Evaluation of the hatching and productive qualities of ducks in the northern region of Kazakhstan

Avaliação das qualidades de incubação e produtivas de patos na região norte do Cazaquistão

Abstract

This article presents the results of research on the productive and incubation indicators of ducks from the mother flock of the “Kyzylzhar”, “Cherry Valley”, and “Ansar” crosses at the “Bishkulskaya poultry farm” LLP in the northern region of the Republic of Kazakhstan. The main factor hindering the development of duck farming in Kazakhstan is the lack of breeding and selection work. The intensive technology of industrial duck farming and housing involves maintaining and improving the breeding and productive qualities of the birds, as well as the specialized lines and promising breeds. The improvement of existing crosses and the development of new ones is a continuous breeding process. The incubation and productive qualities of ducks of three crosses were evaluated in the northern region of Kazakhstan. The indicators characterizing the reproductive and economically important traits of ducks adapted to the climatic conditions of the region were established. The obtained data allow for targeted selection to create and preserve highly productive poultry capable of efficient egg and meat production, adapted to both industrial and farm conditions. The analysis of our research results demonstrates that purposeful breeding work with the “Ansar” cross ducks ensures a stable annual improvement in their productive and reproductive characteristics. In particular, the “Ansar” ducks significantly outperform the “Kyzylzhar” cross, demonstrating a higher live weight (by 689.8 g) and a higher hatchability rate (by 7.3%). Taking into account that the heterosis effect is directly related to genetic differences, we propose using combinations of crossing “Ansar 1” with “Cherry Valley 2” and “Ansar 2” with “Cherry Valley 1”. Our data indicate that these pairs have greater genetic divergence compared to the “Kyzylzhar” cross lines, which opens up opportunities for achieving more pronounced heterosis and, consequently, improving productive traits.

Keywords:
cross; selection; fertilization; hatchability; live weight

Resumo

Este artigo apresenta os resultados de uma pesquisa sobre os indicadores produtivos e de incubação de patos provenientes do plantel matriz dos cruzamentos "Kyzylzhar", "Cherry Valley" e "Ansar", na granja avícola "Bishkulskaya" (LLP), localizada na região norte da República do Cazaquistão. O principal fator que dificulta o desenvolvimento da criação de patos no Cazaquistão é a falta de trabalhos de melhoramento genético e seleção. A tecnologia intensiva de criação industrial e o sistema de alojamento de patos envolvem a manutenção e o aprimoramento das qualidades reprodutivas e produtivas das aves, bem como das linhagens especializadas e raças promissoras. O aperfeiçoamento dos cruzamentos existentes e o desenvolvimento de novos constituem um processo contínuo de melhoramento genético. Foram avaliadas as qualidades de incubação e produtivas de patos de três cruzamentos na região norte do Cazaquistão. Foram estabelecidos indicadores que caracterizam os traços reprodutivos e economicamente importantes de patos adaptados às condições climáticas da região. Os dados obtidos permitem uma seleção direcionada para criar e preservar aves de alta produtividade, capazes de produzir ovos e carne de forma eficiente e adaptadas tanto a condições industriais quanto a sistemas de criação em granjas. A análise dos resultados de nossa pesquisa demonstra que o trabalho de melhoramento direcionado com os patos do cruzamento "Ansar" garante uma melhoria anual estável em suas características produtivas e reprodutivas. Em particular, os patos "Ansar" superam significativamente o cruzamento "Kyzylzhar", apresentando maior peso vivo (689,8 g a mais) e maior taxa de eclosão (7,3% a mais). Levando em conta que o efeito de heterose está diretamente relacionado às diferenças genéticas, propomos utilizar combinações de cruzamento entre "Ansar 1" e "Cherry Valley 2", e entre "Ansar 2" e "Cherry Valley 1". Nossos dados indicam que esses pares apresentam maior divergência genética em comparação com as linhagens do cruzamento "Kyzylzhar", o que abre oportunidades para alcançar uma heterose mais pronunciada e, consequentemente, melhorar as características produtivas.

Palavras-chave:
cruzamento; seleção; fertilização; taxa de eclosão; peso vivo

1. Introduction

According to the FAO-OECD forecast, the population will increase by 729 million by 2034, reaching about 8.8 billion people, with an average growth rate of 0.8% per year. According to the UN’s long-term estimates, the global population will continue to grow, reaching a peak of approximately 10.3-10.4 billion by the mid-2080s, and then gradually begin to decline.

In this regard, poultry farming plays a special role as the largest supplier of complete animal protein, which plays a significant role in human nutrition. According to estimates, global meat production increased by 1.3% in 2024, reaching 365 million tons. This increase was primarily driven by the growth of poultry meat production.

By 2034, annual per capita consumption is projected to increase by 0.9 kg per capita per year in edible retail weight (ERW) equivalent. In high-income countries, consumers are increasingly focused on animal welfare, the environment, and health, which has led to stagnant per capita meat consumption in some cases. Consumers are changing their preferences, often reducing their consumption of meats such as beef and pork in favor of poultry.

The global increase in poultry protein consumption as a share of total meat protein consumption has been a major driver of meat consumption growth over the decades, and this trend is expected to continue. By 2034, poultry meat will account for 45% of the protein consumed from all sources of meat. This is due to several factors, including its low cost (poultry meat remains the most affordable meat) and its favorable nutritional profile with a higher protein-to-fat ratio compared to other types of meat. Environmental considerations also contribute to the shift towards poultry meat, as the production of red meat requires more resources and leads to increased greenhouse gas emissions. Therefore, poultry meat is more appealing to consumers who prioritize sustainability (OECD, 2025).

The breeding of waterfowl, namely ducks and geese, plays a significant role in solving the problems of increasing poultry meat production.

Given that separate statistics on waterfowl are not kept in the Republic of Kazakhstan, and based on the average global ratios, the share of duck meat is 4.2%, and that of goose meat is 2.8% of the total poultry meat production.

Ducks are highly viable and adapt well to environmental conditions. Domestic ducks weigh 3-4 kg, while ducks weigh 2-3.5 kg. The average annual egg production is up to 250 eggs. Domestic duck breeds are divided into meat breeds (Peking, Grey Ukrainian, Black White-Breasted), meat-and-egg breeds (Mirror, Khaki-Campbell), and egg breeds (Indian Runner).

