„ai“ 349 výsledků

Feed represents a substantial proportion of the variable costs of pig production. Feed efficiency is traditionally expressed as the feed conversion ratio (FCR) and more recently as residual feed intake (RFI). Although feed efficiency can be generally improved indirectly by selection for increased growth rate and decreased adipose tissue, a higher genetic response could be achieved through direct selection of feed intake traits. The aim of this study was to provide a pilot analysis of feed intake data of 281 Czech Large White boars. Data were recorded individually using the Feed Intake Recording Equipment in field performance testing from 2018 to 2020. The analysed feed intake traits were average daily feed intake (ADFI), FCR and RFI. RFI was calculated as the deviation of observed ADFI and average population ADFI predicted on the basis of the model, with mid-test metabolic weight and average daily gain as regressors. The heritability estimates were 0.35 and 0.34 for ADFI and FCR, respectively, and the estimate was slightly higher (0.43) for RFI. The genetic standard deviations ranged from 100 to 110 g of feed per day and 103 g of feed per kg of weight gain. The amounts of explained variability by environmental effects of jointly tested animals were from 0.20 to 0.46. The sufficient amount of genetic variability and moderate heritability estimates give the possibility for selection of feed intake traits, although a larger number of animals will be essential to estimate more precise breeding values.

Pregnancy assessment is a very important tool for the reproductive management in efficient and profitable dairy farms. Nowadays, mid-infrared (MIR) spectroscopy is the method of choice in the routine milk recording system for quality control and to determine standard milk components. Since it is well known that there are changes in milk yield and composition during pregnancy, the aim of this study was to develop a discriminant model to predict the pregnancy state from routinely recorded MIR spectral data. The data for this study was from the Austrian milk recording system. Test day records of Fleckvieh, Brown Swiss and Holstein Friesian cows between 3 and 305 days of lactation were included in the study. As predictor variables, the first derivative of 212 selected MIR spectral wavenumbers were used. The data set contained roughly 400,000 records from around 40,000 cows and was randomly split into calibration and validation set by farm. Prediction was done with Partial Least Square Discriminant Analysis. Indicators of model fit were sensitivity, specificity, balanced accuracy and Area Under Receiver Operating Characteristic Curve (AUC). In a first approach, one discriminant model for all cows across the whole lactation and gestation lengths was applied. The sensitivity and specificity of this model in validation were 0.856 and 0.836, respectively. Splitting up the results for different lactation stages showed that the model was not able to predict pregnant cases before the third month of lactation and vice versa not able to predict non-pregnancy after the third month of lactation. Consequently, in the second approach a prediction model for each different (expected) pregnancy stage and lactation stage was developed. Balanced accuracies ranged from 0.523 to 0.918. Whether prediction accuracies from this study are sufficient to provide farmers with an additional tool for fertility management, it needs to be explored in discussions with farmers and breeding organizations.

The study aimed at evaluating if the training of hens at their arrival in the production farm affected the distribution of animals in the aviary. Training consisted in raising by hand animals found on litter after turning off the light during the first two weeks. A total of 1,800 hens, aged 17 weeks, were allocated in 8 pens of the aviary and assigned to the trained or untrained groups. From 18 to 26 weeks of age, two operators recorded the number of animals on the different parts of the aviary at two observation hours (morning and afternoon). The training decreased the rate of hens on the floor (23.5% vs. 24.5%; P<0.05) and increased the rate of those on the third level (9.26% vs. 8.73%). The rate of animals on the floor (24.4% vs. 23.6%; P=0.05) and on the second tiers (36.9% vs. 33.2%; P<0.001) was significantly higher at morning hours compared to afternoon, whereas the rate of animals on the first tiers (29.6% to 33.7%; P<0.001) and on the perches of the third level (8.84% to 9.25%; P<0.05) was lower. As the age advanced, the rate of hens on the floor significantly increased (21% to 25% from week 18 to 26); animals at the first tiers decreased from week 18 (35.3%) to weeks 20-25 to reach the minimum value at week 26 (27.9%); differences in animals on the second tiers were erratic; rate of animals on the third level was the lowest (7.13%) at week 18 and the highest (11.7%) at week 26.

