vetpressАграрная наукаAgrarian science0869-81552686-701XРедакция журнала "Аграрная наука"10.32634/0869-8155-2026-407-06-36-47vetpress-4210Research ArticleВЕТЕРИНАРИЯVETERINARY MEDICINEВлияние этиологии заболеваний на лактационные и репродуктивные показатели выбракованных коров и первотелокImpact of Disease Etiology on Lactation and Reproductive Performance in Culled Cows and First-Calf Heifershttps://orcid.org/0000-0002-8086-1788КрупинЕ. О.KrupinE. O.

Евгений Олегович Крупин, доктор ветеринарных наук, ведущий научный сотрудник отдела физиологии, биохимии, генетики и питания животных 

ул. Оренбургский тракт, д. 48, Казань, 420059

Evgeny Olegovich Krupin, Doctor of Veterinary Sciences, Leading Researcher of the Department of Physiology, Biochemistry, Genetics and Animal Nutrition

48 Orenburg tract, Kazan, 420059

evgeny.krupin@gmail.comТатарский научно-исследовательский институт сельского хозяйства — обособленное структурное подразделение Федерального государственного бюджетного учреждения науки «Федеральный исследовательский центр «Казанский научный центр Российской академии наук»РоссияTatar Scientific Research Institute of Agriculture —subdivision of the Federal State Budgetary Institution of Science “Kazan Scientific Center of the Russian Academy of Sciences”Russian Federation202604072026063647Copyright © Крупин Е.О., 20262026Крупин Е.О.Krupin E.O.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://www.vetpress.ru/jour/article/view/4210Актуальность

Актуальность. Достаточно велика доля животных, выбракованных из стад, особенно высокопродуктивных, по причине различных болезней.

Методы

Методы. Материалом послужила информация из базы программы племенного учета «ИАС «СЕЛЭКС» — Молочный скот. Племенной учет в хозяйствах», касающаяся 33982 коров и первотелок, выбывших из молочных стад 26 сельскохозяйственных предприятий Республики Татарстан в период с 2001 по 2023 гг. вследствие болезней: акушерско-гинекологических (АГБ), внутренних незаразных (ВНБ), хирургических (ХБ), инфекционных и инвазионных (ИИБ).

Результаты

Результаты. Получены новые знания о продолжительности отдельных периодов продуктивного и репродуктивного цикла. Продолжительность лактации выбракованных первотелок составляла в среднем 401,18 день; периода от отела до первого осеменения — 98,08 дней, от отела до первого плодотворного осеменения (сервис-период) — 160,75 дней. Продолжительность лактации у выбывших коров составляла в среднем 345,74 дня; сухостойного периода — 62,60 дня; периода от отела до первого осеменения — 86,32 дня; периода от отела до первого плодотворного осеменения (сервис-период) — 146,27 дней; межотельного периода — 415,30 дней. У выбракованных первотелок имелись значимые связи продолжительности лактации между группами нозологий — АГБ с ВНБ и ИИБ; продолжительности сервис-периода между группами нозологий — АГБ с ВНБ и ХБ, ВНБ с ХБ, ХБ с ИИБ. У выбывших дойных коров наиболее часто значимые различия продолжительности изучаемых периодов наблюдались в парах АГБ с ВНБ. Если рассматривать показатели за все лактации в среднем, с равной частой значимые различия выявлены в парах АГБ с ВНБ и ХБ, а также ВНБ с ХБ. С точки зрения последней законченной лактации и максимальной лактации, между величинами при АГБ и ВНБ.

Relevance

Relevance. The proportion of culled animals, particularly from high-producing herds, remains significantly high due to various diseases.

Methods

Methods. This study draws upon data from the breeding registry database “IAS SELEX — Dairy Cattle. Breeding Records in Farms,” encompassing 33,982 cows ann heifers culled from the dairy herds of 26 agricultural enterprises in the Republic of Tatarstan between 2001 and 2023. The culling was attributed to the following disease categories: obstetric-gynecological (OGD), internal non-communicable (INCD), surgical (SD), and infectious and invasive diseases (IID).

Results

Results. The research yielded new insights into the duration of key productive and reproductive intervals. For culled first-calf heifers, the average lactation length was 401.18 days; the calving to-first-insemination interval was 98.08 days; and the calving-to-conception interval (service period) was 160.75 days. For culled cows, the average lactation length was 345.74 days; the dry period lasted 62.60 days; the calving-to-first-insemination interval was 86.32 days; the calving-to-conception interval (service period) was 146.27 days; and the calving interval was 415.30 days. In culled first-calf heifers, significant correlations in lactation duration were found between specific nosology groups: OGD with INCD, and OGD with IID. For the service period, significant correlations were observed between OGD and INCD, OGD and SD, INCD and SD, and SD and IID. Among culled dairy cows, the most frequent significant differences in the duration of the studied periods were found in comparisons involving OGD and INCD. When analyzing average values across all lactations, significant differences occurred with comparable frequency in the OGD–INCD, OGD–SD, and INCD–SD pairs. Considering the last completed lactation and the maximum lactation, the most pronounced significant differences were consistently observed between the groups with OGD and INCD.

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The authors declare that there are no conflicts of interest present.