Manganese Supplementation in Deer under Balanced Diet Increases Impact Energy and Contents in Minerals of Antler Bone Tissue

Abstract

Bone ash, collagen, Ca and P composition, are considered the main factors affecting mechanical properties in bones. However, a series of studies in bone and antler have shown that some trace minerals, such as manganese, may play a role whose importance exceeds what may be expected considering their low content. A previous study showed that a reduction in manganese in antlers during a year of late winter frosts led to generalized antler breakage in Spain, which included a reduction of 30% of cortical thickness, 27% reduction in impact energy, and 10% reduction in work to peak force. Starting for this observation, we experimentally studied the effects of manganese supplementation in adults and yearling (yearlings) red deer under a balanced diet. Subjects were 29 deer of different age classes (adult n = 19, yearlings n = 10) that were divided in a manganese injected group (n = 14) and a control group (n = 15). Antler content in ashes and minerals, intrinsic mechanical properties and cross section structure were examined at 4 points along the antler beam. A one way ANOVA (mean per antler) showed that in yearlings, manganese supplementation only increased its content and that of Fe. However, in adults, Mn supplementation increased the mean content per antler of Ca, Na, P, B, Co, Cu, K, Mn, Ni, Se (while Si content was reduced), and impact work but not Young’s modulus of elasticity, bending strength or work to peak force. A GLM series on characteristics in the uppermost part examined in the antler, often showing physiological exhaustion and depletion of body stores, showed also a 16% increase in work to peak force in the antlers of the treated group. Thus, manganese supplementation altered mineral composition of antler and improved structure and some mechanical properties despite animals having a balanced diet.

Smaller does not mean worse: variation of roe deer antlers from two distant populations in their mechanical and structural properties and mineral profile

“…Specimens for mechanical testing were first subjected to a procedure to standardize humidity content as described in Cappelli et al (). This way, the bone bars had homogeneous humidity content when they were tested.…”

Does Cu supplementation affect the mechanical and structural properties and mineral content of red deer antler bone tissue?

“…This study also showed that there was a difference in Cu content between the two types of antlers assessed. Recently, Cappelli et al (2015) have shown very similar effects opposite to Mn deficiency in many antler characteristics and, again, an effect in the antler Cu content. However, no study has tried to assess the effect of supplementation with Cu injections on mechanical and structural properties and mineral composition of antler or other types of bones.…”

“…Thereafter, to standardize humidity content, the bars were dried at 20°C and 40% of relative humidity for 72 hours. The bars, that had thus homogeneous humidity content, were tested in 3-point bending with the periosteal side in tension as indicated by Cappelli et al (2015) in a Zwick/Roell 500N machine (Germany), set at 32 mm/min head speed and 40 mm gauge length.…”

“…The impact work (U) testing procedure measures the energy used to break an un-notched specimen by a pendulum falling. This energy is normalized by dividing by the cross-sectional area of the specimen (Cappelli et al, 2015). Tests were carried out in a CEAST-IMPACTOR II testing machine (CEAST S.p.A., Pianezza, Italy) with a hammer of 1J.…”

“…In order to keep that flow, blood plays an essential role delivering minerals and enzymes for antler grow, which may constitute as much as 28% of the weight of the skeleton (Gómez et al, 2012). However, in addition to Ca, other minerals such as Mn play an essential role incorporating the circulating bone Ca to the growing antlers (Landete-Castillejos et al, 2010;Cappelli et al, 2015). In spite the other minerals and the diet quality were appropriate, just the deficiency of one mineral may result in bones having a low Ca content (Strause et al, 1986).…”