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Anthelmintic resistance (AR) is a growing concern for effective parasite control in farmed ruminants globally. Combatting AR will require intensified and integrated research efforts in the development of innovative diagnostic tests to detect helminth infections and AR, sustainable anthelmintic treatment strategies and the development of complementary control approaches such as vaccination and plant-based control. It will also require a better understanding of socio-economic drivers of anthelmintic treatment decisions, in order to support a behavioural shift and develop targeted communication strategies that promote the uptake of evidence-based sustainable solutions. Here, we review the state-of-the-art in these different fields of research activity related to AR in helminths of livestock ruminants in Europe and beyond. We conclude that in the advent of new challenges and solutions emerging from continuing spread of AR and intensified research efforts, respectively, there is a strong need for transnational multi-actor initiatives. These should involve all key stakeholders to develop indicators of infection and sustainable control, set targets and promote good practices to achieve them.

Proanthocyanidins (PAC) are dietary compounds that have been extensively studied for beneficial health effects due to their anti-inflammatory properties. However, the structure-function relationships of PAC and their mode-of-action remain obscure. Here, we isolated a wide range of diverse PAC polymer mixtures of high purity from plant material. Polymer size was a key factor in determining the ability of PAC to regulate inflammatory cytokine responses in murine macrophages. PAC polymers with a medium (9.1) mean degree of polymerization (mDP) induced substantial transcriptomic changes, whereas PAC with either low (2.6) or high (12.3) mDP were significantly less active. Short-term oral treatment of mice with PAC modulated gene pathways connected to nutrient metabolism and inflammation in ileal tissue in a polymerization-dependent manner. Mechanistically, the bioactive PAC polymers modulated autophagic flux and inhibited lipopolysaccharide-induced autophagy in macrophages. Collectively, our results highlight the importance of defined structural features in the health-promoting effects of PAC-rich foods., Andersen-Civil et al isolated a range of proanthocyanidin (PAC) polymer mixtures from plant material and demonstrated that polymer size was a key determinant of the ability of PACs to regulate inflammatory responses in murine macrophages, and intestinal tissues following oral intake. The PAC polymers modulated autophagic flux and inhibited lipopolysaccharide-induced autophagy in macrophages, which could help to explain the health benefits of PAC-rich food.

Phytonutrients such as cinnamaldehyde (CA) have been studied for their effects on metabolic diseases, but their influence on mucosal inflammation and immunity to enteric infection are not well documented. Here, we show that consumption of CA significantly down-regulates transcriptional pathways connected to inflammation in the small intestine of mice. During infection with the enteric helminth Heligomosomoides polygyrus, CA-treated mice displayed higher growth rates and less worms, concomitant with altered T-cell populations in mesenteric lymph nodes. Furthermore, infection-induced changes in gene pathways connected to cell cycle and mitotic activity were counteracted by CA. Mechanically, CA did not appear to exert activity through a prebiotic effect, as CA treatment did not significantly change the composition of the gut microbiota. Instead, in vitro experiments showed that CA directly induced xenobiotic metabolizing pathways in intestinal epithelial cells and suppressed endotoxin-induced inflammatory responses in macrophages. Thus, CA down-regulates inflammatory pathways in the intestinal mucosa and regulates host responses to enteric infection. These properties appear to be largely independent of the gut microbiota and instead connected to CA’s ability to induce antioxidant pathways in intestinal cells. Our results encourage further investigation into the use of CA and related phytonutrients as functional food components to promote intestinal health in humans and animals.

We tested the practical application of an anaemia scoring chart (the FAMACHA chart) as a method for controlling Haemonchus contortus in goats kept under smallholder conditions in a sub-humid area of Central Kenya. The objectives were: (1) to test the accuracy of the FAMACHA chart in identifying anaemic goats (PCV< or =18); (2) to quantify the proportion of goats left untreated at farm level when using the chart. On each of two farms, Small East African goats of various ages were allocated to two treatment groups; a FAMACHA group (F1 (n=34) and F2 (n=31) on farms 1 and 2, respectively) and a control group (C1 (n=34) and C2 (n=30)). In F1 and F2 goats with a FAMACHA score of 3, 4 or 5 were treated with anthelmintic after scoring. In C1 and C2 goats were treated every 4 weeks from 15 February to 20 July. Every 2 weeks all goats were scored with the FAMACHA chart and weighed. Furthermore, faecal samples were collected for faecal egg counts (FEC) and blood samples were collected for packed cell volume (PCV) determination. H. contortus was found to be the predominant nematode on both farms. The mean FECs were higher on farm 1 compared to farm 2, while in contrast the mean PCV levels were lowest on farm 2. The latter was most likely due to the presence of Fasciola spp., flea and tick infections on farm 2. The accuracy of the chart was evaluated by using PCV as the gold standard for anaemia (PCV< or =18%). The mean percentage of false-negative scorings per sampling was 0.7% on farm 1 and 1.6% on farm 2, while the mean percentage of false-positive scorings was 9.7% and 21.4%, respectively. It is most likely that the accuracy of the chart was negatively affected by the concurrent parasite infections on farm 2. The mean proportion of untreated goats per sampling was 89% and 77% on farm 1 and farm 2. It was concluded that the FAMACHA chart can be a valuable tool for decision-making in control of H. contortus in goats kept under smallholder conditions, without morbidity or mortality unacceptable to the farmer. The application may further reduce the risk of development of anthelmintic resistance by increasing refugia. However, caution should be taken under conditions where other anaemia-causing parasites are present (e.g. Fasciola spp. and ecto-parasites), since this possibly decreases the accuracy of the FAMACHA chart.

