Telomere Length, Apoptotic, and Inflammatory Genes: Novel Biomarkers of Gastrointestinal Tract Pathology and Meat Quality Traits in Chickens under Chronic Stress (Gallus gallus domesticus)

This study was designed to examine the potentials of telomere length, mitochondria, and acute phase protein genes as novel biomarkers of gastrointestinal (GI) tract pathologies and meat quality traits. Chickens were fed a diet containing corticosterone (CORT) for 4 weeks and records on body weight, telomere length, GI tract and muscle histopathological test, meat quality traits, mitochondria, and acute phase protein genes were obtained at weeks 4 and 6 of age. The body weight of CORT-fed chickens was significantly suppressed (p < 0.05). CORT significantly altered the GI tract and meat quality traits. The interaction effect of CORT and age on body weight, duodenum and ileum crypt depth, pH, and meat color was significant (p < 0.05). CORT significantly (p < 0.05) shortened buffy coat telomere length. UCP3 and COX6A1 were diversely and significantly expressed in the muscle, liver, and heart of the CORT-fed chicken. Significant expression of SAAL1 and CRP in the liver and hypothalamus of the CORT-fed chickens was observed at week 4 and 6. Therefore, telomere lengths, mitochondria, and acute phase protein genes could be used as novel biomarkers for GI tract pathologies and meat quality traits.

197 Awardee Talk: Novel Management Strategies to Enhance Growth and Development of Feedlot Receiving Cattle

Feedlot receiving is one of the most critical phases within the beef production cycle, when cattle are exposed to several stress and health challenges that impact their welfare and productivity. These stressors include weaning, road transport, and commingling with different animals, which elicit adrenocortical and acute-phase protein responses known to impair cattle immunocompetence and growth. Accordingly, incidence of bovine respiratory disease (BRD) is elevated during feedlot receiving, despite efforts to minimize stress and vaccination protocols against BRD pathogens. With increased restrictions regarding the use of feed-grade antimicrobials in livestock systems, our research group has focused on developing management systems that minimize stress and enhance performance and immunity of receiving cattle. By providing all vaccines against BRD pathogens prior to feedlot entry, our group reported increased (P ≤ 0.05) vaccine efficacy, body weight (BW) gain, feed efficiency, and reduced BRD incidence during the receiving period compared to on-arrival or delayed vaccination. Reducing the number of cattle sources within receiving pens, as a manner to alleviate commingling stress, reduced (P = 0.04) the number of antimicrobials needed for cattle diagnosed with BRD to regain health. Administration of a bovine appeasing substance (BAS) to beef cattle at weaning alleviated (P ≤ 0.05) the resultant acute-phase protein response, enhanced humoral immunity against BRD pathogens, and improved BW gain during a 6-wk postweaning period. Likewise, BAS administration to steers upon feedlot arrival facilitated (P ≤ 0.05) early detection of BRD signs and lessened the BRD recurrence upon first antimicrobial treatment, resulting in improved (P ≤ 0.05) BW gain and feed efficiency during a 45-d receiving period. Collective, vaccinating cattle against BRD prior to feedlot arrival, reducing the number of cattle sources within receiving pens, and the use of BAS during stressful events are favorable strategies to enhance performance and immunity of feedlot cattle.

197 Awardee Talk: Novel Management Strategies to Enhance Growth and Development of Feedlot Receiving Cattle

Feedlot receiving is one of the most critical phases within the beef production cycle, when cattle are exposed to several stress and health challenges that impact their welfare and productivity. These stressors include weaning, road transport, and commingling with different animals, which elicit adrenocortical and acute-phase protein responses known to impair cattle immunocompetence and growth. Accordingly, incidence of bovine respiratory disease (BRD) is elevated during feedlot receiving, despite efforts to minimize stress and vaccination protocols against BRD pathogens. With increased restrictions regarding the use of feed-grade antimicrobials in livestock systems, our research group has focused on developing management systems that minimize stress and enhance performance and immunity of receiving cattle. By providing all vaccines against BRD pathogens prior to feedlot entry, our group reported increased (P ≤ 0.05) vaccine efficacy, body weight (BW) gain, feed efficiency, and reduced BRD incidence during the receiving period compared to on-arrival or delayed vaccination. Reducing the number of cattle sources within receiving pens, as a manner to alleviate commingling stress, reduced (P = 0.04) the number of antimicrobials needed for cattle diagnosed with BRD to regain health. Administration of a bovine appeasing substance (BAS) to beef cattle at weaning alleviated (P ≤ 0.05) the resultant acute-phase protein response, enhanced humoral immunity against BRD pathogens, and improved BW gain during a 6-wk postweaning period. Likewise, BAS administration to steers upon feedlot arrival facilitated (P ≤ 0.05) early detection of BRD signs and lessened the BRD recurrence upon first antimicrobial treatment, resulting in improved (P ≤ 0.05) BW gain and feed efficiency during a 45-d receiving period. Collective, vaccinating cattle against BRD prior to feedlot arrival, reducing the number of cattle sources within receiving pens, and the use of BAS during stressful events are favorable strategies to enhance performance and immunity of feedlot cattle.

