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Wooden breast (WB) results in significant losses to the broiler industry due to reductions in meat quality. While the etiology of WB is unknown, it is believed to be associated with localized hypoxia and decreased lactate levels in skeletal muscles, indicating the presence of altered lactate metabolism in WB. We hypothesized that the expression levels of the major signaling molecules that control lactate metabolism, including lactate dehydrogenases (LDHA and LDHB) and monocarboxylate transporters (MCT1 and MCT4), were altered in WB. Therefore, the objectives of this study were to evaluate whether there were changes in mRNA and protein levels of LDHA, LDHB, MCT1, and MCT4 in WB compared to normal breast (NB) muscles. Biochemical analysis for LDH enzyme activity in NB and WB muscles was studied. MicroRNA375 (miR-375) expression, known to be inversely associated with LDHB protein expression in human cells, was also investigated. The level of LDHA mRNA was 1.7-fold lower in WB tissues than in NB tissues (P < 0.0001). However, the LDHA protein levels were similar in WB and NB tissues. In contrast, the levels of LDHB mRNA and protein were 8.4-fold higher (P < 0.002) and 13.6-fold higher (P < 0.02) in WB than in NB tissues, respectively. The level of miR-375 was not different between WB and NB muscles. The specific LDH isoenzyme activity that converted lactate to pyruvate was 1.8-fold lower in WB compared to NB tissues (P < 0.01). The level of MCT1 mRNA was 2.3-fold higher in WB than those in NB muscles (P < 0.02). However, this upregulation was not observed with MCT1 protein expression levels. The expression levels of MCT4 mRNA and protein were elevated 2.8-fold (P < 0.02) and 3.5-fold (P < 0.004) in WB compared to NB tissues, respectively. Our current findings suggest the potential roles of LDHB and MCT4 on lactate metabolism and provide a unique molecular elucidation for altered lactate homeostasis in WB muscles of broilers.

For poultry producers, chronic low-grade intestinal inflammation has a negative impact on productivity by impairing nutrient absorption and allocation of nutrients for growth. Understanding the triggers of chronic intestinal inflammation and developing a non-invasive measurement is crucial to managing gut health in poultry. In this study, we developed two novel models of low-grade chronic intestinal inflammation in broiler chickens: a chemical model using dextran sodium sulfate (DSS) and a dietary model using a high non-starch polysaccharide diet (NSP). Further, we evaluated the potential of several proteins as biomarkers of gut inflammation. For these experiments, the chemical induction of inflammation consisted of two 5-day cycles of oral gavage of either 0.25mg DSS/ml or 0.35mg DSS/ml; whereas the NSP diet (30% rice bran) was fed throughout the experiment. At four times (14, 22, 28 and 36-d post-hatch), necropsies were performed to collect intestinal samples for histology, and feces and serum for biomarkers quantification. Neither DSS nor NSP treatments affected feed intake or livability. NSP-fed birds exhibited intestinal inflammation through 14-d, which stabilized by 36-d. On the other hand, the cyclic DSS-treatment produced inflammation throughout the entire experimental period. Histological examination of the intestine revealed that the inflammation induced by both models exhibited similar spatial and temporal patterns with the duodenum and jejunum affected early (at 14-d) whereas the ileum was compromised by 28-d. Calprotectin (CALP) was the only serum protein found to be increased due to inflammation. However, fecal CALP and Lipocalin-2 (LCN-2) concentrations were significantly greater in the induced inflammation groups at 28-d. This experiment demonstrated for the first time, two in vivo models of chronic gut inflammation in chickens, a DSS and a nutritional NSP protocols. Based on these models we observed that intestinal inflammation begins in the upper segments of small intestine and moved to the lower region over time. In the searching for a fecal biomarker for intestinal inflammation, LCN-2 showed promising results. More importantly, calprotectin has a great potential as a novel biomarker for poultry measured both in serum and feces.

