Lower Feed Consumption Research Articles

Distinct and Quantitative Validation Method for Predictive Process Modelling in Preparative Chromatography of Synthetic and Bio-Based Feed Mixtures Following a Quality-by-Design (QbD) Approach

Process development, especially in regulated industries, where quality-by-design approaches have become a prerequisite, is cost intensive and time consuming. A main factor is the large number of experiments needed. Process modelling can reduce this number significantly by replacing experiments with simulations. However, this requires a validated model. In this paper, a process and model development workflow is presented, which focuses on implementing, parameterizing, and validating the model in four steps. The presented methods are laid out to gain, create, or generate the maximum information and process knowledge needed for successful process development. This includes design of experiments and statistical evaluations showing process robustness, sensitivity of target values to process parameters, and correlations between process and target values. Two case studies are presented. An ion exchange capture step for monoclonal antibodies focusing on high accuracy and low feed consumption; and one case study for small molecules focusing on rapid process development, emphasizing speed of parameter determination.

Determination of mechanisms of action of active carbons as a feed additive

Activated carbon’s porous structure allows it to adsorb a substrates, products and catalysts from the environment thus modificated the biocatalysis processes in digestive tract. Active carbons are currently used to remove solvents from gas streams and for water purification; however, few studies have examined the mechanisms of action of active carbon during the biotransformation processes in the digestive tracks. The potential benefits of using activated carbon in feed are uncertain because both its chemical and physical properties can vary significantly depending on the type of carbonaceous feedstock. However, the use of active carbons as dietary supplements can also bring many benefits during biotransformation processes in the gastrointestinal tract. Active carbons can adsorb toxins from the gastrointestinal tract and reduce excessive intestinal gas accumulation. The study concerning the adsorption of bacteria and vitamins on the porous structure of various species of active carbons is an important factor to determine their mechanism of action in biocatalysis in digestive system. The use of properly modified activated carbons as feed additives may have a beneficial effect on the development and functioning of breeding animals in the future.The results of our research show that the active carbon obtained from beech (KB), which contained, on average, 14% oxygen content by weight adsorbed bacteria, such as E. coli and S. aureus, better than all the other active carbons tested. Moreover, the meso- and macropores of carbon seem to contribute little to bacterial adsorption by active carbons. The electron microscopy studies confirmed that the bacteria adhered mainly to the active carbon surface. Our results also indicate that the examined active carbons from beech (KB), coconut shells (TE50), and hard coal (RB2) do not adsorb (or adsorb with very limited efficiency) the vitamins that are routinely added to feed, such as A, B1, D, and K. Broilers fed with feed mixtures supplemented with activated carbon (KB) resulted in increases in the weight of the chickens (∼2%) after 14 days of application and 2% lower feed consumption (conversion) relative to a control sample. Our data indicate that modifying the surface area and elementary content of active carbon may affect its specificity and selectivity and its capacity to absorb particles used in veterinary, human pharmacy, and cosmetology.

Producción de tilapia (Oreochromis niloticus L.) en la etapa de engorde con dos estrategias de alimentación

La tilapia gris (Oreochromis niloticus L.) es una excelente opción para la producción acuícola debido a su resistencia a condiciones adversas, enfermedades y sus hábitos alimenticios. Se evaluaron dos estrategias de alimentación durante la etapa de engorde, la cual finaliza al alcanzar un peso ideal de 1,085 g a la cosecha. Las estrategias de alimentación fueron ad libitum y alimentación al 90 % del ad libitum. El ensayo se realizó en AquaFinca Saint Peter Fish, Cortés, Honduras. Las variables medidas fueron: índice de conversión alimenticia (ICA), índice de alimentación (IA), días a cosecha (Decos) y ganancia de peso diario (GDP). Las unidades experimentales fueron doce jaulas flotantes, seis jaulas ad libitum y seis jaulas con el 90 % del ad libitum; cada jaula tenía un volumen de 1,380 m3 con una capacidad de 50,000 peces. El análisis estadístico se realizó por medio de una prueba t (P ≤0.05). La alimentación ad libitum y al 90 % del ad libitum no presentaron diferencias en ICA (1.88 y 1.82 respectivamente), tampoco se presentaron diferencias en GDP con 6.39 g ad libitum y 6.16 g con 90 % del ad libitum. El tratamiento ad libitum presentó un IA de 3.19 y el 90 % del ad libitum de 3.06; Decos fueron 157 y 165 respectivamente. El tratamiento al 90 % del ad libitum, además de representar un ahorro en alimento no tuvo efecto sobre el ICA, pero si se retrasó ocho días para llegar al peso ideal de cosecha con una diferencia de 26,270 kg de alimento entre ambos tratamientos.

