Proficiency Testing of Feed Constituents: A Comparative Evaluation of European and Developing Country Laboratories and Its Implications for Animal Production.

Proficiency tests, with two feed samples each year, for various constituents (proximate, macro- and microminerals, feed additives, and amino acids) were conducted in 2014 and 2015. A total of 40 and 50 European and 73 and 63 developing country feed analysis laboratories participated in the study in 2014 and 2015, respectively. The data obtained from these two sets of laboratories in each year enabled a comparison of the performance of the European and developing country laboratories. Higher standard deviation and several-fold higher coefficients of variation were obtained for the developing country laboratories. The coefficients of variation for chemical composition parameters, macrominerals, microminerals, and amino acids were higher by up to 9-fold, 14-fold, 10-fold, and 14-fold, respectively, for the developing country laboratories compared with the European laboratories in 2014, while the corresponding values for 2015 were 4.6-fold, 4.4-fold, 9-fold, and 14-fold higher for developing county laboratories. Also, higher numbers of outliers were observed for developing countries (2014, 7.6-8.7% vs 2.9-3.0%; 2015, 7.7-9.5% vs 4.2-7.0%). The results suggest higher need for developing country feed analysis laboratories to improve the quality of data being generated. The likely impact of higher variability of the data generated in developing countries toward safe and quality preparation of animal diets, their impact on animal productivity, and possible ways to improve the quality of data from developing countries are discussed.