The northern region of Kazakhstan has favorable natural and climatic conditions for breeding ducks and geese. The North Kazakhstan region is home to a large number of lakes and pastures, which provide an advantage for the efficient and intensive production of agricultural waterfowl products.

Weather conditions, climate, and the geographical location of the farm are key exogenous factors that determine the productivity, physiological state, and adaptive potential of agricultural ducks. Temperature fluctuations, relative humidity, insolation, and the seasonality of precipitation have a direct impact on feed consumption, growth rate, egg production, reproductive performance, and mortality rates, as well as on the prevalence of infectious diseases and stress-induced conditions (Applegate and Angel, 2014; Ismoyowati and Sumarmono, 2019). The climate zone determines the requirements for indoor microclimate, ventilation systems, planting density, and water access, which affects the economic efficiency of production (Ismoyowati and Sumarmono, 2019; Nicol and Davies, 2013). The geographical location of the farm affects the availability of feed resources, the quality of water supply, the epizootic situation in the region, and the logistics of product sales. In the context of global climate change, which is accompanied by an increase in the frequency of extreme temperatures and changes in the hydrological regime, there is an increasing need to adapt the technologies of housing and breeding programs aimed at increasing the resistance of ducks to adverse environmental factors (House et al., 2023).

According to the Bureau of National Statistics, the volume of poultry meat production in Kazakhstan increased by 9.4% from January to November 2024 compared to the same period in 2023. During this period, domestic enterprises produced 326.3 thousand tons of poultry meat. In 2024, Kazakhstan sold 409.3 thousand tons of poultry meat on its domestic market, which is 1% more than in the corresponding period in 2023 (405.4 thousand tons). As of January 1, 2026, the number of birds increased by 6.9% compared to the previous year, reaching 48,619,958. In 2025, the volume of poultry slaughter in all categories of farming amounted to 466,721.9 tons in live weight and 371,687.0 tons in slaughter weight, an increase of 4.8% in live weight and 3.6% in slaughter weight compared to the corresponding period last year. The production of chicken eggs increased by 2.4% in 2025, reaching 4,568,532.4 thousand units (Bureau of National Statistics of the Agency for Strategic Planning and Reforms of the Republic of Kazakhstan, 2025).

The development of industrial duck farming requires the development of breeding work, the improvement of poultry productivity, consumer qualities, and adaptability to housing conditions. Therefore, in recent years, research work on duck breeding has been conducted in the republic. Thus, within the framework of the scientific and technical program of the Ministry of Agriculture of the Republic of Kazakhstan “Development of technologies for effective management of the breeding process in poultry farming” for 2021-2023, poultry scientists bred the “Ansar” duck cross, which has sufficient genetic potential for productivity and high preservation (Nametov et al., 2023), since the development of poultry farming will continue to be based on when using hybrid poultry obtained as a result of crossing according to certain schemes, it is necessary to constantly work on increasing the heterotic effect based on the compatibility of breeds, crosses and lines adapted to the climatic conditions of the northern region of Kazakhstan.

The northern region of Kazakhstan is located in a sharply continental climate zone and is characterized by specific meteorological and geographical conditions that have a significant impact on the possibility of industrial duck farming. According to the North Kazakhstan branch of the Republican State Enterprise Kazhydromet, the average annual air temperature in the region is about +1.0°C, with a pronounced amplitude of seasonal temperature fluctuations: the average temperature of the coldest month (January) is -18-20°C, and the warmest month (July) is +18-20°C. The relatively cool summer season and the absence of prolonged extremely high temperatures help reduce heat stress in waterfowl and improve their physiological condition and productivity. The duration of daylight hours in the summer months reaches 16-17 hours, which is an additional factor that has a positive effect on the growth and development of ducks. The presence of a significant number of natural and artificial water bodies provides conditions for the realization of the biological characteristics of waterfowl. The predominantly flat terrain of the region creates the preconditions for the rational placement of duck farms. Taken together, the climatic, meteorological, and geographical characteristics of the North Kazakhstan region form a natural basis for the development of industrial duck farming (Kazhydromet Kazakhstan, 2025).

When raising and keeping line and hybrid birds under the same conditions, it is possible to determine the relative value of a particular parent breed, cross, or line in various crossbreeding combinations and to identify effective ways to use this data to produce highly heterosis birds.

Ducks are characterized by a high level of genomic plasticity, rapid metabolism, and a short reproductive cycle. These features make them a promising target for both classical and molecular genetic breeding methods. The use of differentiated selection methods based on a set of productive traits (live weight, egg production, and offspring survival) significantly increases the breeding value of the parent forms (Fakhrtdinova and Shilov, 2023).

In global poultry farming, a lot of attention is paid to studying the interaction between genotype and environment. Numerous research papers have emphasized (Roiter et al., 2020; Tajieva, 2007) the importance of the interaction between different genotypes and environmental factors such as the location of the test, feeding and housing conditions, light regime, and temperature. These factors have a significant impact on traits such as productivity, viability, growth, sexual maturity, egg weight, feed consumption, external and internal egg quality traits, and carcass quality traits (Chen et al., 2015; Kamal et al., 2022).

It is known that the phenotype of an individual is determined by the interaction of the genotype and the environment, and the influence of paratypic factors (external environment) often prevails. This is especially evident in the breeding of highly productive poultry breeds and lines. The interaction of the genotype and the external environment determines the development of quantitative traits of productivity. These interactions are crucial for achieving a certain level and quality of production. The genotype is not the only factor that determines the level of productivity. In relation to different environmental conditions, genotypes have different abilities to respond to conditions, regardless of the productivity level of the poultry lines. If these reactions have different or even opposite directions in individual genotypes, they are of great importance for the planning and execution of breeding work, and this should be taken into account in multilateral breeding and used to improve economically important productivity traits, as the different ability to respond to different external conditions is controlled genetically and is inherited. As external conditions change, the position of genotypes in relation to observed productivity traits also changes.

Thus, without taking into account the various territorial conditions of production and the interaction between genotype and environment, modern targeted and extensive planning and breeding work would not be complete. Only birds that have shown high viability and optimal productivity when tested in the production and climatic conditions of the local area should be used in production (Temirbekova, 2009).

