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Body Weight Estimation: Which Measurement to Use?
Abstracts Vol 29, No 5 (2009)
416
residues remaining at d 90 and 180. At d 90 pentobarbital concentrations ranged from 0.008 ppm to 0.977 ppm, and at d 180 concentrations ranged from 0.008 ppm to 3.16 ppm across all piles. Composting is a carcass disposal method that has been successfully implemented in a variety of agricultural environments. However, further research is warranted to determine if pentobarbital residue present in finished compost is acceptable to use, and is pentobarbital residue potentially harmful to people, animals, or the environment. Also, euthanasia drugs need to be studied further to determine their potential environmental effects. Further research is warranted as the number of euthanized equine carcasses disposed of via the composting process is increasing. Keywords: Compost; Drug residue; Horses; Sodium pentobarbital
measurements of body length and heart girth circumference to estimate body weight in mature horses, where estimated weight (lbs), (kg) ¼ (heartgirth2 body length)/ (330 in3), (11880 cm3).1 This formula was validated by a later group of researchers who used the same measurement techniqes.2 Recent work3-5 has suggested this formula needs to be adapted for use in young growing horses and ponies. However, there appears to be two different methods for determining body length among these studies, with one grouping defining the point of the buttock as the ischial tuberosity,1,2 and another grouping the midpoint of the distance between the widest part of the stifle and the tail.3-5 The objectives of this research were to compare estimated body weights in a group of mature horses when generated from these two different body length measurements and to see if one particular measurement was a better predictor of actual body weight.
MATERIALS AND METHODS
REFERENCES 0
1. O Rourke K. Euthanized animals can poison wildlife: Veterinarians receive fines. J Am Vet Med Assoc 2002 Jan 15. http://www.avma. org/onlnews/javma/jan02/s011502d.asp Accessed March 15, 2007.
Table 1. Approximate Pentobarbital Concentrations Pile
Liver
Day 10
Day 14
Day 90
Day 180
1 2 3 4 5 6 7 8
7.83 3.74 10.5 3.8 20.8 29.8 7.28 21.3
1.4 2.13 0.005 5.44 0.005 0.007 0.005 0.185
6.28 0.03 0.005 0.75 0.01 0.005 0.005 0.005
0.008 0.17 0.139 0.71 0.158 0.163 0.997 0.268
1.01 1.01 0.511 0.008 3.16 0.679 0.078 3.02
All Measurements are in ppm.
PRODUCTION AND MANAGEMENT - I
31854 Body Weight Estimation: Which Measurement to Use? E.L. Wagner,* P.J. Tyler, and A.M. Bruce, Auburn University, Auburn, AL, USA
INTRODUCTION The ability to accurately estimate body weight is an important tool for horse owners and caretakers when a suitable scale is not available. The formula incorporates
Thirty-five horses from the Auburn University Horse Unit were used for this pilot study. Horses consisted of 16 Quarter Horses, 1 Paint Horse, 10 Thoroughbreds and 8 warmbloods, and included 9 mares and 26 geldings. Horses ranged in age from 5 to 21 years, with a mean age of 13. They were used for teaching, research and performance activities associated with the Department of Animal Sciences. Horses were weighed on a portable livestock scale. Horses were then stood square on a flat surface for physical measurements, including height. The heart girth measurement was taken by running the measuring tape around the circumference of the horse, directly behind the shoulder and over the horse’s withers. The body length was measured twice, with both measurements originating at the point of the shoulder. The first measurement used the actual point of the buttock (ischial tuberosity) as the endpoint,2 and the second measurement used the midpoint of the distance from the widest point of the stifle to the tail.3 Two investigators performed the measurements, with each one assigned to identify specific anatomical points to ensure consistency across all animals. The same two investigators also performed independent body condition score assessments.6 All data were recorded by a separate individual, such that the measurement investigators were not aware of scale weight or each other’s BCS assessments. Estimated body weights were generated using the established formula.1 Statistical analysis consisted of paired t-tests to compare body length measurements, estimated body weights using the two different body lengths, and comparing each estimated body weight to the actual scale weight. Differences were considered significant at P < 0.05. Simple regressions were also performed to compare each estimated weight to the actual weight.
