Effects of age, weight, and housing system on prevalence of dead on arrival and carcass condemnation causes in laying hens

Evaluating the Economic Impacts of a Cage-Free Animal Welfare Policy in Southeast Asian and Indian Egg Production: A Systematic Review

Animal welfare is increasingly understood to be a key component of sustainable agricultural production. Southeast Asia and India are witnessing an emerging market for cage-free egg production. To evaluate the economic sustainability of cage-free policies in the region, it is critical to understand how this transition will affect farmers' costs and revenues. In this article, we provide an overview of the available information that can inform evaluations of cage-free egg production in Southeast Asia and India. Cage-free egg producers around the world tend to experience higher costs, but these costs are offset by higher revenues. As demand for cage-free eggs is stimulated in Southeast Asia and India by retailer or government policies, we expect that producers will be capable of meeting this demand. In Asia specifically, the dominant cost component is poultry feed. We conclude that the economic viability of egg production in the region is likely to be driven by feed prices and associated government policies, rather than production system per se.

Comparative Analysis of Animal Welfare in Three Broiler Slaughterhouses and Associated Farms with Unsatisfactory Slaughterhouse Results

The objective of this study was to assess the health and welfare of 70 commercial broiler flocks (transport batches) in three distinct slaughterhouses based on various indicators including emaciation, dirty feathers (DFs), footpad dermatitis (FPD), hock burn (HB), breast burn (BB), breast blister, breast ulcer, ascites, septicemia/abnormal color, cellulitis, extensive traumatisms, dead on arrival (DoA) and condemnation rate. Assessment scales ranging from 0 (absence) to 2 (severe) were used for DFs, FPD, and HB, while a 0 (absence) to 1 (present) scale was applied to BB, breast blisters, and breast ulcers. The prevalence of total condemnation causes (emaciation, ascites, septicemia/abnormal color, cellulitis, and extensive traumatism) and DoA were recorded and presented in percentages. Three flocks presented condemnation rates higher than 4% and 11 flocks presented DoA rates higher than 0.5%. Twenty-one flocks achieved grade 1 (warning) for FPD and 14 achieved grade 2 for FPD (alarm). Extensive trauma was observed in 0.01% of the slaughtered animals, and no flock reached the threshold of 2%. Breast blisters and breast ulcers lesions were not observed in the studied flocks. The significant positive associations observed for the presence of severe footpad dermatitis (FPD2), severe hock burns (HB2), and breast burns (BB1) indicate simultaneous occurrences. Absences of hock burns (HB0) and breast burns (BB0) were also associated. Eleven houses that obtained the worst results for welfare indicators at slaughterhouses were audited. FPD, HB, DoA, and the condemnation rate were the most crucial indicators for identifying farms with inadequate welfare conditions. These indicators should be systematically integrated into the welfare monitoring of broilers in slaughterhouses. Audits conducted on farms detected some noncompliance with regulatory welfare standards and suggested improvements in environmental and structural conditions, as well as the reduction in stocking densities and improvements in the water systems.

Multi-omics analysis reveals the molecular regulatory network underlying the prevention of Lactiplantibacillus plantarum against LPS-induced salpingitis in laying hens

BACKGROUND

Salpingitis is one of the common diseases in laying hen production, which greatly decreases the economic outcome of laying hen farming. Lactiplantibacillus plantarum was effective in preventing local or systemic inflammation, however rare studies were reported on its prevention against salpingitis. This study aimed to investigate the preventive molecular regulatory network of microencapsulated Lactiplantibacillus plantarum (MLP) against salpingitis through multi-omics analysis, including microbiome, transcriptome and metabolome analyses.

