Science topic

Thermal Biology - Science topic

Explore the latest questions and answers in Thermal Biology, and find Thermal Biology experts.
Questions related to Thermal Biology
  • asked a question related to Thermal Biology
Question
7 answers
Traditional and non-immersive computerised methods incorporate the employment of static and simple stimuli within a highly sterilized environment, while the ecologically valid tests which are currently in use do not adequately reflect the complexity of real-life situations. In contrast, immersive virtual reality (VR) enables the implementation of dynamic stimuli and interactions within a realistic environment, offers a high degree of control over the environment and the procedures involved. However, there is a scarcity of implementing immersive VR in conjunction with established neuroscientific tools such as neuroimaging tools (e.g., magnetoencephalography, electroencephalography, transcranial magnetic stimulation, and functional near-infrared spectroscopy) and physiological measurements (e.g., thermal camera, galvanic skin response, electromyography, and eye-tracking). I would like to request from researchers, who have already implemented any of the aforementioned neuroscientific tools in conjunction with immersive VR, to share their insights regarding their advantages and disadvantages of using these tools in immersive VR research paradigms.
Relevant answer
Answer
Mahdi Ebnali
Jimmy Y. Zhong
Sebastian Koenig
Confounding Factors
Head-mounted devices (HMDs) are implemented to achieve a highly immersive virtual reality (VR). However, the VR may induce adverse symptoms and effects (VRISE; cybersickness) such as nausea, disorientation, dizziness, instability, and fatigue. The presence of VRISE has modulated substantial decline in reaction times and overall cognitive performance, as well as increase body temperature and heart rates. Also, the presence of VRISE robustly increases cerebral blood flow and oxyhemoglobin concentration, the power of brain signals, and the connectivity between stimulus-response brain regions and nausea-processing brain regions. Thus, VRISE could be considered confounding variables, which significantly undermine the reliability of neuropsychological, physiological, and neuroimaging data. VRISE are frequently derivatives of VR hardware and/or software inadequacies, e.g., an HMD with a low refresh rate < 75Hz, or a low resolution < 960 x 1080 sub-pixels per eye; while a VR software should have an ergonomic navigation and interactions systems. So, do you have considered the confounding effect of VRISE? Do/did you intend to provide data pertinent to the intensity of VRISE in your population?
p.s.: the confounding effect of VRISE was studied in our recent technological review and meta-analysis of neuroscientific/psychological studies. https://www.frontiersin.org/articles/10.3389/fnhum.2019.00342/abstract
  • asked a question related to Thermal Biology
Question
6 answers
I am work with team from National Research Centre, cell biology Dep. and Animal Production Dep. I interest at poultry breeding and genetics "
The Ministry of Higher Education and Scientific Research of the Arab Republic of Egypt and the Ministry of Foreign Affairs of the French Republic have signed a Memorandum of Understanding for launching a bilateral program for scientific cooperation, named IMHOTEP, with the aim of facilitating, strengthening and developing scientific cooperation between the Egyptian and French researchers working at universities, research centers or institutes in both countries. The program covers bilateral research projects and scientific symposia involving researchers of the two countries in every scientific field.
The Academy of Scientific Research and Technology (ASRT) will be in charge of the administrative part of the program from the Egyptian side, while Campus France will be in charge of the administrative part from the French side. An Egypt-France Joint Board is established to review, assess and make specific recommendations concerning scientific and technological cooperative activities.
The Egyptian-French scientific program is based on a call for proposals jointly defined and simultaneously presented to Egyptian and French administrators. Egyptian researchers should submit their proposals to ASRT, while French researchers should electronically submit their proposals to Campus France. ASRT and Campus France will be responsible for sending the proposals for evaluation and consequently develop a priority list of approved proposals. This list will be submitted to the Joint Board for final selection.
Duration The maximum duration of a research project will not exceed two years. Annual progress report must be submitted jointly by the Egyptian and French researchers before the 30th of August; based upon the evaluation of this report, the joint board will determine the continuation of funding the project. Also a financial report must be submitted by the Egyptian researchers. At the end of the project, a final joint report must be submitted by the Egyptian and French researchers to their respective administration unit.
📷The research project is partially funded by the Academy of Scientific Research and Technology (a maximum of L.E. 200,000 per project for 2 years) where the grant offered by the Academy to the Egyptian side covers the expenses of travel for the Egyptian participants and the accommodations (including transportation in Egypt) for the French participants during their visits to Egypt. Meanwhile, the expenses of executing the research are provided by the cooperating Egyptian Institute (or any other sponsor that must be specified).
On the other hand, Campus France would cover the expenses of the travel (airfare) for the French partners as well as the accommodation expenses for the Egyptian partners during their visits to France. Duration of visits must not exceed 45 days.
Who can apply Egyptian and French researchers working at governmental or private universities, research centers or institutes in both countries are eligible to jointly apply ( junior researchers in particularly those who have acquired their Ph.D. within the last five years or may be enrolled in the Ph.D. program.) Researchers who have already implemented a project within Imhotep program are not entitled to submit a new proposal before passing two years after the end of the first project.
Relevant answer
Answer
I would suggest you to contact some people from INRA GABI unit https://www6.jouy.inra.fr/gabi_eng/ . They have at least two teams which are working with poultry genetics: GIS and PSGen.
  • asked a question related to Thermal Biology
Question
6 answers
Much of the previous heat tolerance research tends to focus on athletic/performance based populations. Moran's (2007) HTT seems to be the most widely used and referred to. Is anyone aware of, or had experience of using a heat tolerance test with specific populations i.e. Fire service, military, miners etc.  
Relevant answer
Answer
Thanks Jonathan.
