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Simple Summary: In recent years, customers have increasingly favored eggs from cage-free systems, believing them to be healthier and more flavorful. It has become increasingly necessary to evaluate the genotypes raised in these systems in terms of production, quality, and economic viability. The aim of this study was to compare the performance, egg quality and economic aspects of Lohmann Sandy, Lohmann Brown and ATAK-S genotypes reared in a free-range system. In terms of performance and egg quality, the Lohmann Sandy and Lohmann Brown genotypes are better than the ATAK-S genotype. The ATAK-S genotype is better than other genotypes in terms of 50% egg production age. The difference between genotypes in terms of survival rate was statistically insignificant. We determined that the Lohmann Sandy genotype eggs had the lowest price. The aim of this study was to compare the performance, egg quality and economic aspects of laying hybrids of different genotypes in free-range system. In the study, three different laying genotypes (Lohmann Brown, Lohmann Sandy and ATAK-S genotype) were used. Each group consisted of four replicates and each replicate contained 20 hens. Egg production, broken–cracked egg ratio, egg weight, feed consumption, feed efficiency, and viability were determined as performance traits. Eggshell strength, Haugh unit, yolk color, and shell color were determined as egg quality traits. The costs of eggs were assessed for economic analysis. The Lohmann Sandy genotype produced more eggs than the Lohmann Brown genotype (p < 0.05). The ATAK-S genotype reached 50% egg production age sooner than other genotypes (p < 0.05). The Lohmann Sandy and Lohmann Brown genotypes produced fewer broken eggs and heavier eggs compared to the ATAK-S genotype (p < 0.05). The ATAK-S genotype consumed more feed than the Lohmann Sandy and Lohmann Brown genotypes (p < 0.05). The Lohmann Sandy and Lohmann Brown genotypes have better feed efficiency compared to the ATAK-S genotype (p < 0.05). Eggs from the Lohmann Sandy genotype exhibit greater resistance to breakage compared to those from other genotypes (p < 0.05). The highest quality of albumen was identified in the eggs of the Lohmann Brown genotype (p < 0.05). The yolk color of Lohmann Brown genotype eggs is darker than those of other genotypes (p < 0.05). The shell color of Lohmann genotype eggs is a darker brown compared to eggs of other genotypes (p < 0.05). The cheapest egg cost was determined from eggs produced from the Lohmann Sandy genotype (p < 0.05). According to the results obtained from our study, it would be more appropriate to prefer the Lohmann Sandy genotype in the free-range system. [ABSTRACT FROM AUTHOR]

Diverse immune responses in different chicken lines can result in varying clinical consequences following avian influenza virus (AIV) infection. We compared two widely used layer breeds, Lohmann Brown (LB) and Lohmann White (LW), to examine virus replication and immune responses against H9N2 AIV infection. The transcription profile in the spleen of H9N2-infected chickens was compared using a microarray. Confirmatory real-time RT-PCR was used to measure the expression of C-type lectin, OASL, and MX1 genes. Additionally, to investigate the role of chicken lectin receptors in vitro, two C-type lectin receptors (CLRs) were expressed in DF-1 cells, and the early growth of the H9N2 virus was evaluated. The LB chickens shed a lower amount of virus from the cloaca compared with the LW chickens. Different expression levels of C-type lectin-like genes were observed in the transcription profile, with no significant differences in OASL or MX gene expression. Real-time RT-PCR indicated a sharp decrease in C-type lectin levels in the spleen of H9N2-infected LW chickens. In vitro studies demonstrated that cells overexpressing CLR exhibited lower virus replication, while silencing of homeostatic CLR had no effect on AIV replication. This study demonstrated distinct immune responses to H9N2 avian influenza in LB and LW chickens, particularly with differences in C-type lectin expression, potentially leading to lower virus shedding in LB chickens. [ABSTRACT FROM AUTHOR]