RESULTS

The results revealed that supplementation of MLP in diet significantly alleviated the inflammation and atrophy of uterus caused by lipopolysaccharide (LPS) in hens (P < 0.05). The concentrations of plasma IL-2 and IL-10 in hens of MLP-LPS group were higher than those in hens of LPS-stimulation group (CN-LPS group) (P < 0.05). The expression levels of TLR2, MYD88, NF-κB, COX2, and TNF-α were significantly decreased in the hens fed diet supplemented with MLP and suffered with LPS stimulation (MLP-LPS group) compared with those in the hens of CN-LPS group (P < 0.05). Differentially expressed genes (DEGs) induced by  MLP were involved in inflammation, reproduction, and calcium ion transport. At the genus level, the MLP supplementation significantly increased  the abundance of Phascolarctobacterium, whereas decreased the abundance of Candidatus_Saccharimonas in LPS challenged hens (P < 0.05). The metabolites altered by dietary supplementation with MLP were mainly involved in galactose, uronic acid, histidine, pyruvate and primary bile acid metabolism. Dietary supplementation with MLP inversely regulates LPS-induced differential metabolites such as LysoPA (24:0/0:0) (P < 0.05).

CONCLUSIONS

In summary, dietary supplementation with microencapsulated Lactiplantibacillus plantarum prevented salpingitis by modulating the abundances of Candidatus_Saccharimonas, Phascolarctobacterium, Ruminococcus_torques_group and Eubacterium_hallii_group while downregulating the levels of plasma metabolites, p-tolyl sulfate, o-cresol and N-acetylhistamine and upregulating S-lactoylglutathione, simultaneously increasing the expressions of CPNE4, CNTN3 and ACAN genes in the uterus, and ultimately inhibiting oviducal inflammation.

Lotus leaf extract can attenuate salpingitis in laying hens by inhibiting apoptosis

This study aimed to determine whether the lotus leaf extract (LLE) had the effect of treating salpingitis in laying hens. First, the salpingitis model was established by the method of bacterial infection. Differential genes between salpingitis and healthy laying hens were identified by transcriptome sequencing, and GO and KEGG enrichment analyses were performed. Groups of treatment of antibiotics and LLE were established to verify the feasibility of the lotus leaf extract in treating salpingitis. Furthermore, the active component and pharmacological effects of LLE were identified using the UPLC-Q-TOF-MS and network pharmacology technique. At last, the mechanism of LLE treating salpingitis was further evaluated by DF-1 cells infected with bacteria. The results showed that LLE significantly reduced the levels of TLR4 and IFN-γ (P < 0.05), accelerated the levels of IgA and IgG (P < 0.05), regulated the levels of SOD and MDA (P < 0.05) in laying hens with salpingitis. A total of 1,874 differential genes were obtained according to the transcriptome sequencing. It was revealed a significant role in cell cycle and apoptosis by enrichment analysis. In addition, among the 28 components identified by UPLC-Q-TOF-MS, 20 components acted on 58 genes, including CDK1, BIRC5, and CA2 for treating salpingitis. After bacterial infection, cells were damaged and unable to complete the normal progression of the cell cycle, leading to cell cycle arrest and further apoptosis formation. However, with the intervention of LLE, bacterial infection was resisted. The cells proliferation was extensively restored, and the expression of NO was increased. The addition of LLE significantly decreased cell apoptosis. The G1 phase increased, the S phase and the G2 phase decreased in the model group; after the intervention of LLE, the G1 phase gradually returned to the average level, and G2 and S phases increased. The mRNA expression levels of BIRC5, CDK1, and CA2 were consistent with the predicted results in network pharmacology. At the same time, the mRNA expression levels of Caspase-3 and Caspase-7 were reduced after added with LLE. The mRNA expression levels of TNF-α, TRADD, FADD, Caspase-8, Caspase-10, and Caspase-9 (P < 0.05), which would inhibit death receptor activation and decrease the apoptotic cascade, were upregulated after bacterial infection. However, the results in LLE groups were downregulated (P < 0.05). Meanwhile, the mRNA expression levels of BCL-2 in LLE groups were increased significantly compared with it in model group (P < 0.05). Notably, LLE administration inhibited apoptosis and regulated the cell cycle distribution in the salpingitis induced by bacterial infection. These results indicated that the LLE attenuated bacterial-induced salpingitis by modulating apoptosis and immune function in laying hens.

