MEASUREMENT OF BODY COMPOSITION IN CATS USING COMPUTED TOMOGRAPHY AND DUAL ENERGY X‐RAY ABSORPTIOMETRY

Dual energy X‐ray absorptiometry (DEXA) is a reference method for assessing body composition but is seldom `accessible in veterinary settings. Computed tomography (CT) can provide similar body composition estimates and we propose that it can be used in body composition studies in animals. We compared CT and DEXA data from 73 healthy adult neutered domestic cats. Three approaches for measuring adipose tissue percentage from full‐body CT scans were explored. By examining the frequency distribution of voxels by Hounsfield unit (HU) value, it is possible to calculate a fat index (Fat%) that is in close agreement with the fat percentages obtained from DEXA scans. Fat% values obtained by the best of the methods had a mean difference of 0.96% (95% confidence interval 0.33–1.59%) from the DEXA results. Fat% obtained by the other two methods were characterized by good correlation but poor agreement and in one of the methods, the difference between the values from the two modalities was proportional to their mean. By using CT, it is possible to obtain body composition estimates that are in close agreement with those available using DEXA. While the significance of individual Fat% measurements obtained from CT can be difficult to interpret and to compare between centers, CT can contribute to research studies concerned either with nutrition or with obesity‐related disorders.     

The effect of sugar beet pulp-based silage additives on effluent production, fermentation, in-silo losses, silage intake and animal performance

First-harvest direct-cut, double-chopped grass (190 and 164g DMkg^?1 in Experiments 1 and 2 resptectively) was ensiled without an additive or, in Experiment 1, with 30 kg t^?1 grass of an absorbent additive based on sugar beet pulp (Sweet ‘n’ Dry) or with 3·441 t^?1 grass of formic acid and, in Experiment 2, with 30, 50 and 70 kg t^?1 grass of Sweet ‘n’ Dry or with 50kg t^?1 grass of unmolassed sugar beet pulp. The preservation and nutritive value of the silage, in-silo losses (including silage effluent production), silage intake and animal performance of adult and growing cattle were examined. In Experiment 1 all three silages were well preserved, although the formic acid-treated silage displayed significantly lower pH, ammonia nitrogen (NH₃N) [g kg^?1 total nitrogen (TN)] and volatile fatty acids (VFAs) than the other two silages. In Experiment 2 absorbent-treated silages displayed significantly lower pH, buffer capacity (Bc), NH₃N (gkg^?1 TN), CP, modified acid detergent fibre (MADF) and VFAs than untreated silage. Treatment of grass with the absorbent additives at ensiling resulted in reduced effluent production. In Experiment 1 each kilogram of Sweet ‘n’ Dry retained approximately 11 effluent, and in Experiment 2 silages made with Sweet ‘n’ Dry applied at 70kgt^?1 and sugar beet pulp applied at 50 kg t^?1 produced similar volumes of effluent and each kilogram of absorbent retained 1·0 and 1·31 of effluent respectively. In Experiment 1 sixty beef cattle [mean initial live weight (LW) 460 kg] were grouped according to LW and allocated to treatment at random. For untreated silage (unsupplemented or with 1 or 2 kg supplement head^?1 day^?1), absorbent-treated silage (unsupplemented or with 1 or 2 kg supplement head^?1 day^?1) and formic acid-treated silage (1 kg supplement head^?1 day^?1) the daily silage DM intakes were 6·12, 6·21, 6·40, 7·65, 7·45, 7·11 and 7·85 (s.e. 0·280) kg respectively, the daily liveweight gains were 0·22, 0·56, 0·81, 0·59, 0·74, 0·81 and 0·75 (s.e. 0·071) kg respectively and daily carcass gains were 0·31, 0·47, 0·67, 0·47, 0·61, 0·70 and 0·57 (s.e. 0·043) kg respectively throughout a 75-day feeding period. In Experiment 2, fifty-six growing cattle (mean initial weight 312 kg) were grouped according to LW and allocated to treatment at random. For untreated silage (unsupplemented or with 1·5 kg Sweet ‘n’ Dry or 1·5 kg commercial concentrates head^?1 day^?1), silage treated with Sweet ‘n’ Dry at 30, 50 and 70 kg t^?1 grass and silage treated with 50kg sugar beet pulp t^?1 grass the daily silage DM intakes were 5·46, 5·28, 5·33, 6·21, 6·27, 6·60 and 6·62 (s.e. 0·154) kg respectively and daily liveweight gains were 0·39, 0·75, 0·81, 0·63, 0·76, 0·94 and 1·75 (s.e. 0·052) kg respectively throughout a 122-day feeding period. In this experiment 360g kg^?1 more absorbent was required when it was included at ensiling rather than offered as a supplement to untreated silage to achieve the same individual animal performance.     

IMAGING DIAGNOSIS—CONGENITAL VENOUS ANEURYSM OF THE LEFT EXTERNAL JUGULAR VEIN

Primary congenital jugular vein aneurysms are rare with only one prior report in a canine patient. Herein, we describe an 18-week-old Flat Coated Retriever dog in which ultrasound was used to diagnose a primary congenital external jugular vein aneurysm with concurrent dilatation of the internal jugular vein. The aneurysm was successfully removed and the dog remains disease free 24 months postoperatively. Histopathologic analysis was used to validate the ultrasound-based diagnosis.     

ULTRASOUND IMAGE COMPOUNDING: EFFECT ON PERCEIVED IMAGE QUALITY

In order to determine the effect of different image compounding functions on perceived image quality, 84 pairs of ultrasound images were collected, mixed, and reviewed by four independent observers who were asked to identify the highest quality image of each pair. Each image in a pair was made using the same orientation, transducer, frequency, and gain settings but different compounding settings. Outcomes were analyzed using logistic regression. Observers judged compound images to be better quality than noncompound images in 69% cases, the same quality in 24%, and poorer quality in 7%. Overall, compound images were considered significantly better quality than noncompound images (P < 0.001). Compound images were more likely to be considered better quality than the corresponding noncompound images when combined transmit/receive spatial compounding was used rather than receive-only spatial compounding or transmit compounding, and when the vector transducer or the curvilinear transducer were used rather than the linear transducer. Observers considered improved border definition and increased signal to noise ratio to be the properties that accounted most often for higher quality of compound images compared with noncompound images.     

Surgical Treatment of Sand Colic Results in 40 Horses

A retrospective study of 40 horses that underwent surgical treatment for sand colic was performed. Three horses were euthanatized and one died during surgery. Of the 36 horses that recovered from anesthesia, five died before discharge from the hospital and seven died after discharge. Twenty-four horses survived at least 12 months. Sand impaction of the right dorsal colon was present in 26 horses. In addition to sand impaction, 10 horses also had colonic displacement or volvulus.