Abstracts Vol 29, No 5 (2009)
RESULTS Mean height of horses was 165.77 8.09 cm. Horses had a mean body condition score of 5 0.64. Body length measurements were significantly different, with mean values of 174.68 5.56 cm from the point of the shoulder to the ischial tuberosity, whereas the distance from the point of the shoulder to the midpoint of the distance from the stifle to tail was 164.19 5.39 cm. This resulted in a significant difference between the estimated weights (512.54 52.71 kg for stifle measurement, 545.16 54.81 kg for ischial tuberosity measurement), and both estimated weights were significantly different from the actual scale weight of 555.40 57.47 kg. When actual weight was regressed against each of the estimated weights to determine the more accurate body length measurement, the r2 values were similar (ischial tuberosity measurement, 0.85; stifle measurement, 0.87).
DISCUSSION Body length measurements differed by method and there was a subsequent difference between the resulting estimated body weights. However, both of the estimated body weights were also significantly different from the actual scale weights. This disagrees with previous work, where the estimated body weight using the formula by Hall1 was not significantly different from actual weights for mature horses.2-4 As this was a preliminary study evaluating horses at one particular farm, more horses with a wider range of body condition scores and breeds will need to be evaluated to determine which body length measurement is more accurate for use in estimating body weight. Keywords: Body weight estimation; Physical measurements REFERENCES 1. Hall LW, Wright’s Veterinary Anaesthesia and Analgesia. Londan: Baillie`re Tindall, 1971, pp. 176. 2. Carroll CL, Huntington PJ. Body condition scoring and weight estimation of horses, Equine Vet J 1998;20:41-45. 3. Wilson KR, Gibbs PG, Potter GD, Michael EM, Scott BD. Comparison of different body weight estimation methods to actual weight of horses, In: Proceedings 18th Equine Nutrition and Physiology Symposium 2003;238-242. 4. Wilson KR, Jackson SP, Abney CS, Scott BD, Gibbs PG, Eller EM. Body weight estimation methods influenced by condition score, balance and exercise status in horses, In: Proceedings 19th Equine Science Symposium 2005;57-62. 5. Owen GS, Wagner EL, Eller WS. Estimation of body weight in ponies, J Anim Sci 2008;86(E-Suppl 2):431. 6. Henneke DR, Potter GD, Kreider JL, Yeates BF. Relationship between condition score, physical measurements and body fat percentage in mares, Equine Vet J 1983;15:371-372.
ACKNOWLEDGEMENTS Special thanks to W.H. McElhenney for statistical assistance.
417
31640 Revisiting the Henneke Body Condition Scoring System: 25 Years Later R. Mottet,* G. Onan, and K. Hiney, University of Wisconsin-River Falls, River Falls, WI, USA
INTRODUCTION Body Condition Scoring is a subjective measure of adiposity in domestic livestock as well as companion animals. The body condition scoring system used in horses was created in 1985 by researchers at Texas A & M University.1 A body condition score is meant to assess subcutaneous adipose tissue accumulation and to evaluate management and feeding programs as related to energy balance.2 The system is used by veterinarians, nutritionists, farm managers and many others. The importance of this system and its use is highlighted in almost every animal science curriculum across the country. Recent research in the swine industry has indicated that subjective body condition scores (BCS) are a relatively poor basis for determining feed requirements for breeding stock and that objective ultrasonic measurements are much more precise.3 Therefore, the objective of our experiment was to explore if a similar situation exists in the equine industry. Our specific objectives were to determine the precision of subjective BCS relative to ultrasonic measurements and to determine the efficacy of BCS for reflecting changes in body fat tissue mass over time as determined by ultrasonic measurements.
