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Query: UMLS:C0017160 (gastroenteritis)
 11,398 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Comparative analyses of the patterns of gastrointestinal nematode infections of first-grazing season cattle in Belgium are presented. The analysis involves 17 studies covering a 10 year period on 13 different farms in Flanders, Belgium. In all studies the calves were divided into an untreated control group, and one or two groups treated with chemoprophylactic systems. Two general infection levels emerged-'sub-clinical' (14 studies) and 'clinical' (three studies). The 'sub-clinical' infections were characterised by no clinical signs of parasitic gastroenteritis in the untreated control groups. Mean faecal egg counts remained low (less than 200), maximum pepsinogen levels only reached about 3500 mU tyrosine, and very small reductions in overall daily weight gain were observed compared with calves given chemoprophylaxis (less than 40 g day-1). Based on these results, on these 'sub-clinical' farms, chemoprophylaxis may not have been needed. In contrast, multiple salvage treatments of the control calf groups were required in the 'clinical' infections. Even with these salvage treatments mean faecal egg counts were high (more than 300), maximum pepsinogen levels were over 5500 mU tyrosine and there was a very large reduction in overall daily weight gain (more than 300 g day-1). However, it was not possible to predict either at turnout, or during the first month afterwards whether an infection on a particular farm would develop into a 'clinical' infestation. With the present data this prediction was possible from 8 weeks (Day 56) onwards, based on faecal egg counts and pasture larval contamination. It was also possible to predict using serum pepsinogen levels on Day 84. Therefore, one possible strategy for the effective control of gastrointestinal nematode infections of calves in temperate regions would be to evaluate faecal egg counts 2 months after turnout, and then only start treatment (i.e. metaphylaxis) if required.
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PMID:Gastrointestinal nematode infections of first-season grazing calves in Belgium: general patterns and the effect of chemoprophylaxis. 918 35

The efficacy of a move to aftermath in July combined with moxidectin or fenbendazole treatment for the control of parasitic gastroenteritis (PGE) in calves was evaluated in three field experiments in the Netherlands. In all five treated groups high gastrointestinal nematode infections and PGE were prevented by a dose and move in July. Cooperia infections increased to moderate levels in two groups treated with moxidectin and one group treated with fenbendazole. In both other groups and also for Ostertagia in these three groups, low to extremely low infections were acquired. In the first experiment high primary infections, resulting in high faecal egg counts and a moderate increase of blood pepsinogen values occurred before the dose and move. Nevertheless, these primary infections were not high enough to result in PGE. In both other experiments primary infection levels were low and faecal egg counts increased to 100-650 eggs/g faeces at the end of the grazing season. The blood pepsinogen values of non-treated control groups demonstrated that it took more than a month after their move to aftermath before substantial reinfection occurred on the new pasture. In the first and the last experiment only, high Ostertagia and Cooperia infections developed in the control group at the end of the grazing season, though it did not result in clinical PGE. The experiments demonstrate all theoretical risks of the dose and move system: (1) PGE early in the grazing season as a result of high overwintered pasture infectivity. (2) PGE just before the move as a result of an early midsummer increase in pasture infectivity. (3) PGE around housing as a result of insufficient suppression of pasture infectivity late in the grazing season. (4) Underexposure to nematode infections due to a high suppression of nematode infections. Nevertheless, it can be concluded that under normal conditions the dose and move system remains to be a valuable and easily applicable system for the control of PGE.
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PMID:The efficacy of Michel's dose and move system on gastrointestinal nematode infections in diary calves. 963 14

The build up of gastrointestinal nematode infections was followed in two grazing experiments. Both experiments included four groups of six calves, a permanently housed non-infected control group and three groups which were grazed from May to October. One of these was moved to aftermath in the beginning of July, the second in the beginning of July and August and the third in the beginning of July, August and September. The build up of gastrointestinal nematode infections was followed by performing faecal egg counts, differentiation of faecal larval cultures, pasture larval counts, serum pepsinogen values, serum antibodies against Cooperia oncophora, weight gain and worm counts. In the second experiment four of the principal trial animals of each group were treated with oxfendazole and subsequently challenged with 100,000 larvae of Ostertagia ostertagi to examine development of immunity against O. ostertagi. The faecal egg counts and the worm counts of the sentinels necropsied in July indicated low initial infections in both experiments. Infection levels in experiment 1 remained low in each group until the beginning of September. However, during the last month, moderate to high infections were acquired by the groups which were moved once or twice. In contrast, low to moderate infections were maintained in the group moved three times. In the second experiment moderate C. oncophora burdens were already observed in the sentinels grazed until the beginning of August. Tracers grazing in August-September with the group moved once acquired high O. ostertagi and C. oncophora infections, whereas those grazed with both other groups acquired moderate infections. In October high infections with both species occurred in the groups moved once and twice, whereas low to moderate infections were observed in the group moved three times. The challenge infection demonstrated a reduction of establishment of O. ostertagi of approximately 70% in all three groups on pasture. The results demonstrate that moving calves at monthly intervals to clean pasture can be an effective method for the control of parasitic gastroenteritis. In addition, the data indicate that it is essential that the last move does not occur more than 1 month before the end of the grazing season.
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PMID:The effect of repeated moves to clean pasture on the build up of gastrointestinal nematode infections in calves. 965 93

