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Simple Summary: There are many factors that can cause stress in poultry, but one of the most significant is high temperatures in the environment, which can make production difficult. It is important to assess the impact of heat stress (HS) on breeder ducks and their offspring (F1 generation) to identify biomarkers that can measure the response of poultry to HS effectively. This approach can reveal both physical and genetic characteristics that can serve as useful markers to determine the susceptibility or tolerance of different poultry breeds to HS. The results of our study indicated that exposing the parents to HS resulted in heightened Hypothalamic–Pituitary–Adrenal (HPA) axis and fear responses in their offspring. We concluded that the maternal hormones that are deposited into eggs during HS may influence the early programming of the brain, leading to alterations in the HPA and behavioral response in the F1 generation. The effects of HS on the welfare of poultry have been reported to have a transgenerational effect on phenotype plasticity. The goal of our experiment was to determine whether parental exposure to HS would impair the performance, HPA axis response, or behavior of their offspring. We treated adult drakes and hens (n = 80 ducks/treatment) at peak lay with HS or the control temperature for 3 weeks and incubated eggs collected from the last 3 days of the experiment. We utilized 76 ducklings/parental treatment group: control (CON-F1) and HS (HS-F1). Weekly data for body weights, body condition scores (BCSs), and novel object test (NOT) were collected. At 3 weeks of age, the ducks (n = 6/treatment) were subjected to adrenocorticotropic hormone (ACTH/cosyntropin, 0.0625 mg/kg) challenge or vehicle as the control. Blood samples were collected at 0, 1, 2, 3, and 4 h relative to treatment for serum glucocorticoid and heterophil-to-lymphocyte ratio (HLR) analyses. All injected birds were euthanized with pentobarbital on the second day relative to ACTH administration, and the spleen and bursa were removed and weighed immediately. Duck level analyses were completed using one- or two-way ANOVA as appropriate. BCSs were analyzed using a chi-squared test. The HS-F1 ducks had a lower hatch weight (p < 0.05) compared with the CON-F1 ducks but no significant difference in growth rates during the 5-week period. NOT (n = 4) analyses showed that the HS-F1 ducks had a greater fear response (p < 0.001) compared with the CON-F1 ducks. Similarly, an ACTH stimulation test showed that the HS-F1 ducks had significantly (p < 0.05) heightened corticosterone and HLR responses compared with the CON-F1 ducks. The HS-F1 ducks showed altered baseline and ACTH-stimulated levels of cortisol compared with the controls. Our data suggest that parental exposure to HS impacts the HPA response and fearfulness of the F1 generation in Pekin ducks. [ABSTRACT FROM AUTHOR]

Teachers may be hesitant to implement STEM-based agriculture programs due to their perceived low self-efficacy in the subject area. More deliberate professional development resources for educators can be refined by understanding how their beliefs impact students' learning and interest. The objective of this study was to determine how teachers' previous knowledge and self-efficacy in agriculture impacted student interest in the turkey industry. Four hundred eighty-two elementary students enrolled in the POULT program across 23 Indiana classrooms (17 teachers) in the fall of 2021. Students completed the program (online modules, interactive notebook, and class project) over six consecutive school days. Student situational interest was measured two times throughout the program. Teacher selfefficacy, previous agricultural experience, and knowledge of turkey industry were assessed at the start of the program (70.59% response rate). Teachers showed low selfefficacy in poultry content knowledge and high self-efficacy in engagement. Their agriculture experience positively increased their self-efficacy to motivate students to learn about turkey production. Additionally, teachers' instructional self-efficacy impacted students' situational interest. Overall, teachers found the program to be a positive way to engage students in agriculture. However, time commitments and technology issues may prevent them from implementing the program again in the future. [ABSTRACT FROM AUTHOR]

Galanin-like peptide (GALP) is expressed in the arcuate nucleus and is implicated in the neuroendocrine regulation of metabolism and reproduction. To investigate the physiological significance of GALP, we generated and characterized a strain of mice with a genetically targeted deletion in the GALP gene [GALP knockout (KO) mice]. We report that GALP KO mice have a subtle, but notable, metabolic phenotype that becomes apparent during adaptation to changes in nutrition. GALP KO mice are indistinguishable from wild-type (WT) controls in virtually all aspects of growth, sexual development, body weight, food and water consumption, and motor behaviors, when they are allowed unlimited access to standard rodent chow. However, GALP KO mice have an altered response to changes in diet. 1) Male GALP KO mice consumed less food during refeeding after a fast than WT controls (P < 0.01). 2) GALP KO mice of both sexes gained less weight on a high-fat diet than WT controls (P < 0.01), despite both genotypes having consumed equal amounts of food. We conclude that although GALP signaling may not be essential for the maintenance of energy homeostasis under steady-state nutritional conditions, GALP may play a role in readjusting energy balance under changing nutritional circumstances. reproduction; metabolism; knockout; obesity; body weight

Elementary students have minimal exposure and understanding of the farm to fork process. Exposure to agricultural curricula is critical to increase agricultural literacy and awareness of where food comes from. The objective of this study is to investigate student interest, awareness, and literacy gains after completing an online STEM-based turkey curriculum. In Fall 2021, the POULT program was implemented in 23 4th and 5th grade classrooms across Indiana with a total of 472 students enrolled and a 53.81% response rate. Students completed five online modules, an interactive notebook, and a class project over six consecutive school days. Demographic information, individual interest, agricultural content questions, and situational interest were measured at various time points throughout the program. Results indicated that student content scores increased at the end compared with beginning scores (6.94 vs 9.70, P< .001). Additionally, students’ individual interest, prior knowledge of agriculture, and agricultural experiences impacted their situational interest. Novelty and attention demand were high throughout completion of the POULT Program. Students enjoyed completing the online digestion simulation game and learning about the farm to fork process. In conclusion, online STEM-based agriculture programs can be a positive way to increase students’ interest and knowledge of agriculture. [ABSTRACT FROM AUTHOR]

Management choices during the pullet phase can affect behavior, welfare, and health later in life, but few studies have evaluated the pullet phase, particularly in extensive housing systems. This study was a 2 × 2 factorial randomized complete block design (RCBD) with two strains and two stocking densities. The Lohmann LB-Lite and Lohmann LSL-Lite were housed on the floor at high-stocking density (619-670 cm 2 /bird) and low-stocking density (1249-1352 cm 2 /bird), which changed with age from 2 to 16 weeks of age (WOA). Bird-based measures of appearance, blood parameters, organ measurements, and production values were evaluated. Stocking density alone affected ( p < 0.05) only relative bursal weight (% of body weight)-3.32% in the low-density versus 3.08% in the high-density group. High-stocking density was correlated with decreased uniformity (high-89.33 ± 0.24%; low-90.41 ± 0.24; p < 0.02) and worse feather coverage in the brown strain. High-stocking density was correlated with greater uniformity (High-90.39 ± 0.24%; Low-88.47 ± 0.24%; p < 0.001) and better feather coverage in the white strain. This study's feed conversion ratio (FCR) was improved by 0.07 in the low-stocking density for both strains. The remaining parameters were affected by strain and age only. Thus, while stocking density effects vary slightly depending on the strain used, cage-free pullets had limited negative effects at both the high and low-stocking densities tested in this study; there were few to no changes in the numerous bird-based welfare parameters tested.