SUMMARY A rapid and effective means to clean and disinfect premises is needed by the poultry industry. We hypothesized that commercially available foaming disinfectants and cleaners applied via a compressed air foam system (CAFS) may be used to significantly reduce aerobic bacteria in a commercial caged layer complex. Six field trials were conducted to evaluate current industry cleaning and disinfection protocols and the proposed CAFS application. A commercially available chlorinated alkaline foaming cleaner (CHL/ALK) was applied in trials 1 and 2 by CAFS to one half of the house, and the other half of the house was not treated. The entire house was then washed with a high-pressure water rinse (HPWR). A commercially available peroxyacetic acid (PAA) in trials 3 and 4 or a 14% glutaraldehyde (HI GLUT)/2.5% quaternary ammonia (QAC) blended disinfectant in trials 5 and 6 was applied by CAFS to one half of a washed house. The remainder of the house was then treated with a 7% glutaraldehyde (LO GLUT)/26% QAC, which was spray-applied to cages by the integrator. Environmental swabs of drinker cups and cage floors were collected pre- and post-treatment to determine if aerobic bacteria were reduced. The HPWR and the CHL/ALK treatments did not consistently reduce bacteria on treated surfaces. Significant differences were observed with each of the CAFS applications of the PAA product, resulting in bacterial reductions of 1.83 to 2.27 log10 cfu/sample. Although inconsistent, differences (P

SUMMARY Layer cage cleaning and disinfection are important for disease prevention; however, published research is limited. The objective of this study was to determine the efficacy of commonly used products on soiled layer cages. Trial one was conducted at a university poultry research farm, and trial two was completed in a commercial pullet house. All products were mixed according to manufacturer recommendations. Treatments consisted of a negative control, a low-pressure water rinse (LPWR, garden hose), a high-pressure water rinse (HPWR, power washer), a soap, a chlorinated cleaner, a quaternary ammonium, a glutaraldehyde, a peroxyacetic acid, a phenolic, a potassium peroxymonosulfate, a hydrogen peroxide, and a quaternary/glutaraldehyde blend product. Swabs of cage floors were collected post treatment to determine if bacterial loads were reduced (P

Limited research has been performed to evaluate the effects of high-frequency electrical stunning (ES) methods on the lipid oxidative stability of the meat goose livers. This study was conducted to evaluate the effects of high-frequency-ES current intensities on lipid oxidative stability and antioxidant capacity in the liver of Yangzhou goose (Anser cygnoides domesticus). Forty 92-day-old male Yangzhou geese were randomly divided into five treatments (n = 8). Geese were not stunned (control) or exposed to ES for 10 s with alternating current (AC) at 500 Hz in a water bath. Current intensities were set at 30 V/20 mA (E30V), 60 V/40 mA (E60V), 90 V/70 mA (E90V), or 120 V/100 mA (E120V), respectively. The malondialdehyde level at day 0 was the highest in 120 V (p &lt, 0.05). Antioxidant enzymes&rsquo, activity on day 2 was the highest in E60V. The 1, 1-diphenyl-2-picrylhydrazyl free radical (DPPH&middot, ) elimination ability was lower in the E120V than that in the E60V at two days and four days postmortem (p &lt, 0.05). A combination of 60 V/40 mA/ 500 Hz/ 10 s per bird could be applied in the ES of Yangzhou geese to improve the lipid oxidative stability and antioxidant capacity in the livers.

