В феврале 2022 года в г. Мезени Архангельской области прошли XII Областные соревнования конников на лошадях мезенской породы. За два дня соревнований в семи видах испытано 18 лошадей. В ходе соревнований животные самой северной в России генофондно-племенной фермы СПК РК «Север» в непростых погодных условиях Крайнего Севера подтвердили свою высокую разностороннюю работоспособность. In February 2022, the XII Regional equestrian competitions on horses of the Mezenskaya breed were held in the town of Mezen, Arkhangelsk region. During two days of competition, 18 horses were tested in seven types. During the competition, the animals of the northernmost gene pool breeding farm in Russia of the SEC RK «North» in the difficult weather conditions of the Far North confirmed their high, versatile performance.

В Архангельской области на территории ФГБУ «Национальный парк «Кенозерский» с 21 по 24 июня 2022 года прошла IV Всероссийская научно-практическая конференция с международным участием «Аборигенные породы лошадей - национальное достояние России». В работе конференции приняли участие более 60 учёных, практиков, занимающихся вопросами сохранения местных пород лошадей, из 16 регионов России, а также республики Беларусь. В ходе работы заслушано 30 докладов, принято Постановление о необходимости дальнейшей работы Фонда аборигенных пород лошадей (ФАПЛ) и создания единой централизованной базы по местным породам. The IV All-Russian Scientific and Practical Conference with international participation «Aboriginal horse breeds - the national treasure of Russia» was held in the Arkhangelsk region on the territory of the Federal State Budgetary Institution «Kenozersky National Park» from June 21 to 24, 2022. The conference was attended by about 60 scientists and practitioners involved in the conservation of local horse breeds from 16 regions of Russia, as well as the Republic of Belarus. In the course of the work, 30 reports were heard, a resolution was adopted on the need for further work of the Fund of Aboriginal Horse Breeds (FAPL) and the creation of a unified centralized database on local breeds.

Мезенская порода лошадей имеет ограниченный генофонд. Основным местом разведения является Мезенский район Архангельской области, где функционируют одна генофондно-племенная ферма и ряд базовых хозяйств, в которых осуществляется селекционно-племенная работа с породой. Поголовье генофондной фермы СПК РК «Север» сформировано с использованием животных из разных населенных пунктов района с целью сохранения генетического разнообразия всей породы. В исследование взято все поголовье конефермы, имевшееся на 01.01.2022 г., в количестве 115 голов. Генетическую структуру данной популяции изучали по микросателлитам ДНК. Установлено, что она обладает широким генетическим разнообразием. Общее число идентифицированных аллелей по 17 локусам ядерной ДНК составило 115. Число аллелей в локусах варьирует от 3 до 10, при среднем значении 6,76 аллеля на локус. Наиболее высокий уровень полиморфизма отмечен в локусе ASB17, включающем 15 аллелей, а также в локусе HTG10 с числом аллелей 10. В локусе LEX3, локализованном на Х-хромосоме, определено 11 из 14 известных аллелей. Генетическая структура хозяйства включает в себя 79 типичных аллелей, частота встречаемости которых составляет более 5 %. Наиболее распространённые среди них: ASB23S (0,301), AHT5О (0,304) и N (0,327), ASB2К (0,314) и М (0,327), HTG10R (0,325), HMS2Н (0,331), HMS6Р (0,339), CA425N (0,375), HMS1J (0,411), LEX3М (0,442), AHT4О (0,444), HMS3М (0,461), HTG4М (0,464), HTG7О (0,589). Частота встречаемости редких в популяции аллелей варьирует от 0,012 до 0,049. В 3-х локусах выявлено 3 аллеля, которые определены лишь у единичных представителей хозяйства в гетерозиготном состоянии с частотой 0,006. Также в генотипе лошадей генофондной фермы обнаружено 3 приватных аллеля. Всего в 17 локусах микросателлитов у лошадей хозяйства выделено 274 генотипа, что составляет 16,12 генотипа на локус. Основная часть генотипов в хозяйстве (81,4 %) приходится на гетерозиготные варианты с частотой встречаемости от 60,0 % (HTG6) до 95,0 % (LEX3). За счёт высокого разнообразия генотипов средняя степень полиморфности поголовья рыбколхоза «Север» составляет 3,82. Отрицательное значение индекса фиксации (Fis) указывает на наличие генетического баланса в хозяйстве и отсутствие внутрипопуляционного инбридинга (Fis = -0,017), что, в свою очередь, говорит об эффективности селекционных мероприятий по сохранению и поддержанию генетического разнообразия, проводимых на генофондной ферме. The Mezen horse breed has a limited gene pool. The main breeding site is the Mezensky district of the Arkhangelsk region, where there is one gene-breeding farm and a number of basic farms in which breeding work with the breed is carried out. The livestock of the gene pool farm of the SEC RK «North» was formed using animals from different localities of the district in order to preserve the genetic diversity of the entire breed. The study took all the livestock of the horse farm, which was available on 01.01.2022, in the amount of 115 heads. The genetic structure of this population was studied by DNA microsatellites. It has been established that it has a wide genetic diversity. The total number of identified alleles for 17 nuclear DNA loci was 115. The number of alleles in the loci varies from 3 to 10, with an average value of 6.76 alleles per locus. The highest level of polymorphism was observed in the ASB17 locus, which includes 15 alleles, as well as in the HTG10 locus with the number of alleles 10. 11 out of 14 known alleles have been identified in the LEX3 locus localized on the X chromosome. The genetic structure of the farm includes 79 typical alleles, the frequency of occurrence of which is more than 5%. The most common among them are: ASB23S (0.301), ANT5O (0.304) and N (0.327), ASB2K (0.314) and M (0.327), HTG10R (0.325), NMS2H (0.331), NMS6P (0.339), CA425N (0.375), HMS1J (0.411), LEX3M (0.442), ANT4O (0.444), NMS3M (0.461), HTG4M (0.464), HTG7O (0.589). The frequency of occurrence of rare alleles in the population varies from 0.012 to 0.049. 3 alleles were identified in 3 loci, which were determined only in single representatives of the economy in a heterozygous state with a frequency of 0.006. Also, 3 private alleles were found in the genotype of horses of the gene pool farm. In total, 274 genotypes were isolated in 17 microsatellite loci in farm horses, which is 16.12 genotypes per locus. The main part of the genotypes in the farm (81.4%) are heterozygous variants with a frequency of occurrence from 60.0% (HTG6) to 95.0% (LEX3). Due to the high diversity of genotypes, the average degree of polymorphism of the livestock of the fish farm «North» is 3.82. A negative value of the fixation index (Fis) indicates the presence of a genetic balance in the farm and the absence of intra-population inbreeding (Fis = -0.017), which, in turn, indicates the effectiveness of breeding measures to preserve and maintain genetic diversity carried out on a gene pool farm.