Growth performance of local and genetically improved chicken of Bangladesh

The experiment was conducted to compare the growth performance among four genotypes of indigenous chicken namely Non-descriptive Native (ND), genetically Improved Native (IN), Hilly (HC) and Naked Neck (NN) of Bangladesh under free-range rearing system. A total of 288 day old chicks (DOC) from four genotypes were divided into four treatments having eight replications of each for a period of 12 weeks under free-range system with supplementation of commercial broiler diet. During first 4 weeks, all chicks were kept together, whereas chicks of ND was brooded in the same room but separated by a partition. At 5 weeks of age chicks were randomly distributed to the selected farmers. Growth parameters were recorded to determine the comparative growth performance among four genotypes of chicken. The highest body weight (1110.76 g/bird) was achieved by HC, followed by IN (900.63 g/bird) and NN (831.13 g/bird) at 12 weeks of age. The lowest body weight (734.13 g/bird) however was found in ND chicken. During the growing period under free range rearing (5-12 weeks), HC group consumed the highest amount of feed (2697.02 g/bird) with an average FCR of 3.06 while the lowest feed consumption (2666.13 g/bird) with the highest FCR of 4.90 was observed in ND. IN consumed (2674.63 g/bird) feed with an average FCR of 3.92 and BLRI improved NN consumed (2668.13 g/bird) feed with an average FCR of 4.19. Live weight gains in all the four genotypes of indigenous chicken were changed almost in a similar pattern. Significant differences were observed in live weight, dressing percentage, breast meat, drumstick, thigh meat among the four genotypes of chicken. The HC was superior to other genotypes of indigenous chicken including ND in terms of growth performance, meat yield characteristics and net returns.
 Bang. J. Anim. Sci. 2018. 47 (2):76-84

Evaluation of the Impact of Light Source on Reproductive Parameters in Laying Hens Housed in Individual Cages.

Higher light wavelengths have been shown to stimulate extra-retinal photoreceptors more efficiently than lower wavelengths to promote reproduction in poultry. We developed a light emitting diode (LED) bulb that emits 60% of its light in the red spectrum (LED-R), and evaluated the effects of different light sources on growth and reproduction in commercial layer hens. Three rooms equipped with either 100W incandescent, 15W compact fluorescent (CFL), or 10W LED-R bulbs were populated with 96 Lohmann LSL-Lite layers housed in individual cages from 14 to 69 weeks of age (woa). Pullets were initially maintained on a 10-h photoperiod, then photostimulated at 18 woa. Surprisingly, regardless of the light source, plasma levels of estradiol peaked at 16 woa, 2 weeks before photostimulation, and egg-laying was initiated at 19 woa. As a direct correlation between age at first egg and body weight was identified, metabolic cues most likely served as a primary trigger to initiate sexual maturation prior to photostimulation. Overall egg production and cumulative egg numbers were similar among treatments. Interestingly, a second increase in estradiol was observed at 52 woa under all treatments, suggesting an additional ovarian stimulation, possibly associated with an additional follicular recruitment at that age. Overall, changes in estradiol concentrations were more pronounced in hens maintained under LED-R light than in hens exposed to incandescent and CFL, especially for the second increase, suggesting that a higher amount of red light leads to stronger ovarian activity. Maintaining hens under LED-R bulbs also resulted in lower feed consumption, which combined with the lower energy consumption of LED-bulbs (LED-R: 306 kW; incandescent: 2,514 kW; CFL: 422 kW) could reduce the production cost.

