Roe deer (
The parasite has been found in roe deer for many years not only in Poland but also in other countries, and its prevalence has been seen to depend mainly on the local population density (3, 22, 23, 28). In 2012, an infestation by the larvae of this fly was diagnosed for the first time in two male roe deer in Extremadura in Spain, which is the southern most region of occurrence of this parasite (6). However, the research in this field is still insufficient, and there are no detailed data on the presence of the parasite in Poland or other European countries.
Due to the habitat and climate diversity of different regions of Poland, roe deer are characterised by high variability in their carcass weight and/or antler weight and form. Roe deer from the Lublin region have substantially higher carcass and antler weight than those from other areas in Poland (12, 14, 32, 34). The presence of
The study was based on post-mortem analysis of the occurrence of
The skin, muscles, and connective tissue as well as the eyes and brain were removed from the animal’s head, which ensured access to all potential locations of the parasitic larvae (Fig. 1). During these procedures, the throat and oesophagus were assessed as well. Where
Older animals were found to be infested by clearly the largest number of parasitic larvae (Table 1). In 2- and 3-year-old individuals, from 1.6 to 4 parasites were found on average, with the maximum being 7. The mean number of parasites in older bucks increased with age, and the highest number (n = 14) was found in 5-year-old animals from grassland habitats. Animals culled in field ecosystems were infested by the highest number of larvae, followed by individuals from grassland habitats, and in those from forest ecosystems the lowest number of larvae was found. The parasite prevalence varied depending on the animal habitat. The lowest infestation prevalence of 18% was determined in bucks from forest ecosystems, whereas the highest level of 48% was detected in animals culled in grassland habitats. Overall and not differentiating by age or habitat, parasite prevalence was estimated at 33%.
Number of confirmed
Age | Habitat (ecosystem) |
|||
---|---|---|---|---|
Agro | Grassland | Forest | ||
n (%) | 5 (33.3) | 3 (21.4) | 1 (7.1) | |
mean | 1.6 | 1.7 | 1 | |
2 | min | 1.0 | 1.0 | 1 |
max | 2.0 | 3.0 | 1 | |
n (%) | 4 (36.3) | 6 (50.0) | 3 (27.3) | |
mean | 4.0 | 3.5 | 2.3 | |
3 | min | 2.0 | 1.0 | 1.0 |
max | 7.0 | 7.0 | 3.0 | |
n (%) | 1 (10.0) | 8 (61.5) | 2 (20.0) | |
mean | 1 | 5.9 | 4.5 | |
4 | min | 1 | 2.0 | 4.0 |
max | 1 | 12.0 | 5.0 | |
n (%) | 3 (27.3) | 4 (40.0) | 3 (30.0) | |
mean | 7.0 | 6.3 | 3.3 | |
5 | min | 5.0 | 2.0 | 2.0 |
max | 11.0 | 14.0 | 5.0 | |
n (%) | 7 (53.8) | 8 (72.7) | 2 (16.7) | |
mean | 6.0 | 4.0 | 2.5 | |
≥6 | min | 2.0 | 1.0 | 2.0 |
max | 12.0 | 7.0 | 3.0 |
The mean carcass weights of the culled bucks varied with the animal’s age. In almost all cases, infested animal carcasses weighed less (Table 2). Statistically significant differences between the carcass weights of infested and non-infested animals were found in the group of 6-year-old and older bucks from agroecosystems. The mean difference amounted to 2.65 kg. Similar differences were also found in the group of 4-year-old animals from grassland habitats and forest ecosystems. When the bucks were not stratified by age, there were statistically significant differences between the infested and non-infested only in animals from agroecosystems.
Male roe deer carcass weight presented habitat and presence of
Habitat (ecosystem) | Item | Age (years) |
Total/Mean | |||||
---|---|---|---|---|---|---|---|---|
2 | 3 | 4 | 5 | ≥6 | ||||
Non-infested | n | 10 | 7 | 9 | 8 | 6 | 40 | |
mean | 15.85 | 17.92a | 19.22 | 20.18a | 21.00a | 18.61a | ||
Infested | n | 5 | 4 | 1 | 3 | 7 | 20 | |
Agro | mean | 14.40 | 15.87b | 17.62 | 18.16b | 18.35b | 16.88b | |
Mean | 15.37x | 17.18 | 18.87xy | 19.64x | 19.57 | 18.02x | ||
SEM | 0.92 | 0.69 | 1.24 | 1.06 | 1.41 | 1.12 | ||
Non-infested | n | 11 | 6 | 5 | 6 | 3 | 31 | |
mean | 14.63 | 17.75a | 20.40a | 20.16a | 20.00a | 17.75 | ||
Infested | n | 3 | 6 | 8 | 4 | 8 | 29 | |
Grassland | ||||||||
mean | 15.00 | 15.91b | 17.12b | 18.25b | 18.50b | 17.18 | ||
Mean | 14.71xy | 16.82 | 18.38x | 19.40x | 18.91 | 17.48xy | ||
SEM | 0.73 | 0.89 | 0.92 | 0.86 | 0.72 | 0.27 | ||
Non-infested | n | 13 | 8 | 8 | 7 | 10 | 46 | |
mean | 14.23 | 16.81a | 18.25a | 18.00 | 18.95 | 16.97 | ||
Infested | n | 1 | 3 | 2 | 3 | 2 | 11 | |
Forest | ||||||||
mean | 13.84 | 15.66b | 16.75b | 17.16 | 19.00 | 16.48 | ||
Mean | 14.22y | 16.50 | 17.9550y | 17.75y | 18.96 | 16.86y | ||
SEM | 0.65 | 0.87 | 0.53 | 0.81 | 1.42 | 2.10 |