Mezenskaya horse (Mezenka) is Russia’s aboriginal breed. It is a domestic selection in the northern territories of Arkhangelsk region. The breed is perfectly adapted to the conditions of the Far North, and has a number of valuable economic and biological qualities. At present, it has a limited gene pool and is bred only in the Mezensky district, where one gene pool-breeding farm is operating and so is a number of basic farms, where selection and breeding activities take place with the breed. Due to a small population of Mezen horses, the challenge of preserving its intra-breed diversity is very urgent. To determine the degree of genetic variability in the Mezen population, the alleles-fond was monitored. A comparative analysis of the genetic structure of the breed was done on DNA microsatellites at time-intervals of 10 years (2000, 2010 and 2020). Crista samples of 198 horses were studied in specialized laboratories. It was established that the breed has wide genetic diversity in 17 loci of nuclear DNA. The population’s alleles-fond includes from 128, 139, and 133 alleles respectively (with an average value of 7.53, 8.18, and 7.82 alleles per locus). The most common alleles are AHT4O , AHT5N , ASB2K , ASB23S , CA425N , HMS1J , HMS1M , HMS2H , HMS3M , HMS7L , HTG4M , HTG6O , HTG7K , HTG7O and LEX3M . Mezen horses revealed 6 rare, lowfrequency (0.004–0.056) alleles not found in the horse populations of domestic selection. The average value of the polymorphic level ( Ae ) in the breed over the years is 4.16, 4.21 and 4.06, respectively. The highest polymorphism is found in locus ASB17 (6.49–6.90–6.76); the lowest, in locus HTG6 (1.71–1.66–1.67) and HMS7 (1.77–1.95–1.77). A slight deficit of heterozygous genotypes ( Fis = 0.003) was observed in Mezen horses in 2010. In 2000 and 2020, the observed heterozygosity ( Ho ) exceeds the expected value ( He ), which indicates the absence of intra-population inbreeding ( Fis = –0.014 and –0.011, respectively). The results obtained testify to the effectiveness of breeding activities carried out to preserve, improve and maintain genetic diversity in the population.

