The Food Deer Receive Changes Their Antlers and Reproduction: A 10-Year Study Demonstrates It

Supplementary feeding can significantly modify red deer reproduction and antler quality, according to research published in European Journal of Wildlife Research. The study analyzed ten years of data from eight red deer (Cervus elaphus) management units in Serbia’s Vojvodina province and linked the availability of natural and supplemental food with calf production, population growth and the presence of males with high-quality trophies.

The study also offers a particularly relevant conclusion for the game management of deer populations: the total amount of food supplied was not the determining factor. The type and composition of the feed were far more important.

Ten Years Tracking Deer, Food and Trophies

The research, published on 27 July 2026, was conducted by researchers from the University of Florida, the University of Novi Sad and technicians from the public forestry company Vojvodinašume, among other institutions.

The scientists analyzed eight management units over a ten-year period. Deer densities ranged from 1.6 to 14.5 animals per square kilometer, with an average of 6.2 animals/km².

Managers recorded daily the amount and type of food placed in the feeders. The foods used included alfalfa, deer-specific pellets, salt, maize cobs, maize grain, oats, turnips, wheat residues and maize silage. The feeders were designed to allow deer access, but not roe deer or wild boar.

At the same time, population censuses, checks of suckling and weaned calves, and records of hunted animals were carried out.

In males, antler quality was determined using the CIC trophy-scoring system, considering aspects such as antler weight, length and circumference, the number and development of tines, shape, symmetry and other characteristics. The trophies were classified as bronze, silver or gold.

The Key Result: It Is Not About Providing More Food

One of the most interesting conclusions for the hunting sector is that the total amount of food supplied did not emerge as a significant predictor of population performance in the main models. Instead, effects related to certain diet components and the availability of natural food did emerge.

In other words, indiscriminately increasing the amount of feed placed in a feeder does not guarantee better game-management results. The composition of that food appears to be much more important.

The authors conclude that the type of food supplied was related to three fundamental management variables: annual population growth, female reproduction and the production of males with high-quality trophies.

Turnips Are Associated with Higher Calf Production

One of the most striking results was obtained with turnips.

The amount of turnips supplied during the previous year emerged as a positive predictor of the number of weaned calves per female. It was also positively associated with the number of suckling calves observed per female.

In fact, turnip provision was a significant predictor of reproduction in 7 of the 13 models used to analyze calf production.

The researchers suggest that one possible explanation may lie in the nutritional characteristics of root crops, which are rich in fiber and potentially able to improve protein utilization by ruminants. However, they caution that the exact mechanism has not yet been fully demonstrated.

This nuance is important: the study demonstrates a statistical association, but it is not an experiment that allows us to assert that feeding turnips by itself causes a given increase in reproduction.

More Natural Food, More Chances of Producing Good Trophies

The research also gives considerable importance to the natural food available in the habitat.

The researchers used satellite imagery to calculate vegetation indices such as NDVI and EVI, which are used as indicators of plant productivity.

The results showed that greater vegetation availability during the previous year was associated both with calf production and with the presence of males with trophy-quality antlers.

Specifically, the NDVI and EVI of the previous year showed positive relationships with the production of males of hunting-quality. The models related to antler size and quality also had the greatest explanatory capacity, with R² values above 0.30.

This reinforces an idea of enormous importance for management: habitat quality may be as important as, or more important than, the artificial supply of food.

Maize Produces a Surprising Result

One of the results most likely to catch hunters’ attention involves the maize cob.

The researchers observed that management units providing smaller amounts of maize cobs had a higher proportion of males considered trophy animals.

In other words, in the data analyzed, more maize cobs did not mean better antlers. On the contrary, the statistical relationship found was negative.

The models analyzing antler quality explained approximately 32 to 33% of the variation, the highest values obtained in the study.

The authors point to metabolic problems associated with excessive cereal consumption as one possible explanation. Maize can cause acidosis in cervids, and previous research had suggested that mild metabolic acidosis could impair antler development. But once again, the current study does not experimentally demonstrate that maize is the cause of poorer antlers.

Pellets Have a Double-Edged Effect

High-protein deer pellets also produced interesting results.

Their presence was positively associated with annual population growth. However, it was simultaneously negatively related to the number of suckling calves observed alongside their mothers.

The researchers propose two possible explanations.

One is that dominant males aggressively defended feeding sites, making access more difficult for females with calves. The second possibility is that the females had genuinely had reduced access to food during the previous year, which ultimately affected their reproduction.

Therefore, nutritionally excellent food does not necessarily have a positive effect on all components of a population if the way it is distributed changes the animals’ behavior.

Density Also Matters

Feeding was not the only factor analyzed.

Deer density showed a negative relationship with annual population growth. In the units studied, the higher the density, the lower the annual growth rate tended to be.

However, density had a much weaker relationship with female reproduction. The authors believe that supplementary feeding may have partly offset the negative effects normally produced by increased competition for resources.

Here, another very interesting conclusion emerges from a game-management perspective: feeding and density cannot be managed as independent variables.

What Does This Mean for Deer Game Management?

The study has an obvious application for estates and hunting grounds where supplementary feeding is practiced.

Its results suggest that management should move away from a logic based exclusively on “more food = better deer”.

The availability of natural food, its quality, the time of year when it is available, the composition of supplementary feed and animal density all interact with one another.

For female reproduction, the period before gestation is particularly important. The study found a relationship between food availability during the previous summer and subsequent calf production.

In males, feeding during the current year is important for antler development, while nutritional conditions during the previous year also appear to be related to trophy quality. This means that the quality of a trophy is not determined solely during the weeks when the antler is growing.

An Important Warning: The Study Does Not Say What Recipe a Hunting Estate Should Use

Although the results are very interesting, the researchers themselves call for caution. The work is observational, based on ten years of records from eight management units. Therefore, it identifies relationships between variables, but does not allow us to automatically attribute a cause-and-effect relationship to each food.

In addition, the models explained approximately 16 to 33% of the variation observed in the different population parameters. A considerable part of the variation therefore remains unexplained.

Climate Change May Increase the Importance of Feeding

The study becomes even more relevant when considered in relation to the climate trends expected for Europe. Warmer and drier summers may reduce pasture productivity and the availability of natural food, especially during summer, a critical period for body condition and female reproduction.

The authors warn that this scenario could result in reduced reproduction and antler quality in the populations studied. Supplementary feeding could help compensate for part of this deficit, although it probably cannot completely replace the diversity and nutritional quality of natural food.

Scientific Reference

Wisely, S. M., Botero-Cañola, S., Prokić, V. et al. (2026). Forage availability and quality of supplemental feeding impact red deer reproduction and trophy value in Serbian red deer.European Journal of Wildlife Research, 72, 99. Published on 27 July 2026. DOI: 10.1007/s10344-026-02128-1.