The objective of the present study was to investigate the effect of genotype and sex on growth and carcass traits of grazing lambs. A total of 32 lambs (16 Improved Jezersko-Solčava - JSR and 16 crossbreds with Texel - JSRT, 8 males and 8 females within each genotype) were included in the study. The lambs were grazed together with their dams from the beginning of the grazing period and had free access to commercial concentrate from the age of 10 days. Lambs were weaned at the average body weight of 22.9 kg. Feeding with a concentrate was finished when lambs achieved 35 kg of body weight and were slaughtered. Daily gains from birth to slaughter and from weaning to slaughter were calculated. Several carcass traits were determined. JSRT lambs had significantly higher daily gain from birth to slaughter, hot and cold carcass weights, and dressing percentages compared to JSR lambs. Carcass conformation was higher in JSRT than JSR carcasses. Also, carcasses of JSRT were shorter and wider than JSR carcasses. Rib eye muscle areas of JSRT lambs were significantly larger, and the colour was significantly lighter. Males had significantly higher average daily gain from birth to slaughter and from weaning to slaughter than females. Females had higher dressing percentages and subcutaneous and internal fatness scores than males. Females had significantly higher amount of kidney fat. The colour of males’ meat was significantly lighter than that of females. Crossbreeding with Texel rams improved growth and carcass traits of lambs, and males had better growth performance and several carcass traits than females.

A common practice to improve meat quality is aging under controlled conditions, which results in improved tenderness, a key factor in the consumer acceptance of beef meat. Among other traits, the tenderness and the effect of ageing are also genetically determined. Therefore, a trial was performed to assess the effect of ageing in the progeny of young bulls included in the routine breeding program for Simmental breed in Slovenia. In the trial, 127 young bulls were included, and the shear force of grilled Longissimus thoracis muscle was measured fresh and after three weeks of ageing. There was a significant difference between the fresh and aged muscle in shear force, but growth and other carcass traits did not affect it as it was expected. We assume that after enlarging the number of animals, the data will be usable to be included in the genetic evaluation of the breeding program for Simmental breed in Slovenia.

The present study aimed to evaluate the effects of optimum contribution selection (OCS) in a small native cattle breed. In practical animal breeding, the genetic improvement is often accompanied by an increase of inbreeding level due to the preferential use of closely related animals, particularly in small populations. This may lead to a reduction of genetic variability and to detrimental effects on some traits. The OCS maximizes the genetic merit of newborns while putting a restriction on the average relationship of the current generation. Despite the benefits, OCS has not been widely applied in practical breeding plans yet. This study considered the effects of OCS in the dual-purpose Rendena cattle, by applying different penalties to the average relationship of current generation (from 0 to -100,000). The OCS was applied on the candidate bull-dams and bull-sires for the years 2014 to 2019, and compared with simulations of random mating, traditional selection and mating system used by the breeders association. Considering the mating of 2014 and 2015, OCS allowed to obtain a predicted offspring with lower genetic merit than in traditional selection, but also with a lower inbreeding. When OCS was routinely introduced in the breed, in 2016, a reduction in genetic merit but also a consistent reduction in the average relatedness and inbreeding rate were observed. Subsequent years showed the actual effects of the OCS program: after the introduction of the optimization, the inbreeding rate did not increase over years. Moreover, the traditional mating system results were suboptimal in respect to OCS simulations. The study confirmed the benefit of OCS as effective tool for long-term preservation of small local breeds under selection, which is important for biodiversity and sustainable use of the genetic resources.