Effect of the combined action of Quercus cortex extract and probiotic substances on the immunity and productivity of broiler chickens.

Aim:This study was designed to investigate the synergistic effect of the combined action of probiotic bacterial strains (Bifidobacterium adolescentis and Lactobacillus acidophilus) and Quercus cortex extract as biologically active substances in the feed on the immunity and productivity of Gallus gallus domesticus.Materials and Methods:For the experiment, 120 7-day-old broiler chickens were selected (4 groups, n=30, 3 replicates with 10 birds in each group). The groups were as follows: The reference group - basic diet (BD); experimental Group I - BD + Q. cortex extract (Q. cortex), 2.5 ml/kg of body weight; experimental Group II - BD + probiotic preparation based on B. adolescentis, 80.0 million colony-forming units (CFU), and L. acidophilus, 1.0 million CFU (dosage in accordance with the recommendations of the manufacturer); and experimental Group III - BD + probiotic + extract of Q. cortex. The following methods of study were used: Chemiluminescence and biochemical and hematological analysis.Results:The results of the experiment showed a slight decrease in the level of leukocytes in Groups II (p≤0.05) and III, and of hemoglobin in Group III (p≤0.05), compared to the reference group. The level of alanine aminotransferase and aspartate aminotransferase in Group II was higher than both the reference group (p≤0.05) and the other groups. Introduction of Q. cortex extract into the diet increased the level of triglycerides (p≤0.05) and urea in the blood serum. The combined use of probiotic preparations and the extract resulted in an increase in the level of iron in the blood serum by 78.1% (p≤0.05) in Group III. An increase in indicators of the antioxidant system (catalase increased in Group I by 27.2% (p≤0.05) and by 3.0–12.7% in other groups; superoxide dismutase increased by 3.0–13.2%) and nonspecific immunity (β-lysine increased by 8.8–16.0%) was noted. Introduction of the extract and probiotic preparation into the diet contributed to increasing the live weight of chickens at the age of 15 days by 5.9 and 7.4%, respectively (p≤0.05). In experimental Group II, this trend continued, and by the end of the period, the weight of animals exceeded that of their peers in other groups by 0.7-7.0%. Given the high preservation rate of poultry in the II and III Groups, and the low feed consumption per 1 kg of live weight gain (by 3.1–6.7%), the efficiency of growth was higher than in the reference group.Conclusion:Thus, the combined use of probiotic strains of bacteria and Q. cortex extract helped to increase the antioxidant activity of the organism and antimicrobial components of blood plasma compared with broiler chickens with similar growth rates but without the supplementation of this combination.

Effect of Supplementation of Amla (Emblica officinalis) Fruit Powder on Growth Performance during Different Growth Phases of Broiler Chicken

The aim of the study was to assess the efficacy of phytogenic feed additives as an alternative to antibiotic on growth performance of broiler chicken. A total of 300 commercial broiler chicks were randomly distributed into six treatments having five replicates consisting of ten birds each. The chicks fed with standard basal diet in two different growth phase i.e. starter(0-28d) and finisher (29–42 d) The first group was kept as control (T1) and given basal diet without antibiotic while in second group (T2) basal diet was supplemented with antibiotic, third (T3), fourth (T4), fifth (T5) and sixth (T6) groups were supplemented with amla fruit powder @0.25%, 0.50%, 0.75% and 1%, respectively. Over all feed intake ranged 3860.4 (g) (T6) to 4059.0 (g) (T1) and significantly lower feed intake was found in 0.75% and 1% amla fruit powder supplemented group as compared to control. The lower feed consumption in higher levels of amla fruit powder supplemented group might be due to better utilization of nutrients. Over all weight gain at the end of growth period ranged 2105.8 (T1) to 2240.4 (T5) and significant higher body weight gain was found in 0.75% (T5) and 1% (T6) amla supplemented group results in significantly improved FCR as compared to control. Dry Matter metabolizability and Nitrogen metabolizability was significantly higher in 0.75% (T5) and 1% (T6) amla fruit powder supplemented group as compared to control group. Higher gross energy metabolizability was recorded in all amla supplemented and antibiotic supplemented group as compared to control group.