ABSTRACT: Fermented rapeseed meal has the potential to partial replace soybean meal in feed mixtures for poultry without a negative impact on the health condition and performance of birds. This is due to the fact that the fermentation process can reduce the amount of antinutritional factors, improve the use of nutrients and impart probiotic properties to rapeseed meal. Therefore, this study was undertaken to investigate the effect of fermented rapeseed meal on the performance, egg quality, intestinal morphometry, the viscosity of intestinal content and total phosphorus availability. A total of 108 Lohmann Brown laying hens at 26 wk of age were used in the 90-day study. All hens were randomly divided into 3 treatment groups, with 12 replicates (cages) each, as follows: control group received no rapeseed meal, the URSM group received 3% unfermented rapeseed meal and the FRSM group received 3% fermented rapeseed meal. In the case of performance, egg traits, sensory evaluation of eggs, the viscosity of intestinal content and the availability of total phosphorus, if the distribution was normal, a 1-way analysis of variance was performed. If the distribution was not normal, the Kruskal-Wallis test was performed. In the case of histomorphometric evaluation of the intestine, if the distribution was normal, the Student t test for independent samples was performed. If not, a Mann-Whitney U test was performed. The performed analyses showed that the supplementation of fermented rapeseed meal had no negative effect on the performance of birds and the quality of eggs. Fermented rapeseed meal was also associated with improved histomorphometric parameters of the small intestine compared to the group receiving unfermented rapeseed meal in the feed. Laying hens from FRSM group were characterized by significantly lower viscosity of intestinal content (P < 0.05) compared to URSM group. Phosphorus in FRSM group was significantly more available to the birds (P < 0.05) compared to URSM group. These results suggest that supplementation with fermented rapeseed meal may be beneficial, especially in times of unstable prices of soybean meal and problems with its availability.

Semen quality plays a crucial role in poultry production; however, it may be impaired by the presence of numerous bacterial species. This study researched the impact of bacterial contamination of Lohmann brown rooster semen on the biochemical parameters of seminal plasma to evaluate its potential consequences on the sperm progressive motility. Semen was collected from 27 stud roosters, and the sperm concentration and progressive motility were measured using computer-assisted semen analysis (CASA). Seminal plasma was separated, and selected biochemical parameters were measured using commercially available assays. An aliquot of each semen sample was cultured, the colonies were counted and the MALDI Biotyper was used for bacterial identification. The samples were divided into three categories based on their sperm progressive motility and the data were compared and statistically evaluated. Moreover, Pearson’s correlation analysis was performed. The results showed that the lower the sperm progressive motility, the higher the level of colony-forming units. Moreover, sperm concentration was significantly higher (p < 0.05) in the group with the highest bacterial occurrence and the lowest proportion of progressively motile spermatozoa. Calcium, magnesium, creatinine, uric acid, alkaline phosphatase, and total proteins significantly changed in semen samples with the lowest proportion of progressive motility. In conclusion, seminal plasma biochemistry may mirror changes occurring in semen as a result of bacterial presence in the reproductive tract of poultry.

Semen quality plays a crucial role in poultry production; however, it may be impaired by the presence of numerous bacterial species. This study researched the impact of bacterial contamination of Lohmann brown rooster semen on the biochemical parameters of seminal plasma to evaluate its potential consequences on the sperm progressive motility. Semen was collected from 27 stud roosters, and the sperm concentration and progressive motility were measured using computer-assisted semen analysis (CASA). Seminal plasma was separated, and selected biochemical parameters were measured using commercially available assays. An aliquot of each semen sample was cultured, the colonies were counted and the MALDI Biotyper was used for bacterial identification. The samples were divided into three categories based on their sperm progressive motility and the data were compared and statistically evaluated. Moreover, Pearson's correlation analysis was performed. The results showed that the lower the sperm progressive motility, the higher the level of colony-forming units. Moreover, sperm concentration was significantly higher (p < 0.05) in the group with the highest bacterial occurrence and the lowest proportion of progressively motile spermatozoa. Calcium, magnesium, creatinine, uric acid, alkaline phosphatase, and total proteins significantly changed in semen samples with the lowest proportion of progressive motility. In conclusion, seminal plasma biochemistry may mirror changes occurring in semen as a result of bacterial presence in the reproductive tract of poultry. [ABSTRACT FROM AUTHOR]