MATERIALS AND METHODS This experiment used fifty-six horses that were scored for body condition and scanned at three anatomic locations; rump, rib and shoulder. The rump scan location was 5 cm off the midline with the subcutaneous fat measured at the cranial tip of the semitendinosus muscle where it overlays the gluteal muscle. The rib scan was obtained from the intercostal space between the ribs 12 & 13 with the subcutaneous fat measured over the top of the longissimus muscle at a point three-quarters of its width from its medial edge. Subcutaneous shoulder fat was measured just posterior to the caudaldorsal aspect of the scapula at the point where the trapezius overlays the latissimus. All horses were scored and scanned in late May and late August, approximately 90 days apart. Five experienced individuals (four university equine faculty members and one veterinarian in equine practice) scored the horses in May. Four of those individuals scored the horses again in August. The horses were maintained on a medium to low quality pasture throughout that period. A subset of six horses (selected from the ultrasound scans with the highest adiposity) was subjected to an exercise
416
residues remaining at d 90 and 180. At d 90 pentobarbital concentrations ranged from 0.008 ppm to 0.977 ppm, and at d 180 concentrations ranged from 0.008 ppm to 3.16 ppm across all piles. Composting is a carcass disposal method that has been successfully implemented in a variety of agricultural environments. However, further research is warranted to determine if pentobarbital residue present in finished compost is acceptable to use, and is pentobarbital residue potentially harmful to people, animals, or the environment. Also, euthanasia drugs need to be studied further to determine their potential environmental effects. Further research is warranted as the number of euthanized equine carcasses disposed of via the composting process is increasing. Keywords: Compost; Drug residue; Horses; Sodium pentobarbital
measurements of body length and heart girth circumference to estimate body weight in mature horses, where estimated weight (lbs), (kg) ¼ (heartgirth2 body length)/ (330 in3), (11880 cm3).1 This formula was validated by a later group of researchers who used the same measurement techniqes.2 Recent work3-5 has suggested this formula needs to be adapted for use in young growing horses and ponies. However, there appears to be two different methods for determining body length among these studies, with one grouping defining the point of the buttock as the ischial tuberosity,1,2 and another grouping the midpoint of the distance between the widest part of the stifle and the tail.3-5 The objectives of this research were to compare estimated body weights in a group of mature horses when generated from these two different body length measurements and to see if one particular measurement was a better predictor of actual body weight.
MATERIALS AND METHODS
REFERENCES 0
1. O Rourke K. Euthanized animals can poison wildlife: Veterinarians receive fines. J Am Vet Med Assoc 2002 Jan 15. http://www.avma. org/onlnews/javma/jan02/s011502d.asp Accessed March 15, 2007.
Table 1. Approximate Pentobarbital Concentrations Pile
Liver
Day 10
Day 14
Day 90
Day 180
1 2 3 4 5 6 7 8
7.83 3.74 10.5 3.8 20.8 29.8 7.28 21.3
1.4 2.13 0.005 5.44 0.005 0.007 0.005 0.185
6.28 0.03 0.005 0.75 0.01 0.005 0.005 0.005
0.008 0.17 0.139 0.71 0.158 0.163 0.997 0.268
1.01 1.01 0.511 0.008 3.16 0.679 0.078 3.02
All Measurements are in ppm.
PRODUCTION AND MANAGEMENT - I
31854 Body Weight Estimation: Which Measurement to Use? E.L. Wagner,* P.J. Tyler, and A.M. Bruce, Auburn University, Auburn, AL, USA
INTRODUCTION The ability to accurately estimate body weight is an important tool for horse owners and caretakers when a suitable scale is not available. The formula incorporates
Thirty-five horses from the Auburn University Horse Unit were used for this pilot study. Horses consisted of 16 Quarter Horses, 1 Paint Horse, 10 Thoroughbreds and 8 warmbloods, and included 9 mares and 26 geldings. Horses ranged in age from 5 to 21 years, with a mean age of 13. They were used for teaching, research and performance activities associated with the Department of Animal Sciences. Horses were weighed on a portable livestock scale. Horses were then stood square on a flat surface for physical measurements, including height. The heart girth measurement was taken by running the measuring tape around the circumference of the horse, directly behind the shoulder and over the horse’s withers. The body length was measured twice, with both measurements originating at the point of the shoulder. The first measurement used the actual point of the buttock (ischial tuberosity) as the endpoint,2 and the second measurement used the midpoint of the distance from the widest point of the stifle to the tail.3 Two investigators performed the measurements, with each one assigned to identify specific anatomical points to ensure consistency across all animals. The same two investigators also performed independent body condition score assessments.6 All data were recorded by a separate individual, such that the measurement investigators were not aware of scale weight or each other’s BCS assessments. Estimated body weights were generated using the established formula.1 Statistical analysis consisted of paired t-tests to compare body length measurements, estimated body weights using the two different body lengths, and comparing each estimated body weight to the actual scale weight. Differences were considered significant at P < 0.05. Simple regressions were also performed to compare each estimated weight to the actual weight.
