The botanical, structural and chemical composition of different pelleted feeds used in a captive browsing ruminant, the moose (Alces alces)

Abstract

The commercially available, pelleted moose food sold under the same brand name (“Mazuri Moose Maintenance”) in North Amercia and Europe differs drastically in ingredient composition; the European formula does not contain the aspen sawdust that is regarded the crucial ingredient in the North American diet. Apart from these feeds, other pelleted foods designed for horses, domestic ruminants and cervids are used in feeding moose in European facilities. These pelleted feeds, and for comparison grass and browse samples, were submitted to a variety of analyses in order to isolate the potentially beneficial factors of the commercial moose feeds. All pelleted feeds had comparable particle size distributions, with the North American moose feed as the notable exception, as the sawdust particles were not as finely ground as the other ingredients. All pelleted feeds were similar in nutrient composition; however, the commercial moose feeds had higher percentages of fiber, due to a higher cellulose (and in the European pellets also hemicellulose) content. The commercial moose pellets did not display significantly higher amounts of lignin than the other pelleted feeds, in spite of the sawdust ingredient. Due to their high cellulose content, they even had lower lignin:cellulose-ratios than the other feeds and therefore rather resembled grass than browse in their fiber composition. Thus, the reported success of the commercial moose diets is most likely explained by their comparatively low energy density and high fiber content, and not by the sawdust ingredient itself. Additionally, the fact that they do not contain corn starch is considered beneficial. The nutritional contribution to husbandry problems in captive moose is considered to be generally due to the widespread use of pelleted feeds high in energy density and poor in structural fiber components.