Diverse immune responses in different chicken lines can result in varying clinical consequences following avian influenza virus (AIV) infection. We compared two widely used layer breeds, Lohmann Brown (LB) and Lohmann White (LW), to examine virus replication and immune responses against H9N2 AIV infection. The transcription profile in the spleen of H9N2-infected chickens was compared using a microarray. Confirmatory real-time RT-PCR was used to measure the expression of C-type lectin, OASL, and MX1 genes. Additionally, to investigate the role of chicken lectin receptors in vitro, two C-type lectin receptors (CLRs) were expressed in DF-1 cells, and the early growth of the H9N2 virus was evaluated. The LB chickens shed a lower amount of virus from the cloaca compared with the LW chickens. Different expression levels of C-type lectin-like genes were observed in the transcription profile, with no significant differences in OASL or MX gene expression. Real-time RT-PCR indicated a sharp decrease in C-type lectin levels in the spleen of H9N2-infected LW chickens. In vitro studies demonstrated that cells overexpressing CLR exhibited lower virus replication, while silencing of homeostatic CLR had no effect on AIV replication. This study demonstrated distinct immune responses to H9N2 avian influenza in LB and LW chickens, particularly with differences in C-type lectin expression, potentially leading to lower virus shedding in LB chickens.

This study aimed to characterize the bacterial profiles and their association with selected semen quality traits among two chicken breeds. Thirty Lohmann Brown and thirty ROSS 308 roosters were selected for semen quality estimation, including sperm motility, membrane and acrosome integrity, mitochondrial activity, and DNA fragmentation. The oxidative profile of the semen, including the production of reactive oxygen species (ROS), antioxidant capacity, protein, and lipid oxidation, were assessed as well. Moreover, the levels of pro-inflammatory cytokines, including tumor necrosis factor alpha (TNF-α), interleukins 1 and 6 (IL-1, IL-6) and C-reactive protein, as well as the concentrations of selected antibacterial proteins (cathelicidin, β-defensin and lysozyme) in the seminal plasma were evaluated with the enzyme-linked immunosorbent assay. The prevailing bacterial genera identified by the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry were Citrobacter spp., Enterococcus spp., Escherichia spp. and Staphylococcus spp. While the bacterial load was significantly higher in the ROSS 308 line (p < 0.05), a higher number of potentially uropathogenic bacteria was found in the Lohmann Brown roosters. Antimicrobial susceptibility tests revealed a substantial resistance of randomly selected bacterial strains, particularly to ampicillin, tetracycline, chloramphenicol, and tobramycin. Furthermore, Lohmann Brown ejaculates containing an increased proportion of Escherichia coli presented with significantly (p < 0.05) elevated levels of TNF-α and IL-6, as well as ROS overproduction and lipid peroxidation. Inversely, significantly (p < 0.05) higher levels of β-defensin and lysozyme were found in the semen collected from the ROSS 308 roosters, which was characterized by a higher quality in comparison to the Lohmann Brown roosters. In conclusion, we emphasize the criticality of bacteriospermia in the poultry industry and highlight the need to include a more complex microbiological screening of semen samples designated for artificial insemination. [ABSTRACT FROM AUTHOR]

This study aimed to characterize the bacterial profiles and their association with selected semen quality traits among two chicken breeds. Thirty Lohmann Brown and thirty ROSS 308 roosters were selected for semen quality estimation, including sperm motility, membrane and acrosome integrity, mitochondrial activity, and DNA fragmentation. The oxidative profile of the semen, including the production of reactive oxygen species (ROS), antioxidant capacity, protein, and lipid oxidation, were assessed as well. Moreover, the levels of pro-inflammatory cytokines, including tumor necrosis factor alpha (TNF-α), interleukins 1 and 6 (IL-1, IL-6) and C-reactive protein, as well as the concentrations of selected antibacterial proteins (cathelicidin, β-defensin and lysozyme) in the seminal plasma were evaluated with the enzyme-linked immunosorbent assay. The prevailing bacterial genera identified by the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry were Citrobacter spp., Enterococcus spp., Escherichia spp. and Staphylococcus spp. While the bacterial load was significantly higher in the ROSS 308 line (p < 0.05), a higher number of potentially uropathogenic bacteria was found in the Lohmann Brown roosters. Antimicrobial susceptibility tests revealed a substantial resistance of randomly selected bacterial strains, particularly to ampicillin, tetracycline, chloramphenicol, and tobramycin. Furthermore, Lohmann Brown ejaculates containing an increased proportion of Escherichia coli presented with significantly (p < 0.05) elevated levels of TNF-α and IL-6, as well as ROS overproduction and lipid peroxidation. Inversely, significantly (p < 0.05) higher levels of β-defensin and lysozyme were found in the semen collected from the ROSS 308 roosters, which was characterized by a higher quality in comparison to the Lohmann Brown roosters. In conclusion, we emphasize the criticality of bacteriospermia in the poultry industry and highlight the need to include a more complex microbiological screening of semen samples designated for artificial insemination.