Boar taint is an off-flavour of pork caused primarily by a microbial breakdown product, skatole and a testicular steroid, androstenone. As skatole is produced in the large intestine from tryptophan, it is possible that some ‘bioactive’ ingredients could modify protein fermentation and, in the process, diminish boar taint. The aim of this study was to examine the effect of inulin-rich chicory roots (Cichorium intybusL.) on boar taint. In the first of three trials individually penned, entire males and females were given an organic concentrate in which 0·25 of the daily energy intake was replaced with crude chicory roots for 9 or 4 weeks prior to slaughter. In the second trial, entire male pigs were given diets that included, either crude chicory roots, dried chicory roots, or inulin (extracted from chicory roots) for 6 weeks pre-slaughter. In the third trial, intact male pigs were given the dried chicory diet for either 2 or 1 week before slaughter. In all trials the chicory diets were offered on a scale at 0·95 of the Danish recommendation for energy intake, and pig performance was compared with a control group given the organic concentrate at 0·95 of recommended energy intake plus silage ad libitum. In trial 1 an additional control group was offered the organic concentrate at a daily energy intake level of 1·0 of Danish recommendations. The pigs in trials 1, 2, and 3 were slaughtered at an average live weight of 118, 124, and 110 kg, respectively, in order to ensure that they had achieved sexual maturity. Overall, skatole concentrations in blood plasma and backfat at slaughter were reduced to almost zero levels by including crude or dried chicory or inulin in the diet. This occurred irrespective of sex and length of feeding period (1 to 9 weeks). In trial 3 a significant effect on blood plasma concentration was observed after 3 days of feeding a diet containing dried chicory. The only significant reduction in plasma androstenone levels was detected in pigs given the crude chicory for a 9 week duration in trial 1. The production and proportion of lean was generally not affected by the addition of either form of chicory to the diets in trials 1 and 2. Therefore, dried chicory may be the most suitable form for commercial use because it: had no initial adverse effects on food intake, consistently reduced skatole without reducing performance, was easy to handle throughout the entire year and is relatively inexpensive.

In Europe, organic beef production is based on grazing in summer and feeding a minimum of 60% roughage during the whole year. Although these recommendations were intended to improve animal health and welfare, several factors may cause problems in organic beef production systems. This paper gives an overview of welfare, health and product quality in organic beef production, with emphasis on organic steer production based on dairy-breed bull calves. A short overview of different production systems, highlighting the effect on health and welfare, is also given. Feeding aspects are discussed. Farm studies have shown that organic steer production involves large amounts of roughage; only small quantities of cereals are used compared to conventional production of bulls and calves. Fattening of organic steers may result in metabolic disorders due to sudden changes in the feed ration when changing from high roughage to high cereal content. Various problems relating to the production system are discussed. Subjective monthly observations indicate a good level of general health and welfare in organic steer production systems. On pasture, parasitic infection is the primary factor affecting animal health and productivity of organic beef. Rearing of young calves and the utilization of marginal grazing areas requires further attention. The effect of castration on health and welfare, and the effect of castration age and method, are also discussed. Product quality of organic beef is affected by the production system, especially sex, grazing and exercise. Grazing and exercise, which are inevitable components of an organic beef production system, may affect the eating quality due to darker meat color, risk of off-flavor, yellow fat, and a higher content of unsaturated fatty acids, including conjugated linoleic acid (CLA). Nevertheless, the overall effect on sensory attributes may be of minor importance. For the future, feeding large amounts of roughage, combined with a high bioactive forage content, could be one way of improving the product quality of organic beef.

Organic steer production demands several decisions concerning grazing strategy, feeding level in the winter and factors such as slaughter weight and length of the fattening period. The production system can be difficult to optimise, therefore the objective of this study was to develop a model to optimise the grazing strategy, feed level in winter and time of fattening and slaughter in organic steer production with regard to economic output at steer level. The steer model is a four-level hierarchical Markov process with decisions defined at three levels. Decisions taken in the model include grazing strategy (permanent or ryegrass/clover pasture), feed level in winter (high and low), time for beginning of fattening (age 19–27 months) and time of slaughter (age 19–30 months). Overall optimal strategies at child level 1 with regard to economic output per produced steer were low feeding level in the winter period, grazing on permanent pastures in the first grazing season, whereas ryegrass/clover pastures gives the optimal net return per steer in the second and third grazing season. The optimal strategies from the model suggested that the effect of fattening in steer production might be overstated. It was concluded that the natural well-defined phases in organic steer production are well suited to be analysed by a multi-level hierarchic Markov processes (MLHMP).

This study was carried out to determine the effects of Acacia karoo and Acacia nilotica diets on Haemonchus contortus infections in goats. Twenty-four Boer goats of mixed sex (live weight 17-22 kg) were randomly assigned to four treatment groups, namely: A. nilotica (AN) group, A. karoo (AK) group, control infected with H. contortus (HC) group and the non-infected control (NHC) group. Animals in the AN, AK and HC groups were orally infected with a single dose of 3000 HC third stage larvae. The AN and AK groups had dried leaves of AN and AK, respectively, included in their basal diet at a rate of 40% dry matter (DM) while the HC and NHC groups had the basal diet throughout the experiment. All animals received a total feed allowance of 500 g DM per day and Katambora Rhodes grass hay ad libitum for roughage. Parameters measured included faecal egg counts and live weight. At the end of the experiment, three animals from each group were slaughtered and abomasal worm burdens were determined. A significant decrease in the faecal egg counts was recorded in animals in the AK group (P

This paper focuses on the changes in production, herd health and veterinary treatments in Danish organic dairy herds during approximately eleven years based on historic data from herds converted to organic milk production before 1990 (old organic herds) compared to herds converted in 1995 and 1999-2000 and herds that are still conventional. Herd size, milk production, the shape of the lactation curve, somatic cell counts and veterinary treatments for mastitis, retained placenta and ketosis are compared over time and between herd groups. The old organic herds differed from the other three herd groups by having lower milk production per cow, lower somatic cell counts and fewer treatments of mastitis. Herds converted in 1995 and 1999-2000 were comparable to the conventional herds before conversion for all analyzed parameters. However, herd size was larger than both the older organic herds and the conventional herds after conversion. Production was about 2 kg energy corrected milk lower per cow per day than before conversion and compared to the conventional herds. In the herds converted in 1999-2000 little difference could be seen in relation to udder health after conversion when compared to conventional herds. The organic herds had fewer treatments for retained placenta and ketosis than the conventional herds. The shape of the lactation curves changed over the 11 year period with better persistency from day 60 to day 305 in all herd groups except for the old organic herds, which had the best persistency in 1990.

