Nikita S. Kolesnik

Including rapeseed in broiler diets increases protein levels without increasing feed volume. However, anti-nutritional components of rapeseed can affect blood morphological parameters: glucosinolates suppress thyroid function, indirectly affecting erythropoiesis, while phytic acid impairs the absorption of iron and copper, which are necessary for hemoglobin synthesis. Therefore, this analysis is necessary to assess the physiological state of birds when adding rapeseed at various doses. The aim of this study was to examine blood morphological parameters after replacing specific protein components in the broiler chicken diet. A 10 % feed replacement did not significantly alter blood morphological composition; basophil counts decreased by 20,7 %, which may positively impact the immune status of broiler chickens. Replacing 25 % and 50 % of the feed weight with rapeseed in the diet resulted in a 41,2 % and 32,3 % reduction in white blood cell counts, respectively. However, these values are within reference limits and therefore cannot be considered a symptom of abnormalities. Eosinophil counts increased in experimental groups 3 and 4 by 48,1 % and 36,4 %, respectively, which remains within physiological norms and can only indirectly indicate an inflammatory process in the bird’s body. To develop practical recommendations for feeding broiler chickens with rapeseed supplements at various dosages, a comprehensive assessment of morphological parameters, blood biochemistry, and chyme analysis is necessary.

Broiler meat is an important source of protein with a balanced essential amino acid profile; however, the environmental stress associated with a high stocking density can reduce its nutritional value. Adaptogen supplementation represents a promising strategy to mitigate this negative impact. This study aimed to evaluate the amino acid composition of the breast and thigh muscles of Smena-9 broiler chickens under a high stocking density and dietary supplementation with an adaptogens complex (dihydroquercetin + vitamins E and C). The experiment was conducted on 120 broilers allocated to four groups: recommended stocking density (negative control), high stocking density (positive control), high stocking density with adaptogens from day 21, and high stocking density with adaptogens from day 1 of the experiment. The stocking density changed as the bird grew. On day 21, the bird stocking density in the S(-)CON group was 38 heads per 1 m², in the other groups it was increased by 10% and amounted to 42 heads per 1 m². Each week, the stocking density changed and amounted to 32 and 35 heads per 1 m² in 28–35 days, 21 and 23 heads per 1 m² in 35–42 days, and 17 and 19 heads per 1 m² in 43 days and until the end of fattening, respectively. The amino acid profile was determined by ion-exchange chromatography with post-column derivatization using ninhydrin. Age was the primary factor influencing the amino acid composition, followed by muscle type and stocking density. Sex-related effects were less pronounced and were observed at 24 days of age. Breast meat exhibited higher amino acid content than thigh meat (82.4–89.9 vs. 65,8–77.8 g/100 g dry matter for total amino acids, respectively). Under a high stocking density, the most notable changes were observed in the thigh muscle at early ages. By day 52, the birds receiving the adaptogen complex from day 1 showed an increase in the sum of essential amino acids in the breast meat (+2.4%, p < 0.05), with the most pronounced improvements observed for methionine (+5.9%, p < 0.001) and lysine (+3.9%, p < 0.05) compared with the recommended-density control group (S(-)CON). Additionally, early adaptogen administration preserved the levels of flavor-related amino acids between days 34 and 52, whereas a decline was observed in other groups, indicating maintained sensory quality with age. Thus, the early administration of the adaptogen complex appears to mitigate for high stocking density negative effects and contributes to preserving the nutritional value of broiler meat, although the underlying mechanisms remain hypothetical and require further.

