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Summary: Eggshell quality is one of the most significant factors affecting the egg industry as it economically influences the quantity of saleable eggs. Eggshell quality can be improved through optimization of genotype, housing system, and mineral nutrition. This study aimed to compare genotypes and evaluate the morphological, physical, and chemical properties of eggs (weight, breaking strength, Haugh units, and dry matter) by hens of two different strains fed a 1940 and 2016 representative diet. Egg production was measured daily and there were four periods with 10-wk intervals in which eggs were analyzed starting at 30 wk and ending at 60 wk of age measuring quality parameters. This study was set as a 2 × 2 factorial. The factors consisted of 2 leghorn genetic strains that were a 2016 commercial layer (W36) and a 1940 random-bred leghorn line, then 2 diets based on 2016 and 1940 dietary standards. The treatment groups: 1) 2016 hen on 1940 diet, 2) 2016 hen on 2016 diet, 3) 1940 hen on 1940 diet, and 4) 1940 hen on 2016 diet had 8 replicates with 10 hens per treatment housing 2 hens per cage. Body weights were higher in the 2016 hens when compared to the 1940 hens, however, the feed conversion ratio fluctuated in hens with the 2016 hens on the 1940 diet consuming the most feed throughout the majority of the trial. The 1940s hens came into production later than the 2016 hens; however, the rate of production was consistent with one another. Oviduct and ovary weights were heavier in the 2016 hens when compared to the 1940 hens. Egg quality, both interior and exterior was greater in the 2016 hens when compared to the 1940 hens. Parameters measured demonstrated significant differences (P ≤ 0.05) among treatment groups suggesting that genetics and nutrition both played a role in production rate and egg quality.

SUMMARY: This study aimed to compare the performance of 2 quantitative ultrasound (QUS) devices and to investigate the possible relationship between bone density, measured by speed of sound (SOS), and the biomechanical properties of bone. The bone density of humerus and tarsometatarsus of 46, 29-week-old laying hens housed in conventional cages were measured with 2 QUS devices. After testing, the birds were humanely euthanized and their left tibiotarsus and tarsometatarsus were collected. The diameter of these bones was measured at mid-shaft. Bending moment and peak force were evaluated using a TA-HD Plus instrument. Statistical analysis was performed in JMP Pro 16. For all the analyses, significance was set at P< 0.05. There was poor agreement in the SOS results between both devices. There was a moderate positive linear correlation (r2 > 0.6) between bending moment and peak force. No significant linear correlation was observed between the bone diameter and the bending moment or the peak force, or between SOS or bone ash content and any of the mechanical properties measured. A nominal logistic fit model was used to compare low vs normal bone density to the biomechanical properties. A bone was defined to have low density if its SOS was below 1 standard deviation from the mean. A model that linked all 3 biomechanical properties (P = 0.0173) was significantly correlated with the density (low vs normal) of tibiotarsi. Furthermore, the hen's tarsometatarsus with a higher bending moment and lower peak force had an increased odds ratio of low density tibiotarsi (P = 0.0293). This study failed to demonstrate a relation between the SOS and biomechanical properties of bone. While QUS was noninvasive assessment, the devices provided minimal or no association with the mechanical or ash content of the bones. Testing and validation of noninvasive tools are needed to expand our understanding of bone health and offer early detection of bone loss mass in layer flocks in longitudinal studies to develop effective management and intervention strategies.

SUMMARY: Free-range poultry has become more popular due to consumer demands for improvements in animal welfare. The current study was conducted to determine the impact of paddock area stocking density on the egg and environmental microbiology of free-range laying flocks. A flock of brown egg layers was split and maintained at low (4.02 m2/bird) and high (2.01 m2/bird) paddock area stocking densities. Egg and environmental samples were taken every 7 to 9 wk between 20 and 52 weeks (wk) of age for the enumeration of aerobic bacteria, Enterobacteriaceae, yeast and mold as well as the presence of Campylobacter spp., Listeria spp., and Salmonella spp.At 20 wk, shells from high-density flocks had higher levels of aerobic bacteria (P < 0.02) and Enterobacteriaceae (P < 0.008) compared to low-density flocks. However, at wk 44, nestbox swabs from low-density flocks had higher levels of aerobic bacteria and Enterobacteriaceae. Nestbox swabs (P < 0.04) of high-density flocks (43.3%) had a higher prevalence of Campylobacter compared to low-density flocks (26.7%). Differences in prevalence of Listeria or Salmonella were not observed in this study.Previous studies had shown differences in range use and behavioral expression between low and high paddock area stocking density free-range hens. These differences could have impacts on egg and environmental microbiology. Further research is needed to investigate the relationship between hen behavior and egg and environmental microbiology of free-range laying flocks.

