Abstract: In equids, health and welfare depend on body composition. A growing number of equids are now used as leisure and companion animals, and often found overfeed. The need for a close monitoring of body fatness led to the search for tools allowing a rapid and non-invasive estimation of fatness. This study intends to assess real-time ultrasonography (RTU) usefulness in establishing a relationship between ultrasound measures of subcutaneous fat-plus-skin thickness (SF-Skin) and body condition score (BCS) in horses and donkeys. Forty-three healthy animals (16 donkeys and 27 horses) were used in this study to generate 95 records (RTU and BCS pairs), in multiple RTU sessions for 2 years. Using visual appraisal and palpation, BCS was graded in a 1-9 points scale. Real-time ultrasonography images were taken using a 7.5 MHz linear transducer, placed perpendicular to the backbone, over the 3rd lumbar vertebra. ImageJ was used to measure the SF-Skin on RTU images. The relation between BCS and SF-Skin measurements was tested by linear and polynomial regression analysis. Results: The BCS values were similar in horses (5.50; from 3 to 8 points) and donkeys (5.14; from 3 to 7 points). The SF-Skin measures show a similar trend (a mean of 7.1 and 7.7 mm in horses and donkeys, respectively). A polynomial regression among BCS and SF-Skin explained 92 and 77 % of the variation in donkeys and horses respectively. The coefficient of determination was considerably higher for the regression developed for donkeys compared with that of horses (R2 = 0.92 vs. 0.77, respectively), which reduced the accuracy of the method in horses. Both the linear and polynomial models tested show a strong relationship among BCS and SF-Skin for donkeys (R2 > 0.91; P < 0.01) and horses (R2 > 0.74; P < 0.01), despite that the extremes for BCS did not existed in our sample. Conclusions: Our results showed the potential RTU usefulness to monitor body fat in equids. Using a high-frequency transducer and RTU together with image analysis allowed the identification of small SF-skin variations. This report will support further studies on the relationships between SF-Skin and BCS, particularly in extreme BCS scores.
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The research article investigates the potential use of real-time ultrasonography (RTU) in estimating the body fat of equids (horses and donkeys), by establishing a relationship between ultrasound measurements of subcutaneous fat and skin thickness, and the traditional body condition score.
Study Goal and Methodology
The main objective of this study was to evaluate the usefulness of real-time ultrasonography (RTU) in determining the relation between ultrasound measurements of subcutaneous fat-plus-skin thickness (SF-Skin) and the body condition score (BCS) in horses and donkeys.
43 healthy animals, consisting of 16 donkeys and 27 horses, were used to gather 95 records in multiple RTU sessions over a period of 2 years.
The BCS was evaluated based on visual assessment and palpation, on a scale of 1 to 9. Ultrasound images were captured with a 7.5 MHz linear transducer, positioned perpendicular to the backbone, over the 3rd lumbar vertebra.
A software called ImageJ was used to measure SF-Skin from the ultrasound images, with the results assessed through linear and polynomial regression analysis.
Study Results
The study found that BCS values were fairly similar among both animas – with an average of 5.50 among horses and 5.14 among donkeys.
Measurements of SF-Skin exhibited a similar trend, with averages of 7.1 and 7.7 mm in horses and donkeys respectively.
The regression analysis showed a strong relationship between BCS and SF-Skin, explaining 92% of the variation in donkeys and 77% in horses. The accuracy of this method was found to be higher in donkeys compared to horses.
Despite the absence of extreme BCS scores in the sample, both linear and polynomial models showed a significant relationship between BCS and SF-Skin in both horses (R2 > 0.74; P < 0.01) and donkeys (R2 > 0.91; P < 0.01).
Study Conclusion
The researchers concluded that real-time ultrasonography (RTU), when used in conjunction with high-frequency transducer and image analysis, has the potential to effectively monitor body fat in equids through tracking small changes in SF-Skin.
The findings of this study will support ongoing research into the relationships between SF-Skin and BCS, particularly in equids with extreme BCS scores.
Cite This Article
APA
Silva SR, Payan-Carreira R, Quaresma M, Guedes CM, Santos AS.
(2016).
Relationships between body condition score and ultrasound skin-associated subcutaneous fat depth in equids.
Acta Vet Scand, 58(Suppl 1), 62.
https://doi.org/10.1186/s13028-016-0243-2
CECAV-Centro de Ciência Animal e Veterinária, Universidade de Trás-os-Montes e Alto Douro, Quinta de Prados, 5000-801, Vila Real, Portugal.
Payan-Carreira, Rita
CECAV-Centro de Ciência Animal e Veterinária, Universidade de Trás-os-Montes e Alto Douro, Quinta de Prados, 5000-801, Vila Real, Portugal. rtpayan@gmail.com.
Quaresma, Miguel
CECAV-Centro de Ciência Animal e Veterinária, Universidade de Trás-os-Montes e Alto Douro, Quinta de Prados, 5000-801, Vila Real, Portugal.
Guedes, Cristina M
CECAV-Centro de Ciência Animal e Veterinária, Universidade de Trás-os-Montes e Alto Douro, Quinta de Prados, 5000-801, Vila Real, Portugal.
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