EFFECT OF USING DIFFERENT LEVELS OF MORINGA OLEIFERA MEAL IN THE DIETS OF JAPANESE QUAILS ON THEIR PRODUCTIVE PERFORMANCE

The aim of this study was to inspect the effect of feeding Japanese quail chicks on diets containing different levels of Moringa Oleifera meal (MOM) on productive performance, carcass quality and blood constituents. Six hundred unsexed one- week-old birds of Japanese quail were equally divided into five experimental groups of 120 birds each. They were fed at 0, 5, 10, 15 and 20% with MOM. The experiment lasted for six weeks during which the effect of MOM on the body weight, feed consumption, feed conversion, blood constituents and carcass traits were observed as indicator of performance. The results showed that, birds fed on 5 % MOM gained significantly higher body weight and body weight gain than birds fed the control diet, but the lowest feed consumption (P≤0.01) and best feed conversion ratio were obtained by using 20% MOM compared to control group. Using 20% MOM increased the weight of heart and liver significantly (P≤0.05) than other groups, but there were no significantly (P>0.05) differences in gizzard, carcass and edible parts weights of the growing Japanese quails in the four treatments. Plasma total protein and albumin were significantly higher in two groups (15 and 20 %) MOM as compared to other treated groups or control group. The best level of MOM was 20% which recorded a decrease in plasma cholesterol and LDL compared to control group, but plasma AST and ALT decreased with all levels of MOM. This study indicate that the 20% MOM diet can improve quail performance without negative effects on growth and carcass traits.

Effects of a meal feeding regimen and the availability of fresh alfalfa on growth performance and meat and bone quality of broiler genotypes

ABSTRACT1. The aim of this study was to identify a feeding regimen that encourages good pasture use in slow (SG) and fast (FG) growing broiler genotypes under free-range management.2. SG and FG birds fed on either an ad libitum (ADB) or a meal feeding (MEF) programme were given free outdoor access with or without fresh alfalfa from day 22 to 72 and from day 22 to 45, respectively. In two consecutive trials, 800 birds of each genotype were included in a factorial design using groups of 40 birds replicated 5 times.3. Fresh alfalfa consumption did not improve growth performance and meat quality attributes, whereas the feeding regimen had significant implications. When compared with their ad libitum-fed counterparts, meal-fed birds showed a significantly lower body weight at a considerably lower feed consumption rate, leading to a more favourable feed conversion ratio (FCR) during the course of the experiment.4. The MEF regimen with a strong feed limitation significantly increased crop and gizzard weight in both genotypes. In FG birds, water holding capacity, drip loss, cooking loss and pH 45 in the breast and thigh meat were adversely affected by MEF; however, feed restriction demonstrated benefits with significant decreases in muscle fat accumulation. In SG birds, decreases in protein and dry matter content of the breast and thigh muscle with meal feeding were conclusive.5. In both genotypes, there was no treatment-related effect on meat yield, mineral composition of the meat or bone mechanical properties.6. In conclusion, MEF, irrespective of alfalfa intake, may provide a viable method to decrease FCR; it may be able to contribute to the production of chickens with lean carcasses but it was not capable of improving overall meat quality.

Feed efficiency of diets with different energy and protein concentrations supplemented with methionine in laying quails

The study was conducted to evaluate the feed efficiency of quail diets containing different concentrations of metabolizable energy (ME) and crude protein (CP) with constant ratio and supplemented with methionine. Four hundred laying quails (Coturnix coturnix japonica) were randomly assigned to four experimental diets in a 2×2 factorial arrangement. Each dietary treatment used 5 replicates of 20 quails. Two basal diets were formulated to contain 2,800 kcal kg-1 ME and 18.7% CP (High ME-CP) and 2,600 kcal kg-1 ME and 17.3% CP (Low ME-CP). Each basal diet was supplemented with 0 and 0.12% methionine. The High ME-CP diets generated lower feed consumption but higher egg mass and feed efficiency (P<0.01) compared with the Low ME-CP. Furthermore, supplementation of methionine increased egg mass, feed efficiency, energy efficiency ratio and protein efficiency ratio (P<0.01). The High ME-CP supplemented with methionine resulted the highest feed efficiency followed by the Low ME-CP supplemented with methionine, while both High ME-CP and Low ME-CP without methionine supplementation resulted the lowest feed efficiency (P<0.05). In addition, ME and CP consumption of the birds were not influenced by the treatments. Thus, feeding High ME-CP supplemented with 0.12% methionine provided benefit to improve the feed efficiency in laying quails.