The research was conducted as part of the scientific and technical program for 2024-2026, which aims to develop effective methods for breeding waterfowl using breeding and technological methods and information technologies. During the research period, the birds were kept at the “Bishkulskaya poultry farm” LLP, which is located in the most remote northern part of the Republic. The region is easily affected by both cold Arctic and warm air masses from Central Asia, resulting in frequent weather changes. The climate of this zone is sharply continental, with cold, long winters and hot summers, and large fluctuations in air temperature during the winter and summer, as well as during the day and night.

Winter is long, with a stable snow cover, and severe frosts and snowstorms. The period of stable snow cover is more than 6 months. The snow cover height ranges from 12 to 35 cm. The water reserves in the snow are about 50-69 mm, which is 22-23% of the total moisture supply. In summer, on some hot days, the air temperature rises to +41.0°C, and in winter it drops to minus –30.0-35.0°C, but sometimes it drops below –40.0-45.0°C. Spring is short (20-30 days), dry, and cool, and it begins in the second half of April. The temperature rises above +5°C on April 20-22, and above +10°C on May 8-10. Spring moisture reserves in the soil are mainly created by autumn-winter precipitation and are the main source of water supply for plants during the initial period of their vegetation. In May and June, there are often dry winds and dust storms. In autumn, the transition of temperatures through +10°C occurs on average on September 17-20. At this time, the vegetation period of plants ends. On average, the frost-free period lasts 120-130 days. The average annual precipitation varies from 300 to 330 mm, of which 60% falls during the vegetation period. The highest precipitation occurs in July and August (58-48 mm). Precipitation is unevenly distributed over the years. In some years, precipitation is significantly lower than normal, while in other years, it is 1.5-2 times higher than normal. The area is characterized by June droughts. Late spring and early autumn frosts are common, and early spring droughts are observed. The annual precipitation ranges from 280 to 360 mm.

The relief of the area is a low-lying, flat, and slightly undulating plain, with a large number of shallow depressions occupied by lakes. From the south-east to the north-east, the area is crossed by the Ishim River, which serves as a channel for the flow of surface runoff. The natural and climatic conditions of the region, as well as its territorial location and proximity to regional processing enterprises, create favorable conditions for the breeding of waterfowl.

In this work, the main research is focused on evaluating the incubation and productive qualities of ducks in the natural and climatic conditions of the northern region of Kazakhstan, which is relevant and requires finding solutions.

Targeted activities to preserve the gene pool of agricultural poultry are impossible without reliable information on the use of specific breeds, lines, and crosses of waterfowl in production, as well as the conditions for their breeding, taking into account the natural and climatic features of the northern region of Kazakhstan.

2. Materials and Methods

2.1. Zootechnical research methods

Breeding work with ducks is based on the methods and techniques used in breeding meat poultry (chickens, turkeys, geese, etc.). However, there are also specific features and differences due to the biological characteristics of this type of poultry (growth and development patterns, excessive body fat, narrow sex ratio, and nesting productivity).

Methodological and information base of the study consists of the results of fundamental and applied research of domestic and foreign scientists in the field of poultry (Mazloev et al., 2005; Mazloev et al., 2009; Fisinin et al., 2025; Shevyakov et al., 2019; Romanenko, 2022; Saginbayeva et al., 2023).

Program of breeding ducks forming birds breeding nucleus through the acquisition of breeding nests and laying new lines, differential selection on the basis of specialization, and breeding for compatibility with the result of the analysis of PCR for marker genes.

The objects of the study were waterfowl of the collection herd of crosses “Kyzylzhar”, “Cherry Valley”, “Ansar” of the poultry farm of the northern region of Kazakhstan.

Work with the breeding core was carried out by methods of family and combined selection (family with individual assessment of each individual).

To establish duck lines, families with optimal live weight, high hatchability, viability, and standard egg production were used as father lines; families with high egg production (peak value and stability of egg production), viability, egg hatchability, and other characteristics typical of Peking ducks were used as mother lines.

The selected traits in the paternal lines for ducks were: live weight of ducklings at 7 weeks of age, meat body shapes, feed consumption per 1 kg of live weight gain, and livestock preservation during 1-7 weeks of life. The reproductive qualities of parents (egg production, fertilization, and egg hatchability) were taken into account. At the age of 7 weeks, the heaviest bird, typical in appearance, was selected.

In the maternal line, the main selected traits were: egg production, duckling hatching percentage, feed consumption per unit of production, growth rate of linear and hybrid young birds, and their preservation up to 7 weeks of age. The selection of the maternal line was aimed at increasing fertility and reducing feed consumption per unit of production, while maintaining standard live weight at 7 weeks of age.

As part of the scientific and technical program “Development of effective methods for breeding waterfowl using breeding and technological methods and information technologies” BR22887152 for 2024-2026, a program and methodology was approved that provides for the strict differentiation of lines based on specialization. The ratio of ducks and drakes in each nest was 1:4.

The reproduction of the flock was carried out at the peak of egg production from ducks that were at least 9 months old.

During the breeding period, each egg was marked with the date of collection and the egg-laying bird’s number using a pencil. After removing the trays from the hatching cabinet, each day-old chick was assigned an individual number, which was recorded in a special form. This ensured the preservation of the bird’s genealogy. After the first evaluation at 7 weeks of age, the selected replacement chicks were assigned individual leg numbers (leg rings). All data from ringing and individual weighing were also recorded in dedicated forms.

When assembling the breeding nests, special attention was paid to the specialization of the paternal and maternal lines. The males and females in the breeding nests were selected from the mothers that survived the productive period (40 weeks) and had high egg production and incubation quality, combined with high live weight and low feed consumption per unit of offspring growth.

Before being placed in the nests, the males were evaluated based on the external indicators of reproductive organ development, and individuals with inflammatory processes, underdevelopment, technical damage, etc., were culled.

The duration of the evaluation of the laying ducks in the breeding nucleus was at least 52 weeks. [[Q3: Q3]]). The breeding nests were filled with young birds every year. In the selection and selection of producers, inbreeding was excluded (Reuther and Kutushev, 2019; Korshukova et al., 2014). In addition, the phenotypic and genetic indicators of the main selected traits were studied.

