Why Some Roe Deer Develop Deformed Antlers

The French National Association of Big Game Hunters —ANCGG, by its French initials— announced on July 22, 2026, the reissue of Les têtes bizardes du chevreuil, a book by Alain François originally published in 2008. The news was later reported by Le Chasseur Français.

According to the ANCGG, the book brings together numerous field observations and photographs of abnormal roe deer antlers. Its 152 pages first examine the normal annual cycle of growth, mineralisation and casting before classifying unusual cases by their possible origin. The association cites genetic, hormonal, traumatic, nutritional, parasitic, climatic, infectious, toxic and tumoral factors.

An Unusual Shape Does Not Reveal the Cause on Its Own

This classification forms part of the book promoter’s description and does not turn every shape into a diagnosis. A twisted, asymmetrical or heavily branched antler may be the visible result of different processes. Even when the skull has been preserved, identifying the cause may require information about the animal, its body condition and previous injuries, as well as, in certain cases, a veterinary examination of tissues.

Antler biology helps explain this variety. Antlers are bony structures that periodically regenerate on the skull’s pedicles. Their development is linked to the hormonal cycle, while nutrition affects their composition and mechanical properties. A scientific review available through PubMed specifically highlights the role of nutrition and mineral availability during the formation of these structures.

Direct damage during growth may also play a part. An injury to an antler while it is still covered in velvet, or to its base, may alter its eventual shape. However, automatically attributing deformities to impacts, fights or deficiencies would oversimplify a phenomenon about which questions remain unanswered.

A Recently Described Disease

A scientific paper published in 2025 in the journal Animals provides an especially relevant warning. Its authors described a chronic inflammatory condition of the pedicle, resembling osteomyelitis, which they named Pedunculitis Chronica Deformans. The condition could impair regeneration, weaken the structure and contribute to pathological fractures or more serious infections.

The research focused primarily on fallow deer and included only five roe deer cases, alongside specimens of red deer. Its findings therefore cannot be used to extrapolate the prevalence of the disease across all populations or to explain every abnormal trophy. They do show that a deformity seemingly attributable to trauma may conceal a pathological lesion requiring more comprehensive analysis.

What It Means for Game Management

For hunters, managers and trophy assessors, these cases are of interest beyond the rarity of the trophy itself. Systematic observation of the pedicles, skull and any associated lesions may provide useful information about animal health. When several affected animals appear in the same area, documenting the findings and reporting them to veterinary or health surveillance services may help distinguish an isolated case from a problem warranting investigation.

A deformity alone does not prove that a hereditary trait is involved, nor does it justify automatic conclusions about the quality of a population. The new French reissue may serve as an informative catalogue and a starting point for recognising unusual forms, but its explanations should be read alongside the latest scientific literature. Between curiosity about an exceptional antler and a reliable diagnosis, there remains considerable scope for pathology, biology and roe deer management.