Pia Haubro Andersen

An equine pain face.

Objective The objective of this study was to investigate the existence of an equine pain face and to describe this in detail. Study design Semi-randomized, controlled, crossover trial. Animals Six adult horses. Methods Pain was induced with two noxious stimuli, a tourniquet on the antebrachium and topical application of capsaicin. All horses participated in two control trials and received both noxious stimuli twice, once with and once without an observer present. During all sessions their pain state was scored. The horses were filmed and the close-up video recordings of the faces were analysed for alterations in behaviour and facial expressions. Still images from the trials were evaluated for the presence of each of the specific pain face features identified from the video analysis. Results Both noxious challenges were effective in producing a pain response resulting in significantly increased pain scores. Alterations in facial expressions were observed in all horses during all noxious stimulations. The number of pain face features present on the still images from the noxious challenges were significantly higher than for the control trial (p = 0.0001). Facial expressions representative for control and pain trials were condensed into explanatory illustrations. During pain sessions with an observer present, the horses increased their contact-seeking behavior. Conclusions and clinical relevance An equine pain face comprising ‘low’ and/or ‘asymmetrical’ ears, an angled appearance of the eyes, a withdrawn and/or tense stare, mediolaterally dilated nostrils and tension of the lips, chin and certain facial muscles can be recognized in horses during induced acute pain. This description of an equine pain face may be useful for improving tools for pain recognition in horses with mild to moderate pain.

Indicators of induced subacute ruminal acidosis (SARA) in Danish Holstein cows.

BackgroundThe prevalence of subacute ruminal acidosis (SARA) in dairy cows is high with large impact on economy and welfare. Its current field diagnosis is based on point ruminal pH measurements by oral probe or rumenocentesis. These techniques are invasive and inaccurate, and better markers for the diagnosis of SARA are needed. The goal of this study was to evaluate clinical signs of SARA and to investigate the use of blood, faecal and urinary parameters as indicators of SARA. Six lactating, rumen cannulated, Danish Holstein cows were used in a cross-over study with three periods. The first and second periods included two cows on control diet and two cows on nutritional SARA challenge. The third period only included two cows on SARA challenge. Control diet was a conventional total mixed ration [45.5% dry matter (DM), 17.8% crude protein, 43.8% neutral detergent fibre, and 22.5% acid detergent fibre (DM basis)]. SARA challenge was conducted by substituting control diet with grain pellets (50% wheat/barley) over 3xa0days to reach 40% grain in the diet. Ruminal pH was measured continuously. Blood samples were collected once daily at 7xa0h after feeding. Samples of faeces and urine were collected at feeding, and at 7 and 12xa0h after feeding. Blood samples were analysed for pCO2, pO2, pH, electrolytes, lactate, glucose, packed cell volume (PCV), and total plasma protein concentration. Milk composition, ruminal VFA, and pH of faeces and urine were measured.ResultsSARA was associated with decreased (Pxa0<xa00.05) minimum ruminal, faecal and urinary pH. Daily times and areas of ruminal pH below 5.8, and 5.6 were increased to levels representative for SARA. Significant differences were detected in milk composition and ruminal VFAs. Blood calcium concentration was decreased (Pxa0<xa00.05), and pCO2 tended to be increased (Pxa0=xa00.10). Significant differences were not detected in other parameters.ConclusionsSARA challenge was associated with changes in faecal and urinary pH, blood calcium concentration and pCO2. These may be helpful as indicators of SARA. However changes were small, and diurnal variations were present. None of these parameters are able to stand alone as indicators of SARA.

Changes in Microbiota in Rumen Digesta and Feces Due to a Grain-Based Subacute Ruminal Acidosis (SARA) Challenge

