The major sources of rough feed production in Yakutia are native hayfields and range lands, which provide 85 % of all feed. Natural grasslands and range lands occupy extensive grounds – 1.4 million hectares, of which 740 thousand hectares are hayfields and 670 thousand hectares are range lands. Grasslands of Yakutia are economically the most important source of sup-porting the agricultural sector and the livelihoods of the local population. The article analyzes the developed agritechnologies for improving grass and range lands of Yakutia and substantiates promising energy-saving methods for yield enhancement during land reforms. Currently, the research on the improvement and restoration of grass and range lands is focused on energy-saving, the use of renewable local resources and the biologization of grassland culture in order to increase the productivity and bulk feed quality. The analysis of the northern grassland culture development during the intensification has shown that the development of own seed multiplication system of released varieties and species of legume grasses makes it possible to introduce successfully energy-saving agritechnologies. The article proposes various methods of energy-saving in agritechnologies, such as: application of organic fertilizers, use of the released local varieties and species of perennial grasses, increase in the area of legume-grass plant formations for improving the feed quality and the use of multiple-function agricultural equipment for cost saving.

To improve the breed characters of farm animals, there is the need for breeding based on reliable information about the particular breed of animals, which is the key to high-quality breeding work. In this regard, there is a need to search for new methods of reliable identification of the breed of animals. The article presents an analysis of methods based on the achievements of modern genetics, which are used to obtain more accurate information when determining the breed of ani-mals. A brief description of methods for determining the species and breed identification of animals based on molecular DNA markers is given. Methods based on the study of polymorphism of mitochondrial DNA and microsatellites are analyzed. Spe-cial attention in this review is paid to the latest and most promising achievements in the field of high-performance genotyping technologies based on single nucleotide polymorphism (SNP). The analysis of the literature sources has shown that each breed of farm animals is characterized by its unique genetic structure, which should provide an objective result when deter-mining the breed of the animal.

Search and introduction of new potato varieties that can be recommended for cultivation in soil and climatic conditions of the Komi Republic are especially important against the background of the average yield in the region of 12.1 t/ha, that is 6.7 t/ha lower than the average in Russia. In 2019-2020 on the basis of the A. V. Zhuravsky Institute of Agrobiotechnology of the Federal Research Center of the Komi Scientific Center of the Ural Branch of the Russian Academy of Sciences, there were tested potato varieties of the early maturing group – Armada, Meteor, Gulliver, Taifun and Krepysh (standard) and the mid-season group – Varyag, Vympel, Krasa Meshchery, Kumach, Fritella, Vychegodskii and Zyryanets (standard). From the early maturing group, the varieties Armada and Gulliver have been selected as giving a consistently high yield, which exceeded the standard by 6.8-7.1 t/ha on average for two years. Among mid-season varieties no one reliably exceeded the standard variety Zyryanets in terms of yield productivity. The highest yield and marketability was noted for the Fritella variety – 30.5 t/ha and 97 %. All the varieties under study, except for Vychegodskii, showed an average resistance of the tops to late blight damage. Moderate early blight damage of the tops (up to 20 % of the leaf surface) was noted in three varieties – Meteor, Taifun and Vychegodski. The following varieties showed high resistance to common scab - Vympel (no damage), Zyryanets (few lesions) and Gulliver (up to 10 % of tuber surface damage). In all studied varieties the potato tubers were not affected by late blight during both years of research. For cultivation, the agricultural producers of the Komi Republic should use the varieties Armada (29.7 t/ha), Gulliver (28.1 t/ha), Vympel (29.2 t/ha), Fritella (30.5 t/ha), which have good resistance to phytopathogens and high quality of tubers.