A protein with a balanced amino acid composition is a key element in poultry feeding, necessary for intensive growth and high productivity. Deficiency of limiting amino acids (AA) in the diet inevitably leads to metabolic disorders, slower growth rates and a decrease in the productive qualities of poultry. Rapeseed proteins are well balanced in amino acid composition; in lysine content they are close to soybeans, and in methionine and cysteine, calcium and phosphorus they are significantly superior to it. The aim of this work is to evaluate the effect of replacement of some feed with rapeseed in the amount of 25-75% of the broiler chicken diet on the amino acid profile of the body. The experiment involved 4 groups of fistula broiler chickens of the Smena 9 cross (N = 20, n = 5): 1 (k) - basic diet (BD) + crude fat (CF) 5%; 2 (o) - BD + 25% rapeseed (RS) (9.5% CF); 3(o) – OR with 50% RS (19% CF); 4(o) – OR with 75% RS (28.5% CF). Amino acid analysis of blood serum was performed by ion-exchange chromatography with post-column derivatization with ninhydrin. The introduction of rapeseed into the broiler diet contributed to a reliable (p≤0.05) increase in the content of Val, Gly, Ser in the blood of chickens from the experimental groups, as well as a marked increase in the level of Arg, Ala, Cys, Met and Lys. The 2nd group is characterized by the highest content of a number of functional amino acids: Asp, Thr, Ser, Glu, Gly, Ala, Val and Leu, however, the ratio of the sum of essential AAs to replaceable AAs was the best in the 4th group, which is due to the high content of Met, Ile, His, Lys and Arg along with a lower concentration of a number of replaceable AAs. Thus, replacing the grain portion of the broiler chicken diet with rapeseed in an amount of 25-75% has a pronounced effect on the overall amino acid profile of the blood.

T o stu d y t he effe ct o f a newly developed adaptogenic complex on the chemical composition of muscle and bone tissues, as well as on the quality and process characteristics of the broiler chickens breast and thigh muscles, an experiment was conducted on 3 groups of the broiler chickens in the physiological ward of the Federal Research Center for Animal Husbandry named after Academy Member L. K. Ernst (n = 40, N = 120) (1 control group and 2 experimental groups) under conditions of increased stocking density. The poultry from the experimental groups received the DHQEC complex with their diet (the 2 ^nd experimental group started receiving it from the 22 ^nd   da y o f lif e, i.e., fr om t he da y o f t he o ns e t o f si m ul a t ed o vercr o w ded envir o n m ent a l c o n d iti o ns; t he 3 ^{r d} experi m ent a l gr o up st a rt ed r e c ei ving it fr om t he 7 th   da y o f t hei r lif e). On the day 34 ^th (n = 10, N = 20) and 52 ^nd   (n = 10, N = 20) of age, the samples of the breast and thigh muscles and the tibia bones were collected. The chemical composition, as well as several quality and process properties of the meat were determined. The administration of DHQEC for 34 days of the poultry life contributed to an increase in fat content in the breast muscle from 0.74 % in the control group up to 1.03 % and 1.17 % in the experimental groups, respectively; an increase in the pH of muscle tissue; an increase in the water-holding capacity (WHC) of the breast (p < 0.01) and thigh (p < 0.01) tissues; and elevated levels of reduced glutathione (at p < 0.05 and p < 0.01) and superoxide dismutase (at p < 0.01) compared to the control group values. In the liver of the poultry that received DHQEC, an increase in the level of water-soluble antioxidants was observed, whereas in the cardiac muscle, conversely, a decrease was noted. At the 52 ^nd day of age, the trend of differences between the groups persisted. A significant difference was found in phosphorus content (it was lower in the control group) (p < 0.05) and magnesium content (it was lower in the 3 ^rd   experi m ent a l gr o up) (p < 0.05), which may be associated with the impact of stress and its mitigation by the DHQEC complex. The most pronounced effect of the complex was observed when it was introduced into the diet from the 7 ^th   da y o f t he p o ultry lif e. Th e ob t a in ed da t a o p en b r oad pr o sp e cts f o r t he inclusi o n o f t he DHQEC c om plex int o b r o iler c h ic k en die ts, p a rticul a rly d uring p eriod s o f str e ss exp o sur e fr om t he first da ys o f lif e.

Downy goat breeding in Russia is represented by small-numbered breeds with a limited range, and in the current conditions they are on the verge of extinction, especially the population of the Orenburg goat breed is in critical condition. Current scientific research of Orenburg goats continues to the present time, which indicates the presence of scientific and practical interest in this breed. This review presents the current global and domestic state of goat breeding. Special attention is paid to the problems and development of down goat breeding in the Russian Federation, as one of the commodity branches of agricultural production. Information about the unique native Orenburg breed of downy goats is presented. The history of the creation and breeding of the breed, the main directions of productivity and the external indicators of animals are considered. The inbreeding characteristics of Orenburg goats are given, down quality indicators are considered, and the results of genotyping the modern gene pool of the Orenburg goat population are presented. Attention is paid to the technology of combing the down of Orenburg goats. The article presents studies on the elemental, amino acid composition of the wool and down of Orenburg goats over the past five years. At the same time, when preparing the review, there is a lack of research in the field of the influence of normalized diets of Orenburg goats on scar and intestinal digestion, physiological status, intensity of growth and development of young animals. This work presents a summary of the latest economic, scientific, research and practical knowledge about the current state, problems and trends in the preservation of the Russian downy Orenburg goat breed, as one of the exceptional gene pool populations preserved in Russia.

