2 research outputs found
Mykotoxiner och deras effekt pÄ hÀstens hÀlsa
Abstract
Mycotoxins are secondary metabolites produced by filamentous fungi. Moulds producing mycotoxins grow on various crops that are used as horse feeds. Since the treatments of mycotoxin poisoned horses are limited it is important to prevent production of mycotoxins in feed. The major mycotoxin producing moulds in horse feeds are Fusarium spp., Penicillium spp. and Aspergillus spp. Other moulds are also of concern in horse feeds. Claviceps purpurea (ergot) have been known for centuries to cause disease in both humans and animals. The mould Rhizoctonia leguminicola which can produce the mycotoxin slaframine grow on legumes and can therefore be of concern in forages. The most important mycotoxins in horse feeds are fumonisin, trichotecenes, aflatoxin, ochratoxin A, ergot alkaloids and slaframine. Zearalenone may have an impact on horse health, but it is still not completely investigated. Horses are the species most sensitive to fumonisins and the mechanisms of intoxication in horses is therefore well studied. Horses poisoned by mycotoxins show various signs from vague such as loss of appetite or depression to acute such as convulsions and sudden death. This review gives a brief summary of the most important mycotoxins known to affect horsesâ health and the most common symptoms of poisoning.
Sammanfattning
Mykotoxiner Ă€r sekundĂ€ra metaboliter som bildas av filamentösa svampar. Mykotoxinproducerande mögelarter kan tillvĂ€xa i mĂ„nga olika grödor som senare blir hĂ€stfoder. Eftersom möjligheten att behandla mykotoxinförgiftade hĂ€star Ă€r mycket begrĂ€nsad Ă€r det viktigt att arbeta förebyggande för att motverka mykotoxinbildning i foder. De vanligast förekommande mykotoxinproducerande mögelarterna i hĂ€stfoder Ă€r Fusarium spp., Penicillium spp. och Aspergillus spp. men Ă€ven andra mögelarter Ă€r viktiga att ta hĂ€nsyn till. Claviceps purpurea eller âmjöldrygaâ Ă€r kĂ€nd sedan Ă„rhundraden tillbaka för att orsaka sjukdom hos bĂ„de djur och mĂ€nniskor. Mögelarten Rhizoctonia leguminicola kan producera mykotoxinet slaframin och vĂ€xer pĂ„ baljvĂ€xter som exempelvis rödklöver och kan dĂ€rmed utgöra en risk i vallfoder. De mykotoxiner som Ă€r viktigast att ha kunskap om nĂ€r man utfodrar hĂ€star Ă€r fumonisiner, trichotecener, aflatoxin, ochratoxin A, ergotalkaloider och slaframin. Zearalenon kan ha betydelse för hĂ€stens hĂ€lsa, men hur Ă€r Ă€nnu inte helt klarlagt. HĂ€star Ă€r de djur som Ă€r mest kĂ€nsliga för fumonisiner och det Ă€r dĂ€rför vĂ€l studerat hur hĂ€star pĂ„verkas av dessa. Mykotoxinförgiftning kan ge allt frĂ„n diffusa symptom som aptitförlust och depression till mer akuta som kramper och plötslig död. Detta arbete ger en kort genomgĂ„ng av de viktigaste mykotoxinerna som i dagslĂ€get Ă€r kĂ€nda för att pĂ„verka hĂ€stars hĂ€lsa samt de vanligaste symptomen pĂ„ förgiftning
Possibilities to make temperament assessment of horses at Young Horse Test
Den hĂ€r studien utfördes under treĂ„rstest pĂ„ fyra platser 2011 i Sverige och totalt ingick 315 hĂ€star. Syftet var att undersöka möjligheter att sĂ„ objektivt som möjligt bedöma unghĂ€stars temperament i samband med redan befintligt treĂ„rstest. Detta eftersom det finns en önskan att fler temperamentsegenskaper införs i avelsvĂ€rderingen. Det gjordes en etologisk studie av beteendet vid uppstĂ€llning för exteriörbedömning och betygsupplĂ€sning dĂ€r alla avvikelser frĂ„n stillastĂ„ende pĂ„ hĂ€stens egna initiativ registrerades. Ăgare eller utbildare av de hĂ€star som observerades ombads fylla i en enkĂ€t dĂ€r de skulle göra en bedömning av flera olika temperamentsegenskaper. Syftet med enkĂ€ten var att se om en objektiv bedömning under testet kunde stĂ€mma med hur hĂ€stens temperament uppfattades av Ă€garen/utbildaren. Under studiens gĂ„ng utarbetades en mall för att beskriva hĂ€starnas temperament och beteende under hela testet (TB). TB bestod av sex olika punkter dĂ€r temperamentsegenskaper beskrevs utifrĂ„n en linjĂ€r modell.
