 commercial UK dairy goat farms based on direct observations

The preliminary findings from an investigation into the health and welfare of goats on commercial dairy goat farms in the UK are described. An assessment protocol involving direct observations of the goats was developed in order to assess their welfare. Twenty-four dairy goat farms in England and Wales were visited and assessed during the period autumn 2004 to summer 2005. The main welfare issues identified were lameness and claw overgrowth, udder and teat lesions, skin lesions and pruritus.     

Assessment of gastrointestinal nematode infection,anthelmintic usage and husbandry practices on two small-scale goat farms in Malaysia

Haemonchosis is a common problem on goat farms in tropical countries such as Malaysia. Prevention of production losses generally depends on the use of anthelmintic drugs, but is threatened by the emergence of anthelmintic resistance. This study investigates anthelmintic efficacy on small-scale Malaysian goat farms and describes putative risk factors. Adult goats had moderate to high pre-treatment faecal trichostrongyle egg counts, despite being housed on slatted floors and fed on cut-and-carry forage, raising questions about the source of nematode infection. Our results show multiple resistance to benzimidazole and macrocyclic lactone anthelmintic drugs and allow us to discuss the genetic origins of resistance with reference to farm husbandry and management. We conclude that improvement in Malaysian goat production efficiency will require the development of sustainable helminth control strategies, underpinned by a better understanding of the origins and population genetics of anthelmintic resistance.     

Prevalence and molecular identification of Chlamydia abortus in commercial dairy goat farms in a hot region in Mexico

The aim of this study was to determine the seroprevalence and presence of Chlamydia abortus in Saanen breed female goats from commercial dairy goat farms under intensive production in the municipality of Guanajuato, Mexico. Sera were collected to determine the prevalence of anti-C. abortus IgG antibodies using recombinant enzyme-linked immunosorbent assay (rELISA) and cell culture. Polymerase chain reaction (PCR) was used to prove the presence of the pathogen in swab samples collected from the vagina and rectum of selected animals. Additionally, foetal tissue samples from a sudden abortion were collected. C. abortus prevalence in female goats of commercial milking farms sampled in Guanajuato, Mexico, was 4.87 % (n?=?246). Seropositive animals were found in six out of nine (66.6 %) dairy goat farms sampled, and prevalence among animals in individual farms ranged between 3.44 and 13.51 %. C. abortus was detected using PCR in spleen tissue from the aborted foetus. PCR-based detection, as well as isolation from vaginal and rectal swabs, was not possible in the present study. Isolation through cell culture was also unsuccessful from aborted foetal tissue samples. In conclusion, the results from rELISA and PCR show that C. abortus is present in dairy goat farms in the state of Guanajuato, Mexico.     

Disease in 27 Norwegian dairy goat farms

A combination of field registrations and laboratory examinations was used to describe the distribution, morbidity and mortality of disease among dairy goats in the western part of Norway.     

Survey of the prevalence of Salmonella species on commercial laying farms in the United Kingdom

A survey of salmonella infection on 454 commercial layer flock holdings in the uk was carried out between October 2004 and September 2005. Fifty-four (11.7 per cent, 95 per cent confidence interval 9.3 to 14.0 per cent) were salmonella positive. The most common serovar identified was Salmonella Enteritidis at a prevalence of 5.8 per cent, and 70 per cent of these isolates were phage types 4, 6, 7 and 35. Salmonella Typhimurium was the second most prevalent serovar, found in 1.8 per cent of the farms. Of the three other serovars given top priority by the eu because of their public health significance, Salmonella Virchow and Salmonella Infantis were each isolated from one holding, but Salmonella Hadar was not isolated from any of the holdings. Analysis of antimicrobial resistance patterns revealed that over 76 per cent of the isolates were sensitive to all of the 16 drugs tested, and all the isolates were sensitive to ciprofloxacin, gentamicin, ceftazidime, apramycin, amikacin, amoxicillin/clavulanic acid, neomycin and cefotaxime.     

