Eurasian Journal of Zoology

Nutritional Influences on Reproductive Performance in Breeding Bulls

2026-05-22T13:39:40+03:00

Reproductive performance in animals is a productivity parameter shaped by the individual or combined effects of factors such as genetics, environment, climate, nutrition, management, stress and temperament. Among these factors, nutrition plays a significant role in maximising the reproductive potential of bulls. Inadequate or unbalanced nutrition leads to a reduction in androgen secretion and a decline in sperm quality in adult male animals. Consequently, the bull’s nutritional status is one of the primary factors determining sperm quantity and quality. In particular, by feeding calves a ration with high nutritional value during the pre and post-weaning stages and ensuring adequate nutritional intake, the bulls’ reproductive function can be maximised. Furthermore, physical health, which is directly linked to the bull’s reproductive performance, can be achieved by reaching an appropriate live weight through appropriate feeding strategies. An optimal feeding program not only helps bulls remain physically healthy but also influences gonadotropin secretion and, consequently, their reproductive performance. Therefore, ensuring an adequate intake of energy, protein, minerals and vitamins at different stages of growth and reproduction is crucial for maximising the reproductive potential of bulls. This review examines experimental and field studies covering the effects of certain nutrients on key reproductive parameters such as semen quality, hormonal balance and spermatogenesis, which influence the reproductive performance of breeding bulls, as well as feeding strategies implemented to improve their fertility levels.

Determination of Living Harmful and Beneficial Insect Species of Garlic (Allium sativa) of Taşköprü and Hanönü Districts, Kastamonu Province

2026-06-15T10:19:35+03:00

Garlic (Allium sativum L.) is one of the most economically important vegetable crops cultivated worldwide and constitutes a significant component of agricultural production in Türkiye, particularly in Kastamonu Province. In addition to its nutritional and medicinal value, garlic production plays an important role in the regional economy of Taşköprü and Hanönü districts. Despite the economic importance of garlic cultivation, information regarding the diversity of harmful and beneficial insect species associated with garlic agroecosystems in the region remains limited. Therefore, this study was conducted to determine the insect fauna inhabiting garlic cultivation areas and to identify species with potential economic importance.

Field surveys were carried out between May and August 2016 in garlic fields and adjacent habitats located in Taşköprü and Hanönü districts of Kastamonu Province, Türkiye. Insect specimens were collected using sweep nets and beating sheet methods from 68 sampling localities representing different habitat types. Collected specimens were prepared according to standard entomological techniques and identified using morphological characters and taxonomic keys.

A total of 761 specimens representing 81 species belonging to six insect orders were identified. The recorded fauna consisted of 38 species of Coleoptera, 15 species of Lepidoptera, 9 species of Neuroptera, 9 species of Odonata, 7 species of Diptera, and 3 species of Heteroptera. Beneficial species were primarily represented by Odonata, Neuroptera, and several Diptera and Coleoptera taxa, whereas most Lepidoptera and Heteroptera species, together with some Coleoptera species, were classified as potentially harmful. The occurrence of predatory species such as Chrysoperla carnea, Scymnus quadriguttatus, and Scymnus rubromaculatus indicates the presence of a considerable natural biological control potential within the garlic agroecosystem. In contrast, species such as Lilioceris merdigera, Cassida viridis, and Hellula undalis may pose potential risks to garlic production under favorable environmental conditions.

The results demonstrate that garlic cultivation areas in Taşköprü and Hanönü support a rich and diverse insect fauna comprising both beneficial and harmful species. This study represents one of the most comprehensive faunistic investigations conducted in garlic agroecosystems of the region and provides valuable baseline data for future biodiversity assessments, integrated pest management (IPM) programs, biological control applications, and sustainable garlic production strategies.

Effects of Soil and Vegetation Characteristics on Nematode Biodiversity and Community Structure in Forest Ecosystems of Adana Province, Türkiye

2026-06-15T09:49:42+03:00

This study was conducted to investigate the relationships between nematode biodiversity and soil and vegetation characteristics in forest ecosystems located in six sub-regions with different topographic and edaphic properties in Adana Province, Türkiye. Soil samples were collected from 0–30 cm and 30–60 cm depths in Sarıçam, Çukurova, Salbaş, Varda, Bürücek and Pozantı sub-regions. Nematodes were extracted, identified at the genus level and classified into trophic groups. Soil physical and chemical properties including pH, organic matter, texture, lime content and nutrient status were analyzed to evaluate their relationships with nematode community structure. The results revealed significant differences among sub-regions in terms of nematode abundance, diversity and trophic composition. Bacterivorous nematodes represented the dominant trophic group, while predatory and omnivorous nematodes showed relatively lower diversity. All soils exhibited alkaline characteristics, and soil organic matter and texture were identified as the main factors influencing nematode communities. Higher nematode abundance and diversity were observed in soils rich in organic matter and with loamy texture, whereas sandy soils with low organic matter content supported less diverse communities. Nematode abundance was generally higher in the upper soil layer (0–30 cm) than in deeper soil layers. The findings demonstrate that nematode biodiversity is strongly associated with edaphic factors, particularly soil organic matter and texture, and confirm the usefulness of nematodes as reliable bioindicators for assessing soil ecosystem condition in forest environments.

First record of Curteria episcopalis (C. L. Koch, 1837) (Acari: Erythraeidae) from Türkiye

2026-06-23T16:36:14+03:00

Curteria episcopalis (C. L. Koch, 1837) is recorded for the first time from Türkiye, based on six free-living adults from Erzincan (north-eastern) and Muğla (south-western) provinces. Diagnoses and morphometric data for adults are given. The record raises the number of Curteria species known from Türkiye to three.

Biology of Rock Dove (Columba livia Gmelin, 1789) in Isparta Centrum

2026-06-25T23:09:35+03:00

Due to the proximity of domestic waste in the city center and agricultural areas, Isparta provides a suitable habitat for the Rock Pigeon. In our country, there are almost no detailed studies on this species beyond its economic importance from a scientific perspective. Therefore, this study aims to reveal the species' ecology, population size, feeding and shelter areas, breeding success, and interactions with humans. Observation locations include the Süleyman Demirel University (SDÜ) campus area, the vicinity of Aliköy, the vicinity of Deregümü village, and the Ayazmana picnic area. Morphological characteristics, area selection and use, breeding, and comfort behaviors were determined using transect and classical observation methods. The average incubation period was determined to be 18.42 days, and the breeding success rate was 68.42%.