The purpose of this work is to conduct comprehensive studies aimed at studying the effect of modulated stress of cage density in the poultry houses on the body of domestic cross-breed of the broilers “Smena-9”, in particular -on the chemical composition, some qualitative characteristics and antioxidant status of their muscle tissue. An experiment was conducted in the conditions of the physiological yard of the Federal Research Center for Animal Husbandry named after Academy Member L. K. Ernst in 2023 on 2 groups of the broilers (n = 40, N = 80) (control group and experimental group) of the domestic cross-breed of the broilers “Smena-9”. The control group was kept under the conditions of the cage density recommended for this cross-breed (Stress-). The poultry cage density in the experimental group (Stress +) was increased by 10 % from the 21st day of the poultry's life in order to create stress conditions. To study the effect of modulated stress on the composition and quality of meat, we conducted poultry slaughterings at the age of 24 (n = 10, N = 20), 34 (n = 10, N = 20) and 52 (n = 10, N = 20) days. Stress led to significant changes in the pH of the breast flesh: 45 minutes after slaughter, the index was 5.55 versus 5.59 units (p = 0.004), and 24 hours later — 5.44 versus 5.60 units. (p = 0.08). The values of the WHC of the experimental group were also lower than those in the control group on the 34^th and 52^nd days. The stress factor under study was not critical for the development of acute oxidative stress; the greatest changes were observed in age dynamics. There is a decrease in the pH of the breast flesh depending on the age aspect (p < 0.05) in both groups. On day 52, there was a significant (p < 0.01) decrease in TAC content in the breast of poultry of both groups, in the heart muscle in the control group (p = 0.06) and the experimental group (p < 0.001), there was an increase in the activity of SOD and catalase. The data obtained will allow the development of ways to regulate the quality of poultry products.

A comparative intergroup analysis of fattening pigs of different breed and age groups according to biochemical and amino acid parameters of blood serum was carried out. When forming groups based on the principle of analogues, n = 10 heads of animals were selected in each group: 1 – Landrace 60-65 days of fattening; 2 – Landrace x Large White 60-65 days of fattening; 3 – Landrace 100-110 days of fattening; 4 – Landrace x Large White 100–110 days of fattening. Pairwise intergroup comparisons were performed after checking the distribution of data according to the Shapiro-Wilk criterion and evaluating the uniformity of variance using the Levene’s test. Univariate variance analysis and the Tukey-Kramer test were used for data where the distribution corresponded to normal, and the condition of uniformity of variance in groups was confirmed. If one of the two conditions is not met, the comparative analysis is performed using the Kruskal-Wallis test with the Bonferroni correction, in combination with the Mann-Whitney test. No statistically significant differences were found in groups 1 and 2. With age, for groups 3 and 4, significant differences were found only for amino acids – methionine and valine. in Landrace breed (group 3) on the 100-110^th day of fattering the content of the following amino acids in the blood was significantly higher: aspartic acid (p = 0.014), glutamic acid (p = 0.042), isoleucine (p = 0.035), cysteine (p = 0.003), alanine (p = 0.035), serine (p = 0.013), valine (p = 0.006), arginine (p = 0.001) in comparison with the animals of the 1 group; whereas the average values for the methionine index were lower (p = 0.008). In Landrace x Large White hybrids (group 4) on the 100-110th day of fattering the content of total protein (p = 0.015), albumins (p < 0.001), urea (p = 0.008), aspartic acid (p < 0.001), alanine (p < 0.001), isoleucine (p = 0.003), lysine (p = 0.001), cysteine (p = 0.002), valine (p < 0.001), arginine (p < 0.001) was higher while the content of proline (p = 0.028) and methionine (p < 0.001), serine (p < 0.001), glycine (p = 0.003) was lower in comparison with the animals of the 2 group. Thus, the change in biochemical parameters and amino acid composition of pig blood is mostly influenced by age dynamics that is more vividly manifested in hybrids compared with the pure breed.