Mezenskaya horse (Mezenka) is Russia’s aboriginal breed. It is a domestic selection in the northern territories of Arkhangelsk region. The breed is perfectly adapted to the conditions of the Far North, and has a number of valuable economic and biological qualities. At present, it has a limited gene pool and is bred only in the Mezensky district, where one gene pool-breeding farm is operating and so is a number of basic farms, where selection and breeding activities take place with the breed. Due to a small population of Mezen horses, the challenge of preserving its intra-breed diversity is very urgent. To determine the degree of genetic variability in the Mezen population, the alleles-fond was monitored. A comparative analysis of the genetic structure of the breed was done on DNA microsatellites at time-intervals of 10 years (2000, 2010 and 2020). Crista samples of 198 horses were studied in specialized laboratories. It was established that the breed has wide genetic diversity in 17 loci of nuclear DNA. The population’s alleles-fond includes from 128, 139, and 133 alleles respectively (with an average value of 7.53, 8.18, and 7.82 alleles per locus). The most common alleles are AHT4O, AHT5N, ASB2K, ASB23S, CA425N, HMS1J, HMS1M, HMS2H, HMS3M, HMS7L, HTG4M, HTG6O, HTG7K, HTG7O and LEX3M. Mezen horses revealed 6 rare, lowfrequency (0.004–0.056) alleles not found in the horse populations of domestic selection. The average value of the polymorphic level (Ae) in the breed over the years is 4.16, 4.21 and 4.06, respectively. The highest polymorphism is found in locus ASB17 (6.49–6.90–6.76); the lowest, in locus HTG6 (1.71–1.66–1.67) and HMS7 (1.77–1.95–1.77). A slight deficit of heterozygous genotypes (Fis = 0.003) was observed in Mezen horses in 2010. In 2000 and 2020, the observed heterozygosity (Ho) exceeds the expected value (He), which indicates the absence of intra-population inbreeding (Fis = –0.014 and –0.011, respectively). The results obtained testify to the effectiveness of breeding activities carried out to preserve, improve and maintain genetic diversity in the population.

The Mezen horse breed is a local breed of the Arkhangelsk region and is bred on the territory of the Mezen region. Currently, the population of the Mezen breed is low (the number of females is less than 200 heads). At the same time, the highly adaptive qualities of the Mezen horses and the low-cost technology of their keeping contribute to the development of developing horse breeding in the region, which is one of the ways to increase the livestock population. In this case,the stallions and mares, which most fully meet the breed requirements for a complex of breeding traits, are used for the purpose of reproduction on farms, and the rest of the growing stock can be used to produce inexpensive horse meat, while the production of colt meat being the least expensive. The analysis of the quality of meat productivity of 6-month-old stallions of the Mezen breed was performed for the carcasses on the whole and for six separate parts obtained in the process of cutting each of the carcasses. The largest specific weight in the carcass is the leg cut (37.7 ± 0.49%). It also has the highest muscle tissue content – 71.5 ± 0.25%. The high content of boneless meat is in the humeroscapular and the dorsiventral cuts – 65.7% and 65.9%, accounting for 23.3% and 22.6% of the total carcass weight, respectively. The average content of connective tissue was 4.7 ± 0.44%, bones – 27.2 ± 1.21%. The average meat yield was 67.7 ± 0.15%, or 66.9 ± 3.26 kg. In terms of chemical composition, the growing stock meat at the age of weaning has a high nutritional and biological value. The weight content of protein is 21.2%, moisture – 74.3%, fat – 3.8%. Colt meat has a high ecological purity, which is confirmed by the results of its analysis for the content of heavy metals, the amount of which is significantly below the maximum allowable concentration (MAC) level. In terms of organoleptic properties, boiled colt meat and broth obtained from it were given 7.3 and 7.5 points on a 9-point scale, respectively. The results obtained confirm the possibility of using growing stock Mezen horses at the weaning age for the production of colt meat in the Mezen district of the Arkhangelsk region.

Представлен анализ современного состояния генеалогической структуры мезенской породы лошадей и дана характеристика современных линий и семейств породы. The analysis of the current state of the genealogical structure of the Mezenskaya breed and the characteristics of modern lines and families of the breed are given.