In the course of the work, the following productivity indicators were studied:

• live weight and growth dynamics of young birds aged 1-7 weeks. Determined by weekly, individual weighing of the entire flock;

• live weight of adult birds was determined by random sampling of at least 10% of the total flock to control the growth and development of the birds;

• survival rate of young birds. The ratio of the surviving young birds to the original number of ducklings taken for rearing was determined (from 1 day to 7 weeks of age);

• the survival rate of adult birds. It was determined by the ratio of dead ducks to the number of ducks transferred to the adult flock, expressed as a percentage;

• sexual maturity. It was determined by the laying of the first egg for each egg-laying bird and for the entire line;

• egg production. It was calculated by the ratio of the total egg production over the entire period to the initial number of egg-laying birds;

• egg fertility. It was calculated by dividing the number of fertilized eggs selected by the ovoscope method by the number of eggs placed for incubation, and expressing it as a percentage.

• egg hatchability. It was calculated by dividing the number of healthy ducklings obtained by the number of fertilized eggs placed for incubation, and expressing it as a percentage.

• hatching rate. It was determined by dividing the number of healthy ducklings hatched by the number of eggs placed for incubation, and expressing it as a percentage.

2.2. Laboratory research methods

120 blood samples (40 from each cross) were used to describe the genetic structure of the “Kyzylzhar”, “Cherry Valley”, and “Ansar” duck breeds using DNA markers.

Blood was collected from the sub-wing vein using a disposable syringe (1-5 ml) or a special Venoject-type vacuum system (with EDTA). From the syringe, the blood was carefully (without foam formation) transferred to a disposable plastic Eppendorf tube containing one of the anticoagulants: 0.5 M EDTA solution (pH=8.0), in a volume ratio of 1:50 to 1:100 to the liquid blood; 3.8% Na citrate solution, in a volume ratio of 1:9 to the liquid blood. Heparin was not used as an anticoagulant, as it inhibits PCR.

The tube was closed, and the contents were gently mixed (by turning the tube over several times). The samples were stored in a refrigerator at +4°C for up to 60 days, and for longer periods, they were stored at –20°C. All collected samples were transported in a thermos with ice and were not subjected to repeated freezing/thawing.

We used the following laboratory equipment: an exhaust hood, a laminar flow hood, a 37°C thermostat, an Eppendorf-type microcentrifuge, a vortex, and a vertical chamber for polyacrylamide gel electrophoresis. Power supply, UV transilluminator, rubber gloves, safety glasses, set of reagents for DNA extraction and electrophoresis (synthesized by Syntol), 200-500 ml measuring cylinder, 96% cooled ethyl alcohol, distilled water, set of automatic pipettes (2-1000 μl), tips for automatic pipettes, 1.5 ml Eppendorf tubes (Holmes, 2001; Dahm, 2005).

2.2.1. DNA extraction method

DNA was isolated using the standard method of blood cell lysis with SDS-10% (sodium dodecyl sulfate C12H25NaO4S) in the presence of proteinase K and phenol-chloroform deproteinization followed by ethanol precipitation, as described (Instructions for use of the EXTRA-prep PS kit for DNA isolation from biological material, 2023).

The DNA samples were stored as an aqueous solution at -20°C. Total DNA was used to study polymorphic DNA loci.

2.2.2. Polymerase chain reaction (PCR) method for DNA synthesis

The initial PCR mixture was prepared in a volume of 25 μl:

• 60 mM Tris-HCl (pH 7.5);

• 10 mM((NH4)2SO4) 2804;

• 0.1% Tween-20;

• 100 mM of each of the four dNTPs 0.1 μM of primer;

• 20-25 ng of genomic DNA;

• 1 unit. Tag polymerases.

20 μl of light mineral oil was layered on top. The polymerase chain reaction was carried out in a “Tertsik” amplifier (Russia) for 30 cycles:

• 94°C – 1 min.

• 43°C – 1 min.

• 72°C – 1 min.

The amplification products were subjected to electrophoresis in a 7.5% polyacrylamide gel, stained with ethidium bromide, and detected under UV light. The DNA of the lambda phage hydrolyzed by PstI restrictase was used as a marker of molecular weights. (1501, 5077, 4749, 4507, 2838, 2556, 2459, 1986, 1700, 1159, 1093, 805, 514, 468, 339).

The image of the gels was recorded using a video system and the software “Infinity attached to it.1500/20M”.

The “Infinity-1500/20M” software consisted of: software for data evaluation and presentation; a 2-megapixel digital camera; a variable focal length lens (zoom); an F-590 filter; a CN-1500 dark room; a transilluminator with a 20 x 20 cm filter size and a power of 15 watts.

2.3. Statistical processing methods

Biometric and dispersion analysis of the data was studied using the method of variational statistics described in the works (Listratenkova, 2019; Burashkina, 2015; Gubina and Chupsheva, 2023).

When processing data on electrophoretic variants, the analysis of the obtained electrophoregrams was performed visually: all amplified bands that could be resolved, i.e., in the range of 1.7 to 20 tpn, were taken into account; bands that differed by less than 1 mm were considered identical. A binary data matrix of the “object-feature” type was compiled for each electrophoregram, where the presence of a band was denoted by “1” and its absence by “0”. Then, the percentage of polymorphism of the amplified DNA fragments (P%) and their occurrence frequencies (F%) were determined using the following formulas (Equation 1):

$$(\text{P\%})=\frac{\text{number of polymorphic loci}}{\text{total number of loci}}\times 100\text{\%}$$ (1)

Polymorphic loci were considered to be those that were found in the electrophoretic spectra of not all lines.

The frequency of occurrence (F) of locus A (an amplification fragment of a specific molecular weight) was calculated as Equation 2:

$$F=\frac{\text{number of lines that have locus}A}{\text{total number of lines}}$$ (2)

The arithmetic means (M±m) were calculated using the following formula (Equation 3):

$$\text{M}(или\overrightarrow{\chi })=\frac{\sum V}{n}=\frac{V_1+V_2+\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$4$}\right.+V_n}{n}\text{, где}$$ (3)

V – the value of the trait of each individual (variant);

n – the number of individuals in the group.