In the last decade, significant progress has been achieved in pork production and Russian pig farming in general. However, it is necessary to intensify work on establishing standards for the main biochemical (BC) parameters of the blood of commercial pig hybrids, which was the main goal of the work. The studies were conducted on boars of the following groups: 1) Duroc breed on the 60-65th day of fattening (n=12), 2) F2 Duroc˟Landrace˟Large White hybrids on the 60-65th day of fattening (n=19), 3) Duroc breed on the 100-110th day of fattening (n=18) and 4) F2 Duroc˟Landrace˟Large White hybrids on the 100-110th day of fattening (n=27). Blood samples were taken from the ear vein into vacuum tubes with a blood coagulation activator for biochemical coagulation analysis and centrifuged (15 min at 3000 rpm). Biochemical coagulation analysis was performed on a ChemWell analyzer (Awareness Technology, USA). Amino acid concentrations in blood serum were determined by ion-exchange chromatography on a HPLC LC-20 Prominence (Shimadzu, Japan) with a proprietary column and a module for post-column derivatization with ninhydrin ARM-1000 (Sevko&Co, Russia). Samples for analysis were prepared according to GOST 32195-2013. It is positive that the main protein indices of blood in Duroc pigs and their F2 hybrids in different age groups are quite stable, as evidenced by low and moderate variation coefficients (CV<20%). It is shown that with an increase in the fattening period, the tendencies to intensify all types of metabolism increase, as evidenced by numerous correlations between the biochemical and amino acid parameters of blood of boars of groups 3 and 4 at the end of fattening (100-110 days) compared to groups 1 and 2 (a period of 60-65 days). The authors believe that establishing relationships between the biochemical parameters of pig blood, on the one hand, and their breed characteristics and fattening duration, on the other hand, is of great fundamental and practical importance.

The article presents the results of a study of the effect on digestion processes and methane emissions in sheep when fed phytogenic feed additives based on condensed tannins of Lárix dahúrica and their complex with dihydroquercetin.The experiment was conducted at the physiological yard of the L.K. Ernst Federal Research Center for Animal Husbandry and Animal Welfare on Romanov sheep with chronic rumen fistulas according to Basov. The experiment was conducted using the 2 × 3 Latin square method (n = 6). In the first period, the sheep received a hay-concentrate diet containing 40% concentrates by nutritional value. The dosage of tannins was 5 g/head per day, dihydroquercetin — 0.1 g/head per day. At the end of each balance experiment, rumen contents were sampled from all animals (n = 6) to determine rumen digestion indices.When feeding the studied additives, a tendency to increase amylolytic activity in the experimental groups is observed. In the control, this indicator was 17.403 U/ml, in the first experimental group — 18.128 U/ml, in the second — 18.423 U/ml. The amount of VFA significantly (p < 0.05) increased when consuming the complex additive (tannin + DHQ) — 9.137 mmol/ml versus 8.385 mmol/ml in the control. These data correlate with an increase in symbiotic microflora (both bacteria (p = 0.013) and ciliates) relative to the control in the third group (tannin + DHQ) and a decrease in the second. When feeding only tannin, the level of ciliate formation was lower and the concentration of VFA after feed intake was lower. This indicates the inhibition of microflora under the influence of tannin. At the same time, the synergistic effect of the action of Lárix dahúrica tannins and DQV on the intensification of rumen digestion processes is demonstrated. There is a decrease in methane release by 14.8% when consuming tannins, and by 26.8% when consuming a complex additive, which indicates the presence of synergy in the effect of the studied additives on methanogenesis in sheep in vivo.

Amino acids (AA) are the important markers of the state of protein metabolism, and therefore the study of the amino acid composition of animal tissues is an urgent task. This article presents the results of amino acid analysis of the blood serum of fattening pigs of the Landrace breed and twobreed hybrids (Landrace·Large White) depending on the duration of fattening. Fattening pigs (n=40) were divided into 6 groups depending on the breed and duration of fattening: A-2 – 60 days of fattening Landrace pigs, B-2 – 60 days of fattening F1 Landrace Large White, C-2 – 70- 80 days of fattening a Landrace pig, D-2 – 70-80 days of fattening F1 Landrace Large White, F-2 – 100 days of fattening a Landrace pig, S-2 – 100 days fattening F1 Landrace Large White. The most stable amino acids in blood levels are tyrosine, histidine, threonine, phenylalanine, glycine and proline in all studied groups of animals. According to the results obtained, changes in the AA composition of blood serum are largely due to the duration of fattening (as a one of the key feed factors) and the genotypes of animals.