Dietary zinc supplementation and the performance and behaviour of caged laying hens

There is considerable behavioural evidence demonstrating stress reactions in birds. Behaviour of birds can affect their performance parameters. Also, nutritional factors may affect the behaviour of laying hens. Dietary deficiencies, such as minerals can increase feather-pecking behaviour and cannibalism. In the present study, we evaluate the effect of dietary zinc (Zn) on performance and behaviour of laying hens with four treatments (40, 70, 100, 130 mg Zn/kg of diet) with 96 Hy-Line W-36 leghorn hens for 10 weeks. The results showed that egg production for hens receiving 130 mg Zn/kg of diet was significantly higher than for those receiving 40 and 70 mg Zn/kg of diet (P &amp;lt; 0.05). Those hens receiving 130 mg Zn/kg of diet had lower feed consumption compared with those that had other treatments (P &amp;lt; 0.05). Dietary inclusion of Zn caused an improvement to feed conversion ratio (P &amp;lt; 0.05). There was a treatment × time interaction on feeding behaviour that hens received 130 mg Zn/kg of diet spent significantly less time at the feeder than the other treatments. Hens receiving 130 mg Zn/kg of diet spent significantly less time drinking than the hens that received 40 and 70 mg Zn/kg of diet. Also, those that received 130 mg Zn/kg of diet did more non-nutritive pecking and preening than the hens that received 40 and 70 mg Zn/kg of diet. High levels of Zn decreased the aggressive behaviour of hens compared with those that received 40 mg Zn/kg of diet (P &amp;lt; 0.05). It can be concluded that Zn can improve laying performance, and can decrease aggressive behaviour.

Effect of dietary phytoextracts supplementation on growth performance and blood parameters of rainbow trout ( Oncorhynchus Mykiss W. ), cultivated in a recirculation system

The present research aimed to examine the effect of dietary phytoextracts supplementation on the growth performance, haematological (white blood cells, red blood cells, hemoglobin, hematocrit) and biochemical (glucose, urea, creatinine, total protein, albumin, ASAT, ALAT) blood parameters of rainbow trout (Oncorhynchus mykiss W.), cultivated in a recirculation system. The fish were divided into 6 groups: one control (C) and five experimental groups in whose food was added phytoextracts of curcumin (EC), paprika (EP), thyme (ET), oregano (EO) and garlic (EG). The inclusion of phytoextracts had no significant effect on growth parameters of fish from EC, EP, ET, EO and EG groups (P&gt;0.05). Statistically significantly lower feed consumption per unit weight gain was observed in EO group vs C (Р&lt;0.05). The phytoextract supplementation had significant influence on some of the haematological (white blood cells, red blood cells, hemoglobin) and biochemical (urea, creatinine, total protein, albumin, ASAT, ALAT) blood parameters of rainbow trout.

Efficiency of using the new domestic meat-egg hybrid for the production of food eggs in household farms

Aim. A detailed analysis of the egg production and economic effi ciency of using a new dual-purpose hybrid in a comparative aspect with the original forms. Methods. Standard zootechnical methods of estimating body weight, egg production and its intensity, egg weight, feed costs and livability of adult hybrid and purebred hens were used. The effects of heterosis on the main utility indicators and the European profi t ratio IOFC (Income Over Feed Cost), which displays the difference between the revenue from one layer and the cost of consumed food, was estimated. Results. Almost all studied indicators demonstrated the advantage of the hybrid over the original forms. The phenomenon of heterosis was observed in most studied indices – 5.7 % by precocity, 3– 7 % by mass of eggs, 12–14 % by egg production. Early puberty (on 2–16 days), more intensive build-up of egg production (by 3.3–4.2 %), improvement of its medium intensity by 4.6–9.8 % provided by hybrid laying hens per year of life which were 9–20 eggs superior than the origin forms. Due to the high productivity and low feed consumption per 10 eggs (2.1 kg versus 2.8 kg for the paternal form), the profi t ratio IOFC was also 28.7– 29.1 % higher for a hybrid. This indicates the expediency of using layers of a new hybrid combination for the production of food eggs in farming and household farms. Conclusions. The obtained zootechnical and eco- nomic indicators demonstrate the expediency of using layers of a new hybrid combination for the production of food eggs in farming and household farms.