Mycoplasma ovis infection in goat farms from northeastern Brazil

Although Mycoplasma ovis (formerly Eperythrozoon ovis) has been described in small ruminants worldwide, data on M. ovis in goats remain scarce. Accordingly, the aims of the present study were to i) determine the prevalence of hemoplasmas in goats, ii) identify the tick species parasitizing the animals, and iii) determine factors associated with infection in five dairy and three beef goat farms from the Paraíba State, northeastern Brazil. Blood samples were obtained from 402 goats. Samples were screened for hemoplasmas using a pan-hemoplasma PCR. The positive samples were confirmed by sequencing. An epidemiological questionnaire was given to each farm owner addressing age, gender, and presence of ticks. A total of 158/402 (39.3%) goats were positive for M. ovis by PCR. Sequencing of PCR positive samples has shown ≥99% identity with multiple M. ovis 16S rDNA sequences deposited in GenBank, including M. ovis isolates from humans. Dairy (OR = 2.15; 95% CI: 1.40–3.32%; P = 0.0004) and anemic goats (OR = 2.33; 95% CI: 1.51–3.71%; P = 0.0001) were more likely to be infected than beef and non-anemic animals, respectively. Amblyomma parvum (49/52, 94.23%) and Rhipicephalus microplus (3/52, 5.77%) were the tick species found parasitizing the animals, with no significant association between the presence of ticks and infection by M. ovis (P = 0.1164). This is the first reportedly molecular detection of M. ovis infection in goats from South America. In conclusion, M. ovis is highly prevalent in goats from northeastern Brazil, mainly in dairy animals.     

Possible application of a nematophagous fungus as a biological control agent of parasitic nematodes on commercial sheep farms in South Africa

Biological control of parasitic nematodes of livestock is currently under development and represents another tool that may be integrated into helminth parasite control strategies. This paper presents a brief introduction to commercial sheep farming in South Africa and currently available nematode parasite control methods. These include the FAMACHA clinical assay, strategies of pasture management, dilution of resistant worm species by introduction of susceptible worms, breed resistant sheep and nutritional supplementation. The purpose of this paper is to outline the principles of biological control using nematophagous fungi and how it may be applied on sheep farms in South Africa.     

Strategies of newcastle disease vaccination for commercial ostrich farms in Japan

Strategies of Newcastle disease (ND) vaccination were demonstrated in a commercial ostrich farm in Japan. Three of 13 seven-month-old ostriches kept in a pen were vaccinated with a live ND vaccine by eye dropping for the 1st and 2nd vaccinations and spraying for the 3rd to 5th vaccinations. Antibodies against ND virus (NDV) were detected in all of the unvaccinated ostriches by virus neutralization test. At 2.5 months post final vaccination, 2 ostriches introduced into the pen raised antibodies against NDV. These data indicate that NDV may be transmitted from vaccinated to unvaccinated ostriches in the flock and that the virus may be sustained for a certain period in the flock. These data may be helpful for ND vaccination management in ostrich farms.     

Survey of Salmonella prevalence on commercial turkey breeding and fattening farms in the UK in 2006 to 2007