The increase of milk production at the farm level requires an accurate balancing of the diet and the nitrogen supply also to minimise the possible environmental pollution deriving from dairy farming. The aim of this study was to evaluate dietary protein utilization at different crude protein (CP) levels and to predict nitrogen content in faeces on the basis of nutritional parameters and milk urea nitrogen content (MUN, mg dL-1). The study was conducted on three groups (A, B, C) of lactating dairy cows (8 cows per group, including Latvian Brown and Holstein Black and White breeds) from 10 to 30 days in milk. Total mixed rations containing different levels of CP (approximately 18.0%, 17.5% and 17.0% for A, B and C, respectively) were fed. The amount of feed consumed by each cow was measured and feed samples collected during the trial. Milk yield (kg d-1-1) and faeces amount were recorded, and samples were collected at day 21 of the study for further analysis. Feed samples were analysed for CP, net energy for lactation (NEL, MJ kg-1) and other parameters. Milk samples were analysed for fat (%), total protein (%), casein (%) and urea content (mg dL-1). The statistical investigation was conducted using ANOVA, and correlation and regression analyses. The results showed that milk yield, fat, total protein, casein, urea, and MUN were not significantly different among groups being not affected by the dietary CP levels. The correlation between faecal nitrogen content and CP content in feed was moderately positive and statistically significant (r=0.44, P=0.03), while the correlation between faecal nitrogen content and MUN was moderately negative and showed tendency towards significance (r=-0.39, P=0.06). The regression analysis showed that feed CP explained approximately 20% of faeces nitrogen content.

The objectives of this study were to investigate non-genetic sources of variation of fertility in Reggiana cattle and identify the best model for future genetic analysis. Moreover, the variation of target fertility traits in the different parities and months of first service was evaluated. The investigated fertility traits were interval between calving and first insemination, interval between calving and conception, number of inseminations per conception, and calving interval. The dataset included 22,731 records of 10,502 cows, collected between 1986 and 2019. Four different models were tested: Model 1 included the fixed effects of herd-year-month of first service and parity; Model 2 separately accounted for herd-year and month of first service, in addition to parity; Model 1a and Model 2a were Model 1 and Model 2 with the addition of the effect of age at first insemination. Model 1 had an average coefficient of determination of 0.40 for the traits, and this value increased to 0.48 in Model 1a. Moving to Models 2 and 2a, the coefficient of determination dropped to average values of 0.21 and 0.27, respectively. Regarding the effect of month of first service, the best fertility performances were observed in March and April, whereas for parity effect the best performance was in third lactation. Model 1a presented the best R2 for all studied traits but data editing for age at first insemination was too strict. On the other hand, in Models 2 and 2a variance absorbed by fixed effects was low, and this resulted in potentially biased estimates. Model 1 was therefore the best trade off between data loss and predictivity.

In this study, 68 genotyped purebred cows and bulls of Charolais cattle were used to determine runs of homozygosity (ROH) for evaluation of selection effect on the genome structure. ROH analysis was performed for 41,153 SNPs, and homozygous segments considering a minimum of 15 consecutive SNPs. The aim was to identify if regions of the genome with a high frequency of SNPs in ROH include signatures of selection. The most significant outlier SNPs were found on BTA2, 5, 7 and 19 (11 regions), with a sum of ROH length of 15.85 Mb. These regions contained genes included in various biological processes associated with the functioning of the immune system, growth, reproduction and metabolism. Various quantitative traits loci (QTLs) which affected the characteristics of meat production and reproduction have been identified in these regions. Overall, obtained results suggest that the Charolais cattle genome includes selection signatures reflecting the improvement of meat production and reproduction in accordance to breeding objecives.