International audience; Parasitic infections with gastrointestinal nematodes (GINS) still represent a worldwide major pathological threat associated with the outdoor production of various livestock species. Because of the widespread resistance to synthetic chemical anthelmintics, there is a strong impetus to explore novel approaches for a more integrated management of these infections. The use of nutraceuticals in the control of GINs is one of the alternatives which has been widely studied for 20 years. The objectives of this review are: (i) to define and illustrate the concept of 'nutraceutical' in the context of veterinary parasitology based on data obtained on the most studied models to control GINs in small ruminants, the tannin-containing legumes (Fabaceae); (ii) to illustrate how the 'nutraceutical concept' could be expanded to other plants, other livestock production systems and other GI parasitic diseases, and (Hi) to explain how this concept is opening up new research fields for better understanding the interactions between the host, the digestive parasites and the environment.

The objectives of this study were to quantify how many organic dairy farmers sell bull calves to fattening on other farms and to analyse management strategies concerning dairy bull calves, including selling of calves, ethical considerations and management on already existing beef production. A pilot project with interview of 10 organic dairy farmers was followed by a questionnaire survey involving all organic dairy farmers in Denmark (671) and 168 organic plant breeders. Eight percent of all dairy bull calves born on organic dairy farms were killed, 66% were sold to conventional farms, 6% were sold to organic farms and 20% remained on the farm of birth. However, 59% of the farmers, selling their bull calves, wished to keep the bull calves on their own farm. The main problems with keeping the calves in order of decreasing importance were: lack of stall capacity, expected poor production economy and shortage of own foodstuff. The main reason for keeping the bull calves on 29% of the farms was the wish for a holistic production system. Most of these farmers had steer production (66%), because of high utilization of roughage, the capacity to graze marginal areas and their calm temperament. Marginal areas were utilised for beef production on 59% of the farms. It is concluded that the majority of the bull calves born on organic dairy farms are not reared on organic farms. Co-operation with plant breeders should be strengthened to stimulate rearing of dairy breed bull calves in an organic way and to utilise resources in organic farming in the best way.

In November 1997, Cryptosporidium andersoni, for the first time, was isolated from a Danish heifer. The isolate was characterised morphologically, molecularly, and furthermore inoculated into mice and one calf. Data on the distribution of cryptosporidia in the herd of origin were obtained at two separate visits in December 1997 and April 1998. C. andersoni was detected in 27 (19.0%) of 142 cattle examined at the first visit, whereas C. parvum was found in six (4.2%). At the following visit 42 (28.0%) of 150 cattle excreted C. andersoni, while 25 (16.7%) were positive for C. parvum. Oocysts of the Danish C. andersoni isolate were ovoid, 7.3 (6.5–8.0)×5.7 (5.0–7.0) μm2 (n=25), with smooth, colourless, single layer oocyst wall and distinct oocyst residuum. The length to width ratio was 1.27 (1.14–1.40, n=25). The identification was verified by sequencing of a 246 bp fragment of the rDNA, which was identical to Cryptosporidium muris, the calf genotype (AF093496). The Danish C. andersoni isolate was not transmissible to mice, whereas oocysts were detected in the faeces of one experimentally infected calf from 25 days post-infection (DPI) and shed intermittently at low numbers until 165 DPI, the day of euthanasia. No macroscopic or microscopic changes that could be attributed to infection with C. andersoni were seen in the gastro-intestinal tract of the experimentally infected calf following necropsy and histological examination. This is to our knowledge the first report of C. andersoni in Scandinavia.

The impact of gastrointestinal nematodes on health and production of goat was investigated in a low potential area (Ecozone 3) of Kenya. The study involved 44 Small East African goat kids aged 4–5 months divided into two replicate groups (treated and control) and set stocked on pasture for 7 months through a dry season and a short rainy season from May to December 1998. The treated group received fortnightly albendazole treatment while the control group were untreated. Live weight, packed cell volume (PCV), faecal egg counts and pasture larval counts were measured every 2 weeks. Half of the animals from each group were randomly selected for slaughter, total worm counts and identification at the end of December. The faecal egg counts for the treated group remained low while those of the control group rose gradually through the study period. The counts were higher during the short rainy season. The control group lost weight during the dry season and underwent compensatory growth during the short rainy season. The treated group maintained their weight during the dry season and also showed compensatory growth during the short rainy season. Comparing the weight at the start and end of the study, the treated group gained an average of 3.1±0.3 kg while the control group gained 1.1±0.2 kg. Two goats in the control group died at the end of the dry season after showing clinical signs of parasitic gastroenteritis. Two others in the same group were given salvage treatments during the same period. The PCV (%) values were reduced during the dry season in both groups. The values were higher in the treated group. At slaughter the mean group worm counts for the control group was 1133±387 while that for the treated group was 123±56. In all the animals Haemonchus contortus was the main nematode recovered. Hypobiotic larvae were recovered in the abomasum. The pasture larval counts were significantly lower in the paddocks grazed by the treated group in both the dry and short rainy season compared to that grazed by the control group. It was concluded that gastrointestinal helminths cause production losses, weight loss and mortalities in goats. H. contortus was the main nematode infecting the goats in this area. The albendazole treatment prevented parasitic gastroenteritis, weight loss and mortalities.

The effect of gastrointestinal nematode infections on bone development was investigated in growing sheep on pasture. Forty-five weaned lambs from six groups in a two-factorial design incorporating stocking rate (SR; low, medium and high) and presence or absence of infection on pasture were sampled in the late grazing season. Worm counts were performed at slaughter, and the left metacarpal bones were excised for bone assessment. Faecal egg counts and worm burdens, primarily of Ostertagia circumcincta and Trichostrongylus vitrinus , were considerably higher in the high SR infected group (“I-High”) than in comparable animals at low or medium SRs, whereas uninfected groups showed negligible egg excretion. Clinical biochemistry revealed significantly reduced serum concentrations of albumin, calcium and alkaline phosphatase in infected lambs. Nematode infections were associated with significant reductions in bone mineral density (30% at high SR), measured by dual energy X-ray absorptiometry, and in bone size (9%). Histomorphometry indicated thinning of the trabecular structure and reduced bone formation in the infected groups, particularly the I-High group. Bone mineral density, bone tissue volume and structural changes were strongly associated with log-transformed worm counts. The study showed that lambs suffering from moderate to heavy degrees of naturally acquired gastrointestinal nematode infection developed marked osteopenia after weaning, i.eduring the later part of the grazing season.

