Evaluation of a microwave method for dry matter detemination in faecal samples from weaned pigs with or without clinical diarrhoea

TY - JOUR

T1 - Evaluation of a microwave method for dry matter detemination in faecal samples from weaned pigs with or without clinical diarrhoea

AU - Pedersen, Ken Steen

AU - Stege, Helle

AU - Nielsen, Jens Peter

PY - 2011/7/1

Y1 - 2011/7/1

N2 - Microwave drying as a procedure for determination of faecal dry matter in weaned pigs was evaluated and clinical relevant cut-off values between faecal consistency scores were determined.Repeatability and reproducibility were evaluated. Overall coefficient of variation was 0.03. The 95% confidence limits for any future faecal subsample examined by any operator in any replica were ±0.85% faecal dry matter.Robustness in relation to weight of wet faeces was evaluated. The weight categories were 0.5, 1.0, 1.5, 2.0 and 3.0. g. Samples of 0.5. g gave significantly different mean faecal dry matter content compared to weighing of 1.0-3.0. g.Agreement with freeze-drying was evaluated. Lin's concordance correlation coefficient was 0.94. On average the faecal dry matter values was 1.7% (SD = 1.99%) higher in freeze dried compared to micro waved samples.Non-parametric ROC analyses were used to determine optimal faecal dry matter cut-off values for clinical faecal consistency scores. The 4 consistency scores were score 1 = firm and shaped, score 2 = soft and shaped, score 3 = loose and score 4 = watery. The cut-off values were score 1: faecal dry matter content >19.5%, score 2: faecal dry matter content ≤19.5% and >18.0%, score 3: faecal dry matter content ≤18.0% and >11.3%, score 4: faecal dry matter content ≤11.3%.In conclusion, the microwave procedure has an acceptable repeatability/reproducibility and good agreement with freeze drying can be expected. A minimum of 1.0. g of wet faeces must be used for analyses. Faecal dry matter cut-off values between 4 different clinical consistency scores were determined.

AB - Microwave drying as a procedure for determination of faecal dry matter in weaned pigs was evaluated and clinical relevant cut-off values between faecal consistency scores were determined.Repeatability and reproducibility were evaluated. Overall coefficient of variation was 0.03. The 95% confidence limits for any future faecal subsample examined by any operator in any replica were ±0.85% faecal dry matter.Robustness in relation to weight of wet faeces was evaluated. The weight categories were 0.5, 1.0, 1.5, 2.0 and 3.0. g. Samples of 0.5. g gave significantly different mean faecal dry matter content compared to weighing of 1.0-3.0. g.Agreement with freeze-drying was evaluated. Lin's concordance correlation coefficient was 0.94. On average the faecal dry matter values was 1.7% (SD = 1.99%) higher in freeze dried compared to micro waved samples.Non-parametric ROC analyses were used to determine optimal faecal dry matter cut-off values for clinical faecal consistency scores. The 4 consistency scores were score 1 = firm and shaped, score 2 = soft and shaped, score 3 = loose and score 4 = watery. The cut-off values were score 1: faecal dry matter content >19.5%, score 2: faecal dry matter content ≤19.5% and >18.0%, score 3: faecal dry matter content ≤18.0% and >11.3%, score 4: faecal dry matter content ≤11.3%.In conclusion, the microwave procedure has an acceptable repeatability/reproducibility and good agreement with freeze drying can be expected. A minimum of 1.0. g of wet faeces must be used for analyses. Faecal dry matter cut-off values between 4 different clinical consistency scores were determined.

U2 - 10.1016/j.prevetmed.2011.04.014

DO - 10.1016/j.prevetmed.2011.04.014

M3 - Journal article

C2 - 21571379

SN - 0167-5877

VL - 100

SP - 163

EP - 170

JO - Preventive Veterinary Medicine

JF - Preventive Veterinary Medicine

IS - 3-4

ER -