The genotypes of potatoes bred by Falenki Breeding station were studied for the presence of resistance genes markers to the following pathogens: Globodera rostochiensis, Globodera pallidа, Synchytrium endobioticum, potato virus X (PVХ) and potato virus Y (PVY). The method of multiplex PCR analysis was used. The varieties Shurminsky 2, Alisa, Viza, Chayka, Ognivo, Darik, Gloriya, Golubka, Virazh and a promising variety sample 56-09 were studied. In most (8 out of 10) genotypes, marker linked to the Sen1 gene of resistance to S. endobioticum was identified. DNA marker of the G. rostochiensis resistance gene (H1) and the G. pallida resistance gene marker (Gpa2) were found in six genotypes. The marker of the PVX resistance gene (Rx1) was detected in the varieties Shurminsky 2, Alisa, Chayka, Golubka, and Virazh. It has been established that none of the studied potato genotypes carries markers RYSC3, Ry186, YES3-3A linked to the PVY resistance genes. Although in the field, resistance was detected in the samples Chayka, Darik, Virazh, Alisa. Molecular markers linked to the largest number of resistance genes studied (H1, Gpa2, Sen1, and Rx1) were identified in the varieties Shurminsky 2, Golubka, and Virazh. Among the DNA markers used in the work, the data of potato genotype assessment using markers of virus resistance genes (PVX, RYSC3, Ry186, YES3-3A) were less consistent with field observations. The use of molecular markers makes it possible to determine the presence of resistance genes and assess the prospects of a sample in a short period of time, but, at the same time, requires careful choice of a DNA marker that is highly correlated with the manifestation of the trait.

The article presents the results of 2016-2020 study of the characteristics of growth and development of the pannonian clover variety Snezhok, bred at the Federal Agricultural Research Center of the North-East named N.V. Rudnitsky, while using the herbage for seeds. Uneven-aged herbage was assessed in the breeding nursery of 2016 sowing according to the characteristics of winter hardiness, the duration of individual interphase periods of development, plant height, structure of seed herbage, fruiting and seed yield. The overwintering of plants in all the years of research was high ‒ 100%. With an increase in the age of the stand, the prefloral (from growing to the beginning of flowering) and growing seasons from 47 to 72 and from 92 to 125-130 days (days) were lengthened. The height of plants in the phase of maturation of heads and seeds with the age of the stand also increased from 66.6 (1 year of use (y.u.)) to 97.1 cm (4 y.u.), the tendency of herbage to lodging increased from 0 (1 y.u.) to 30.9% (4 y.u.). In the first year of seed use (the 2 nd year of life (y.l.)), the minimum values of such structural indicators as the number of stems and heads per 1 m2 (245 and 151 pcs.), The content of generative stems in the total amount (42.8%), weight of seeds per 1 m2 (15.3 g). Starting from the 2 nd y.u. the listed structure indicators significantly increased and herbage stands were formed annually for three years, allowing them to be classified as highly productive: with the stem density of 366-405 pcs / m2 and a share of generative ones in them - 59.0-84.2 %, the number of heads - 350 -500 pcs / m2 , seed weight - 31.5-46.1 g / m2 . The level of seed productivity of pannonian clover depended to a greater extent on the age of the stand than on weather conditions during the period from regrowth to seed ripening. It was revealed that the biological (potential) seed yield in favorable years with sufficient technical support can reach 4.33 c/ha, while the actual (economic) average over the years of research was 0.54 c/ha, with changes from 0.20 (2017) up to 0.74 c/ha (2020).

The purpose of this research is to assess the level of thermal damage by determining the content of acid detergent insoluble crude protein (ADICP) in perennial cereal forage grasses Bromus inermis, Festuca pratensis, Phleum, depending on the phase of their vegetation (at the beginning of shooting, during the earing and flowering phases), as well as in silage and haylage prepared from them during the same phases. Samples for analyzes were dried at the temperature of 60-65 °C. Nitrogen of ADICP was determined in the residue of ADF (acid detergent fiber) obtained by filtering a solution of acid detergent through a paper filter. With the growth of grasses, an increase in the content of ADF in them was observed, followed by an increase in ADICP in Phleum and especially in Festuca pratensis which was characterized by higher rates of ADF accumulation. In Bromus inermis, the increase in ADF did not lead to an increase in the concentration of ADICP in the grass due to a decrease of its portion in ADF. The content of ADICP in green grass ranged from 0.85 to 1.58 % in dry matter, ADF ‒ from 27.0 to 45.8 %, no correlation was found between them. Conservation of grasses in all phases of their growth caused an increase in the content of ADF compared to the original grass, but the mass fraction of ADICP in the dry matter of silage and haylage was not higher than in the original grass, due to a lower mass fraction of ADICP in the ADF compared to grasses. In this regard, it is noted that if the technology of harvesting silage and haylage is observed, there is no increase in the level of thermal damage to these feeds. In this regard, it is noted, that when the preparation of silage and haylage is carried out according to the required technology, there is no increase in the level of thermal damage to these feeds. There is close correlation between the percentage of ADICP in CP (crude protein) and the contents of CP. The correlation coefficients were -0.83; -0.88 and -0.92 for grasses, silage and haylage, respectively. The lowest percentage of ADICP in CP was observed in the early phases of grass growth. In this regard, there is a need to harvest them in earlier growth phases, since the content of CP decreases with growth and the proportion of indigestible protein in it increases. If there are organoleptic signs of thermal damage to feeds given in the article, it is recommended to make an amendment to CP content on the basis of the result of the analysis for the content of ADICP.