Sambanden mellan de olika resultaten frÄn studien studerades med Spearman rangkorrelationer och ett antal olika signifikanta korrelationer kunde ses. Korrelationerna mellan enkÀtsvar frÄn Àgare/utbildare och olika punkter i TB visade pÄ att en hÀst som blev nervös nÀr den isolerades frÄn andra hÀstar eller en mer flyktbenÀgen hÀst brÄkade mer vid uppstÀllning. En mer flyktbenÀgen hÀst var Àven mindre samarbetsvillig nÀr den visades vid hand. Mellan enkÀtsvaren och resultaten frÄn den etologiska studien fanns endast ett samband som visade pÄ att en hÀst som blev nervös nÀr den isolerades frÄn andra hÀstar rörde mer pÄ sig vid exteriörbedömningen. Det fanns flera samband mellan de enskilda punkterna i TB och den etologiska studien dÀr högst korrelation var till punkten som beskrev hÀstens beteende vid exteriörbedömningen.
Mellan betyget hÀstarna fick av domarna pÄ treÄrstestet och temperamentsfrÄgorna i enkÀten fanns lÄga korrelationer. En mer förutsÀgbar hÀst fick ett nÄgot högre betyg pÄ skritten och en mindre flyktbenÀgen hÀst fick ett lite högre temperamentsbetyg i löshoppning av domarna. Mellan TB och hoppbetygen kunde nÄgra korrelationer ses, de starkaste innebar att en hÀst med mer framÄtbjudning i löshoppning fick ett lite högre betyg för temperament och allmÀnt intryck i löshoppning samt för teknik och förmÄga. Ett annat samband innebar att en mer samarbetsvillig hÀst fick ett högre hoppbetyg av domarna. Det fanns nÄgra lÄga korrelationer mellan TB och gÄngartsbetygen; en mer samarbetsvillig hÀst fick ett högre betyg för skritt, en hÀst som var spÀnd i början av testet fick ett nÄgot högre betyg pÄ traven och en hÀst som visade mer framÄtbjudning i lösgalopp eller löshoppning fick ett nÄgot högre betyg pÄ galoppen.
Slutsatsen blev att det Àr möjligt att beskriva en del av hÀstarnas temperamentsegenskaper utifrÄn deras beteende vid treÄrstestet men det behövs ytterligare studier för att sÀkerstÀlla vilka egenskaper som Àr relevanta att beskriva.This study was performed during the young horse tests at four locations in 2011 in Sweden and included a total of 315 horses. The aim was to explore possibilities to assess the young horses' temperament as objectively as possible in already existing young horse tests. The study was initiated because there is a desire to include more temperamental characteristics in the genetic evaluation. In an ethological study of the behavior at standing still for conformation assessment all deviations from standing still on the horses own initiatives were recorded. The owner or trainer of the horses that were observed were asked to fill out a questionnaire in which they would make an assessment of several different temperament characteristics. The purpose of the survey was to see if an objective assessment during the test was consistent with how the horse's temperament was perceived by the owner/trainer. During the study a protocol to describe the horses' temperament and behavior throughout the test was developed (TB). TB consisted of six different parts where temperament characteristics were described based on a linear model. The relationships between the various study results were studied with Spearman rank correlations and a number of significant correlations were seen. The correlations between survey responses from the owners/trainers and various parts of TB showed that a horse who was nervous when it was isolated from other horses or a more flighty horse was less cooperative more when it should stand still. A more flighty horse was also less cooperative when it was shown at hand. There was only one significant correlation between survey responses and results of the ethological study and it showed that a horse that was nervous when it was isolated from other horses moved more at the exterior assessment. There were several correlations between the individual parts in TB and the ethological study where the strongest correlation was to the part that described the behavior of the horse at the exterior assessment. There were some low correlations between grades horses got by the judges on the young horse test and temperament questions in the survey. A more predictable horse received a slightly higher grade for walk and a less flighty horse got a little higher temperament grade in free jumping by the judges. Between TB and jumping grades there were some correlations, the strongest meant that a horse with more willingness to go forward in free jumping got a bit higher grades for temperament and overall impression in the free jumping as well as for technique and ability. A more cooperative horse also got a higher jumping grade by the judges. There were some low correlations between TB and gaits; a more cooperative horse got a higher grade for walk, a horse that was tense at the beginning of the test, received a slightly higher grade for trot and a horse that showed more willingness to go forward in free canter or free jumping got a slightly higher grade for free canter. It was concluded that it is possible to describe some of the horses' temperament characteristics in terms of their behavior at the young horse test but further studies are needed to determine which characteristics are relevant to describe