Начатая с 1993 года работа по сохранению генофонда мезенской породы лошадей предполагает и работу со структурными единицами породы. Для определения маточной структуры были обработаны документы Мезенского районного архива за период с 1930 по 1968 гг., на основании которых были выделены родоначальницы и составлены схемы маточных семейств. В 1993 году маточная структура схематично была представлена 37 семействами с живыми потомками (условное название - «старая»). Дальнейшая реорганизация, а затем и ликвидация семи из двенадцати сельхозпредприятий района и сокращение численности конепоголовья в последующие десятилетия повлияли на состояние материнской генеалогии. Согласно инвентаризации семейств, проведённой в 2006 году, она включала в себя уже 26 семейств. Основная доля конематок (30,2 %) принадлежит к семействам Лямки, Форсунки и Семилетки. Десять семейств представлено маточным поголовьем с численностью от 1 до 3 голов. В целях сохранения генетического разнообразия в породе племенная работа ведётся со всеми семействами. Work begun since 1993 on the conservation of gene pool of the Mezenskaya horse breed involves work with the structural units of the breed. To determine the females structure, the documents of the Mezensky District Archive were processed for the period from 1930 to 1968. On the basis of that work the ancestors were identified and schemes of the families were compiled. In 1993, the females structure was schematically represented by 37 families having descendants that live nowadays (the conditional name is “old”). Further reorganization that was followed by liquidation of seven out of twelve farms in the Region and a reduction in the number of horse stock in the following decades influenced the state of maternal genealogy. According to the 2006 family inventory, it included already 26 families. The main share of mares (30.2%) belongs to the families of Lamka, Nozzles and Sevens. Ten families are represented by breeding stock with numbers from 1 to 3 animals. It is carried out the breeding work with all the families to preserve the genetic diversity in the breed.

Обработка данных районных племенных книг лошадей мезенской породы и других архивных документов позволила выделить ряд основных производителей, к которым восходят родословные современных жеребцов, и определить родоначальников линий. Первые схемы генеалогических линий породы были составлены в середине 90-х годов ХХ в. К 2006 году, в связи с распадом большинства хозяйств Мезенского района и сокращением численности лошадей, линейная структура породы претерпела ряд изменений. Многие «ветви» линий прекратили своё существование, в ряде линий через наиболее многочисленные ветви произошла трансформация в «новые» структурные единицы. С 2006 года линейная структура породы представлена 6-ю линиями, имеющими живых продолжателей, и 1-й родственной группой. Она является действующей в настоящее время. Наиболее многочисленная и самая перспективная линия Кустика составляет 31,5% в общей структуре. Линия Химика занимает второе место (23,7 %). На остальные структурные единицы приходится 44,8% поголовья породы. Племенная работа ведётся со всеми линиями. Используя методы селекционно-племенной работы, мы благополучно избегаем близкого инбридинга, сохраняя при этом генеалогическое разнообразие. Processing data from the district stud books of horses of the Mezenskaya breed and other archival documents made it possible to identify a number of the main sires, to which the pedigrees of modern stallions are traced, and to determine the progenitors of the lines. The first genealogical lines of the breed were composed in the mid-90s of the twentieth century. By 2006, due to the collapse of most farms in the Mezen district and a decrease in the number of horses, the linear structure of the breed underwent a number of changes. Many “branches” of lines ceased; in a number of lines, through the most numerous branches, a transformation into “new” structural units took place. Since 2006, the linear structure of the breed is being represented by 6 lines with living successors and by one related group that is current. The most numerous and most promising is the line of Kustik, 31.5% of the total structure. The Himik line takes second place (23.7%). The remaining structural units account for 44.8% of the breed. Tribal work is carried out with all lines. Using methods of breeding, we safely avoid close inbreeding maintaining genealogical diversity.

В статье представлены результаты испытаний рабочих качеств мезенских лошадей с середины XIX века и по на стоящее время. Подробно описана современная система испытаний, позволяющая выявить лошадей с универсальной работоспособностью. Приведены лучшие показатели по видам испытаний и Абсолютные чемпионы соревнований. Представлена информация об использовании мезенок в других сферах. There are reported the results of testing of working qualities of horses of Mezenskaya breed from the middle of the XIXth century to nowadays in the article. The current system of testing is given in detail that permits to identify horses of universal performance. The best results in different kinds of tests are given alongside with Absolute Champions. The information on use of Mezenskaya horse breed in other areas is also included.