Arbuscular mycorrhizal fungi (AMF) play an important role in nutrition of most plants as well improving soil fertility. The present study investigated the effects of different AMF isolates (Funneliformis mosseae, Rhizophagus intraradices and Claroideoglomus etunicatum) and control on soil chemical properties, growth and nitrogen (N2 ) fixation in two soybean cultivars (TGx 1448-2E and TGx 1440-1E) in phosphorus (P)-deficient soil. The study was laid in split plot in a randomized complete block design with three replications. The results showed increased root colonization (up to 76%) with AMF inoculation compared to uninoculated control. The inoculation of the AMF isolates enhanced the growth parameters, nodulation and dry weights, which resulted in increased number of pods, 100-seed weight and seed yield. More pronounced effects were observed with F. mosseae and R. intraradices inoculation compared to C. etunicatum. In addition, similar trend was observed for P and N content in the plants as well the N2 fixation activities, which resulted in increased total N fixed in both cultivars (up to 27.9 and 27.4 kg ha-1 respectively). After harvest, the results showed improved soil fertility in terms of soil N, available P, soil pH, organic carbon as well as exchangeable cations (calcium, magnesium, potassium and sodium) with AMF inoculation. TGx 1448-2E inoculated with F. mosseae gave the highest seed yield (1,773 kg ha-1). The findings from this study suggest that R. intraradices or F. mosseae could be used to enhance N2 -fixation, soil fertility and productivity of soybean in phosphorus-deficient soils.

The present study deals with examining the response of maize to osmotic stress condition. In the experiment, two investigated plants which are maize were chosen to be tested in the controllable environment. One plant was controlled to be in well water condition, whereas another one was treated by PEG-6000 for being encountered the osmotic stress condition throughout the experimental period. The main measuring technique used to monitor the tested plants in the experiment consisted of acoustic emission techniques. The experimental results indicated that the distinct reactions between a control plant and an influenced plant according to osmotic stress condition could be differentiated by acoustic emission method.

The aim of the study is to screen the bioactive compounds (saponin, tannin, phenolic compounds, terpenoid & steroid) present in selected ethnomedicinal plants, Terminalia bellirica (fruits), Smilax zeylanica (leaves) and Dioscorea oppositifolia (fruits) from Odisha state, India. The single formulation was prepared using the selected plants parts in the ratio 1 : 6 : 3 respectively for quantitative analysis of tannin & total phenol, antioxidant activity and analysis of MIC (Minimum Inhibitory Concentration) against Streptococcus mutans causing bacteria of tooth decay. Results revealed that selected plant parts are rich source of bioactive compounds like tannin, phenolic compounds and saponin. The quantitative analysis of secondary metabolites showed highest concentration of tannin. It was noted that antioxidant activity is highest in methanol extract as compared to aqueous and acetone. MIC analysis also revealed that formulated powder had excellent antibacterial activity against S. mutans and it was observed the lowest values (450 µg ml-1) showed aqueous & methanol followed by acetone. The herbal formulation might be used to formulate new herbal products against tooth decay in near future.

The breeding studies targeted to develop high yielding varieties in maize have led to a decrease in genetic variation in secondary biochemical components. Local maize landraces are important genetic sources for these components. The objective of this study was to examine the genetic variation for phytic acid and total phenolic compounds within 192 Turkish maize landraces. The plant material was grown during the summer season of 2017 in Çanakkale, with the inclusion of 7 check hybrids. The field trial used an Augmented Experimental Design, with 6 blocks, each one containing 32 landraces and 7 check hybrids. Phytic acid and total phenolics were detected spectrophotometrically in the seeds of landraces propagated by bulk pollination. The data were subjected to analysis of variance and some genetic estimations (coefficients of variation, heritability, genetic advance) were calculated for the observed traits. Results of data analysis suggest that there is a considerable genetic variation among the investigated genetic materials. The phytic acid content was found between 0.82–4.87 mg g-1 and the total phenolic content was between 0.03–1.99%. For both traits, genetic variation in local maize landraces was observed to be wider than check varieties. The promising materials among landraces may have potential use in the future breeding programs for manipulating the levels of phytic acid and phenolic compounds. According to the calculations made for the inheritance of the traits, it was determined that the heritability in phytic acid content was higher (56.2%) than those for the total phenolics. Genetic gain calculations showed that genetic improvement can be achieved by selection for both investigated traits.