A survey of gastrointestinal parasite infections of young ( 12 months old) dairy cattle on 16 farms in Kiambu District, Kenya was conducted during a dry season (September 1991 to January 1992) and during a wet season (March to July 1992). The survey was based on monthly coproparasitological examination of cohorts and worm counts in tracer calves. The effects of age, sex, farm and season on the prevalence and intensity of helminth and coccidial infections were determined. Faecal egg and oocyst counts revealed that the overall prevalences were: strongyles (including trichostrongyles) (85.5%), liver flukes (Fasciola gigantica) (34.0%), coccidia (30.9%) and tapeworms (9.6%). Eight species of the protozoan Eimeria were identified, the most prevalent species being E. bovis and E. zuernii. The most prevalent nematode genera were Haemonchus, Cooperia, Oesophagostomum and Trichostrongylus. Season, farm and age of the animals had a significant (p 0.05) effect on the prevalence or intensity of infections. A higher intensity of infection with strongyles and coccidia was found in the wet season than in the dry season (p 0.05) between immatures and adult cattle.

D-Amino acid containing peptides have been found to be responsible for sawfly larvae poisoning in many parts of the world. These compounds, unique in the animal kingdom, were isolated from three different species of sawfly indigenous to Australia, Denmark and South America. The octapeptide, lophyrotomin, is the major toxin in the Australian and Danish species and is present in small amounts in the South American sawfly. Pergidin, the main toxin in the South American sawfly, is a heptapeptide containing a phosphoseryl residue. This, as far as we are aware, is the first example of such a peptide to be isolated from an animal source. Small amounts of pergidin have been found in the other two species. All available evidence suggests that both peptides are biosynthesised 'de novo possibly as a protective device, however it cannot be excluded that microorganisms may be responsible. These compounds are stable to enzymatic breakdown because of their configuration and their strong chemical bonding and lipophilic character provide a potential for residues to remain in the host animal and cause significant changes. (C) 1999 Elsevier Science Ltd. All rights reserved.

Ascaris suum is one of the most prevalent nematode parasites in pigs and causes significant economic losses, and also serves as a good model for A. lumbricoides, the large roundworm of humans that is ubiquitous in developing countries and causes malnutrition, stunted growth and compromises immunity to other pathogens. New treatment options for Ascaris infections are urgently needed, to reduce reliance on the limited number of synthetic anthelmintic drugs. In areas where Ascaris infections are common, ethno-pharmacological practices such as treatment with natural plant extracts are still widely employed. However, scientific validation of these practices and identification of the active compounds are lacking, although observed effects are often ascribed to plant secondary metabolites such as tannins. Here, we extracted, purified and characterised a wide range of condensed tannins from diverse plant sources and investigated anthelmintic effects against A. suum in vitro. We show that condensed tannins can have potent, direct anthelmintic effects against A. suum, as evidenced by reduced migratory ability of newly hatched third-stage larvae and reduced motility and survival of fourth-stage larvae recovered from pigs. Transmission electron microscopy showed that CT caused significant damage to the cuticle and digestive tissues of the larvae. Furthermore, we provide evidence that the strength of the anthelmintic effect is related to the polymer size of the tannin molecule. Moreover, the identity of the monomeric structural units of tannin polymers may also have an influence as gallocatechin and epigallocatechin monomers exerted significant anthelmintic activity whereas catechin and epicatechin monomers did not. Therefore, our results clearly document direct anthelmintic effects of condensed tannins against Ascaris and encourage further in vivo investigation to determine optimal strategies for the use of these plant compounds for the prevention and/or treatment of ascariosis.

The two geohelminths,Ascaris lumbricoidesandTrichuris trichiura, infect more than a billion people worldwide but are only reported sporadically in the developed part of the world. In contrast, the closely related speciesA. suumandT. suisin pigs have a truly global distribution, with infected pigs found in most production systems. In areas where pigs and humans live in close proximity or where pig manure is used as fertilizer on vegetables for human consumption, there is a potential risk of cross-infections. We therefore review this relationship betweenAscarisandTrichurisin the human and pig host, with special focus on recent evidence concerning the zoonotic potential of these parasites, and identify some open questions for future research.

Effects of voluntary intake of two different forms of diets on forestomach, bone, and digital development in goats were studied. Twenty male kids of the Danish Landrace were investigated from the first month of life to the age of 4 mo. Ten were fed a ration of hay plus pelleted protein-barley concentrates (high energy concentrate; group A), while the other ten were given hay plus a pelleted ration consisting mainly of alfalfa (green forage pellets; group B). Serial radiographs of the right metacarpal bone were taken at 5, 12 and 17 wk of age to assess bone development. At postmortem forestomach structures were studied macroscopically and microscopically. Carcass quality was also evaluated. Goats in group A had more pronounced bone development compared to group B. Differences in bone development were attributed to excess calcium and low phosphorus in diet B. Goats on diet A had more developed forestomach than those on diet B, indicating that rumen epithelial development was an adaptive process associated with diet induced changes and patterns of rumen fermentation. Body condition and carcass quality of goats in group A was better compared to goats on green forage pellets. The study showed that goats on voluntary intake of high energy concentrates can develop without rumen degenerative lesions or laminitis and can tolerate ad libitum concentrates without adverse effects to increase productivity.