The article presents the results of three-year (2017-2019) field studies on changes in agrochemical characteristics of soil and formation of productivity of birdsfoot trefoil and timothy grass mixture in dependence of the liming (hydrolytic acidity 0.25) and application of mineral fertilizers, phosphorite meal in particular. The soil is sod-podzolic, medium loamy, strongly acidic, with intermediate concentration of mobile phosphorous and metabolizable potassium, humus content is 1.9 %, and mobile aluminum – from 4.27 to 5.24 mg/kg of soil. It has been established that application of finely ground lime at a dose of 3 tons per hectare prior to sowing of birdsfoot trefoil and timothy grass mixture decreased soil acidity in the layer of 0-10 cm from 4.2 to 5.6 pH units by next autumn. Application of phosphorite meal (1t/ha) led to an increase in the concentration of mobile phosphorous in the layer of 0-10 cm by 135-163 %. The highest productivity of birdsfoot trefoil and timothy mixture during 3 years was obtained by means of combined application of lime and mineral fertilizers, and for 3 years on the average the yield of metabolic energy exceeded 50 GJ/ha, which is over 35 % higher than in the control variant without fertilizers. The use of mineral fertilizers increased grass mixture productivity only during the first two years. The applied dosage of phosphorite meal (1t/ha) promoted the increase in grass productivity on strongly acidic soil only in the year of sowing. Additional treatment with ammonium nitrate (N30) together with phosphorous and potassium fertilizers (Р60К60), as well as potassium chloride (К60) with phosphorite meal did not result in significant rise in metabolizable energy yield.

The studies were carried out in a field experiment in the north of the Arkhangelsk region. Under study were twocomponent grass stands of the first and second year of life, composed of cereal (meadow fescue, reed fescue) and legume grasses (meadow clover and blue alfalfa ). It has been established that in the climatic conditions of the Northern region the studied perennial grasses do not go through the full life cycle during the first year of life: meadow clover develops up to the root rosette phase, blue alfalfa – up to the branching phase, cereals ‒ to the tillering phase. In the first year, the yield is formed due to the legume component, especially meadow clover, which occupies 73 % of the structure. In the second year of life, cereal grasses increase their influence on the yield formation up to 93 %. The most productive variant in the second year was the “reed fescue + meadow clover” variant. With a higher ratio of the cereal component (67 %) in total for two mowings in comparison with the control variant "meadow fescue + meadow clover", the increase in dry matter yield was 2.81 t/ha (LSD05 = 1.46 t/ha), the output of exchange energy was 30.56 GJ/ha higher, crude protein yield increased by 0.22 t /ha. Agrophytocenoses of reed fescue and meadow clover in the first year of intensive use make it possible to obtain green fodder with the protein content in 1 kg of dry matter at the level of 114.28 g ‒ 153.33 g and sugars 133.54 g ‒ 154.65 g depending on the mowing. High loss of blue alfalfa in the grass stand is due to its weak winter hardiness and the effect of low spring temperatures during the period of the beginning of regrowth. Thus, in the conditions of the European North of Russia among legume-cereal grass stands during the first two years of life the grass mixture of meadow clover and reed fescue has been identified as perspective. There has been noted a potential for regulation the feed nutritional value (protein, sugars and fiber content) by means of grass mixture components selection.