Abstracts Vol 29, No 5 (2009)
RESULTS Mean height of horses was 165.77 8.09 cm. Horses had a mean body condition score of 5 0.64. Body length measurements were significantly different, with mean values of 174.68 5.56 cm from the point of the shoulder to the ischial tuberosity, whereas the distance from the point of the shoulder to the midpoint of the distance from the stifle to tail was 164.19 5.39 cm. This resulted in a significant difference between the estimated weights (512.54 52.71 kg for stifle measurement, 545.16 54.81 kg for ischial tuberosity measurement), and both estimated weights were significantly different from the actual scale weight of 555.40 57.47 kg. When actual weight was regressed against each of the estimated weights to determine the more accurate body length measurement, the r2 values were similar (ischial tuberosity measurement, 0.85; stifle measurement, 0.87).
DISCUSSION Body length measurements differed by method and there was a subsequent difference between the resulting estimated body weights. However, both of the estimated body weights were also significantly different from the actual scale weights. This disagrees with previous work, where the estimated body weight using the formula by Hall1 was not significantly different from actual weights for mature horses.2-4 As this was a preliminary study evaluating horses at one particular farm, more horses with a wider range of body condition scores and breeds will need to be evaluated to determine which body length measurement is more accurate for use in estimating body weight. Keywords: Body weight estimation; Physical measurements REFERENCES 1. Hall LW, Wright’s Veterinary Anaesthesia and Analgesia. Londan: Baillie`re Tindall, 1971, pp. 176. 2. Carroll CL, Huntington PJ. Body condition scoring and weight estimation of horses, Equine Vet J 1998;20:41-45. 3. Wilson KR, Gibbs PG, Potter GD, Michael EM, Scott BD. Comparison of different body weight estimation methods to actual weight of horses, In: Proceedings 18th Equine Nutrition and Physiology Symposium 2003;238-242. 4. Wilson KR, Jackson SP, Abney CS, Scott BD, Gibbs PG, Eller EM. Body weight estimation methods influenced by condition score, balance and exercise status in horses, In: Proceedings 19th Equine Science Symposium 2005;57-62. 5. Owen GS, Wagner EL, Eller WS. Estimation of body weight in ponies, J Anim Sci 2008;86(E-Suppl 2):431. 6. Henneke DR, Potter GD, Kreider JL, Yeates BF. Relationship between condition score, physical measurements and body fat percentage in mares, Equine Vet J 1983;15:371-372.
ACKNOWLEDGEMENTS Special thanks to W.H. McElhenney for statistical assistance.
417
31640 Revisiting the Henneke Body Condition Scoring System: 25 Years Later R. Mottet,* G. Onan, and K. Hiney, University of Wisconsin-River Falls, River Falls, WI, USA
INTRODUCTION Body Condition Scoring is a subjective measure of adiposity in domestic livestock as well as companion animals. The body condition scoring system used in horses was created in 1985 by researchers at Texas A & M University.1 A body condition score is meant to assess subcutaneous adipose tissue accumulation and to evaluate management and feeding programs as related to energy balance.2 The system is used by veterinarians, nutritionists, farm managers and many others. The importance of this system and its use is highlighted in almost every animal science curriculum across the country. Recent research in the swine industry has indicated that subjective body condition scores (BCS) are a relatively poor basis for determining feed requirements for breeding stock and that objective ultrasonic measurements are much more precise.3 Therefore, the objective of our experiment was to explore if a similar situation exists in the equine industry. Our specific objectives were to determine the precision of subjective BCS relative to ultrasonic measurements and to determine the efficacy of BCS for reflecting changes in body fat tissue mass over time as determined by ultrasonic measurements.
MATERIALS AND METHODS This experiment used fifty-six horses that were scored for body condition and scanned at three anatomic locations; rump, rib and shoulder. The rump scan location was 5 cm off the midline with the subcutaneous fat measured at the cranial tip of the semitendinosus muscle where it overlays the gluteal muscle. The rib scan was obtained from the intercostal space between the ribs 12 & 13 with the subcutaneous fat measured over the top of the longissimus muscle at a point three-quarters of its width from its medial edge. Subcutaneous shoulder fat was measured just posterior to the caudaldorsal aspect of the scapula at the point where the trapezius overlays the latissimus. All horses were scored and scanned in late May and late August, approximately 90 days apart. Five experienced individuals (four university equine faculty members and one veterinarian in equine practice) scored the horses in May. Four of those individuals scored the horses again in August. The horses were maintained on a medium to low quality pasture throughout that period. A subset of six horses (selected from the ultrasound scans with the highest adiposity) was subjected to an exercise