A crossbreeding experiment was conducted between the Sinai (SI), an indigenous Egyptian strain, and the exotic Lohmann Brown (LB) breeds of chickens. A total of 790 chicks were produced in four genetic groups, namely SI x SI, LB x LB, SI x LB, and LB x SI. The objective was to estimate the direct additive effect (gi), individual heterosis (hi), and maternal additive effect (gm) for growth and reproduction traits. Direct additive effects were positive (P =0.01) for bodyweight (BW) at 4, 8, and 12 weeks old in favour of SI. For egg production traits, gi was positive for age at sexual maturity (ASM) and age at which the first 10 eggs were produced (P10), but negative for mean 10 egg production (MP10), egg number at 90 days (EN90), mean egg number at 90 days (MEN90), and egg mass (EM). The estimates of heterosis (%) were high for BW and daily gain except for BW0. Maternal effect estimates of BW and daily weight gain were significant (P <0.05) only for bodyweight at hatching (BW0), bodyweight at 4 weeks old (BW4) and daily weight gain from four to eight weeks old (DWG4-8). Thus, the Sinai and Lohmann Brown crossbreed produced favourable heterosis on the growth of the chicks. As an adapted indigenous strain, SI should be regarded as a dam line in crossing with LB, which has greater genetic potential for growth. Use of LB as a sire strain in conjunction with Sinai would increase egg production from the resulting hybrid chickens. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the productive performance and egg quality of Embrapa 051 lineage laying hens compared to a commercial line (Lohmann Brown) when subjected to different feeding programs. Trial consisted of a randomized complete block design, with four treatments: T1 - Lohmann Brown Line receiving 100% basal diet; T2 - Embrapa 051 Line receiving 93% basal diet; T3 - Embrapa 051 line receiving 100% basal diet; and T4 - Embrapa 051 lineage receiving 107% basal diet. The treatments had five replicates each. The basal diet was that recommended by the Lohmann Brown line manual. Variables of bird performance (egg weight, egg production rate, feed conversion per dozen eggs, energy conversion and egg mass) were analyzed, as well as internal egg quality (Haugh unit, yolk color, yolk percentage, and albumen percentage) and external egg quality (specific gravity, shell percentage, and shell thickness). All performance variables presented significant differences (P

The purpose of this study was to compare the performance and egg quality parameters of two layer hybrids (Lohmann Brown and Atak-S) which were reared in free-range system. The experiment was carried out with a total of 300 laying hens. From 18 to 50 weeks of age Lohmann Brown (LB) and Atak-S (AS) were housed in two groups of 150 hens in a poultry house with a stocking density of 7 hens/m2. The 2 trial groups were formed from 10 repetitions each consisting of 15 hens. At the 20, 30, 40 and 50 weeks of ages, the production performance and egg quality parameters were evaluated. Mean daily feed intake and feed efficiency through the trial were 111.2 g vs 124.3 g, and 2.46 vs 2.58 respectively for LB and AS hybrids (P

Systems based on dual-purpose poultry present an alternative for avoiding the culling of male layer chicks. However, controlled comparisons on the production characteristics of dual-purpose poultry are lacking. A modern dual-purpose type (Lohmann Dual; LD) and two traditional dual-purpose types (Schweizerhuhn and Belgian Malines) were compared to a standard layer type (Lohmann Brown Plus; LB) from the start of lay until week 33 of lay. In 3- and 4-week periods, the resilience of the hens to nutritional challenges was investigated with split-plot crossover design. At first the supplementation of synthetic methionine was omitted. Later, the hens were confronted by a reduction of the content of N-corrected metabolisable energy from 11.5 to 10.5 MJ/kg feed. The laying percentage of LD was initially similar to that of LB, but persistency and egg size were inferior resulting in a daily egg mass of 46.6 vs. 58.5 g in LB across the 33 weeks. Feed efficiency and egg quality of LD were in the range of LB. Laying percentage, egg size, feed efficiency and egg shell quality were poorer with the two traditional types. The omission of synthetic methionine and a reduction of 10% of the dietary content of metabolisable energy did not lead to a reduction in laying performance and egg quality in any hen type under the present conditions. Yet, stricter nutritional challenges imposed to minimise feed-food competition may turn to the advantage of modern and possibly traditional dual-purpose types, too. [ABSTRACT FROM AUTHOR]