Depression of leukocyte protein synthesis, immune function and growth performance induced by high environmental temperature in broiler chickens.

In tropical and semitropical regions, raising broiler chickens out of their thermal comfort zone can cause an added economic loss in the poultry industry. The cause for the deleterious effects on immunity and growth performance of broilers under high environmental temperatures is still poorly understood. Therefore, the aim of the current investigation was to evaluate the effect of heat stress on leukocytes protein synthesis and immune function as a possible direct cause of low performance in broiler chickens under such condition. In this study, 300 one-day-old male broiler chicks (Cobb500™) were randomly assigned into 2 groups with 5 replicates of 30 chicks each. From 21 to 42days of age, one group was exposed to non-stressed condition at 24°C and 50% relative humidity (control group), while the other group was exposed to heat stress at 35°C and 50% relative humidity (HS group). At 42days of age, blood samples were collected from each group to evaluate stress indicators, immune function, and leukocytes protein synthesis. Production performance was also recorded. Noteworthy, protein synthesis in leukocytes was significantly (P<0.05) inhibited in HS group by 38% compared to control group. In contrast, the phosphorylation level on threonine 56 site (Thr56) of eukaryotic elongation factor (eEF2), which indicates the suppression of protein translation process through altering the protein elongation phase, was significantly threefold higher in HS group than in control (P<0.05). In addition, an increase in stress indicators was markedly (P<0.05) presented in the HS birds by twofold increase in heterophil/lymphocyte (H/L) ratio and threefold increase in plasma corticosterone level compared to control. Furthermore, the immune function was significantly (P<0.05) suppressed in HS birds than control (0.99 vs. 1.88mg/mL plasma IgG, 89.2 vs. 148.0μg/mL plasma IgM, 4.80 vs. 7.20 antibody titer against SRBC, and 1.38 vs. 3.39 stimulation index of lymphocyte proliferation in HS vs. control group, respectively). Moreover, results on the broiler performance indicate that HS birds had a significant (P<0.05) lower body weight gain by 58%, lower feed consumption by 39%, higher conversion ratio by 27%, and higher mortality by more than three times, compared to control birds. In conclusion, our results demonstrate that the inhibition of leukocyte protein synthesis through increasing the level of eEF2 Thr56 phosphorylation may play a key role in the observed decrease in immune function and growth performance with the high mortality rate encountered in broiler chickens under heat stress environment.

Use of essential oils in broiler chicken production – a review

Abstract Biological activity of volatile plant metabolites is the property that can potentially find application in animal nutrition. Nowadays, the use of bioactive compounds is encouraged in many areas of industry and agriculture, since these substances have similar properties as withdrawn antibiotic growth promoters. Meat poultry production is focused on the maximization of performance parameters, namely rapid chicken growth with low feed consumption, and with the optimum health status of the flock. Essential oils can stimulate the growth and functioning of the body, which translates into both chicken’s health and enhanced production parameters. The substances are characterized by a range of effects, are easily biodegradable, and do not usually require a waiting period - hence they can be used in breeding broiler chickens. Given the increasing restrictions imposed on poultry production in terms of food safety and ethical aspects of husbandry, it seems appropriate to look for the use of new, natural substances to be applied in animal production. The article presents the characteristics of essential oils in this context, with a particular focus on their antimicrobial and immunostimulatory properties. The paper also describes production applications of essential oils tested in experiments on hybrid Ross 308 and Cobb 500 chickens.