This indicator shows what value the trait would have if all the studied individuals were the same.

The average square deviations (σ), show how much each variant deviates from the average value squared. It is the scale of the variability of the trait, one of the most important indicators in further calculations, because it is used in the calculation of many indicators. If the average arithmetic value of a trait is the same for two groups of individuals, the value may be different. The standard deviation was calculated using Equation 4:

$$\sigma =\pm \sqrt{\frac{\sum {(V-\overline{X})}^2}{n-1}}$$ (4)

where V – variant; X – arithmetic mean; n – number of variants in the set.

Variation coefficients (variability) (Cv) allows you to compare the indicators of different signs, as it is measured in fractions of a unit or percentages. Shows the variability of the feature (Equation 5):

$$C\nu =\left(\sigma /M\right)*100\%$$ (5)

3. Results and Discussion

Based on “Bishkulskaya poultry farm” LLP (North Kazakhstan region, Kyzylzhar district, Beskol a.) carried out the selection of repair young cross “Kyzylzhar”, “Cherry Valley”, “Ansar”, and the acquisition of the parent flock in the ratio - 1:4 (1 drake per 4 hens), taking into account the established parameters of the selected features.

To test the fertilizing capacity of males, a control check was carried out, after which the identified defective were replaced with spares. Replacement – paternal line – 6 ducks; maternal line – 5 ducks.

The collection of hatching eggs from three crosses and the control laying for incubation were carried out, with an average egg weight of 88 g. During the incubation period, the laid duck eggs were ovoscoped (Tsarenko, 2016; Matrosova et al., 2024; Chugunova and Fedorova, 2025).

Ovoscopying (miraging) is a method of assessing the quality of an incubation egg and the development of the embryo. It is carried out using an ovoscope in darkened rooms. The procedure is necessary to discard eggs at the earliest stage (Dolgorukova et al., 2021; Umarov et al., 2022; Polina and Stepanova, 2022; Matrosova et al., 2024; Alpeisov et al., 2025; House et al., 2023). The results of the ovoscopic examination of duck eggs are presented in Table 1. The ovoscopy of hatching eggs and the rejection of unsuitable eggs are shown in Figure 1.

Table 1
Results of ovoscope examination of duck eggs (miraging).

Ovoscopy of duck eggs	Incubator Nº1 (“Kyzylzhar” cross)		Incubator Nº2 (“Cherry Valley” cross)		Incubator Nº3 («Ansar» cross)
	units	%	units	%	units	%
Miraging 1 (on the 8th day)
Unfertilized	162	8.1	77	3.9	87	2.0
“Blood Ring”	18	0.9	8	0.4	11	0.3
Miraging 2 (on the 13th day)
Bead-in-shell	118	5.9	116	5.8	113	2.7
Miraging 3 (on the 24th day)
Late dead	122	6.1	118	5.9	124	2.9
Lame ducks	76	3.8	84	4.2	81	1.9
Withdrawal	1518	75.9	1583	79.2	2155	48.2

Figure 1
Ovoscopy of an incubation egg a) ovoscopy of an incubation egg; b) egg rejection.

As a result of incubation, biological control was carried out for each batch during the control laying of the incubation egg, where the number of unfertilized eggs according to the “Kyzylzhar” cross was: unfertilized – 8.1%; blood ring - 0.9%; bead-in-shell – 5.9%; late dead - 6.1%; lame ducks – 3.8%; withdrawal - 75.9%, and according to the “Cherry Valley” cross: unfertilized – 3.9%; blood ring - 0.4%; bead-in-shell – 5.8%; late dead -5.9%; lame ducks – 4.2%; withdrawal – 79.2%, according to the “Ansar” cross: unfertilized – 2.0%, blood ring – 0.3%; bead-in-shell – 2.7%; late dead – 2.9%; lame ducks -1.9%; withdrawal – 48.2% (Figure 2, 3, 4).

Figure 2
Results of ovoscoping of duck eggs of the “Kyzylzhar”, “Cherry Valley”, and “Ansar” crosses.

Figure 3
Egg-laying intensity of “Kyzylzhar”, “Cherry Valley”, and “Ansar” ducks, % a) egg-laying intensity of ducks per initial duck; b) egg-laying intensity of ducks per average duck.

Figure 4
Egg-laying capacity of laying ducks of the “Kyzylzhar”, “Cherry Valley”, “Ansar” crosses, units a) egg-laying ducks per initial laying duck; b) egg-laying ducks per average laying duck.

The egg production of laying ducks was studied and analyzed during the laying period for the initial and average laying ducks, and the intensity of egg production was calculated, as shown in Table 2.

Table 2
Dynamics of egg-laying intensity and egg production in ducks.

Age, days	Cross
	“Kyzylzhar” (K12)		“Cherry Valley” (CV)		“Ansar” (A)
	the intensity of oviposition, %
	for the initial laying duck	for an average laying duck	for the initial laying duck	for an average laying duck	for the initial laying duck	for an average laying duck
196-226	66.5	66.7	66.3	66.5	66.4	66.6
227-256	84.8	86.7	90.0	91.6	87.4	89.15
257-286	80.2	83.7	84.4	86.8	82.3	85.25
287-316	78.7	83.1	81.3	84.6	80	83.85
317-346	76.2	83.7	87.6	92.5	81.9	88.1
347-376	74.1	85.6	87.1	82.8	80.6	84.2
377-406	69.1	82.6	81.0	87.5	75.05	85.05
407-436	65.5	81.0	76.8	83.6	71.15	82.3
437-466	61.0	78.3	77.1	84.2	69.05	81.25
196-476	72.3	81.0	81.0	85.4	76.65	83.2
egg production of laying ducks, units.
196-226	19.9	20.0	19.9	20.0	19.9	20
227-256	25.4	26.0	27.0	27.5	26.2	26.75
257-286	24.1	25.1	25.3	26.0	24.7	25.55
287-316	23.6	24.9	24.4	25.4	24	25.15
317-346	22.9	25.1	26.3	27.8	24.6	26.45
347-376	22.2	25.6	26.1	27.8	24.15	26.7
377-406	20.7	24.8	24.3	26.3	22.5	25.55
407-436	19.7	24.3	23.1	25.1	21.4	24.7
437-466	18.3	23.5	23.1	25.3	20.7	24.4
196-476	202.5	226.8	226.9	239.1	214.7	232.9

The average egg-laying intensity for the initial ducks was 72.3%, for the average ducks it was 81.0% for the “Kyzylzhar” cross, 81.0% and 85.4% for the “Cherry Valley” cross, and 76.65% and 83.2% for the “Ansar” cross, respectively. The average egg production of laying ducks in the second period of biological productivity, from 196 to 476 days of life, was 203 eggs per initial laying duck, 227 eggs per average laying duck, 227 eggs per initial laying duck, 239 eggs per average laying duck, and 215 eggs per initial laying duck, 233 eggs per average laying duck, respectively. The general dynamics of egg-laying intensity and egg-laying capacity of the “Cherry Valley” and “Ansar” crosses are shown in Figure 5.