SEM – standard error of the mean; a, b – mean values of carcass weight of infested and non-infested individuals within an ecosystem marked with different letters differ significantly at P ≤ 0.05; x, y– mean values of carcass weight of individuals from different ecosystems marked with different letters differ significantly at P ≤ 0.05
The infestation by the
Gross antler weight of male roe deer presented by habitat and presence of
Habitat (ecosystem) | Item | Age (years) |
Total/Mean | |||||
---|---|---|---|---|---|---|---|---|
2 | 3 | 4 | 5 | ≥6 | ||||
Non-infested | n | 10 | 7 | 9 | 8 | 6 | 40 | |
mean | 189.20a | 287.42 | 401.33a | 419.25 | 419.16 | 334.62 | ||
Infested | n | 5 | 4 | 1 | 3 | 7 | 20 | |
Agro | mean | 121.20b | 238.75 | 331.12b | 368.33 | 388.14 | 283.31 | |
Mean | 166.53x | 269.73 | 394.31x | 405.36 | 402.46 | 318.10 | ||
SEM | 20.54 | 16.25 | 31.24 | 25.44 | 17.14 | 18.12 | ||
Non-infested | n | 11 | 6 | 5 | 6 | 3 | 31 | |
mean | 163.27 | 294.66a | 404.60a | 421.33a | 480.00a | 308.22 | ||
Grassland | Infested | n | 3 | 6 | 8 | 4 | 8 | 29 |
mean | 155.00 | 223.66b | 323.00b | 327.50b | 398.37b | 306.48 | ||
Mean | 161.50x | 259.17 | 354.38xy | 383.80 | 420.64 | 307.38 | ||
SEM | 18.89 | 34.12 | 36.44 | 34.88 | 39.78 | 38.47 | ||
Non-infested | n | 13 | 8 | 8 | 7 | 10 | 46 | |
mean | 161.69 | 265.50 | 327.25a | 379.57a | 409.00 | 295.46 | ||
Forest | Infested | n | 1 | 3 | 2 | 3 | 2 | 11 |
mean | 153.24 | 236.33 | 246.00b | 319.00b | 390.00 | 293.80 | ||
Mean | 137.16y | 257.55 | 311.00y | 361.40 | 405.83 | 295.16 | ||
SEM | 34.80 | 20.94 | 22.12 | 12.44 | 16.14 | 22.84 |
SEM – standard error of the mean; a, b – mean values of carcass weight of infested and non-infested individuals within an ecosystem marked with different letters differ significantly at P ≤ 0.05; x, y– mean values of carcass weight of individuals from different ecosystems marked with different letters differ significantly at P ≤ 0.05
Hierarchical ordering of the deer by carcass and antler weight indicates a clear dominance of individuals from agricultural ecosystems. Regarding the carcass weight trait, bucks from agroecosystems were the heaviest and the difference was statistically significant compared to the carcass weight of bucks from forest ecosystems. The highest weight of antlers was also recorded in roe from agroecosystems, but no statistically significant differences were found in this parameter between the regions of origin.
Roe deer are exposed to parasitic infestations in their living habitats. In Poland, a relatively large number of investigations have focused on the occurrence of endoparasites in the respiratory and digestive systems (8, 15, 24, 25, 31). Similar studies have also been conducted in other European countries (19, 35, 36). The results of research carried out in Portugal showed that nearly half of culled roe deer were infested with at least one parasite (11), and in Sweden, parasitic infestations were responsible for 10% of roe deer mortality (1).
Although studies on the occurrence of endoparasites in roe deer indicate the scale of the problem, infestations of cervid species by
There are almost no reports on the impact of this parasite on the condition of animals. Respiratory and nutritional disorders usually leading to severe emaciation are mainly reported. There are also disorders in the change of the hair coat or in velvet loss (27). The comparison of the carcass weights of bucks analysed in the present study with those of male roe deer culled in the same area at the beginning of the 2000s showed for the carcasses from 2020 higher weight of non-infested and lower weight infested male roe deer from field and grassland environments (10). Similarly, lower carcass weight was determined in all individuals from forest habitats in the present study compared to animals culled in the early 2000s. However, antler weight was higher in the present study than that noted in the 2000s, regardless of the presence of parasitic infestation and the living environment of the animals (10). In comparison with data from 2008 and 2010 on bucks from field and grassland habitats, carcass weight in non-infested animals was higher, whereas in infested animals it was lower. Irrespective of the presence of infestation, carcass weight in bucks from forest ecosystems was lower. In comparison with the results from 2008 and 2010, antler weight was higher in non-infested and lower in infested individuals, regardless of the habitat (12).
Carcass and antler weights in the infested and non-infested bucks harvested in the Lublin region were substantially higher than in the case of roe deer culled in south-western Poland (near Opole) in the 2012/13 hunting season (34). These parameters also exceeded those reported for bucks culled in the surroundings of Kraków, especially in older age groups (33). The present values were higher in both groups (infested/non-infested), especially in the case of older animals, than those determined by Wajdzik
The results of the study of