Melanocortin receptor (MC4R) plays an important role in central melanocortin system and regulation of feed intake in birds. In this study the melanocortin gene (MC4R) was proposed as a candidate gene for egg production traits (yield and weight) in Lohmann Brown hens. DNA from blood samples was extracted to amplify the MC4R gene and the purified PCR products were sequenced. Alignment of sequence data from each group revealed that there is a variation detected in MC4R-1 at nucleotide 22 (T-G) (sense mutation) for high egg weight. Hens with the AB genotype produced significantly higher egg weight compared to hens with the AA genotype. There was no significant effect of this mutation on egg yield. The detected mutation and the analysis of egg production means revealed a significant association between MC4R polymorphism and egg weight. The MC4R-SNP could be considered as a useful marker in chicken selection especially for egg weight.

1. Although fattening dual-purpose types or male layer hybrid chickens appears more ethical than the common practice of culling day-old male layer chicks, the lower feed efficiency of these birds raises concerns. Replacing feed ingredients that compete with food production by those of lower value for human nutrition would be beneficial. 2. Lohmann Dual (LD), a modern dual-purpose type, Lohmann Brown (LB), a male layer hybrid, and Hubbard JA 957 (HU), a slow-growing broiler type, were fattened for nine weeks on two diets (control or −20% crude protein; n = 6 × 12 birds). Growth, carcass and meat quality were analysed. 3. Growth performance of HU exceeded that of LD and especially of LB. The growth depression caused by the low-protein diet fed to LD (−7%) was only half of that found in HU (−13%). The LD fed the control diet had the same feed efficiency as the HU fed the low-protein diet. Even the LB had a lower performance and feed efficiency with the low-protein diet in growth. There was a gradient in carcass properties (weight, dressing percentage, breast meat yield, breast proportion and breast angle) from HU to LD to LB, with some additional adverse effects of the low-protein diet especially in HU. There were some breed differences in fatty acid profile in the intramuscular fat. 4. In conclusion, the dual-purpose type used complied with regulations for Swiss organic poultry systems in terms of growth rate and was found to respond less when fed a low-protein diet than the slow-growing broiler type. The LB males were inferior in all growth and carcass quality traits. Future studies need to determine the exact protein and amino acid requirements of dual-purpose and layer hybrid chickens and the economic feasibility of the systems, especially for organic farming. [ABSTRACT FROM AUTHOR]

This study was carried out to compare indices of production and egg quality of two strains of laying hens (Lohmann Brown and Atak-S) housed in furnished cages. Lohmann Brown (LB) and Atak-S (AS) hens were housed in furnished cages (n= 700; 14 cages; 25 hens per cage; floor space 600 cm2/hen) from18 to 50 wk. Furnished cages included nests, perches and sandbathes. The hen day egg production, feed intake and egg weight of LB hens were higher than AS hens at week 40 and 50 (P<0.05). The AS had a significantly higher body weight (2074.1 g and 1900.2 g respectively) and lower mortality rate (7.1% and 12.7 % respectively); than LB hen at week 50 (P<0.05). However, no significant differences on egg quality parameters were noticed between LB and AS hens throughout the experiment (P > 0.05). In conclusion, our results showed that strain selection is important for productivity of laying hens rearing in furnished cages. Furthermore it can be concluded that performance of LB hens was better than AS hens in furnished cages. [ABSTRACT FROM AUTHOR]

The purpose of this study was to compare the performance and egg quality parameters of two hybrids of laying hens (Lohmann Brown and Atak-S) reared in free-range system. The experiment was carried out with a total of 300 laying hens. From 18 to 50 weeks of age Lohmann Brown (LB) and Atak-S (AS) were housed in two groups of 150 hens in a poultry house with a stocking density of 7 hens/m2. Feed intake and feed conversion rate during the all laying period were 111.2 g vs 124.3 g, and 2.46 vs 2.58 respectively for LB and AS genotypes (P<0.05). The AS had a significantly higher body weight (2200.5 g and 2022.2 g respectively) than LB hen at week 50 (P<0.05). There was no a significant difference concerning the egg production between two genotypes (P>0.05). However, egg weight was significantly higher in LB genotype than AS genotype (P<0.05). Similarly, no significant difference was found between two genotypes on egg quality characteristics throughout the experiment (P>0.05). In conclusion, our results showed that strain selection is important for productivity of laying hens rearing in free-range system. [ABSTRACT FROM AUTHOR]