The effects of a grain-based subacute ruminal acidosis (SARA) challenge on bacteria in the rumen and feces of lactating dairy cows were determined. Six lactating, rumen-cannulated Danish Holstein cows were used in a cross-over study with two periods. Periods included two cows on a control diet and two cows on a SARA challenge. The control diet was a total mixed ration containing 45.5% dry matter (DM), 43.8% DM neutral detergent fiber, and 19.6% DM starch. The SARA challenge was conducted by gradually substituting the control diet with pellets containing 50% wheat and 50% barley over 3xa0days to reach a diet containing 55.6% DM, 31.3% DM neutral detergent fiber, and 31.8% DM starch, which was fed for four more days. Rumen fluid samples were collected at day 7 and 10 of experimental periods. Feces samples were collected on days 8 and 10 of these periods. Extracted DNA from the rumen and feces samples was analyzed to assess their bacterial communities using MiSeq Illumina sequencing of the V4 region of the 16S rRNA gene. The induction of SARA reduced the richness, diversity, and stability of bacterial communities and resulted in distinctly different microbiota in the rumen and feces. Bacteroidetes and Firmicutes were the most abundant phyla and, combined, they represented 76.9 and 94.4% of the bacterial community in the rumen fluid and the feces, respectively. Only the relative abundance of Firmicutes in the rumen was increased by the SARA challenge. In rumen fluid and feces, the abundances of nine out of the 90 and 25 out of the 89 taxa, respectively, were affected by the challenge. Hence, SARAxa0challenge altered the composition of the bacterial community at the lower taxonomical level in the feces and therefore also likely in the hindgut, as well as in the rumen. However, only reductions in the bacterial richness and diversity in the rumen fluid and feces were in agreement with those of other studies and had a biological basis. Although the composition of the bacterial community of the feces was affected by the SARA challenge, bacterial taxa in the feces that can be used for accurate and non-invasive diagnosis of SARA could not be identified.

Handheld mechanical nociceptive threshold testing in dairy cows – intra-individual variation, inter-observer agreement and variation over time

Objective To examine the use of handheld methodology to assess mechanical nociceptive threshold (MNT) on cows kept loose-housed. Study design Prospective randomized partial cross-over experimental study. A one-factor (test day) design was used to evaluate MNT over time. Animals One hundred and fifteen healthy, loose-housed Danish Holstein cattle. Methods We evaluated intra-individual variation, inter-observer agreement and variation over time of MNT using two handheld devices and two stimulation sites. Mechanical, ramped stimulations were performed with an algometer (6.5 mm diameter steel probe, 0–10.0 kgf) or an electronic von Frey device (plastic tip with diameter 0.8 mm, 0–1000 gf). Each cow received 5–6 consecutive stimulations within a 2 × 5 cm skin area on the dorsal or lateral aspect of the left third metatarsus until an avoidance reaction occurred. We investigated the difference in precision [expressed as coefficient of variation (CV)] between the combinations of devices and stimulation sites. The inter-observer agreement and the difference in MNT between test day 1, 3, 7, 10 and 24 were investigated for selected combinations. Data were analysed in mixed models and Bland-Altman as relevant. Results The CVs did not differ [range 0.34–0.52 (p = 0.1)]. Difference between observers (95% limits) was 0.2 kgf (2.8) and 4 gf (369) for the algometer and von Frey device, respectively. Mechanical nociceptive threshold increased from 361 on test day one to 495 gf on test day 24 (p < 0.01). Conclusion and clinical relevance All methods showed a high degree of intra-individual variation, and no combination of device and stimulation site showed superior precision. Mean difference between observers was low, and MNT was not consistent over time. Further development of the methods is required before they can be used in research to investigate possible relations between claw lesions and hyperalgesia.

Equine deep stromal abscesses (51 cases - 2004-2009)--Part 1: the clinical aspects with attention to the duration of the corneal disease, treatment history, clinical appearance, and microbiology results.

OBJECTIVEnTo study the equine deep stromal abscesses (DSA) with focus on the duration of the corneal disease, medical treatment, season of presentation, clinical appearance, and the degree of corneal vascularization.nnnMATERIAL AND METHODSnEquine DSA diagnosed, biopsied, and surgically treated at the University of Florida Veterinary Medical Center (UFVMC) from 2004 to 2009 were identified. The medical record, clinical photographic images, and microbiology results for each case were evaluated. Frequency and prevalence calculation as well as qualitative data analysis was performed for clinical and microbiological data.nnnRESULTSnFifty-one equine DSA were included in the study. Spring (March, April, May; 33.4%) and winter (December, January, February; 31.4%) were the most common seasons for DSA presentation. The 51 cases were divided into four categories of focal opacity from their clinical appearance: focal yellow (45.2%), focal white (23.5%), diffuse yellow/white (23.5%), and focal pink (7.8%). 5.9% of the DSA (n = 3) were culture positive for fungal growth, whereas 17.6% were positive for bacterial growth (n = 9). No association between short-/long-term systemically administered NSAID treatment and the corneal vascular response to the corneal lesion could be appreciated.nnnCONCLUSIONnEquine DSA most often present in the spring and winter in the subtropical environment of the state of Florida (USA). The clinical appearance may have a connection with the etiology and pathogenesis of the equine DSA. No connection between short- or long-term systemically administered NSAID and the degree of corneal vascularization of the DSA was noted.