Dietary zinc concentration and lipopolysaccharide injection affect circulating trace minerals, acute phase protein response, and behavior as evaluated by an ear-tag based accelerometer in beef steers

To assess plasma trace mineral (TM) concentrations, the acute phase protein response, and behavior in response to a lipopolysaccharide (LPS) challenge, 96 Angus cross steers [average initial body weight (BW): 285 ± 14.4 kg] were sorted into two groups by BW (heavy and light; n = 48/group), fitted with an ear-tag based accelerometer (CowManager SensOor; Agis, Harmelen, Netherlands), and stagger started 14 d apart. Consecutive day BW were recorded to start the 24-d trial (d -1, 0). Dietary treatments began on d 0: common diet with either 30 (Zn30) or 100 (Zn100) mg supplemental Zn/kg DM (ZnSO4). On day 17 steers received one of the following injection treatments intravenously to complete the 2 × 3 factorial: 1) SALINE (~2-3 mL of physiological saline), 2) LOWLPS: 0.25 µg LPS/kg BW or 3) HIGHLPS: 0.375 µg LPS/kg BW. Blood, rectal temperature (RT), and BW were recorded on d 16 (-24 h relative to injection), and BW was used to assign injection treatment. Approximately 6, 24 (d 18), and 48 (d 19) h after treatment BW, RT, and blood were collected, and final BW recorded on d 24. Data were analyzed in Proc Mixed of SAS with fixed effects of diet, injection, diet × injection; for BW, RT, dry matter intake (DMI), plasma TM, and haptoglobin repeated measures analysis was used to evaluate effects over time. Area under the curve analysis determined by GraphPad Prism was used for analysis of accelerometer data. Body weight was unaffected by diet or injection (P ≥ 0.16), but there was an injection × time effect for DMI and RT (P &lt; 0.05), where DMI decreased in both LPS treatments on d 16, but recovered by d 17, and RT was increased in LPS treatments 6 h post-injection. Steers receiving LPS spent less time highly active and eating than SALINE (P &lt; 0.01). Steers in HIGHLPS spent lesser time ruminating, followed by LOWLPS and then SALINE (P &lt; 0.001). An injection × time effect (P &lt; 0.001) for plasma Zn showed decreased concentrations within 6 h of injection and remained decreased through 24 h before recovering by 48 h. A tendency for a diet × time effect (P = 0.06) on plasma Zn suggests plasma Zn repletion occurred at a greater rate in Zn100 compared to Zn30. These results suggest increased supplemental Zn may alter rate of recovery of Zn status from an acute inflammatory event. Additionally, ear-tag-based accelerometers used in this study were effective at detecting sickness behavior in feedlot steers, and rumination may be more sensitive than other variables.

Comprehensive review of lipocalin 2-mediated effects in lung inflammation

Lipocalin-2 (LCN2) is an inflammatory mediator best known for its role as an innate acute-phase protein. LCN2 mediates the innate immune response to pathogens by sequestering iron, thereby inhibiting pathogen growth. Although LCN2 and its bacteriostatic properties are well studied, other LCN2 functions in the immune response to inflammatory stimuli are less well understood, such as its role as a chemoattractant and involvement in the regulation of cell migration and apoptosis. In the lungs, most studies thus far investigating the role of LCN2 in the immune response have looked at pathogenic inflammatory stimuli. Here, we compile data that explore the role of LCN2 in the immune response to various inflammatory stimuli in an effort to differentiate between protective versus detrimental roles of LCN2.

Immune properties of lactoferrin and its protective role in new coronavirus infection COVID-19

Thousands of studies have been conducted to study the new SARS-CoV-2 coronavirus, its infectious properties, transmission routes and all associated with the clinical manifestations and severity of COVID-19, especially with potential treatments. Lactoferrin is a member of the transferrin family, which is synthesized by epithelial cells of mammalian internal glands and is widely present in various secretory fluids such as milk, saliva, tears, and nasal secretions. Lactoferrin is one of the components of the innate humoral immunity, regulates the functions of immunocompetent cells and is a acute phase protein. Lactoferrin has strong antioxidant and anti-inflammatory properties. This review assesses the possibility of using lactoferrin as a supplement in immunocorrective therapy programs for viral diseases, including the novel coronavirus infection COVID-19.

The acute phase protein lactoferrin is a key feature of Alzheimer’s disease and predictor of Aβ burden through induction of APP amyloidogenic processing

Amyloidogenic processing of the amyloid precursor protein (APP) forms the amyloid-β peptide (Aβ) component of pathognomonic extracellular plaques of AD. Additional early cortical changes in AD include neuroinflammation and elevated iron levels. Activation of the innate immune system in the brain is a neuroprotective response to infection; however, persistent neuroinflammation is linked to AD neuropathology by uncertain mechanisms. Non-parametric machine learning analysis on transcriptomic data from a large neuropathologically characterised patient cohort revealed the acute phase protein lactoferrin (Lf) as the key predictor of amyloid pathology. In vitro studies showed that an interaction between APP and the iron-bound form of Lf secreted from activated microglia diverted neuronal APP endocytosis from the canonical clathrin-dependent pathway to one requiring ADP ribosylation factor 6 trafficking. By rerouting APP recycling to the Rab11-positive compartment for amyloidogenic processing, Lf dramatically increased neuronal Aβ production. Lf emerges as a novel pharmacological target for AD that not only modulates APP processing but provides a link between Aβ production, neuroinflammation and iron dysregulation.