Simple Summary Male layer chicks do not have economic value and are humanely killed after hatching. The layer industry is seeking alternative methods to humanely kill recently hatched male chicks. This study evaluated the use of gases or negative air pressure as a means of humane and viable alternatives to maceration. The treatments included carbon dioxide, nitrogen, reduced air pressure, and a negative control. The study showed that chicks exposed to treatments, gases or negative air pressure, did not differ significantly in terms of the physiological stress response. The use of carbon dioxide resulted in a faster onset of unconsciousness and ultimately death as compared to nitrogen or negative air pressure treatments. Abstract Hatched male layer chicks are currently euthanized by maceration in the United States. Public concerns on the use of maceration have led to the search for alternative methods. We hypothesized that gas inhalation and low atmospheric pressure stunning (LAPS) are viable and humane alternatives to instantaneous mechanical destruction. The objective of this study was to evaluate the physiological and behavioral responses of recently hatched male layer chicks when subjected to carbon dioxide, nitrogen inhalation, or LAPS. The study consisted of seven treatments: breathing air (NEG), 25% carbon dioxide (CO2), 50% CO2, 75% CO2, 90% CO2, 100% nitrogen (N2), or LAPS. Ten day-of-hatch, male layer chicks were randomly assigned to each treatment, and each treatment was replicated on ten different days. A custom-made vacuum system was used to reduce air pressure inside the chamber from 100.12 kPa to 15.3 kPa for the LAPS treatment. Serum corticosterone and serotonin levels were measured using commercially available competitive enzyme linked immunosorbent assay (ELISA). Latencies to loss of posture and motionlessness were determined from video recordings. The 25% and 50% CO2 treatments were discontinued after the first replication, as the majority of the chicks recovered. The chicks in the negative (NEG) group had significantly higher levels of corticosterone than the other four euthanasia treatments. On the other hand, the serotonin levels of chicks in the NEG group was significantly lower when compared to the other four euthanasia treatments. The latencies to loss of posture and motionlessness of chicks exposed to 75% and 90% CO2 were significantly shorter than those in the LAPS and N2 inhalation treatments. These data suggest that the stress responses of chicks to the CO2, N2, and LAPS treatments do not differ among each other. However, the CO2 inhalation method was faster in inducing loss of posture and motionlessness in chicks than the LAPS and N2 inhalation treatments.

Simple Summary Compressed air, detergent, and water make up compressed air foam. Our laboratory has previously reported that compressed air foam may be an effective method for mass depopulation of caged layer hens. Gases, such as carbon dioxide and nitrogen, have also been used for poultry euthanasia and depopulation. The objective of this study was to produce compressed air foam infused with carbon dioxide or nitrogen to compare its efficacy against foam with air and gas inhalation methods (carbon dioxide or nitrogen) for depopulation of caged laying hens. The study showed that a carbon dioxide-air mixture or 100% nitrogen can replace air to make compressed air foam. However, the foam with carbon dioxide had poor foam quality compared to the foam with air or nitrogen. The physiological stress response of hens subjected to foam treatments with and without gas infusion did not differ significantly. Hens exposed to foam with nitrogen died earlier as compared to methods such as foam with air and carbon dioxide. The authors conclude that infusion of nitrogen into compressed air foam results in better foam quality and shortened time to death as compared to the addition of carbon dioxide. Abstract Depopulation of infected poultry flocks is a key strategy to control and contain reportable diseases. Water-based foam, carbon dioxide inhalation, and ventilation shutdown are depopulation methods available to the poultry industry. Unfortunately, these methods have limited usage in caged layer hen operations. Personnel safety and welfare of birds are equally important factors to consider during emergency depopulation procedures. We have previously reported that compressed air foam (CAF) is an alternative method for depopulation of caged layer hens. We hypothesized that infusion of gases, such as carbon dioxide (CO2) and nitrogen (N2), into the CAF would reduce physiological stress and shorten time to cessation of movement. The study had six treatments, namely a negative control, CO2 inhalation, N2 inhalation, CAF with air (CAF Air), CAF with 50% CO2 (CAF CO2), and CAF with 100% N2 (CAF N2). Four spent hens were randomly assigned to one of these treatments on each of the eight replication days. A total of 192 spent hens were used in this study. Serum corticosterone and serotonin levels were measured and compared between treatments. Time to cessation of movement of spent hens was determined using accelerometers. The addition of CO2 in CAF significantly reduced the foam quality while the addition of N2 did not. The corticosterone and serotonin levels of spent hens subjected to foam (CAF, CAF CO2, CAF N2) and gas inhalation (CO2, N2) treatments did not differ significantly. The time to cessation of movement of spent hens in the CAF N2 treatment was significantly shorter than CAF and CAF CO2 treatments but longer than the gas inhalation treatments. These data suggest that the addition of N2 is advantageous in terms of shortening time to death and improved foam quality as compared to the CAF CO2 treatment.