Detection of QTL for traits related to adaptation to sub-optimal climatic conditions in chickens

BackgroundGrowth traits can be used as indicators of adaptation to sub-optimal conditions. The current study aimed at identifying quantitative trait loci (QTL) that control performance under variable temperature conditions in chickens.MethodsAn F2 population was produced by crossing the Taiwan Country chicken L2 line (selected for body weight, comb area, and egg production) with an experimental line of Rhode Island Red layer R- (selected for low residual feed consumption). A total of 844 animals were genotyped with the 60 K Illumina single nucleotide polymorphism (SNP) chip. Whole-genome interval linkage mapping and a genome-wide association study (GWAS) were performed for body weight at 0, 4, 8, 12, and 16 weeks of age, shank length at 8 weeks of age, size of comb area at 16 weeks of age, and antibody response to sheep red blood cells at 11 weeks of age (7 and 14 days after primary immunization). Relevant genes were identified based on functional annotation of candidate genes and potentially relevant SNPs were detected by comparing whole-genome sequences of several birds between the parental lines.ResultsWhole-genome QTL analysis revealed 47 QTL and 714 effects associated with 178 SNPs were identified by GWAS with 5% Bonferroni genome-wide significance. Little overlap was observed between the QTL and GWAS results, with only two chromosomal regions detected by both approaches, i.e. one on GGA24 (GGA for Gallus gallus chromosome) for BW04 and one on GGAZ for six growth-related traits. Based on whole-genome sequence, differences between the parental lines based on several birds were screened in the genome-wide QTL regions and in a region detected by both methods, resulting in the identification of 106 putative candidate genes with a total of 15,443 SNPs, of which 41 were missense and 1698 were not described in the dbSNP archive.ConclusionsThe QTL detected in this study for growth and morphological traits likely influence adaptation of chickens to sub-tropical climate. Using whole-genome sequence data, we identified candidate SNPs for further confirmation of QTL in the F2 design. A strong QTL effect found on GGAZ underlines the importance of sex-linked inheritance for growth traits in chickens.

Alleviating the environmental heat burden on laying hens by feeding on diets enriched with certain antioxidants (vitamin E and selenium) individually or combined.

The present study was designed to alleviate the negative biohazards of high ambient temperature on the productive performance and physiological status of laying hens. A total of 135 Bovans laying hens were distributed into nine groups in a 3×3 factorial design experiment. Basal diet was supplemented with vitamin E at levels of 0, 250, and 500mg /kg diet. Within each dietary vitamin E level, each diet was supplemented with sodium selenite as a source of selenium (Se) to supply 0, 0.25, and 0.50mg Se/kg diet. Results showed that supplementing layer's diet with 500mg vitamin E/kg was accompanied with the lowest feed consumption (FC) and feed conversion ratio (FCR). The interaction among vitamin E and Se levels exerted significant effects only on FC and FCR. Insignificant differences were observed in egg quality criteria due to the treatments studied. Increasing vitamin E level was associated with a gradual decrease in basophil count and an increase in monocytes. A gradual decrease in the count of each of heterophils, monocytes, and eosinophils was observed with the elevation in the dietary Se level. The combination among vitamin E and Se levels produced a significant effect on all hematological parameters studied. As vitamin E increased, a marked decrease in serum AST and a gradual increase in total lipids, total cholesterol, and calcium were observed. As the level of dietary Se increased, serum total protein, albumin, T4, total cholesterol, and total lipids increased. No significant impacts were detected for the interaction among vitamin E and Se levels on any of blood constituents determined except serum globulin, ALT, and calcium. In conclusion, the combination between vitamin E and Se showed a good ability to alleviate the harmful impacts of heat stress and produced the highest productive performance when compared with the other groups, which exhibit the synergistic effect between the two antioxidants.