Twenty male kids of the Danish Landrace, in two groups of ten each, were fed ad libitum whole barley and pelleted protein supplement (group A) or forage pellets (mostly lucerne) (group B), from 1 mo of age until slaughter 3 mo later. Both groups had free access to hay. Apart from subclinical acidosis initially, group A remained healthy, showed acceptable weight gain (197 Mg, inorganic P, glucose, Se, and produced a significantly lower mean weight gain (111 g/day, P

Helminths in pigs have generally received little attention from veterinary parasitologists, despite Ascaris suum, Trichuris suis, and Oesophagostomum sp. being common worldwide. The present paper presents challenges and current research highlights connected with these parasites. In Danish swine herds, new indoor production systems may favour helminth transmission and growing knowledge on pasture survival and infectivity of A. suum and T. suis eggs indicates that they may constitute a serious threat to outdoor pig production. Furthermore, it is now evident that A. suum is zoonotic and the same may be true for T. suis. With these 'new' challenges and the economic impact of the infections, further research is warranted. Better understanding of host-parasite relationships and A. suum and T. suis egg ecology may also improve the understanding and control of human A. lumbricoides and T. trichiura infections. The population dynamics of the three parasites are well documented and may be used to study phenomena, such as predisposition and worm aggregation. Furthermore, better methods to recover larvae have provided tools for quantifying parasite transmission. Thus, an on-going study using helminth naive tracer pigs has surprisingly demonstrated that soil infectivity with A. suum and T. suis increases during the first 2-3 years after pasture contamination. Though all three helminth species stimulate the Th2 arm of the immune system, Oesophagostomum seems weakly immunogenic, perhaps via specific modulation of the host immune system. A. suum and T. suis potently modulate the host immune response, up-regulating Th2 and down-regulating Th1. As a consequence, A. suum may compromise the efficacy of certain bacterial vaccines, whereas T. suis, which establish only short-term in humans, is a favourite candidate for down-regulating autoimmune Th1-related diseases in man. Some basic research findings have offered new possibilities for future sustainable control measures. For example, the heredity of host resistance to A. suum and T. suis is so high that breeding for resistant pigs may be a possibility. Experimental studies have demonstrated that fermentable dietary carbohydrates have an antagonistic effect on Oesophagostomum and to a lesser extent on T. suis and A. suum, whereas egg-destroying microfungi may be used to inactivate the hard-shelled A. suum and T. suis eggs in the environment. Helminth control in Denmark has previously relied solely on anthelmintic treatment in herds with low helminth transmission. When indoor transmission rates increase, or in outdoor herds with high pasture contamination levels, medication may advantageously be combined with sustainable control measures, such as selected pig genomes, bioactive forages, and egg-destroying microfungi.

Taenia solium is an important zoonosis in many developing countries. Cysticercosis poses a serious public health risk and incurs sizeable economic losses to pig production. Because data on the epidemiology of porcine cysticercosis in Mozambique are scarce, the present study was conducted to determine the prevalence and risk factors for porcine cysticercosis. A cross-sectional survey was carried out in 11 villages in Angónia district, Tete province in northwestern Mozambique. Between September and November, 2007, a total of 661 pigs were tested serologically and examined by tongue inspection. Serum samples were tested for the presence of circulating parasite antigen using a monoclonal antibody-based sandwich enzyme-linked immunosorbent assay (Ag-ELISA). In addition, a questionnaire survey to collect information on pig production, occurrence and transmission of porcine cysticercosis, risk factors and awareness of porcine cysticercosis was conducted in the selected households from which pigs were sampled. Two hundred thirty-one samples (34.9%) were found positive by the Ag-ELISA, while by tongue inspection on the same animals cysticerci were detected in 84 pigs (12.7%). Increasing age (OR = 1.63; 95% CI = 1.13–2.37) and free-range pig husbandry system (OR = 3.81; 95% CI = 2.08–7.06) were important risk factors for porcine cysticercosis in the district. The present findings indicate that porcine cysticercosis is endemic in the region, and that increasing pig age and pig husbandry practices contribute significantly to porcine cysticercosis transmission. Further epidemiological studies on the prevalence and transmission of porcine cysticercosis in rural communities in Mozambique are needed to enable collection of more baseline data and implementation of effective control strategies within the country., Author Summary Porcine cysticercosis is an infection of pigs caused by the larval stage of Taenia solium, a tapeworm that causes taeniosis in humans. The disease is very common in pigs from many developing countries around the world and poses a serious public health risk and causes significant economic losses in pig production. In Mozambique there is scanty information regarding the occurrence of this disease. Our work conducted in Angónia district, northwestern Mozambique, allowed us to collect important information to evaluate the magnitude and identify the risk factors associated with porcine cysticercosis. This study found that cysticercosis is highly prevalent in pigs and that the free-range husbandry system was by far the main risk factor for the transmission of the disease in the district. These findings should help in the design of control strategies to prevent continuous transmission of this disease in Angónia and in Mozambique.

Helminth infections are a major cause for reduced productivity in livestock, particularly those owned by the poor worldwide. Phytomedicine has been used for eons by farmers and traditional healers to treat parasitism and improve performance of livestock, and many modern commercial medicines are derived from plants. However, scientific evidence on the anti-parasitic efficacy of most plant products is limited, regardless of their wide ethnoveterinary usage. Scientific validation of the anti-parasitic effects and possible side-effects of plant products in ruminants is necessary prior to their adoption as a novel method for parasite control. A variety of methods has been explored to validate the anthelmintic properties of such plant remedies, both in vivo and in vitro. In vitro assays are useful as pre-screens of activity and are mainly performed with the free-living rather than parasitic stages of nematodes. Concentrations of potentially active substances used in vitro do not always correspond to in vivo bioavailability. Therefore, in vitro assays should always be accompanied by in vivo studies when used to validate the anthelmintic properties of plant remedies. In vivo controlled studies have shown that plant remedies have in most instances resulted in reductions in the level of parasitism much lower than those observed with anthelmintic drugs. Whether it is necessary or not to achieve very high efficacy in order for plant remedies to have a role in the control of parasitism depends on the determination of biologically important levels of reduction of parasitism and it will be required prior to the wide-scale use of plant products for parasite control. Similarly, standardisation of validation studies in reference to the numbers of animals required for in vivo studies to measure direct anthelmintic effects of a plant needs to be established. Although in many cases the active compounds in the herbal remedies have not been fully identified, plant enzymes, such as cysteine proteinases, or secondary metabolites, such as alkaloids, glycosides and tannins have shown dose-dependent anti-parasitic properties. However, as some of the active compounds may also have anti-nutritional effects, such as reduced food intake and performance, it is essential to validate the anti-parasitic effects of plant products in relation to their potential anti-nutritional and other side effects. A concerted effort on isolation, development, and validation of the effects of these herbal remedies will have to be undertaken before their wider acceptance.

