Applied Research Note: Effects of various concentrations of supplemental biochar on ileal digestible energy and live performance of broilers during an 8-wk production period

SUMMARY: The development and application of non-nutritive feed additives have increased over the past several years for many nutritional, functional, and health-related reasons. The reduced use of dietary antibiotics at subtherapeutic concentrations has created a need for readily available, cost-effective, and efficacious alternatives to help maintain broiler growth performance and gastrointestinal health in the absence of antibiotic growth promoters. Non-nutritive additives such as biochar have been reported in the literature to positively affect body weight gain in pigs and turkeys, but limited research has evaluated the effects of biochar supplementation in large broilers. These responses are likely related to its adsorptive capabilities which may provide a therapeutic effect by binding mycotoxins, bacterial toxins, antinutritional metabolites, or pathogenic bacteria in the gastrointestinal tract. This study evaluated the effects of feeding various concentrations (0.0, 0.5, 1.0, 1.5, or 2.0%) of a novel biochar product derived from the pyrolysis of pistachio shells on apparent ileal digestible energy and growth performance of broilers during an 8-wk production period. At 15 d of age, broilers fed diets with 2.0% supplemental biochar had a 10% lower apparent ileal digestible energy than those fed the diet without supplemental biochar. However, at 29 d of age, no differences in apparent ileal digestible energy were observed. Similarly, no differences in broiler growth performance were observed throughout the experiment. Thus, supplementing diets with higher concentrations of biochar (2.0%) may negatively affect apparent ileal digestibility of young broilers but overall biochar supplementation did not affect the growth performance of large broilers

Effect of photoperiod on physiological parameters in broiler chicks from placement to 7 d of age

SUMMARY: Photoperiod effects during the first 7-days posthatch have not been adequately investigated for broiler chicks, especially with modern genetics. Acclimation to the rearing environment (location of feed and water) has historically been the impetus for continuous or near-continuous photoperiods for broilers during the first 7 d. However, recent research has shown that a shorter photoperiod initiated from the day of hatch (20L:4D) does not result in any significant differences in live performance (crop fill, BW, BW gain, FI, FCR) compared to near-continuous lighting (23L:1D). Furthermore, excessive lighting during this critical developmental window may have detrimental physiological effects, which could ultimately inhibit full production potential and decrease overall health and welfare. This study examines the effect of a longer dark phase (scotophase) applied during the first 7-days posthatch on physiological parameters (melatonin, blood glucose, corticosterone). A total of 176 Ross 708 broiler chickens were reared in 2 trials to 7 d of age using 2 different lighting program treatments (20L:4D vs. 23L:1D) applied from day of hatch. Blood sampling was conducted at even intervals during the dark period at d 7. Melatonin production was significantly increased in the 20L:4D group, blood glucose levels maintained a consistent level throughout the dark period for the 20L:4D group, and corticosterone levels were not outside of the normal physiological range for either group. Increased scotophase length implemented as early as day of hatch may result in improved physiological function including growth, health indices, and productivity among others

Age-related effect of high-frequency LED lighting in laying hens on biochemical, enzymatical, and electrolytes variables

SUMMARY: A novel lighting system using high-frequency differential photostimulation developed for layer chickens was assessed for its effects on physiological response. In each of the 2 trials, a total of 320 ten-wk-old layer pullets were randomly allocated to 16 groups with 20 birds/group. Birds were weighed and randomly assigned to each of 4 cage banks in each of 4 rooms. Experimental treatments included the prototype LED lighting system and conventional 2700K LED bulbs. Photoperiod for the prototype system was 24L:0D per the manufacturer's recommendations and photoperiod for the conventional system followed the Hy-Line Management Guide. Blood samples (3 mL) were collected from the brachial wing vein into heparinized syringes within 45 s after birds were caught from 8 randomly selected birds per room for a total of 32 birds at each blood sampling day of placement, prior to point of lay, and at the termination of the study for a total of 96 birds. Plasma was separated from blood samples by centrifugation and used to determine the concentration of biochemical parameters and enzyme activities using an ACE-AXCEL automatic analyzer. Also, estradiol, follicle stimulating hormone, corticosterone, melatonin, T3, and T4 levels using Tosoh A1A-360 automatic analyzer. Results show that only uric acid (UA) and estradiol were affected by treatments. However, woa had significant effects on most examined variables. Plasma corticosterone was not affected by treatments and woa, indicating absence of physiological stress. In conclusion, using high-frequency LED lighting in layer hen houses does not negatively affect layer hens’ welfare

Effect of nutritional pen construction on the thermal performance of broilers

SUMMARY: Nutritional test pens are commonly used to segregate and geolocate birds in commercial-scale broiler houses to control spatial variation from the environment. Pens should subject test birds to similar environmental conditions as birds roaming free in the house, however, discussions on pen construction materials, design, and placement have focused on durability and handling with little regard for the pen's thermal environment. Simulated birds were constructed with a metal bowl and a light bulb heat source to mimic the heat generation of large commercial broilers. Bowl surface temperature (BST) was measured as a model for the surface temperature of a broiler housed in a nutritional pen. Effects of panel open area (100% (control), 89%, 85%, 70%, 50%, and 30%) and air velocity (2, 3, and 4 m/s) were factorially tested on BST in a wind tunnel. Panels with an open area of less than 70% were different (P < 0.0001) from free air (100% open area). There was a difference of 5°C (9°F) for BST between the most restrictive panel (30%) and free air (100%), demonstrating a large difference in the thermal environment that birds might experience if air is restricted. Air velocity treatments were different (P < 0.0001) with mean BST increasing as air velocity decreased. Panels should be constructed with open areas greater than 70% accounting for structural framing and other obstructions as well as expected dust accumulation. While pen durability and handling are important for on-site success, these parameters should not overshadow restrictive airflow pen designs that would potentially alter thermal environmental conditions in nutritional treatment comparisons.Mention of trade names or commercial products in this article is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the authors or the U.S. Department of Agriculture

Analysis and management of a pipeline safety information system. Final report

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Warning Effectiveness: What Do We Need to Know

The forensic area of practice for human factors engineers has brought into sharp focus the differences of opinion which exist regarding the effectiveness of warnings in bringing about safe behavior on the part of the user of a product. This paper addresses the major issues which the authors believe must be researched further to provide the definitive answers needed regarding the effectiveness of warnings in a variety of possible applications. A review of the literature will demonstrate that there are few studies of warning effectiveness per se, while there are many studies that address such issues as the need for warnings and presumed criteria for preparing effective warnings. It is suggested that further research is needed which addresses warning effectiveness in actual use situations, and in turn identifies the importance of such variables as stimulus energy level, information overload, risk perception, cost of compliance and the interaction of warnings, instructions and training.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline