Browsing by Subject "horse"

Obesity and insulin resistance (IR) are key factors lead to equine metabolic syndrome and laminitis. Diet may play an important role in eliciting obesity by affecting insulin dynamics. Insulin-pathway signaling and mTORC1 genes may contribute to incred IR. The first objective of this study was to find and validate internal control genes for quantitative PCR method for adipose tissues in Finnhorse mares. The second aim was to quantitate the expression of mTORC1 and insulin-pathway associated genes after pasture season in two different treatment groups of Finnhorse mares and compare gene expression differences between treatment groups. In addition, gene expression differences were compared between two different adipose tissues. Twenty-two mares were equally divided into eleven equal pairs, the two mares of each group were randomly grazed either on cultivated high-yielding pasture (CG) or on semi-natural grassland (NG) from the end of May to the beginning of September. Eight pairs of Finnhorse mares were selected for gene expression profiling. Subcutaneous adipose tissue (SAT) samples were collected from two groups of Finnhorse mares after pasture season. Gene expression of neck and tailhead SAT were determined with quantitative Real-Time PCR method (qPCR). The selected internal control genes were actin beta (ACTB), glucuronidase beta (GUSB) and mitochondrial ribosomal protein L39 (MRPL39). Candidate genes were mechanistic target of rapamycin (MTOR), sterol regulatory element binding transcription factor 1 (SREBF1), sterol regulatory element binding transcription factor 2 (SREBF2), TBC1 domain family member 7 (TBC1D7), leptin (LEP), glucose transporter type 4 (GLUT4), monocyte chemoattractant protein-1 (MCP-1), retinol binding protein 4 (RBP4), tuberous sclerosis 1 (TSC1), tuberous sclerosis 2 (TSC2). There were no distinct gene expression differences between NG and CG groups in both neck and tailhead SAT. However, RBP4 had significantly (P=0.035) higher and GLUT4 had a trend (P=0.064) to higher mRNA expression in CG group in neck SAT. TSC1 had a trend (P=0.071) of higher expression in CG group in tailhead SAT. Gene expression differences were observed between tailhead and neck SAT. SREBF1 and GLUT4 had significantly (P=0.007 and P=0.026, respectively) higher expression levels in tailhead SAT compared to neck SAT. RBP4 had a trend (P=0.066) to higher expression in neck SAT compared to tailhead SAT. Minor differences in gene expression between NG and CG groups indicate that pasture-associated fat depositionmaynotconsiderably affect expressionof insulin-pathway and mTORC1 genes associated to obesity and IR in studied subcutaneous adipose tissues. These results also provide additional evidence to our hypothesis that fattening resulting on unrestricted grazing on cultivated high-yielding pasture does not increase the risk of metabolic diseases in Finnhorse mares when they have normal body condition at the beginning of the grazing season.

Good understanding of animal emotions is vital for improvement of animal welfare. Emotions are affective states that are defined by positive or negative valence depending on the pleasantness of the situation, as well as the state of arousal or excitement. As subjective experiences, emotions are hard to measure directly. Lateralization, a phenomenon in which emotion processing is done asymmetrically in different hemispheres of the brain, has been used to study changes in valence. The state of arousal is known to cause changes in the activation of the autonomic nervous system, which lead to changes in peripheral blood circulation. These neurologically mediated changes in blood flow can lead to changes in surface temperature that can be detected by infrared thermography (IRT). IRT is a technology that’s based on converting infrared radiation to images. From these images, the surface temperature of an animal can be quantitatively measured. Previous studies have focused mostly on negative emotions, which are known to affect surface temperatures. Positive and neutral affective states are in need of more research, as they have been studied less. Lateralization is also still a fairly new area of research. In this thesis I investigated if there would be detectable surface temperature patterns in riding horses at Cypis-talli, Espoo, that could be linked with mainly positive and neutral emotional states. I also explored the possibility of finding lateralization effects related to emotional states in horses. Additionally, I wanted to know if these changes in surface temperature would be situational or dependent on individual variation. We used naturally occurring situations in the horses’ lives to observe them in three situations: one where the horses got fed, one where they were taken outside to the paddocks after feeding, and one where the horses were momentarily separated from their paddocking buddies. During all situations the horses’ eyes and nasal region were measured with a thermal camera. Numerical data was collected from the images and analysed with linear mixed models and post-hoc pairwise comparisons. I found that there were significant changes in surface temperature in the eyes and nasal region of the horse that were likely related to changes in arousal. The surface temperature of the eyes and nasal region dropped when the horses got their feed, got taken outside to the paddocks and when they were separated and reunited with another familiar horse. Another finding was that there appeared to be a lateralization effect in the eyes and nasal region on the nasal cavities. There seemed to be a lot of individual variation in temperature throughout. An interesting finding was that the health condition of the horse significantly affected the temperature changes in many cases. My results suggest that surface temperature effects that have been previously seen in other species via IRT can also be detected in horses, and that the changes in temperature are most likely related to the emotional state and health status of the animal. Nasal temperature could be useful for measurement in future studies, but further research to validate its use in detection of emotional or health related states is required.

Sand enteropathy is a common form of equine colic in Finland. Detection of sand in the faeces of a horse is a widely known diagnostic method for intestinal sand accumulations. The plastic glove test is a faecal sand sedimentation test recognized by many equine practitioners. However, the diagnostic accuracy of the test is unknown, which restricts the use of the test. The main objective of this licentiate thesis was to determine the diagnostic accuracy of the plastic glove test. The most reliable diagnostic method for intestinal sand accumulations is abdominal radiography, and therefore it was used as a gold standard method against which the plastic glove test was compared. The hypothesis was that there is a positive correlation between the results of the plastic glove test and abdominal radiography. The study was conducted by collecting a faecal sample and an abdominal radiograph from each participating horse. A total of 63 faecal samples were collected from 61 different horses. All the horses were patients at the Veterinary Teaching Hospital of the Helsinki University. The cranioventral abdomen of each horse was radiographed, and the length and height of the sand accumulations were recorded. The plastic glove test was performed by mixing faecal material (~200 grams) and water (1 litre) inside a rectal sleeve. The suspension was left to hang, and the amount of sand sediment in the fingertips was recorded after 30 minutes and 24 hours. Each fingertip of the glove was assessed separately on a 0-3 numerical scale and then added up to make a total score out of 15 for each horse. The results were compared in a 2 X 2 table and ROC analysis. According to this study, the sensitivity of the plastic glove test is 82,61% (95% confidence interval 68,58% to 92,18%) and the specificity is 71,43% (95% confidence interval 41,90% to 91,61%). The positive predictive value is 90,48%, while the negative predictive value is only 55,56%. In the ROC analysis the area under the curve (AUC) is 0,771 with a 95% confidence interval of 0,644 to 0,870. The plastic glove test is a moderately accurate diagnostic test. A positive test result is usually correct, but it does not inform the severity of the condition. It can be used as an indication for further examinations or treatment. A single negative test result should not be used to exclude the disease. The plastic glove test can be a helpful tool in the diagnosis of sand enteropathy in the horse, but should not be relied on as the sole method of diagnosis due to the poor specificity of the test. Since the reference population in this study was the patient material of the Equine Hospital, more reliable results could be obtained by using a more comprehensive and randomized representation of the entire Finnish horse population. It should also be noted that 29% of the horses had been treated with psyllium and/or magnesium sulphate prior to the testing.

Tämä syventävien opintojen kirjallinen osa koostuu kolmesta osasta: kirjallisuuskatsauksesta, kokeellisesta osasta sekä tapausselostuksista. Xyloosi on pentoosi sokeri, jota käytetään arvioitaessa hiilihydraattien imeytymistä sekä ohutsuolen tilaa useilla eläinlajeilla. Hevosella ohutsuolen tutkimisen tekee erityisen hankalaksi sen vaikea saavutettavuus ja suuri tilavuus sekä pituus. Xyloosin imeytymistesti on vain yksi monista diagnostisista keinoista, joilla pyritään ymmärtämään paremmin hevosen suoliston toimintaa. Testin etu on sen tunkeutumattomuus elimistöön sekä melko edullinen hinta. Hevosella testi on standardoitu jo yli 30 vuotta sitten. Xyloosin imeytymiseen vaikuttavat useat eri tekijät: ruokavalio, paaston pituus, suolen bakteerilajisto, mahan tyhjenemisnopeus, suolen liike, munuaisten toiminta, suolen sisältö, kudosten aineenvaihdunta sekä verenkierto. Xyloosin imeytymistestin normaaliarvot, joita tutkimuksessakin käytimme ovat: 1,37mmol/l +/- 0,33 mmol/l saavutettuna 60-90 min annostelun jälkeen. Tulehduksellinen suolistosairaus, IBD, on yksi sairauksista, jonka diagnostiikassa xyloosi imeytymistestiä käytetään. Tutkimusmateriaalimme koostui kolestakymmenestäkahdesta 2-20 vuotiaasta hevosesta, jotka olivat kärsineet toistuvista ähkyistä ja/tai laihtumisesta säännöllisestä madotuksesta, hampaiden hoidosta ja riittävästä ruokinnasta huolimatta. Hevosten omistajat vastasivat kattavaan kyselyyn hevosten historiasta. Hevosille suoritettiin Yliopistollisen eläinsairaalan hevosklinikalla perusteellinen tutkimusprotokolla, joka sisälsi seuraavat tutkimukset: kliininen yleistutkimus, kuntoluokitus, ontumatutkimus (tutkimukseen ei otettu hevosia, jotka ontuivat enemmän kuin 2/5 ravissa), keuhkojen ja vatsaontelon röntgenkuvaus, suoliston ultraäänitutkimus, vatsaontelonestenäyte, ulostenäyte, virtsanäyte, perusverenkuva ja seerumista maksa, munuasivarvot, elektrolyytit sekä lihasarvot, mahantähystys, peräsuolikoepala sekä xyloosin imeytysmistesti. Kliininen tulehduksellisen suolistosairauden diagnoosi tehtiin sulkemalla muut mahdolliset vastaavien oireiden aiheuttajat sekä normaalista poikkeavien imeytymistesti tulosten, peräsuolikoepalojen ja muiden mahdollisten löydösten perusteella. Muita löydöksiä olivat tyypillisesti paksuuntunut suoli ultraäänitutkimuksessa, poikkevat valkosolu- ja fibrinogeeniarvot. Hypoteesimme oli seuraava: merkittävällä osalla hevosista, joitka kärsivät toistuvista ähkyistä tai laihtumisesta olisi epänormaali xyloosin imeytyminen. Oletimme myös, että xyloosi imeytymistesti yhdistettynä perusteelliseen suoliston tutkimukseen olisi hyvä tapa diagnostisoida tulehduksellinen suolistosairaus ilman lapratomiaa. Materiaalissamme melko monella hevosella, jotka kärsivät toistuvista ähkyistä ja/tai laihtumisesta oli epänormaali xyloosin imeytyminen (15/31). Yhdeksällä hevosella oli alentunut xyloosin imeytyminen, ja yhdeksällä viivästynyt (kolme hevosta kuului molempiin ryhmiin). Tulehduksellinen suolistosairaus varmistettiin ruumiinavauksessa kolmella hevosella, kliininen diagnoosi tehtiin kahdeksalle. Muutkin sairaudet voivat aiheuttaa epänormaalin xyloosin imeytymisen. Tällaisia ovat esimerkiksi kasvaimet, jollaisia diagnosoitiin tässä tutkimuksessa kahdella hevosella, joilla oli epänormaalin alhainen xyloosin imeytyminen. Tulehduksellinen suolistosairaus-diagnoosi perustuu pitkälti muiden syiden poissulkemiseen. Xyloosi absorptio testi ei siis ole yksinään diagnostinen taudille, mutta sitä voidaan käyttää osana laajempaa tutkimusprotokollaa tulehduksellisen suolistosairauden diagnostiikassa hevosella.