ABSTRACT: The objective of the study was to assess the efficacy of AZOMITE (AZM), a dacitic tuff breccia, in laying hens through egg quality and production parameters. A total of ninety six 73-wk-old Hy-Line W-36 commercial laying hens were randomly assigned to 2 dietary treatments, a control diet and the same diet containing 0.25% AZM, with 24 replicates of 2 hens/replication. From 73 to 77 wk, hens went through nonanorexic molt, and, from 77 to 85 wk, the hens were evaluated for egg production, eggshell quality, and bone health. At wk 85, tibiotarsi were collected for ash and mineral composition, ileal contents were collected for calcium, phosphorus, apparent metabolizable energy corrected for N (AMEn), and apparent nitrogen retention (ANR) evaluation. AZM-fed hens tended to have higher body weight (P = 0.07) from 82 to 83 and 84 to 85 wk, and higher hen day egg production than control (90.54 vs. 79.51%, P = 0.005) from 84 to 85 wk. In general, no differences were reported in feed intake, eggshell color, egg weight, albumen height, Haugh units, or eggshell thickness (P > 0.05). However, shell strength and elasticity were improved (P < 0.02) and yolk color was decreased (P = 0.03) in AZM-fed hens than control. Moreover, the digestibility of Ca, AMEn, and ANR was increased with 0.25% AZM compared to control (P < 0.01). Tibiotarsi P and Ca percentage were lower in AZM-fed birds than control (P < 0.01), without affecting bone strength and mineral density (P > 0.36). Therefore, the use of 0.25% AZM showed a potential in improving egg production and eggshell strength, while maintaining bone quality in post-molt laying hens.

SUMMARY: The popularity of free-range and organic poultry has increased in recent years due to consumer demands. A study was conducted to evaluate how the presence of organic dairy cattle manure could influence the environmental and egg microbiology of organic free-range laying flocks. A flock of brown egg layers was split and maintained in a rotational paddock grazing schedule of which was free of or exposed to organic dairy manure. Environmental and egg sampling occurred approximately every 8 wk between 20 and 44 wk of age for a presence of Listeria spp., Campylobacter spp., Salmonella spp., and enumeration of Enterobacteriaceae. There was no significant difference in the occurrence of Listeria spp., Campylobacter spp. and Salmonella spp. in environmental and egg samples between integrated and control grazing organic free-range flocks. A random sampling of Enterobacteriaceae colonies produced 211 viable isolates for biochemical identification. Seventeen genera, species, or serotypes were identified. There was a greater (P < 0.05) prevalence of total coliforms found on shell emulsion, egg contents, nest box straw, and forage samples from integrated organic free-range compared to control organic free-range flocks. Seasons of the year impacted microbial levels recovered from environmental and egg samples, with which summer having the highest level of all populations monitored. Additional studies are needed to fully understand the effect of mixed production rotational grazing on the prevalence of pathogens and Enterobacteriaceae on organic nest-run eggs and the grazing environment.

SUMMARY: This typescript has been written to provide a brief history of the commercial egg industry and the modern laying hen from the beginning of the 20th century to present. Certainly the hens’ husbandry and production practices will continue to change at the onset of this publication and thereafter. Farmers, egg distribution centers, and commercial egg companies in the U.S. have done an excellent job in keeping eggs affordable and in plentiful supply during the cited 100 yr plus (e.g., 1900 to present) of population growth, urban and suburban growth, and declining egg farmers and producers. Further, as industry efficiency and company consolidation increased, so did hen rearing practice misconceptions among U.S. consumers. The 2010 U.S. Census indicates that 1.6% of the US population is engaged in agriculture production, which feeds the remaining 98.4% of the population. This review highlights over 100 yr of table egg production in the U.S., beginning in 1900 when approximately 25% of the U.S. population was engaged in agriculture production.

A 78-year-old man with a history of neonatal anemia and jaundice and life-long photosensitivity was found to have harderoporphyria, as evidenced by increased porphyrins in urine, plasma, erythrocytes and feces including large amounts of harderoporphyrin in feces and erythrocytes. Two previously undescribed coproporphyrinogen oxidase (CPOX) mutations were identified, including a deletion of four amino acids in a region of the enzyme mutated in 7 of the 8 previously reported cases. This case increases the molecular heterogeneity of this rare porphyria, and illustrates that it should be considered as a cause of chronic photosensitivity and porphyrin elevation at any age.