Accuracy and precision of oscillometric blood pressure in standing conscious horses

BACKGROUNDnArterial blood pressure (BP) is a relevant clinical parameter that can be measured in standing conscious horses to assess tissue perfusion or pain. However, there are no validated oscillometric noninvasive blood pressure (NIBP) devices for use in horses.nnnANIMALSnSeven healthy horses from a teaching and research herd.nnnHYPOTHESIS/OBJECTIVEnTo evaluate the accuracy and precision of systolic arterial pressure (SAP), diastolic arterial pressure (DAP), and mean arterial pressure (MAP) in conscious horses obtained with an oscillometric NIBP device when compared to invasively measured arterial BP.nnnMETHODSnAn arterial catheter was placed in the facial or transverse facial artery and connected to a pressure transducer. A cuff for NIBP was placed around the tail base. The BP was recorded during normotension, dobutamine-induced hypertension, and subnormal BP induced by acepromazine administration. Agreement analysis with replicate measures was utilized to calculate bias (accuracy) and standard deviation (SD) of bias (precision).nnnRESULTSnA total of 252 pairs of invasive arterial BP and NIBP measurements were analyzed. Compared to the direct BP measures, the NIBP MAP had an accuracy of -4 mm Hg and precision of 10 mm Hg. SAP had an accuracy of -8 mm Hg and a precision of 17 mm Hg and DAP had an accuracy of -7 mm Hg and a precision of 14 mm Hg.nnnCONCLUSIONS AND CLINICAL RELEVANCEnMAP from the evaluated NIBP monitor is accurate and precise in the adult horse across a range of BP, with higher variability during subnormal BP. MAP but not SAP or DAP can be used for clinical decision making in the conscious horse.

Dynamic expression of leukocyte innate immune genes in whole blood from horses with lipopolysaccharide-induced acute systemic inflammation

BackgroundIn horses, insights into the innate immune processes in acute systemic inflammation are limited even though these processes may be highly important for future diagnostic and therapeutic advances in high-mortality disease conditions as the systemic inflammatory response syndrome (SIRS) and sepsis. Therefore, the aim of this study was to investigate the expression of 31 selected blood leukocyte immune genes in an equine model of acute systemic inflammation to identify significantly regulated genes and to describe their expression dynamics during a 24-h experimental period. Systemic inflammation was induced in 6 adult horses by the intravenous injection of 1xa0μg lipopolysaccharide (LPS) per kg btw. Sixteen blood samples were collected for each horse at predetermined intervals and analyzed by reverse transcription quantitative real-time PCR. Post-induction expression levels for each gene were compared with baseline levels.ResultsSystemic inflammation was confirmed by the presence of clinical and hematological changes which were consistent with SIRS. The clinical response to LPS was transient and brief as all horses except one showed unaltered general demeanor after 24xa0h. Twenty-two leukocyte genes were significantly regulated at at least one time point during the experimental period. By close inspection of the temporal responses the dynamic changes in mRNA abundance revealed a very rapid onset of both pro- and anti-inflammatory mediators and a substantial variation in both expression magnitudes and duration of changes between genes. A majority of the 22 significantly regulated genes peaked within the first 8xa0h after induction, and an on-going, albeit tightly controlled, regulation was seen after 24xa0h despite approximate clinical recovery.ConclusionsThis first broad study of gene expressions in blood leukocytes during equine acute LPS-induced systemic inflammation thoroughly characterized a highly regulated and dynamic innate immune response. These results provide new insights into the molecular mechanisms of equine systemic inflammation.

Equine deep stromal abscesses (51 cases - 2004-2009)--Part 2: the histopathology and immunohistochemical aspect with attention to the histopathologic diagnosis, vascular response, and infectious agents.