Wyniki tuczu swin zywionych pasza z udzialem kiszonki z parowanych ziemniak�w

The study included 60 finishers of the F1 crossbreds (Polish Large White x Polish Landrace), a half of gilts and barrows. Animals were divided into two groups of 30 individuals each. The control group (K) amounted to pigs fed with a complete mixtures, while the experimental group (D) - was fed a mixture with the participation of silage from steamed potatoes (26% DM). The mixtures were prepared on the basis of their own cereal pellets and a concentrate. Fattening animals started at body weight of about 30 kg and continued to the average body weight of about 115 kg. The body weight of animals and the quantity of the consumed feed mixtures were recorded during the fattening period. Meatiness of carcasses was evaluated according to the current classification of the EUROP apparatus IM-03.The analysis has been subjected to the following features: total weight gain, fattening period, average daily weight gain, slaughter age and consumption of feed during the fattening and slaughter features: warm carcass weight, slaughter efficiency, fat thickness, the depth of loin muscle and meat content in the carcass. The assessment also includes: the sales value of porker in accordance with the evaluation of their carcasses according to the EUROP and the cost of feeding porker during the whole period of fattening. It has been shown that the pigs in group K had a higher growth rate and earlier reached the slaughter weight than pigs from group D (P<0.01), whereas group D demonstrated a lower feed consumption. Group K was characterized by thinner backfat, higher loin muscle and higher meatiness than the carcasses of pigs from the group D (P<0.01). Carcasses of finishers from the group K were qualified to the most valuable classes S, E, U whereas group D to class E, U, R and O. Lower costs of porker production were shows in group D, whereas in the group K a higher value from the sale was attained. Nutrition with the participation of silage from steamed potatoes was less favorable because of the lower slaughter value of the carcass, than while feeding with the complete mixtures.

Effects of Trichoderma fermented wheat bran on growth performance, intestinal morphology and histological findings in broiler chickens

This experiment investigated the effects of wheat bran fermented with Trichoderma pseudokoningii (FWB) on growth performance, intestinal morphology and the incidence of non-specific pathological lesions in broilers. In vitro experimental results showed that cellulase and xylananse activity of fermented wheat bran reached its peak at day 4 and solid-state fermentation (SSF) enhanced the reducing sugar content. In addition, the possibility of Trichoderma adhering to the broiler’s crop epitheliums was also discovered. A total of 180 day-old Ross 308 male broilers were randomly distributed into one of the three dietary groups until 35 d of age: basal diet (control), 10% of basal diet replaced with wheat bran (10% WB) or 10% of diet replaced with fermented wheat bran (10% FWB). Results showed that 10% FWB group had lower feed consumption than the others, but improved feed conversion ratio (FCR) for starter phase (1 to 21 d) when compared to the control group. Furthermore, 10% FWB group had significantly increased villus height and villus height/crypt depth ratio in the ileum compared to the control group. Coliform bacteria count in the ileum was lower in the 10% WB group than the control, however, there were no differences between the 10% WB and 10% FWB treatment groups in the C. perfringens count. There were no morphological changes or incidences of non-specific pathological lesions in the 10% FWB group. These results suggested that replacing 10% of a basal diet with fermented wheat bran could not only improve growth performance but also provide optimal intestinal morphology in broilers.

Effective levels of selenium in the feeding of growing quail meat production

The studies were conducted in growing quail meat production at the age of 1–35 days in the research laboratory of feed additives National University of Life and Environmental Sciences of Ukraine. The research goal was to establish effective levels of additional introduction of Selenium in fodder for growing quail by comparing them to some zoo–technical indicators. Five groups of 100 quails were formed. The quails of the Control Group were fed a standard diet without the inclusion of additional Selenium. The quails of the trial groups received a standard diet supplemented with selenium: group 2 – 0.1 mg, group 3 – 0.2 mg, group 4 – 0.3 mg and group 5 – 0.4 mg / kg feed. For a determine the effect of selenium on the productive qualities of quails was conducted taking into account their of preservation, feed intake, body weight is determined and calculated feed cost per 1 g of live weight gain. During the study established that the level of preservation quails high enough in the experimental groups, the best body weight was observed in animals consuming an additional 0.4 mg of Se, and the lowest feed consumption per 1 kg of growth – from poultry which were fed 0.2 mg Se. Thus, investigated of trace elements in the indicated doses increases the productivity of quails and decrease feed costs per 1 kg of live weight gain