Our research aimed to analyse the current state of the sheep industry in Ukraine, to highlight the geographical location of genetic resources, to describe the state of the breeding work, and to form the proposals for the development of this branch in the future. The date from the State register of breeding farms for 2005-2019 and statistical reporting were used for analysis. It is shown that over the last 14 years, the sheep industry in Ukraine has undergone significant changes: the form of ownership has changed, the number of livestock has decreased and the breed composition of sheep has changed. Currently, there are 0.7 million sheep in Ukraine, of which 26.7 thousand are registered like breeding animals belonging to 10 breeds. The largest number of sheep is concentrated in the south and west of the country, where the climatic conditions are favourable for this branch in the past. The leaders in terms of numbers are Odesa and Transcarpathia, Chernivtsi and Zaporizhia regions. Breeding pedigree animals are concentrated in Odesa and Kherson oblasts. The most numerous breeds are the Askanian meat-wool breed with crossbred wool and the Askanian Karakul breed. Taking into consideration the big potential of the sheep breeding, it is proposed to perform some steps to stimulate its development in Ukraine.

Post-harvest losses of agricultural produce due to storage food grain pests lead to detrimental effects on the economic growth of any nation. However, a solution to this is to rely on adapting necessary cultural operations and effective traditional remedies that are locally available, which are inexpensive for the control of pests. Tithonia diversifolia (Hemsl.) A. Gray is an invasive weed that grows along the roadside and wasteland in rural and urban areas. The objective of this study was to evaluate the pesticidal efficacy of powder and extracts of T. diversifolia flower by using different solvents such as aqueous, methanol, chloroform, hexane, petroleum ether and ethyl acetate against rice moth, Corcyra cephalonica. The dry powder and extracts of T. diversifolia flower were tested to check the mortality of C. cephalonica eggs, larvae, and adults under the laboratory conditions (28 ±2 °C and relative humidity 65 ±5%). The mortality of the insect increased with an increase in the concentration of extracts. The results showed that the different solvent extracts of T. diversifolia flower were significantly more effective than the dry powder and control against different developmental stages of C. cephalonica. Methanol and ethyl acetate extracts showed an almost equitoxic lethal effect on all three stages of the life cycle of C. cephalonica. The present work suggests that the T. diversifolia flower possesses insecticidal properties against C. cephalonica eggs, larvae and adults. Thus, it can be recommended for use by the farmers as a potential pesticidal plant.

The study was undertaken at Regional Agricultural Research Station of Bangladesh Agricultural Research Institute, Ishurdi, Pabna, Bangladesh in consecutive two years of 2015 and 2016 for evaluating the performance of maize and Indian spinach intercropping (MIS) under different row spacing for higher profitability through economic assessment. Five different cropping systems viz., T1 : hybrid maize normal row along with one row of spinach, T2 : hybrid maize paired row along with one row of spinach, T3 : hybrid maize paired row along with two rows of spinach, T4 : hybrid maize paired row along with three rows of spinach and T5 : sole maize were included in this experiment. The performance of the component crops was evaluated regarding total grain and vegetable yield, competitive functions, and economic returns. The results indicate that yield and yield contributing characters of maize were not significantly affected by the intercrop of spinach at different ratios. Maize paired row along with three rows of spinach (IS) (T4 ) combination had higher maize equivalent yield (11.06 t ha-1), gross return (US$ 1,499 ha-1), gross margin (US$ 564 ha-1) and benefitcost ratio (BCR) (2.07) than others treatments. This intercropping system also recorded higher land equivalent ratio, monetary advantage index, land equivalent coefficient, income equivalent ratio and area time equivalent ratio of 1.24, US$ 2,434 ha-1, 0.30, 1.24 and 1.18, respectively. Hence, this cropping system may adopt in the smallholders’ for getting maximum benefits in prevailing climate change.

Multi-environment trials were conducted in two locations (Algiers and Setif) during two crop seasons in order to assess the responses of 17 genotype of barley (Hordeum vulgare L.) by evaluation of genotype-by-environment interactions (GEI) on grain yield and determine the stable genotypes. Results showed significant (p <0.001) effects of environment and genotypes and their interaction on grain yield. The genotypes had different behavior conducting to yield variation in the tested locations. So, selection could consider a specific adaptation of the genotypes and their yield stability. The Additive main effects and multiplicative interaction analysis is a useful tool allowing to explore important information on the obtained results; it revealed that ‘Plaisant/ charan01’ is the most stable genotype followed by ‘Barberousse’ and ‘Barberousse/Chorokhod’, while ‘Begonia’ and ‘Plaisant’ were unstable with specific adaptation to Setif location during 2018/19. the cultivar ‘Express’ presented a high productivity.