Causes of carcass condemnation in Norwegian aviary housed layers

BACKGROUND

Meat inspection data is commonly used to monitor health and welfare in commercial broiler production; however, less used in layers. Slaughterhouse records can provide insight into animal and herd health and identify important health and welfare challenges. To gain knowledge of health issues in commercial aviary housed laying hens, the aim of this repeated cross-sectional study was to describe the occurrence and causes of carcass condemnation, including dead-on-arrivals (DOA), in commercial aviary housed layers in Norway, and to explore seasonal patterns and correlation between DOA and number of carcass condemnations.

RESULTS

Data from January 2018 to December 2020 were collected from one poultry abattoir in Norway. In total, 759,584 layers were slaughtered during this period in 101 slaughter batches from 98 flocks and 56 farms. In total, 33,754 (4.4%) layers were condemned, including the DOA. The most common carcass condemnation causes were (percent of all slaughtered layers): abscess/cellulitis (2.03%), peritonitis (0.38%), DOA (0.22%), emaciation (0.22%), discoloration/smell (0.21%), acute skin lesions (0.21%) and ascites (0.17%). Regression analysis showed an estimated higher prevalence of total carcass condemnation during winter compared to the other seasons.

CONCLUSIONS

The three most common condemnation causes found in the present study were: abscess/cellulitis, peritonitis, and DOA. We found a large between-batch variation in causes of condemnation and DOA indicating that prevention might be possible. The results can be used to inform and guide further studies on layer health and welfare.

Oviduct Histopathology of Internal Laying and Egg-Bound Syndrome in Laying Hens

In the egg industry, common reproductive disorders, such as internal laying and egg-bound syndrome, not only reduce egg productivity but also cause deaths in severe cases. In this study, we focused on the oviduct histology of the pathogenesis of internal laying and egg-bound syndrome. We divided the aged laying hens into four groups according to the observation of the abdominal cavity and oviductal lumen: healthy, internal laying, egg-bound, and intercurrent. The percentages of healthy, internal laying, egg-bound, and intercurrent groups were 55%, 17.5%, 15%, and 12.5%, respectively. In all parts of the oviduct (i.e., infundibulum, magnum, isthmus, and uterus), the oviductal epithelium was composed of ciliated epithelial cells and secretory cells. The epithelial region lacking cilia was larger in the entire oviduct of the internal laying, and intercurrent groups than in the healthy group. In the internal laying, egg-bound, and intercurrent groups, significant T-cell infiltration was observed in the lamina propria of the entire oviduct. The morphological alteration of ciliated epithelial cells in the oviducts caused by inflammation may be the underlying cause of the pathogenesis of internal laying and egg-bound syndrome.

Time series evaluation of condemnation at poultry slaughterhouses enable to export in Southeastern Brazil (2009-2019): a tool for optimizing resources in the poultry production chain

BACKGROUND

Even with the technological advances in management, health and genetics applied to poultry farming worldwide, there is still a high rate of carcasses condemnation at slaughterhouses, which result in losses for the poultry production chain. Thus, this work aimed to evaluate the condemnation occurrence index (COI) and adjusted seasonal index (ASI) of poultry (turkey, griller, and heavy chicken) between 2009 and 2019, in a slaughterhouse enable to export in southeastern Brazil. Data were obtained from official spreadsheets from the Brazilian Federal Inspection Service (FIS) and used to calculate the COI, correlation analysis between the main causes of condemnation, and ASI assessments throughout the year.

RESULTS

Seven percent (55,594,318) of the poultry carcasses were condemned (partial or total), and the most frequent causes, contamination, and contusion/traumatic injury, amounted to 63.5% of the total condemnation. There was a trend of increasing condemnation throughout the time series evaluated, with COI varying between 45,282-149,809 condemnations per 1,000,000 poultry slaughtered. Considering the ASI, it was identified that for ascitic syndrome, July has a higher index value (1.63) than the months between January-June (P < 0.05).

CONCLUSIONS

The main causes of condemnation were contamination and contusion/traumatic injury, both technological causes. ASI showed that in July there is a greater carcasses condemnation due to ascitic syndrome than in the months between January and June. The variations observed in the ASIs can provide subsidies for preventive measures and optimization of human and financial resources, generating positive impacts on food safety, productivity, and profitability of the sector.