A total of 29 breeding turkey holdings and 317 fattening turkey holdings were sampled between October 2006 and September 2007 in order to establish the baseline prevalence of Salmonella in turkeys in the UK. The weighted holding level Salmonella prevalence was found to be 20.1 per cent (95 per cent confidence interval [CI] 8.6 to 40.3 per cent) in breeding turkeys and 37.7 per cent (95 per cent CI 33.4 to 42.3 per cent) in fattening turkeys. For breeding turkeys, a weighted flock-level prevalence, as more than one flock per holding was sampled, was estimated at 7.1 per cent (95 per cent CI 3.2 to 14.8 per cent). A total of 13 different serovars were identified in the survey. The most frequent serovar in both turkey flock classes was Salmonella Kottbus, which was found on two breeding holdings and 63 of the fattening holdings giving weighted prevalences of 10.4 per cent (95 per cent CI 2.6 to 34.1 per cent) and 23.0 per cent (95 per cent CI 19.3 to 27.3 per cent), respectively. On breeding holdings, a single isolate of Salmonella Typhimurium, identified as DT12 (weighted prevalence 3.5 per cent [95 per cent CI 0.7 to 15.8 per cent] [holding], 0.7 per cent [95 per cent CI 0.1 to 3.7 per cent] [flock)], was found. On fattening holdings, there were 55 isolates of S Typhimurium from 16 holdings, giving a weighted prevalence of this serovar of 5.4 per cent (95 per cent CI 3.6 to 8.0 per cent). There were no isolates of Salmonella serovars Enteritidis, Hadar, Infantis or Virchow.     

Prevalence of fenbendazole resistance in ovine nematodes in north west india

Summary A survey was undertaken between March and September 1992 to assess the prevalence of fenbendazole resistance in sheep nematodes in 32 traditionally managed rural flocks and 22 intensively managed flocks on 3 farms. Fenbendazole, a commonly used anthelmintic was used at the recommended dose of 5 mg/kg body weight. Efficacy was determined on the basis of percentage reduction in strongyle faecal egg counts (FECR%) and larval cultures before and between 7 and 10 days after treatment. None of the traditionally managed rural flocks showed resistance and all had greater than 99% reduction in faecal egg counts after treatment.Of the 22 intensively managed flocks, however, 15 had slight fenbendazole resistance (between 60 and 90% reduction in egg counts) and 4 had severe resistance (less than 60% reduction).

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Prevalencia De La Resistencia A Fenbendazole En Nematodos Ovinos En El Noroeste De India

Resumen Se llevó a cabo un estudio entre marzo y septiembre de 1992, para determinar la prevalencia de resistencia a fenbendazole de nemátodos ovinos en 32 rebaños con un manejo tradicional y 22 con un manejo intensivo en 3 fincas. El fenbendazole, un antihelmíntico comunmente usado, se dosificó a la dosis recomendada de 5 mg/kg de peso vivo. La eficacia fue determinada sobre la base del porcentaje de reducción en el conteo de huevos de estróngilus y los cultivos de larvas antes y entre 7 y 10 días después del tratamiento. Ninguno de los apriscos manejados tradicionalmente mostraron resistencia y todos tuvieron más del 99% de reducción en el conteo de huevos después del tratamiento.De los rebaños manejados intensivamente, 15 tuvieron una ligera resistencia al fenbendazole (entre 60 y 90% de reducción en el conteo de huevos) y 4 tuvieron resistencia marcada (menos de 60% de reducción).

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Prevalence De La Resistance Au Fenbendazole De Nematodes Chez Des Ovins Du Nord-Ouest De L'Inde

esumé Une enquête a été entreprise de mars à septembre 1992 pour évaluer la prévalence de la résistance au fenbendazole de nématodes dans 32 troupeaux de moutons conduits en élevage traditionnel et 22 en élevage intensif appartement à 3 fermes. Le fenbendazole, anthelminthique communément utilisé, a été administré à la dose recommandée de 5 mg/kg de poids vif. Son efficacité a été déterminée à partir de la réduction du pourcentage du nombre d'oeufs de strongles dans les fèces et à partir de cultures de larves avant et entres le 7e et 10e jours après le traitement. Aucun des troupeaux en élevage traditionnel n'a montré de résistance au médicament et tous ont présenté une réduction de 99 p.100 du nombre d'oeufs dans les féces après le traitement. Une légère résistance au produit (entre 60 et 90 p.100 de réduction du nombre d'oeufs) a cependant été démontrée dans 15 des 22 troupeaux en élevage intensif et une résistance grave (réduction de moins de 60 p.100) dans 4 autres.