Simple Summary Reportable diseases, such as avian influenza, spread rapidly among poultry, resulting in the death of a large number of birds. Once such a disease has been diagnosed at a farm, infected and susceptible birds are rapidly killed to prevent the spread of the disease. The methods to eliminate infected caged laying hens are limited. An experiment was conducted to study the effectiveness of foam made from compressed air, water, and soap to kill laying hens in cages. The study found that stress levels of the hens killed using compressed air foam in cages to be similar to the hens killed by carbon dioxide or the negative control. Hens exposed to carbon dioxide died earlier as compared to the foam methods. The authors conclude that application of compressed air foam in cages is an alternative to methods such as gas inhalation and ventilation shutdown to rapidly and humanely kill laying hens during epidemics. Abstract During the 2014–2015 US highly pathogenic avian influenza (HPAI) outbreak, 50.4 million commercial layers and turkeys were affected, resulting in economic losses of $3.3 billion. Rapid depopulation of infected poultry is vital to contain and eradicate reportable diseases like HPAI. The hypothesis of the experiment was that a compressed air foam (CAF) system may be used as an alternative to carbon dioxide (CO2) inhalation for depopulating caged layer hens. The objective of this study was to evaluate corticosterone (CORT) and time to cessation of movement (COM) of hens subjected to CAF, CO2 inhalation, and negative control (NEG) treatments. In Experiment 1, two independent trials were conducted using young and spent hens. Experiment 1 consisted of five treatments: NEG, CO2 added to a chamber, a CO2 pre-charged chamber, CAF in cages, and CAF in a chamber. In Experiment 2, only spent hens were randomly assigned to three treatments: CAF in cages, CO2 added to a chamber, and aspirated foam. Serum CORT levels of young hens were not significantly different among the CAF in cages, CAF in a chamber, NEG control, and CO2 inhalation treatments. However, spent hens subjected to the CAF in a chamber had significantly higher CORT levels than birds in the rest of the treatments. Times to COM of spent hens subjected to CAF in cages and aspirated foam were significantly greater than of birds exposed to the CO2 in a chamber treatment. These data suggest that applying CAF in cages is a viable alternative for layer hen depopulation during a reportable disease outbreak.

In a companion study, the effects of dietary antibiotic alternative and coccidial vaccination on the growth performance of male broilers have been reported. In this paper, the effects of dietary probiotics and coccidial vaccination on diversity and composition of cecal microbiota were investigated using a 3 (diets) × 2 (vaccinated or non-vaccinated) factorial setting of treatments. Three diets, including a corn and soybean-meal control diet, an antibiotic diet (a control diet supplemented with bacitracin and salinomycin), and a probiotic diet (a control diet supplemented with Bacillus subtilis) were provided to broiler chicken from day 0 to 42. To simulate an Eimeria challenge in the field, all chicks were gavaged with a 20× dose of commercial coccidial vaccine containing live Eimeria oocysts on day 14. Cecal contents were collected on day 42. High-throughput sequencing of the 16S rRNA gene was used to determine microbial diversity and composition. Coccidial vaccination to broilers reduced bacterial diversity (Shannon index) of the cecal microbiota. There was a significant interaction between the dietary additive and coccidial vaccination on the observed bacterial species number. Diets supplemented with B. subtilis increased bacterial species of non-vaccinated broilers but decreased bacterial species of vaccinated broilers. In contrast, diets supplemented with antibiotics reduced bacterial species of broilers from both groups. Interactions between dietary additive and coccidial vaccination were also observed on microbial composition. Vaccinated broilers fed the B. subtilis diet exhibited the lowest Firmicutes percentage and highest Bacteroidetes percentage within the microbial community. In addition, vaccinated broilers fed the B. subtilis diet exhibited the highest Rikenella microfusus percentage. From this study, the coccidial vaccination on the day of hatch reduced the microbial diversity of broilers at a later age. The inclusion of B. subtilis-probiotics in the feed of vaccinated broilers may reduce microbial diversity in cecal content by increasing the proportion of a predominant bacterial species, R. microfusus, in the microbial community.