Figure 5
General dynamics of egg-laying intensity (%) and egg-laying capacity of laying ducks (units) of the “Cherry Valley” and “Ansar” crosses: a) average egg-laying intensity; b) average egg-laying capacity of laying ducks.

The quality of day-old chicks was assessed based on their appearance. The assessment and weighing of day-old ducklings of the “Kyzylzhar”, “Cherry Valley”, and “Ansar” crosses are shown in Figure 6. The control over the preservation of young animals in the first days of rearing was satisfactory, and 3,101 heads were culled.

Figure 6
Daily young ducklings of the “Kyzylzhar”, “Cherry Valley”, and “Ansar” crosses: a) daily young ducklings in a brooder; b) evaluation of daily young ducklings by appearance; c) weighing of daily young ducklings.

An important indicator of poultry growth and development is the change in their live weight. The change in live weight was monitored every 7 days. The live weight was determined by individually weighing the young birds (Table 3). The dynamics of the live weight of young birds of the “Kyzylzhar”, “Cherry Valley”, and “Ansar” crosses are shown in Figure 7.

Table 3
Live weight of ducks up to 7 weeks (M±m).

Age, week.	“Kyzylzhar”	δ	Cv	“Cherry Valley”	δ	Cv	“Ansar”	δ	Cv
Daily allowance	0.078±0.0005	0.008	10.7	0.077±0.004	0.007	10.1	0.080±0.0002	0.011	13.8
1	0.216±0.0021	0.037	17.3	0.196±0.0021	0.036	18.3	0.203±0.0004	0.020	10.0
2	0.507±0.115	0.663	12.5	0.472±0.002	0.039	8.4	0.456±0.0007	0.029	6.47
3	0.875±0.075	0.130	14.9	0.808±0.009	0.147	18.3	0.834±0.0005	0.022	2.66
4	1.393±0.009	0.193	10.7	1.427±0.011	0.193	13.5	1.228±0.0010	0.043	3.60
5	1.797±0.011	0.193	10.7	1.822±0.013	0.228	12.5	1.865±0.0008	0.035	1.94
6	2.378±0.024	0.422	17.7	2.403±0.026	0.457	19.0	2.291±0.0013	0.052	2.27
7	2.702±0.016	0.274	10.1	2.857±0.012	0.214	7.5	3.249±0.0014	0.055	1.74

Figure 7
Dynamics of live weight of young birds of the “Kyzylzhar”, “Cherry Valley”, and “Ansar” crosses.

The dynamics of ducklings’ live weight during the 7-week rearing period shows that the “Kyzylzhar” cross surpassed the “Cherry Valley” cross in terms of growth and development up to 3 weeks of age, but from 4 weeks of age until slaughter (7 weeks), it lost 155 g in weight, resulting in 2.702 kg and 2.857 kg, respectively. The live weight dynamics of the “Ansar” cross throughout the entire period of control weighing from 1 day of age to 7 weeks is higher than that of the “Kyzylzhar” and “Cherry Valley” crosses.

The analysis we conducted showed that as a result of purposeful breeding work, there has been an annual improvement in the productive and reproductive traits of the “Ansar” cross ducks. The productivity indicators of ducks of the “Kyzylzhar”, “Cherry Valley”, and “Ansar” crosses are presented in Table 4. Table 4 shows that as a result of purposeful selection, the live weight of the “Ansar” cross ducks increased by 689.8 g and the hatchability increased by 7.3% compared to the “Kyzylzhar” cross ducks. It should be noted that the selection of ducks of the mother line aimed at increasing the fertility provided for the selection not only by the number of eggs laid by the duck, but also by their suitability for incubation. In this regard, targeted selection was carried out to increase the yield of eggs suitable for incubation, increase the fertilization of eggs and their hatchability.

Table 4
Productivity indicators of ducks of the parent breeds “Kyzylzhar”, “Cherry Valley”, and “Ansar”.

Indicator	Cross
	“Kyzylzhar”	“Cherry Valley”	“Ansar”
Egg production per initial duck, units.	214.65	233.0	232.9
Average egg weight, g	88	87	90
Adult ducks survival rate,%	94.6	95.1	96.4
Hatching eggs yield,%	75.9	79.2	77.5
Egg hatchability, %	83.1	83.4	90.4
Egg fertility, %	91.5	95.7	92.2
Ducklings rearing rate, %	75.9	79.1	71.4
Live weight of ducks at 7 weeks, kg	2703.7	2857.4	3393.5

In the subsequent breeding work, this group became the main one for breeding a new domestic duck breed on the basis of the “Bishkulskaya poultry farm” LLP, which is located in the North Kazakhstan region.

A mutation of the type of loss (deletion) or rearrangement (inversion) of one or more nucleotides that has arisen in the eggs of the maternal organism can be detected in the mtDNA of the offspring during its restriction analysis. The latter is quite feasible, as the structure of mtDNA is well-studied, and many species have been sequenced (the nucleotide sequence in DNA is known).

However, in some individuals of certain species of wild and domestic animals, as well as in humans, polymorphism in the length of restriction fragments of mtDNA is found, i.e. sometimes the length of fragments may differ from the usual one. This is due to the restructuring of DNA at the places of its cutting by restriction enzymes. The latter, in turn, is the result and evidence that a mutation has taken place (Zubov and Kashevarov, 2011; Krivoruchko et al., 2021). Currently, DNA polymorphism studies are being conducted in many natural and some agricultural populations, which significantly increases the possibilities for studying microevolutionary processes in animal and bird populations.