A field study was conducted between May and October 1995 to examine the efficacy of 0.5 mg/kg ivermectin pour-on on parasitic gastroenteritis of set-stocked calves at turnout and 6 weeks later. A treated group of 10 calves was compared with a separately grazed group of 10 non-treated calves; 14 calves were used as tracer animals. Initial infection levels appeared to be very low in both groups and faecal egg counts, pasture larval counts, serum pepsinogen levels and optical density (OD) values of an ELISA with a specific recombinant antigen for Cooperia oncophora remained low for 4 months. Thereafter, a rapid build up of gastrointestinal nematode infections occurred in both groups.
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PMID:Evaluation of the effect of ivermectin administered topically at zero and six weeks after turnout on gastrointestinal nematode infection in first-season grazing cattle. 978 28

A two-year study was conducted in northern Germany to investigate the effects of the fenbendazole slow release (SR) bolus on trichostrongyle infections in cattle. Two groups of dairy replacement calves were either given a bolus at their first turncut on pasture or treated with fenbendazole suspension twice in mid-summer and at housing. Bolus-treated and control animals were set stocked on separate pastures during their first grazing season (26 weeks) and grazed together during the second year (24 weeks). During the first season the bolus prevented substantially the output of strongyle eggs for more than four months resulting in a lower infection risk in late summer and autumn as compared to the control group. The plasma pepsinogen concentrations remained low in the bolus-treated cattle during their first grazing period but rose in the controls soon after turnout which indicated increasing trichostrongyle-caused damages of the abomasal mucosa. During the following housing period and the second grazing season the bolus-treated animals showed higher egg counts than the controls. No clinical sign of parasitic gastroenteritis and no patent lungworm infections were observed during the study. The bolus-treated cattle performed better than the control animals during both grazing seasons although the control group had compensated temporarily the group difference in weight gains during the housing period. In conclusion, the use of the fenbendazole SR bolus may impair the development of immunity to trichostrongyle infections to some extent but, under the present conditions, this does not seem of clinical or economic importance.
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PMID:[Effects of the fenbendazole SR bolus on Trichostrongylus infections in young calves during two consecutive grazing periods]. 1022 Sep 45

The effect of strategic treatments with ivermectin in first-season calves exposed to trichostrongyle nematodes on naturally contaminated pasture was studied. Twenty first season heifer calves were divided into 2 groups, according to live weight, and on 22nd May each group was turned out onto a 1 hectare pasture. Group A (Plot A) was treated with ivermectin at weeks 3, 8 and 13 after turn out, while group B (Plot B) served as an untreated control group. The study showed that control calves exhibited increase in trichostrongyle egg counts in August, while treated calves were excreting low numbers of trichostrongyle eggs. Pasture larval counts on Plot B (control animals) were low during the first part of the grazing season, followed by a steep rise towards the end of July. In contrast, the numbers of infective larvae recovered from Plot A remained low throughout the season. Both groups showed comparable weight gains from May up to the middle of July. However, from then on, Group B (controls) had lower weight gains than ivermectin treated Group A. From the end of July onwards, most untreated calves (Group B) showed clinical signs of parasitic gastroenteritis. It can be concluded that the strategical ivermectin treatments were successful, and faecal egg counts, pepsinogen levels and herbage larval counts clearly demonstrated that this was accomplished through suppression of pasture contamination with nematode eggs and subsequent reduction of pasture infectivity.
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PMID:Effect of strategic treatments with invermectin on parasitism of set-stocked calves exposed to natural trichostrongyle infection in Lithuania. 1060 32