Development of resistance to anthelmintic drugs by horse strongyles constitutes a growing threat to equine health because it is unknown when new drug classes can be expected on the market. Consequently, parasite control strategies should attempt to maintain drug efficacy for as long as possible. The proportion of a parasite population that is not exposed to anthelmintic treatment is described as being “in refugia” and although many factors affect the rate at which resistance develops, levels of refugia are considered the most important as these parasites are not selected by treatment and so provide a pool of sensitive genes in the population. Accordingly, treatment should be avoided when pasture refugia are small because such treatments will place significant selection pressure for resistance on worm populations. Given this new paradigm for parasite control, it has become important to identify seasons and circumstances wherein refugia are diminished. Free-living stages of equine strongyles are highly dependent on climatic influences, and this review summarises studies of strongyle development and survival under laboratory and field conditions in Northern (cool) temperate, Southern (warm) temperate and subtropical/tropical climates. In Northern temperate climates, refugia are smallest during the winter. In contrast, refugia are lowest during the summer in warm temperate and subtropical/tropical climates. Although adverse seasonal changes clearly have significant effects on the ability of free living stages of strongyle nematode parasites to survive and develop, available data suggest that climatic influences cannot effectively “clean” pastures from one grazing season to the next.

Apart from the obvious role of plants in herbivore nutrition, they are also a rich source of bioactive products that can operate either to the benefit or the detriment of grazing animals. Here, we review the available evidence for the potential beneficial effects that plant-derived bioactive substances can have on gastrointestinal parasites. Tannin-rich plants have attracted most attention for their effect on internal nematodes in ruminants. These plants could act through direct antiparasitic activity but might also act indirectly by increasing host resistance. The effects vary with the species of plant, parasite and host. More research is required to understand better the mechanisms of action, and therefore make more pertinent use of these bioactive plants in livestock systems.

EPIDEMIOLOGIE DES NEMATODES GASTRO-INTESTINAUX CHEZ LES CHEVRES DANS LES ZONES A FAIBLES POTENTIALITES DU DISTRICT DE THIKA Résumé La prévalence et l'intensité des infections par les nématodes gastro-intestinaux chez les chèvres dans quatre petites fermes (< 5ha avec moins de 30 chèvres) dans les zones à faibles potentialités du district de Thika au Kenya, ont fait l'objet d'études pendant un an. La prévalence et l'intensité des infections variaient selon les fermes et les conditions atmosphériques. Les différences relatives aux groupes d'âge étaient notables uniquement pendant la saison sèche lorsque le nombre d'oeufs de nématodes par gramme de fèces était plus élevé chez les chevreaux que chez les jeunes et les adultes. Le nombre d'oeufs de nématodes dans les fèces augmentait pendant les longues pluies (avril-juin) et durant les courtes et fortes pluies vers la fin de la période d'étude (novembre-février). Des traitements anthelminthiques ont été administrés à toutes les chèvres dans les fermes en fonction du nombre d'oeufs de nématodes dans les fèces. Quatre traitements ont été donnés pendant la saison des pluies et un traitement à la fin de la saison sèche en septembre, et il s'ensuivait une réduction du nombre d'oeufs de nématodes dans les fèces. Haemonchus contortus était le principal nématode recueilli des coprocultures. Il a été conclu que la prévalence et l'intensité des infections par les helminthes gastro-intestinaux chez les chèvres dans cette région variaient avec les saisons et que Haemonchus contortus était le principal nématode qui infectait les chèvres. Summary The prevalence and intensity of gastrointestinal nematode infections in goats in four small scale farms (< 5ha each with less than 30 goats) in the low potential areas of Thika District, Kenya, was studied over a period of one year. The prevalence and intensity of infection varied with the farms and the weather conditions. The differences in the age groups were observed only during the dry season when the kids had higher eggs per gram of faeces (EPG's) than the young and the adults. There was a rise in faecal egg counts during the long rains (April - June) and during the heavy short rains experienced towards the end of the study period (November - February). Anthelmintic treatments were given to all the goats on the farms depending on the level of the faecal egg counts. Four treatments were given during the rainy season (months) and one at the end of the dry season in September. These treatments were followed by reduced faecal egg counts. Haemonchus contortus was the main nematode recovered from coprocultures. It was concluded that the prevalence and intensity of gastrointestinal helminth infection in goats in this area varied with seasons and that H. contortus was the main nematode infecting the goats. Bull Anim. Hlth. Prod. Afr. (2004) 53,5-12

Collectively, nematode parasites of domestic ruminants continue to pose the greatest disease problem in grazing livestock systems worldwide, despite the powerful and extensive chemotherapeutic arsenal available for their control. The widespread development of anthelmintic resistance, particularly in nematode parasites of small ruminants, and the trend towards non-chemical (ecological, organic, green) farming of livestock has provided an impetus for the research and development of alternative parasite control methods. This article provides a brief overview of the non-chemotherapeutic options for parasite control and how they might play a role either in organic farming or in other low-input farming systems.