The research was carried out in 1998-2018 in the conditions of the Komi Republic. Under study was the effectiveness of single application (1983) of lime doses (1.0; 2.0; 2.5 h. a.) and the systematic use of mineral fertilizers (N₆₀P₇₅K₇₅) against the background of lime effect in the cultivation of perennial grass mixtures (meadow clover, meadow timothy and cocksfoot). High efficiency was shown by liming at doses of 2.0 and 2.5 h. a., the effect remained for 35 years since their introduction to the soil. Thus, in 2018, the exchange acidity was 4.5-4.8 pHKCl (the initial 4.1-4.2 pHKCl). A similar decrease was observed in the hydrolytic acidity and the content of exchangeable aluminum in the soil. The amount of humus by 2018 increased to 1.7-1.8 % (the initial 1.4-1.5 %). The average yield of perennial grasses during soil liming at doses of 2.0 and 2.5 h .a. was 24.0-25.1 t/ha of green mass (5.3-5.5 t/ha of good quality dry matter), which is 52.8-59.8 % higher than the variant without fertilizers (15.7 green mass and 3.7 t/ha of dry matter). In the variant with the systematic use of NPK, the exchange acid content of the soil and the humus content remained at the initial level, the amount of the mobile forms of phosphorus and potassium increased to 198 and 121 mg/kg of soil (the initial 42 and 62 mg/kg). The average annual yield of grasses was 25.3 t/ha of green mass (5.4 t/ha dry matter) and was 61.1 and 45.9 % higher than the control. Against the background of the aftereffect of lime flour, the effect of NPK on soil properties was similar to the effect of non-fertilizing cultivation, with the exception of a significant increase in the availability of mobile forms of phosphorus and potassium – up to 254-288 and 148-166 mg/kg, respectively. A high yield of green mass of 28.1-30.7 t/ha (6.4-6.7 t/ha dry matter) was obtained, exceeding the control by 78.9-95.5 %. In these variants, grass mixture of high quality was obtained: the content of crude protein – 13.8-13.9 %; dry matter – 21.8-21.9 %; the content of total phosphorus – 0.92-0.94 %; potassium – 2.93-2.95 % and calcium – 0.79-0.81 %. The amount of nitrates in the feed did not exceed the MPC (147-149 mg/kg dry matter). Long-term studies on sod-podzolic poorly cultivated soil showed that the optimal method for the cultivation of long-term legume-cereal grass mixture was the use of lime flour (2.0 and 2.5 h .a.) and the annual use of N₆₀P₇₅K₇₅.

The field experiment on identifying differences in the effect of the herbicide and foliar feeding of plants with liquid nitrogen fertilizer (UAN-32) against the background of autumn tillage with a cultivator or plow on potato yield and phytopathologic characteristics of tubers during storage was carried out in 2019-2020 in the Nizhny Novgorod region. The experiment was laid on sod-podzolic sandy loamy soil in production conditions on two varieties of potato ‒ the super-early Сolomba variety and the medium-early Innovator variety grown for seeds. The variants under study were surface application of the soil herbicide Gezagard in a tank mixture with UAN-32 and foliar feeding of plants with UAN-32 (N₄₂) during the growing season against the background of N₄₂P₄₂K₁₆₉ (calcium chloride in autumn + ammonium nitrate phosphate in spring). The results indicate that the background fertilization provides the yield of Colombа variety potato of 20.7-29.0 t/ha, the Innovator variety – 17.4-23.1 t/ha. The use of the herbicide is more effective during autumn tillage with a cultivator, providing an increase in yield of 28-37 % on both potato varieties, feeding of plants with UAN-32 contributes to an increase in yield (8-10 %) only on the Сolomba variety. Plowing the soil for potatoes helps to avoid the pest damage of tubers and to reduce their susceptibility to rhizoctonia by 6-27 %, to wet rot ‒ up to 55 %. In general, it has been established that due to autumn plowing with fertilization at a dose of N₄₂P₄₂K₁₆₉, it is possible to obtain an increase in potato yield exceeding the increase provided both by herbicides and the use of foliar feeding of potatoes.

