Evaluation of Ultrasound Measurement of Subcutaneous Fat Thickness in Dairy Jennies during the Periparturient Period

SIMPLE SUMMARY: Ultrasonography is an accurate method to objectively measure subcutaneous fat (SF) thickness and to routinely predict body fat reserves in cows, horses, and donkeys. The aim of the present study was to describe ultrasonographic SF thickness in periparturient jennies. The SF was evaluated in 6 different truncal location in 6 dairy jennies prior and post parturition. Measurement values were reported and each site were compared through time. No statistically significant differences were found between sites and time. The mean values of SF measurements were above those reported by others. A good and reliable association was detected between body condition score (BCS) and sites during the whole study period. Our study gives a preliminary description of different body locations fat reserves evaluated by ultrasonography, showing no significative variations, in pregnant and lactating jennies. ABSTRACT: The body condition score (BCS) represents a practical but subjective method for assessing body fat reserves. Real time ultrasonography (RTU) has been proposed as an accurate method to objectively measure subcutaneous fat (SF) thickness and predict body fat reserves in cows, horses and donkeys. The aim of the present study was to describe RTU measures of SF thickness during periparturient period in jennies. The present prospective cohort study evaluated six dairy jennies. SF RTU were performed at 15 and 7 days before the presumptive delivery, and 2, 15 and 30 days after delivery. A portable ultrasound machine and multifrequency linear transducer (5–7.5 MHz) was used. RTU images were obtained in six sites (S1–S6). Results at each time point were reported as mean ± standard deviation and compared through time. A total of 180 images were evaluated. RTU technique was easy to perform and well tolerated. No statistically significant differences were found of each site during time, except for S2 and S6a: S2 at T2 and S6a at T1 were significatively different to values obtained at T5. The RTU mean values were above those reported by others, suggesting major physio-logical challenges related to energy balance and fat mobilization in pregnant jennies bred for milking production. BCS and sites through observational time have shown a good and reliable association. Our study could give preliminary indications on fat reserves in different body locations evaluated thanks to RTU and it show no significative variation of SF thickness, in pregnant and lactating jennies.