Organic and other non-intensive animal production systems are of growing importance in several countries worldwide. In contrast to conventional farms, parasite control on organic farms is affected by several of the prescribed changes in management e.g. access to the outdoors in the summer and in most countries, a ban on preventive medication, including use of anti-parasiticides. Organic animal production relies heavily on grazing, and pasture or soil related parasites are thus of major importance. Several studies in northern temperate climate have indicated that outdoor production of pigs, primarily sows, and laying hens results in heavier and more prevalent helminth infections compared to conventional intensive production under indoor conditions. In organic dairy cattle, parasitic gastroenteritis in heifers may be more prevalent. In a short to medium term perspective, integrated control may combine grazing management with biological control using nematophagous micro-fungi, selected crops like tanniferous plants and on conventional farms, limited use of anti-parasiticides. At present, the non-chemotherapeutic control of pasture related infections is based mainly on grazing management strategies. Preventive strategies, where young, previously unexposed stock, are turned out on parasite-free pastures, can be used for grazing first season dairy heifers and in all-in-all-out poultry production. Evasive strategies aim at avoiding disease producing infections of a contaminated area by moving to a clean area and may be relevant for ruminants and pigs. In cattle, effective control of nematodes can be achieved by repeated moves of the herd or alternate grazing with other species. High stocking rates seem to be an important risk factor. In pig production, the effect of paddock rotation on parasite infections is largely unknown and studies are warranted. Control of nematodes by larvae-trapping fungi, or perhaps in the future by egg-destroying fungi, looks promising for ruminants and certain monogastric animals but delivery systems and practical dosing regimes integrated with grazing management have to be developed. In conclusion, good prospects are expected for acceptable parasite control without a heavy reliance on anti-parasiticides through integration of the above mentioned procedures but future studies are needed to confirm their efficacy under practical farming conditions.

Parasitic helminth infections can protect against allergic airway inflammation in experimental models and have been associated with a reduced risk of atopy and a reduced course of asthma in some observational studies. Although no clinical evidence exists to support the use of helminth therapy for allergic disease, the helminth Trichuris suis has demonstrated efficacy in treatment of inflammatory bowel disease.To determine efficacy of helminth therapy for allergic rhinitis.We conducted a double-blind, placebo-controlled, parallel group trial in which 100 subjects age 18 to 65 years with grass pollen-induced allergic rhinitis were randomly assigned to ingest a total of 8 doses with 2500 live T suis ova or placebo with an interval of 21 days. The primary outcome was a change in mean daily total symptom score for runny, itchy, sneezing nose (maximum change, 9.0) or in percentage of well days during the grass pollen season.Treatment with T suis ova (N = 49) compared with placebo (N = 47) caused transient diarrhea peaking at day 41 in 33% of participants (placebo, 2%), and increased eosinophil counts (P.001) and T suis-specific IgE (P.05), IgG (P.001), IgG(4) (P.003), and IgA (P.001), whereas there was no significant change in symptom scores (0.0; 95% CI, -0.5 to 0.4; P = .87), well days (3%; 95% CI, -9% to 14%; P = .63), total histamine (P = .44), grass-specific IgE (P = .76), or diameter of wheal reaction on skin prick testing with grass (P = .85) or 9 other allergens.Repeated treatment with the helminth T suis induced a substantial clinical and immunologic response as evidence of infection, but had no therapeutic effect on allergic rhinitis.

Summary Lambs harbouring an 8-week-old infection with Fasciola hepatica , together with fluke-free animals, were dosed orally with 2 g per kg body weight of sawfly larvae ( Arge pullata ). Fluke-free, non-dosed lambs and lambs infected only with F. hepatica served as controls. Clinico-pathological observations on sawfly-dosed, fluke-free lambs revealed the characteristic picture of sawfly poisoning. Four of six animals had to be killed in extremis. In contrast, sawfly-dosed, fluke-infected lambs exhibited only moderate clinico-pathological signs of sawfly poisoning and no deaths occurred. A reduction in the sawfly-induced liver pathology as a consequence of the concurrent F. hepatica infection was also noted. Possible factors responsible for the antagonistic effect of F. hepatica infection on sawfly poisoning in lambs are discussed.

Preparations derived from plants were the original therapeutic interventions used by man to control diseases (including parasites), both within humans and livestock. Development of herbal products depended upon local botanical flora with the result that different remedies tended to develop in different parts of the world. Nevertheless, in some instances, the same or related plants were used over wide geographic regions, which also was the result of communication and/or the importation of plant material of high repute. Thus, the Nordic countries have an ancient, rich and diverse history of plant derived anthelmintic medications for human and animal use. Although some of the more commonly used herbal de-wormers were derived from imported plants, or their products, many are from endemic plants or those that thrive in the Scandinavian environment. With the advent of the modern chemotherapeutic era, and the discovery, development and marketing of a seemingly unlimited variety of highly efficacious, safe synthetic chemicals with very wide spectra of activities, herbal remedies virtually disappeared from the consciousness – at least in the Western world. This attitude is now rapidly changing. There is a widespread resurgence in natural product medication, driven by major threats posed by multi-resistant pest, or disease, organisms and the diminishing public perceptions that synthetic chemicals are the panacea to health and disease control. This review attempts to provide a comprehensive account of the depth of historical Nordic information available on herbal de-wormers, with emphasis on livestock and to provide some insights on potentially rewarding areas of "re-discovery" and scientific evaluation in this field.

The mammary glands of 103 pasture-reared non-lactating, non-pregnant Merino ewes were infused via the teat canal with antigens prepared from the nematode Haemonchus contortus, and the inflammatory response to infusion assessed by washing the gland of its contents after 24 h and 14 days. The ewes were of two genotypes: one with proven high levels of resistance to infection with the nematode H. contortus, the other random-bred animals with relative susceptibility to infection. On day 0 of a H. contortus infection, one gland of the subgroups of both genotypes was infused with the antigen preparation. At the same time, the other gland of the random-bred ewes was infused with sterile physiological saline. A third group of infected random-bred ewes was infused with only sterile physiological saline. Similar infusions were performed on other subgroups on days 12, 21 and 35 of infection, which was then terminated with anthelmintic. A fourth group of uninfected random-bred control ewes was given both infusions 35 days after the other groups were infected. Sheep of the resistant genotype had lower worm egg counts and smaller reductions in blood packed cell volumes from day 21 of infection. Infusion of antigen had no effect on the course of infection and no effect on the response of the other gland, which had been infused with saline alone. The dominant leukocyte response from the antigen-infused gland was eosinophilia. On all days of infusion, and after both 24 h and 14 days, eosinophil counts from the resistant genotype were higher than those from their random-bred counterparts. The sheep mammary gland provides a source of eosinophils whose number is related to host genotype and stage of infection and may provide a model for the investigation of cellular responses in mucosal immunity to nematode infections.