In the population of Kholmogor cattle (n=824), gametic disequilibrium was studied for alleles of the polymorphic loci β-Lg (LGB), β-Cn (CSN2) and æ-Cn (CSN3). In purebred Kholmogor cattle, the β-casein polymorphism is determined by three alleles with the frequencies of CSN2^А 1 – 0.368±0.0076, CSN2^А 2 – 0.497±0.0078, CSN2^B – 0.136±0.0056 and the frequencies of acasein of CSN3^А – 0.689 ±0.0061, CSN3B – 0.311±0.0061, respectively. The beta-lactoglobulin polymorphism is controlled by two alleles LGBA and LGB^B with a frequency of 0.237±0.0048 and 0.763±0.0048, respectively. In the population of breeding plants, the gametic disequilibrium was revealed according to the alleles of loci CSN2 and LGB; CSN2 and CSN3. The factor that caused the gametic disequilibrium was probably the initial difference between native Russian cattle and black-and-white cattle of Western Europe on the basis of which the Kholmogor breed gene pool was developed. The population showed an excess of haplotypes β-Cn^Вæ-Cn^В, β-Cn^Вβ-Lg^В (the "attraction" phase), apparently inherited mainly from native Russian cattle, and β-Cn^А 1æ-Cn^А, β-Cn^А 2β-Lg^А characteristic mainly for black-and-white cattle of Western Europe and a lack of β-Cn^Вæ-Cn^А, β-Cn^Вβ-Lg^А (the "repulsion" phase), probably due to the low frequency of these haplotypes in both initial breeds. The role of various factors in the occurrence and maintenance of gamete disequilibrium is discussed. It is suggested that for alleles of non-linked loci, longtime retention of gametic disequilibrium in population is most likely supported by selection

Milk productivity and a set of biochemical blood parameters characterizing the metabolic status were studied in suck-ling semi-fine-fleece wool-and-meat ewes of the first month of lactation (n = 80) of the experimental herd of L. A. Kaneva farm in the Ust-Tsilemsky district of Komi Republic. The ewes with lambs were kept in the same room in similar conditions of keeping and feeding. To characterize the metabolic type, all controlled ewes were divided into three groups depending on the level of their milk productivity. There was no significant linear variation of the metabolites during the transition from group to group. As a result of studying the associations between milking capacity and biochemical parameters of blood serum within the groups, in high-milking ewes of group 3, statistically significant correlations were found with the level of urea (r = -0.47, P < 0.05), and the activity of alkaline phosphatase (r = 0.40, P < 0.05), as well as not reliable, but relatively high coefficient with glucose (r = 0.36, P > 0.05). As a result of combining urea, alkaline phosphatase (AP) and glucose into one complex index – AP*glucose/urea, it was possible to increase significantly the correlation coefficient with milking capacity to 0.61 at P < 0.001. The obtained results indicate that high-milking ewes have metabolic features developed as the result of the body's adaptation to intensive lactation activity. These features are expressed in the interrelated fluctuation of three metabolites – urea, AP and glucose. It is assumed that urea indicates more efficient assimilation of nitrogen of the diet with an increase in milk productivity, intense inclusion of amino groups into metabolic processes necessary for the synthesis of milk proteins. Glucose and alkaline phosphatase indicate an increase in the intensity of cellular metabolism.

The paper presents an assessment of the effect of the Sedimine microelement product on the morphobiochemical composition of the blood of calves during the milk feeding period. For the experiment, 2 groups of heifers of HolsteinKholmogory breed at the age of 2-3 weeks were formed. The calves of the experimental group were injected intramuscularly with Sedimine at a dose of 5 ml three times with an interval of 7 days, and the control animals were given a saline solution in the same way. Blood for hematological and biochemical studies was obtained at the beginning of the experiment and a week after the first and last injection. According to the research it has been established, that after a single injection of Sedimine, there were no evident changes in the biochemical profile of the blood, with the exception of a decrease in the level of urea by 30.6% (from 4.9 to 3.4 mmol/l; P<0.001). After three-time administration of the drug, there was an increase in total protein by 9.6 % (from 54.2 to 59.4 g / l; P<0.05) and an increase in AlAT activity by 1.2 times (P<0.001), while in comparison with the control, the activity of AsAT was greater (P<0.01) by 43.4 % (57.5 U/l). The de Ritis coefficient in the experimental group decreased by 43.1 % (to 6.2; P<0.01), while in the control group, on the contrary, the indicator increased by 32.1 % (to 11.1). The ratio of calcium to phosphorus in all animals decreased by 28.8...32.1 % (P<0.001), but in young animals treated with Sedimine, the ratio was 16.7 % (0.84) higher compared to the intact group of calves (P<0.05). The concentration of thyroglobulin in the experimental group significantly decreased by 29.4 % (from 0.34 to 0.24; P<0.01), with stable values in calves that were treated with saline. Injections of the preparation contributed to the stable maintenance of iron in the blood of animals of the experimental group, the concentration of which was 3 times higher (P<0.01) in relation to the control, where the indicator was 5.9 micromol/l. Also, the control animals showed a decrease in the number of red blood cells by 31.9% (from 4.7 * 10 ¹² to 3.2*10 ¹²) and hemoglobin by 19.5% (from 87.2 to 70.2 g / l; P<0.05), with stable values in the experimental group, which were higher by 56.3 % (5.0*10¹²) and 22.2 % (90.2 g/l) compared to the control (P<0.05). Changes in white blood were characterized by a higher level of white blood cells in calves of the experimental group (by 27.7 %), primarily due to a 36.7 % (4.1*10⁹ ; Р<0.01) higher number of lymphocytic cells. Thus, a three-time injection of the test drug was quite effective in preventing iron deficiency in calves during milk feeding and had a positive effect on metabolic processes.