In order to determine the properties of egg quality of light line hybrid Lohmann Brown, a research was conducted on a private poultry farm "Rakić komerc" doo, Batković, Bijeljina, the Republic of Srpska (BiH). During the production of eggs, special attention was paid to the four main production stages, namely: 20 th week SN20 (start load), 28 th week SN28 ("pixels" maksimum), 48 th week SN48 (center) and 72 nd week of hens age SN72 (the end of the production cycle). In these periods, the appropriate number of hens or eggs was taken by a random sample for research, analysis and statistical analysis of the established data for the tested parameters. In addition to the mass, individual egg quality traits were determined: egg weight (g), egg length (mm), egg width (mm), egg shape index (%), color scales (point), the purity of the shell (points) and yolk color (1-15 rosh, at hens age (SN20-72). The results showed that differences in the average weight of eggs originating from hens of different ages were statistically significant (P < 0.001). Analyzed commercial flock of laying hens producing eggs for human consumption, viewed as a whole, achieved satisfactory results in terms of egg quality parameters.

The objective of this study was to investigate the effects of dietary supplementation with different levels of arginine (Arg) on the immune response in the early growth stages of layer chickens. Three hundred 1-day-old male Lohmann Brown chickens were assigned to 5 treatments with 6 replicates each and 10 birds per replicate in a completely randomised design. The chickens were given a maize-soybean basal diet containing graded levels of Arg (1.19% (control), 1.44%, 1.69%, 1.94%, or 2.19% Arg). Blood, lymphoid organ and chyme samples were collected at d 42. Chickens that received 1.44% dietary Arg had a higher body weight than chickens in the other groups at d 42 (P<0.05). With the increase in dietary Arg, the relative spleen weight increased linearly (P<0.05), and the serum interferon-α (IFN-α) increased quadratically (P<0.05). However, no significant (P>0.05) effect was found on the concentrations of immunoglobulin A (IgA), interleukin-2 (IL-2) or Newcastle disease virus antibody (NDV-Ab) titres. The levels of secretory IgA (sIgA) increased quadratically (P<0.05) in the duodenum and linearly (P<0.05) in the ileum with the increase in Arg concentrations. It was concluded that levels of 1.44% dietary Arg led to the maximum body weight, whereas 1.69% of dietary Arg supplementation increased serum IFN-a and intestinal sIgA of Lohmann Brown chickens at d 42. [ABSTRACT FROM AUTHOR]

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A breed development strategy aimed at making exotic layers (Lohmann Brown) more productive under tropical environment using thermo-regulatory genes is underway at Akate Farms in Kumasi, Ghana. The present experiment was carried out to find out the effect of the genes on egg production in hot and humid environments. Three genetic groups comprising naked-neck, frizzle and their normally feathered sibs were obtained after successive generations of crossing between naked-neck and frizzle cocks and Lohmann brown hens. A total of 270 18-week-old pullets, 90 each of the 3 groups, were selected randomly and assigned to a completely randomized design experiment with 3 replicates, with 30 birds in each replicate group and kept up to a period of 72 weeks. The birds were kept in a partitioned open-sided deep-litter house constructed with sandcrete blocks with 30 pullets in each compartment. They were fed ad libitum with layer diets containing 18 % crude protein and 2,800 kcal ME/kg. Results obtained showed that the crossbred naked-neck and frizzle phenotypes produced eggs at a significantly ( P < 0.05) higher rates than their normally feathered sibs and also out-performed their normally feathered sibs in other egg production parameters measured, even though they all segregated from similar parents. This is an indication of the favourable effect of the genes on egg production under hot and humid environments. [ABSTRACT FROM AUTHOR]

The article discusses the study that examines the effect of the integration of naked-neck and frizzle genes into Lohmann Brown layers on egg production and quality in hot and humid environments. The study revealed significant superiority of Lohmann brown layers in terms of rate of lay, egg mass, egg weight and feed efficiency, and significant inferiority in egg quality. It showed naked-neck layers out-performing frizzle and normally feathered sibs in measured egg production parameters.

An abstract of the article "Observations on Main Quality Indices of Consumption Eggs Collected from Lohmann Brown Hen Hybrid," by Simona Paşcaláu and Marius Docolina is presented.