The influence of gastrointestinal nematode infections on performance of four groups of female Holstein Friesian calves was monitored until the end of the second grazing season (SGS). In the first year three groups were grazed and one group (G4) was permanently housed. General and grazing management during the first grazing season (FGS) was arranged such that G1 acquired moderate infections, G2 low infections and G3 very low infections with gastrointestinal nematodes. These infections were monitored through faecal egg counts, differentiation of faecal larval cultures, pasture larval counts, serum pepsinogen values, ELISA with a recombinant Cooperia oncophora protein, weight gain, tracer worm counts and sentinel worm counts. In 1998 all four groups were grazed together as one herd from 23 April to 26 October and infections were monitored with the same techniques with the exception of sentinel calves. In the FGS weight gain was higher in G4 than in the other groups and higher in G3 (28. 6kg) than in G1. Weight gain of G2 was intermediate to G1 and G3 but did not significantly differ from either group. In the SGS weight gain in G4 was far less than in any other group and the mean weight at the end of the experiment was 41.9, 38.6 and 50.9kg lower than G3, G1 and G2, respectively. Though no significant differences were observed between G1, G2 and G3 at the end of the experiment it was obvious that the weight gain advantage of G3 over G1 at the end of the FGS had disappeared. Parasitological and serological findings in the SGS indicated that G3 and G4 had build up less immunity during the FGS compared to G1 and G2. The conclusion of the experiment is that resilience to parasitic gastroenteritis in the SGS depends on the level of exposure to nematodes in the FGS. However, problems with poor weight gain only will be expected when exposure is very low in the FGS and high in the SGS.
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PMID:Resilience of second year grazing cattle to parasitic gastroenteritis following negligible to moderate exposure to gastrointestinal nematode infections in their first year. 1072 44

In this paper the different options for the diagnosis of gastrointestinal nematode infections are discussed. Diagnostic tests have a role in confirming the clinical diagnosis of parasitic gastroenteritis, but are more important for herd health monitoring of nematode infections, in particular for cattle. Therefore, emphasis is placed on discussing the available diagnostic parameters on their usefulness for that purpose. For clinical diagnosis the clinical signs, combined with the history of the animals is usually sufficient and a laboratory confirmation is not required. Faecal egg counts are, with two exceptions, not suitable for confirmation of the clinical diagnosis, because correlation between faecal egg counts and infection levels is usually low. These exceptions are the diagnosis of haemonchosis in small ruminants and the detection of anthelmintic resistance. This also limits the value of DNA-based tests of faecal material; even quantitative tests of nematode species specific DNA will have little value for diagnosis and monitoring. Pasture larval counts and worm counts are useful parameters for basic epidemiological studies on nematode infections. However, they are too laborious to be used for either routine diagnosis or monitoring. Blood parameters, such as gastrin and pepsinogen and serology are valuable tools for diagnosis. Pepsinogen and ELISAs based on recombinant proteins show most promise as parameters for herd health monitoring. However, extensive epidemiological studies are still needed before these parameters can be implemented in routine herd health monitoring schemes for parasitic gastroenteritis.
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PMID:Value of present diagnostic methods for gastrointestinal nematode infections in ruminants. 1087 14

The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bimonthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March-June and October-December) and lowest during the dry seasons (July-September and January-February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.
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PMID:The epidemiology of gastrointestinal nematodes of dairy cattle in central Kenya. 1136 Jul 97

Twenty-five, castrated male Holstein-cross calves, between 4 and 5 months of age, weighing 156.5+/-12.2 kg and reared under conditions designed to minimise the risk of parasitic infection, were allocated to one of the five treatment groups on the basis of initial bodyweight. The groups were (1) ad libitum (ad lib) fed controls (ALC); (2) ad lib fed infected (INF) and treated with topical eprinomectin on Day 56; (3) controls pair-fed with the INF group (PFC); (4) ad lib fed controls treated with eprinomectin on Days 0 and 56 (E-ALC) and (5) ad lib fed, infected and treated with eprinomectin on Days 0 and 56 (E-INF). Infection comprised a trickle infection with the equivalent of 10,000 larvae of Ostertagia ostertagi per day from Day 0 to Day 56 and the study concluded on Day 77. Parameters measured throughout the study included: liveweight, feed intake, faecal egg counts; plasma pepsinogen, gastrin, ghrelin and leptin; plasma antibodies to adult O. ostertagi. No significant differences in feed intake or liveweight gain were observed between any of the different groups, a finding thought to result from the high quality of feed offered. Significant differences between the INF and control groups however were observed in faecal egg counts, plasma pepsinogen, gastrin and O. ostertagi antibodies, which were all elevated, and leptin, which was reduced. Values of these parameters for the E-INF group were intermediate between the INF and ALC groups. Plasma ghrelin showed no association with either feed intake or parasitism. Further studies are needed to fully elucidate the roles of various biochemical and neuroendocrine mediators for inappetence in ruminants with parasitic gastroenteritis.
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PMID:Associations between blood gastrin, ghrelin, leptin, pepsinogen and Ostertagia ostertagi antibody concentrations and voluntary feed intake in calves exposed to a trickle infection with O. ostertagi. 1934 78


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