Genetically modified (GM) maize and traditional maize were tested experimentally to determine their effect on chicken serum biochemical parameters and metabolism. A total of 600 day-old chicks were divided into 2 experimental groups, namely: K, diet based on traditional maize (control); D, a diet based on GM maize (experiment). The experiment lasted 17 weeks, daily monitoring of population viability and feed consumption were carried out, at the age of 4, 8 and 17 weeks all birds were individually weighed. Blood samples for biochemical studies were taken from chickens at 4 weeks and 12 weeks of age (n= 6). Analytical studies did not show significant changes in serum biochemical parameters in group D chickens. A significant difference between the groups of chickens receiving GM and traditional maize was found only by the content of lipids after 4 weeks (P < 0.05) and cholesterol after 12 weeks of the experiment (P < 0.001). Also noted increasing level of CIC in serum of chickens that consumed feed from GM maize relative control at 32.2% (P < 0.01) after 4 weeks of the experiment. However, the studied indicators of metabolism and immune response in birds were within the physiological range. Certain fluctuations in the parameters during the experiment were observed in both groups, which indicates that there is no connection between this fact and the feeding factor. In addition, optimal results were obtained in terms of feed conversion and body weight of poultry, regardless of the feeding ration. The body weight of chickens at the age of 17 weeks in both groups was in the range of 1862.4-1895.6 g, feed consumption per 1 kg of body weight gain was 3.65-3.76 kg, the livestock viability – 96.6-97.3%. The results of the study do not indicate any danger to the metabolism and health of the bird due to the use of genetically modified feed, as no statistically significant differences within the studied parameters were observed. The noted certain small deviations fell within the limits of normal variations of the considered indicators and, thus, had no biological or toxicological value.

DGAT1 gene polymorphism in exon 8 AA→GC which converts lysine to alanine at position 232 (K232A) was determined to have significant influence on bovine milk production characteristics like milk yield, protein content, fat content, and fatty acid composition. The aim of this study was to analyse the effect of DGAT1 gene polymorphism on dairy production traits [milk yield (kg), fat yield (kg), fat content (%), protein yield (kg) and protein content (%)]. Genotyping of 136 Holstein cows was performed using the ACRS-PCR method. The genotypes frequencies were as follows: homozygous genotype AA (80.88%), heterozygous genotype AK (16.91%) and homozygous genotype KK (2.21%). In the monitored population, allele A had a predominance with a frequency of 89.34% over allele K with a frequency of 10.66%. In the study was observed a statistically significant (P <0.0001) effect of DGAT1 K232A marker genotypes on breeding value variability for milk fat and protein content (%) as well as milk yield (kg) was observed.

The effect of use of complete feed with different protein levels on the morphological composition of the body and the amino acid content of trout meat proteins is studied in the article. For this purpose, five experimental groups were formed by the analog method. The study lasted 210 days and was divided into two periods: equalizing (10 days) and basic (200 days). In the equalizing period, the trial fish consumed feed of the control group. In the basic period, the level of protein in the feed of trout of the experimental groups was regulated by changing individual components of the feed. Feeding of rainbow trout in the study period was performed 4-6 times a day, in the day time at regular intervals. The required amount of feed was calculated according to the indicators of individual fish weight and ambient temperature at the time of feeding. Rearing of commercial two-year-old ones was performed in ponds with an area of 100 m2 at a fish-holding density of 50 specimens/m2 and a water level of 1 m. The total number of trout in experimental studies was 25 thousand specimens. The use of feed with high crude protein content in the period of commercial rainbow trout rearing improves their commercial properties, while fish feeding with feed with crude protein content at the level of 44% leads to a decrease in their productivity.