The main type of polymorphism for RAPD markers is the presence or absence of an amplicon (band) on the electrophoregram. A number of authors also consider the intensity of manifestation (majority - minority) of the corresponding amplicons as polymorphism (Ganieva, 2007; Ulimbashev et al., 2018).

If the structure in which the mutation occurred is unique, then the band is completely absent. If this structure is represented by repeats, then mutations in one or even several copies should not cause the band to disappear, but only affect its intensity. Major bands appear as a result of more specific annealing of universal primers. A small insertion or deletion of a fragment in the interior of the amplification product would result in a change in the size of the amplicon (Diyaware et al., 2017; Szemethy et al., 2021).

Whatever the appearance of the described types of polymorphism, in the end they lead to a specific, purely individual genomic fingerprint, as a rule, reproducible upon repeated amplification.

It should be emphasized that the selection of primers for RAPD-analysis of the genome of various taxonomic groups in each specific case should be carried out strictly individually, since the obtained amplification pattern depends not only and not so much on the nucleotide sequence of the primers, but rather on the primary structure of the DNA of the species and breeds under study.

In the studies, 6 oligonucleotide primers (N) with several nucleotides from 10 to 16 were used to identify interlinear differences in ducks that make up the zonal population of “Bishkulskaya poultry farm” LLP (P1(1510) - AGTCAGCCAC; P2(1509) - TGCCTAGCTG; P3(1512) - GAGGGTGGCGGTTCT; P4(1513) - CCGGCCTTAC; P5(HM13) - CACAATTCCACACAAC; N6(RM13) - AACAGCTATGACCATG).

Figure 8 shows the electrophoregrams of the DNA amplification products of the studied ducks with the P5-HM13 primer.

Figure 8
Electrophoregrams of duck DNA amplification products. “Bishkulskaya poultry farm” LLP with primer P5 - HM13: a) “Kyzylzhar” cross, b) “Cherry Valley” cross, c) “Ansar” cross.

Electrophoregrams show that each of the studied lines of Peking ducks has its own characteristic amplification profiles. As a result of the analysis of the DNA samples of all the studied duck crosses, the number of fragments amplified using this primer ranges from 7 to 14 in the “Kyzylzhar” cross, from 3 to 7 in the “Cherry Valley” cross, and from 4 to 12 in the “Ansar” cross, with varying degrees of staining intensity.

Genetic distances were calculated based on the results of amplification profiles with different primers and biometric processing of the obtained data.

As a result of biometric processing, it was found that the “Kyzylzhar” and “Ansar” crosses are closer to each other by a coefficient of genetic distance with primer P5 - HM13: 0.957 than the “Cherry Valley” crosses - 0.806. According to the results of laboratory studies, the three groups of ducks with different color intensities represent an almost single undifferentiated population, whose subpopulations are genetically They are equidistant from each other (the genetic distance between the “Cherry Valley” and “Ansar” subpopulations is 0.855, and between the “Kyzylzhar” and “Ansar” subpopulations is 0.930.

The study of the genetic structure of cross-breeding lines using the RM13 primer showed that the number of amplified fragments ranges from 6-14 in the “Cherry Valley” cross-breeding line to 13-23 in the “Kyzylzhar” and “Ansar” cross-breeding lines. In the “Ansar” cross-breeding line, additional fragments were observed in the region below the 805 bp marker band. In general, the lines differ not only in the number of fragments but also in their arrangement.

The result of calculating genetic distances showed that the crosses “Kyzylzhar” and “Ansar” are the least distant from each other, and therefore the most homogeneous (the coefficient of genetic similarity is 0.839), which means that they have a higher genetic similarity than the crosses “Cherry Valley” – “Kyzylzhar” (0.494) and “Cherry Valley” – “Ansar” (0.656).

In terms of absolute value, these figures are somewhat different from the similarity indices obtained using the HM13 primer. However, when constructing a dendrogram, they provide a very similar picture of the subordination of the samples.

The RAPD spectra of the families obtained using the HM13 primer can be explained by both the inheritance pattern of the bands and the genetic recombinations that occur during the process of crossing over. From a molecular perspective, genetic recombinations are based on the process of interaction and exchange between homologous fragments between two DNA molecules. This process is known to result in up to four recombinant chroms.

Industrial populations of farm birds are a good model of the breed-forming and microevolutionary processes that occur in them under the condition of strong pressure of artificial selection.

The process of creating new lines and the formation of certain desirable traits in them is always associated with the transformation of the initial genetic material. There is an opinion that genetic recombinations do not create anything new, but serve only to recombine the existing genes. The biological significance of recombinations is the combination of differently specialized genes in one organism, and in the molecular sense, the concepts of mutation and recombination reflect the same thing - changes in the primary structure of DNA molecules. These changes can be detected using RAPD markers, and our research has shown that they are the driving force behind microevolutionary and formative processes that occur under the influence of selection.

Since the degree of heterosis directly depends on the degree of genetic differences between the crossed parents (Bekenev, 2023), it seems reasonable to try to obtain hybrid offspring from the crossing of the “Ansar 1”, “Cherry Valley 2” and “Ansar 2”, “Cherry Valley 1” crosses, which, as our research has shown, differ from each other to a greater extent than the “Kyzylzhar” cross lines, to increase the compatibility of productivity traits and obtain a greater heterosis effect.

The studies were conducted at the “Bishkulskaya poultry farm” LLP, which is located in the northern region of Kazakhstan. The main meteorological parameters considered are shown below (Figures 9 and 10).

Figure 9
Average meteorological indicators in northern Kazakhstan during the spring-summer period (2025).

Figure 10
Average air temperature in northern Kazakhstan during the spring-summer period (2025).