The purpose of the research was to study the effect of a phytocomplex containing herbal extracts of R. carthamoides, S. coronata, F. ulmaria on blood biochemistry of milking sows, the development and viability of piglets born by the time of weaning. For the experiment, the animals were divided into an experimental (Phytoadditive) and a control (SPK-2 compound feed) groups, 10 animals each. Phytoadditive in dry form was introduced into the diet of pigs of the experimental group during the sucking period (30 days) daily, once per head per day - 10 grams (individually). Before the beginning and at the end of the experiment, the blood of sows was examined for biochemical parameters. The multiplicity, the quality of the piglets born, the weight of the nest and one pig after birth and before weaning, as well as viability were determined. As the result, it was found that the concentration of the investigated extractives in the Phytoadditive was 13.5 g/kg, of which 10.5 g were ecdysteroids and 3.0 g of flavonoid rutin. Significant changes in the total protein content in the blood compared with the beginning of the experiment were noted in experimental pigs from 60.2±0.5 to 67.3±0.2 g/l (P <0.05) and in the control group from 61.0±0.2 to 66.1±0.1 g/l (P <0.05), the "Ca" content from 2.1±0.01 to 2.7±0.02 mmol/l (P <0.05) in the experimental group and from 2.0±0.01 to 2.5±0.02 mmol/l (P <0.05) in the control groups, while being within the normal range. The amount of albumin significantly increased only in the experimental group from 40.8±1.2 to 49.3±2.8 g/l (P <0.05), in the control from 42.2±2.1 to 46.0±1.5 g/l (P> 0.05). The number of piglets with low viability in the experimental group was 2 times less than in the control group. The viability of piglets in the experimental group by the time of weaning was 92.6 %, in the control ‒ 83.2 %.

Agricultural science in the Komi Republic dates back to 1911, when the Pechora Agricultural Experimental Station was opened on the initiative of the Northern researcher A.V. Zhuravsky. It was the first scientific institution of such specialization in the north of Russia above 65° north latitude. Zhuravsky identified the main tasks facing the agricultural science of the North: the development of agriculture (improvement of soil fertility, development of swamps for agricultural use), meadow and crop production, including vegetable growing, floriculture and fruit growing. He also defined the basis of agricultural production in the North – animal husbandry. While carrying out the studies, A.V. Zhuravsky Institute of AgroBiotechnologies solves all the problems raised. The modern structure of the Institute has three departments: the Department of Agriculture of the Far North, the Department "Pechora Experimental Station" and the Department of Agricultural Genomics organized on the basis of the youth laboratory in 2019. Over the past 20 years, the Institute has produced 12 varieties of perennial grasses, seven of which have been zoned. Among new breeding achievements are Pamyati Zhuravskogo Serpukh crowned (Serratula coronata L.) variety with an increased content of biologically active substances, potato varieties Zyryanets and Vychegodsky for food purpose, resistant to drought, cancer pathogen and golden nematode, highly resistant to late blight. Research on the technology of production of complex forms of nematocidal and insecticidal bio-preparations as a means of protecting agricultural crops from various soil-dwelling phytophages has begun. Thanks to the efforts of the Institute staff, in close cooperation with the farmers of the Arctic region of the Komi Republic, the Pechora sheep breed was preserved, and breeding work with rare native groups was widely developed. The Institute is the only agricultural research institution in the Komi Republic that provides scientific support for Nothern reindeer husbandry.