PURPOSEnTo investigate histopathologic and immunohistochemical aspects of equine deep stromal abscesses (DSA) with a focus on the histopathologic diagnosis, presumptive etiology, and the immunohistochemical expression of three angiogenesis-related factors: vascular endothelial growth factor-A (VEGF-A), pigment epithelium-derived factor (PEDF), and interleukin-1 receptor antagonist (IL-1ra).nnnSAMPLE POPULATIONnParaffin-embedded biopsy samples from 51 DSA. The biopsies were collected from full-thickness penetrating keratoplasty or split-thickness lamellar keratoplasty surgeries at the University of Florida Veterinary Medical Center in the period from 2004 to 2009.nnnPROCEDUREnThe histopathologic and immunohistochemical findings were tested for association between each other. Prevalence calculation and test for association with qualitative data analysis was used for data evaluation.nnnRESULTSnFungal hyphae were found histologically in 47.1% (n = 24) of the DSA cases. Histopathologically, most fungal DSA showed suppurative keratitis (n = 34; 66.7%) and little to no stromal vascularization infiltrating the abscess (negative association, P = 0.005). All three angiogenesis-related factors were expressed to some degree in DSA tissue. A negative association between VEGF-A and PEDF when compared to the presence of fungal hyphae (P < 0.001, P = 0.023) indicated that cases positive for these two factors will most probably not have fungal hyphae present.nnnCONCLUSIONnAbnormally decreased VEGF-A expression is suggested as the reason for the slow vascularization and delayed resolution of fungal DSA, whereas PEDF and IL-ra did not seem to have any influence on the vascularization process. Clinical and histopathologic characteristics of DSA make it possible to suggest an etiology for an equine DSA with an unknown etiology.

Monitoring of equine health in Denmark: The importance, purpose, research areas and content of a future database

The plentiful data on Danish horses are currently neither organized nor easily accessible, impeding register-based epidemiological studies on Danish horses. A common database could be beneficial. In principle, databases can contain a wealth of information, but no single database can serve every purpose. Hence the establishment of a Danish equine health database should be preceded by careful consideration of its purpose and content, and stakeholder attitudes should be investigated. The objectives of the present study were to identify stakeholder attitudes to the importance, purpose, research areas and content of a health database for horses in Denmark. A cross-sectional study was conducted with 13 horse-related stakeholder groups in Denmark. The groups surveyed included equine veterinarians, researchers, veterinary students, representatives from animal welfare organizations, horse owners, trainers, farriers, authority representatives, ordinary citizens, and representatives from laboratories, insurance companies, medical equipment companies and pharmaceutical companies. Supplementary attitudes were inferred from qualitative responses. The overall response rate for all stakeholder groups was 45%. Stakeholder group-specific response rates were 27-80%. Sixty-eight percent of questionnaire respondents thought a national equine health database was important. Most respondents wanted the database to contribute to improved horse health and welfare, to be used for research into durability and disease heritability, and to serve as a basis for health declarations for individual horses. The generally preferred purpose of the database was thus that it should focus on horse health and welfare rather than on performance or food safety, and that it should be able to function both at a population and an individual horse level. In conclusion, there is a positive attitude to the establishment of a health database for Danish horses. These results could enrich further reflection on the establishment of a Danish equine health database and prove useful to institutions abroad considering establishing similar databases.

Acute-phase proteins as diagnostic markers in horses with colic.

OBJECTIVEnTo investigate the diagnostic potential of the concentrations of acute-phase proteins serum amyloid A (SAA), haptoglobin (Hp), and fibrinogen in blood and peritoneal fluid (PF) for differentiating horses with inflammatory colic (entero-colitis and peritonitis) from those with surgical colic.nnnDESIGNnProspective observational multicenter study.nnnSETTINGnTwo university referral hospitals.nnnANIMALSnHorses referred for severe acute abdominal pain to Hospital 1 (nxa0=xa0148) or Hospital 2 (nxa0=xa078).nnnINTERVENTIONnBlood and PF samples collected at admission were used for acute-phase protein concentration measurement.nnnMEASUREMENTS AND MAIN RESULTSnA multivariable logistic model including clinical parameters (lethargy, rectal temperature >38°C [100.4°F], normal rectal examination findings, and gastric reflux of 5-10xa0L) recorded at admission was constructed from Hospital 1 data. The ability of the model to correctly differentiate inflammatory from surgical colic was 86% determined as area under the receiver operating characteristic curve. Adding blood parameters (WBC, PCV, total plasma protein, lactate, SAA, Hp, and fibrinogen concentrations) to the logistic model based on clinical parameters revealed that only WBC and SAA and fibrinogen concentrations improved the model. With SAA included in the model no additional blood parameters improved the model, and the final model had an area under the curve of 90%. Addition of PF parameters (hemolysis, total protein concentration, WBC, SAA, or Hp concentrations) did not improve the model. When validated in Hospital 2 data, the models had good integrity and diagnostic performance.nnnCONCLUSIONSnEvaluation of SAA in serum improved the ability to differentiate horses with acute inflammatory colic requiring medical treatment from horses with colic requiring surgery, as it allowed an additional 4% of horses to be correctly classified into medical and surgical cases. Improved differentiation of these 2 groups of horses with colic may minimize the risk of unnecessary or delayed surgery.