The climate of the North Kazakhstan region is sharply continental. Summers are dry and hot, while winters are harsh and freezing. The region’s location in the interior of the Eurasian continent, its distance from the oceans and sea basins, its relatively high latitude, and the orographic openness of the territory from the north and south all contribute to the formation of its climate. The sharp continental nature of the climate is characterized by significant fluctuations in air temperature throughout the year and across different seasons, as well as throughout the day. The air temperature in the warmest month (July) is almost everywhere 18°C, and in the coldest month (January) it ranges from -16°C in the south to 18°C in the northeast of the region. The maximum temperatures in the year reach 41°C, and the minimum temperatures reach 48°C. There are significant fluctuations in temperature throughout the day, especially in spring and autumn, when warm and even hot days are often followed by very cold nights. The average duration of the warm period with temperatures above zero is 200 days in the region (210 days in Chkalovo). Frequent cyclonic activity results in a relatively high amount of precipitation. The average annual precipitation in most parts of the region is 340 mm, but it is less than 300 mm in the west and southeast, and more than 350 mm in the north. Most of the precipitation occurs during the warm season (April-October). Strong winds are common in the region. The average wind speed is 5 m/s, but there are also winds with speeds of 10-15 m/s. The wind tends to strengthen in the spring. The prevailing wind direction is south-western, especially during the winter.

The average air temperature in the northern region of Kazakhstan in the spring of 2025 was as follows: in March, daytime: 0 °C; at night: -6 °C; in April – during the day:+14°C; at night: +7°C; in May – during the day:+18°C; at night: +11°C (Kazhydromet Kazakhstan, 2025; Munaitpassova et al., 2025).

4. Conclusions

The results of our research and analysis confirm that the targeted selection of “Ansar” ducks leads to an annual improvement in their productive and reproductive qualities. In particular, “Ansar” ducks outperform the “Kyzylzhar” cross in terms of live weight (by 689.8 g) and hatchability (by 7.3%).

Comparative data show that Ansar (232.9 units) is comparable to “Cherry Valley” (233 units) and surpasses “Kyzylzhar” (214.65 units) in egg production. The average weight of eggs at “Ansar” is the highest – 90 g. “Cherry Valley” leads the way in hatching eggs (79.2%), followed by “Ansar” (77.5%) and “Kyzylzhar” (75.9%). The fertility rate of “Cherry Valley” eggs is also higher (95.7%), while that of “Ansar” and “Kyzylzhar” is 92.2% and 91.5%, respectively. However, in terms of duckling production, “Ansar” (71.4%) is inferior to “Cherry Valley” (79.1%) and “Kyzylzhar” (75.9%).

Genetic analysis using the P5-HM13 primer showed that the “Kyzylzhar” and “Ansar” crosses are genetically closer to each other (coefficient of 0.957) than to “Cherry Valley” (0.806). Laboratory studies also confirm that these three groups of ducks, despite their differences in coloration, represent a genetically close population, with the “Cherry Valley” and “Ansar” subpopulations (0.855) and the “Kyzylzhar” and “Ansar” subpopulations (0.930) being genetically equidistant.

A study of the genetic structure with the RM13 primer revealed a greater number of amplified fragments in “Kyzylzhar” and “Ansar” (13-23) compared to “Cherry Valley” (6-14). “Ansar” also has unique additional fragments. In general, the lines differ in both the number and location of the fragments.

The calculation of genetic distances confirms that “Kyzylzhar” and “Ansar” are the most genetically similar (coefficient 0.839), which is significantly higher than the similarity between “Cherry Valley” and “Kyzylzhar” (0.494) or “Cherry Valley” and “Ansar” (0.656).

Given that heterosis depends on genetic differences, we suggest crossing the “Ansar 1” cross with the “Cherry Valley 2” cross and the “Ansar 2” cross with the “Cherry Valley 1” cross. According to our data, these combinations have greater genetic divergence than the “Kyzylzhar” cross, which may lead to a more pronounced heterosis effect and improved productive traits.

Since the greater the genetic differences between the parents, the greater the heterosis effect (improved productivity in hybrids), we believe that it is advisable to obtain hybrid offspring in order to achieve maximum effect and improve productivity. We propose crossing the “Ansar 1” cross with the “Cherry Valley 2” cross and the “Ansar 2” cross with the “Cherry Valley 1” cross. Our research has shown that these combinations have greater genetic dissimilarity compared to the “Kyzylzhar” cross lines. After obtaining the hybrids, it is necessary to test their productivity.

An analysis of the climate data of the North Kazakhstan region, where the “Bishkulskaya poultry farm” LLP is located, revealed the following trends. The average annual air temperature shows a steady increase, especially noticeable in spring and summer. In general, the temperature increases from north to south of the region, ranging from 2.4 to 3.6°C. The climate of the region is continental. Spring begins between April 2 and 4 and lasts for about 1 month and 10 days. Summer comes from May 18 to May 25 and lasts for a little over 3 months. Autumn begins in late August – early September and lasts for a little less than 2 months. Winter comes from October 25 to October 29 and lasts for more than 5 months (from November to March).

The stable temperature transition through 5 °C occurs on April 13-14, through 10 °C on April 29-May 2, and through 15 °C on May 18-25. There is a gradual increase in the heat supply during the growing season. The last spring frosts usually end on May 10-14, and the first autumn frosts begin on September 18-22. The climate of the region is considered moderately favorable: summer is favorable, spring and autumn are moderately favorable, and winter is moderately unfavorable. These climate data are of great importance for the scientific support of agricultural activities. They will help in the development of climate-adapted technologies, the more efficient use of the region's climate resources in research and practice. The information obtained will allow for the reasonable planning and implementation of agricultural activities at the optimal time, as well as the development of strategic plans for the development of the base farm where research on waterfowl is conducted.

Acknowledgements

The authors express their gratitude to “Bishkulskaya poultry farm” LLP for providing access to waterfowl and their assistance in scientific research, represented by the director of the base farm, Bilyalov S.S. These studies were conducted as part of the scientific and technical program “Development of effective methods for breeding waterfowl using breeding and technological methods and information technologies” BR22887152 for 2024-2026, funded by the Ministry of Agriculture of the Republic of Kazakhstan through program-targeted financing.

Data Availability Statement

Research data is available in the body of the article.

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Edited by

• Editor:
  Takako Matsumura Tundisi

Publication Dates

• Publication in this collection
  31 Aug 2026
• Date of issue
  2026

History

• Received
  05 May 2026
• Accepted
  29 June 2026