SummarySome of the most important zoonotic infectious diseases are associated with parasites transmitted from companion animals to man. This review describes the main parasitic zoonoses in Europe related to dogs and cats, with particular emphasis on their current epidemiology. Toxoplasmosis, leishmaniosis, giardiosis, echinococcosis, dirofilariosis and toxocariosis are described from the animal, as well as from the human host perspectives, with an emphasis on parasite life cycle, transmission, pathogenicity, prevention and identification of knowledge gaps. In addition, priorities for research and intervention in order to decrease the risks and burden of these diseases are presented. Preventing zoonotic parasitic infections requires an integrated multidisciplinary ‘One Health’ approach involving collaboration between veterinary and medical scientists, policy makers and public health officials.

Promotion of animal health and well-being at the individual animal and herd level is an important goal in organic farming. At the same time, chemical products affecting the natural balance among living organisms are prohibited in all areas of the organic farm. From an animal welfare point of view, however, no animal must suffer. Therefore, veterinary drugs are allowed under the European Union's regulations for organic farming, despite the fact that they are powerful cell toxins affecting both pathogenic and necessary bacteria, and as such in organic terminology, are regarded as "chemical" or "artificial" products. In this article, we present and discuss interviews with 12 Danish organic dairy producers who claim that minimized use or nonuse of antimicrobial drugs is an explicit goal. The dairy producers were at different levels with regard to reduced antimicrobial treatment. An explicit strategy of no antimicrobial treatments is based primarily on a long-term effort to improve herd health, and secondarily, on finding alternative treatments for diseased animals. Improved hygiene, outdoor access, use of nursing cows, and blinding of chronic mastitis quarters were the main techniques in developing a strategy of not using antimicrobial treatments in the herd by dairy producers. Producers' perception of disease changed from something unavoidable to a disturbing break in the daily rhythm that often could have been avoided. Change toward a nonantimicrobial strategy was gradual and stepwise. All dairy producers in this study desired to preserve the possibility of using antimicrobial drugs in emergencies.

Paratuberculosis (Johne's disease) has been widespread in Danish dairy herds for a long time but the herd-level prevalence has never been determined precisely. To evaluate the prevalence of paratuberculosis in Danish dairy herds in various regions, an ELISA based on a commercially available antigen was adapted for testing bulk-tank milk for the presence of antibodies to Mycobacterium avium subsp. paratuberculosis. Bulk-tank milk samples were collected from six milk-collecting centres from six different areas of the country. Samples from 900 herds (about 7.5% of all Danish dairy herds) were examined, and 70% were positive at the statistically optimal cut-off (sensitivity 97.1%; specificity 83.3%). The technical performance of the ELISA was not sufficient to provide a tool for surveillance because even slight changes in optical density for the samples would change the classification of some samples. The infection is more widespread than previous investigations have shown.

Four groups of 8 parasite-naive Dorset-crossbred lambs, 3-4 months old, were turned out on infected pasture on 2 May and allocated to 4 separate paddocks. From May to September, 2 groups received Duddingtonia flagrans (10(6) chlamydospores per kg body weight per lamb per day) mixed in 100 g of barley, while the other 2 groups received barley only. All groups remained set-stocked until slaughter for worm counts on 10 October. In late June, all lambs were treated with fenbendazole due to severe parasitic gastroenteritis in all groups. The faecal egg counts were comparable for the 2 treatments throughout the grazing period. Larval development of Ostertagia/Trichostrongylus spp. in faecal cultures was 1-28% in the fungi-fed groups compared with 60-80% in the untreated groups (P < 0.05). In September, pasture larval counts of Ostertagia/Trichostrongylus were 930 and 4400 L3 kg-1 on paddocks of fungi-fed and untreated groups, respectively. Corresponding figures for Nematodirus spp. were 7200 and 11600 L3 kg-1, respectively. At slaughter, the number of immature Ostertagia spp. was 62% lower in the fungi-fed groups compared with the untreated groups (P < 0.05). Four parasite-free lambs were introduced to each paddock during the period 3-23 October and slaughtered for worm counts after 3 weeks of housing. The total worm burden of tracers on paddocks previously grazed by fungi-fed lambs was reduced 86% (P < 0.05; geometric means) compared with control groups, while significant reductions were also seen in abomasal worm counts (68%; P < 0.05), N. spathiger (98%; P < 0.05) and for N. battus (97%; P < 0.01). It is concluded that dosing sheep with D. flagrans while grazing may limit the build up of pasture contamination in the late grazing season and subsequently limit the intake of larvae in sheep.

Existing data on animal health and welfare in organic livestock production systems in the European Community countries are reviewed in the light of the demands and challenges of the recently implemented EU regulation on organic livestock production. The main conclusions and recommendations of a three-year networking project on organic livestock production are summarised and the future challenges to organic livestock production in terms of welfare and health management are discussed. The authors conclude that, whilst the available data are limited and the implementation of the EC regulation is relatively recent, there is little evidence to suggest that organic livestock management causes major threats to animal health and welfare in comparison with conventional systems. There are, however, some well-identified areas, like parasite control and balanced ration formulation, where efforts are needed to find solutions that meet with organic standard requirements and guarantee high levels of health and welfare. It is suggested that, whilst organic standards offer an implicit framework for animal health and welfare management, there is a need to solve apparent conflicts between the organic farming objectives in regard to environment, public health, farmer income and animal health and welfare. The key challenges for the future of organic livestock production in Europe are related to the feasibility of implementing improved husbandry inputs and the development of evidence-based decision support systems for health and feeding management. (HOVI, M., A. SUNDRUM and S. M. THAMSBORG (2003): Animal health and welfare in organic livestock production in Europe – current state and future challenges. Livestock production science 80, 41-53.)