Yes i've seen this document. Got some interesting bits in it. Have you used any of these tests? There doesn't appear to be any specific heat stress/tolerance test suggestions. 
  • asked a question related to Thermal Biology
Question
4 answers
Attached Figure is showing the thermal release of entrapped drug. Free drug, Free nano-particle and entrapped drug (Np+drug) is determined at different temperature (25-300 C). Why the drug lose its UV-Vis absorbance when it was entrapped in nano-particle?!!?
Relevant answer
Answer
Hello Pashandi,
I saw that your nanoparticle doesn't absorve on UV-Vis, so I believe it is Silica or something like that.
If I undertood, the free drug is inside of nanoparticle. If it is inside, the free drug is not interacting with the light. The suface of nanoparticle is blinding it. 
And others cases, when a molecule adsorbs on nanoparticle surface, it may not appear on UV-Vis cause it's bonding properties may change.
It is just an Idea...
  • asked a question related to Thermal Biology
Question
4 answers
Hello,
Can somebody share me the experiences of using the thermal camera for the human body temperature mapping? Currently, I am engaged in the research work related to human thermal comfort inside the automobile cabin with the FLIR SC 645 IR Camera of sensitivity 7.5-13 micrometer and spatial resolution 0.41 mrad. Will this be appropriate one for human body temperature mapping? If not, what could be the best one? 
Relevant answer
Answer
Your camera is good enough. you can go ahead without any issues.
From experience, I can say selection of experimental conditions are more important. Even mid wavelength cameras are also good enough for human body monitoring. The spatial resolution is altogether a different issue. More than anything it depends on your lens angle and subject to camera distance. I am considering your lens is fixed. Then the only option would be to play with distance provided you have enough clearance.
  • asked a question related to Thermal Biology
Question
1 answer
As a part of my M.tech thesis, I need some thermal images of oral cavities. Is there any database for oral thermal images?
Relevant answer
Answer
Our article published in peer-reviewed Journal "Communicative & Integrative Biology". A few major points discussed in the paper:
(1) Brain is not the source of consciousness.
(2) Consciousness is ubiquitous in all living organisms, starting from bacteria to human beings.
(3) The individual cells in the multicellular organisms are also individually cognitive entities.
(4) Proposals like “artificial life”, “artificial intelligence”, “sentient machines” and so on are only fairytales because no designer can produce an artifact with the properties like internal teleology (Naturzweck) and formative force (bildende Kraft).
(5) The material origin of life and objective evolution are only misconceptions that biologists must overcome.
  • asked a question related to Thermal Biology
Question
8 answers
We are a biomedical lab studying burns. There are insulated devices which drop in temperature when applied to a model of human skin, and the equation implies that 1 calorie drop (be it from 350 to 349 degrees or 10,000 degrees to 9,999 degrees) is equivalent in effect - just maybe the time to do the transfer is super low in the super high temperatures.
We know that there are probably other effects - i.e. super high temperatures may denature nearby protein based molecules in practice; but we doubt even the heat transfer itself is completely equivalent at great differences in temperature. While we believe in conservation of energy, we suspect that especially in a biological system the 'flow' is messier, maybe with the nearby molecules not being able to transfer the heat perfectly through deeper into the tissue at higher temperatures etc... We just don't know how to approach the question well enough to find literature to prove or disprove our concerns.
Any help from those who understand thermodynamics and can forsee topics we should look into, particularly heat transfer in biological systems, would be greatly appreciated! While a ready-made perfect reference paper trail would be great, just knowing the topics to look into on our own initiative would be really helpful. Thank you very much, I appreciate it!
Relevant answer
Answer
Dear Shane and dear all
From e purely thermodynamic point of view skin buns and burns oft he sub-lying tissue is a heat transport „problem“. One might start the discussion with Pennes’ bio heat equation (1948) which is in fact the ordinary equation for heat transport as used in engineering thermodynamics. The direction of heat transport from the inner tissue to the surface of the skin, or in the case of burns, from the skin surface towards the inner tissue is mainly perpendicular to the surface. Thus, a one dimensional solution of the heat transport equation will be fair for most problems.
Though modern thermodynamics is discussed relaying exclusively on SI units (System International: i.e. Joules for all energy instead of calories, and so forth), the “old-fashioned” units as calories etc. can be applied to all basic assumptions as well as the equations for heat transport, if required or wanted.
 Numerical solving these equations and yet calculating with “real” numbers is pretty easy as long as all boundary are well defined and are not too far from normal values (ca 36°C). Thermal properties of tissue, and in particular human tissue are known and documented [1,2]. Density and heat capacity are not mystic at all, but well established. The properties are dependent on the type of tissue and on the water content rather than on temperature.
As the “material” is not solid and in general not isotropic, transport properties are a little more complex. Thus, the first question to be answered is whether heat transport in the tissue is purely conduction as in ordinary solids or whether there is convective heat transport due to motion (diffusion) of blood or secretion (tissue fluids). And, in the case of sun light and / or radiation, one should assess the amount of radiative heat transport.
Difficulties start when exceeding a certain temperature domain. Towards low temperature one has to face reduced circulation. Finally, all convective heat transport will come to rest, and pure conduction takes place. Around 0°C real freezing will occurs. In contrast to pure water, biological fluids are mixtures and freezing or melting processes are pretty complex, and subsequent latent heats are - to my knowledge - barely investigated.
Investigating burns, serious problems will rise at elevated temperatures. Starting around 40°C, the tissue will change from healthy to burn depending on temperature and time of exposition. Approaching 100°C, bodily fluids will start to vaporise. Rising steam pressure might mechanically demolish cells and vessels. Vaporising will “bind” latent heat and heavily change the thermodynamic properties of the tissue. As the vapour tends to fly up, it will fly up and take heat apart which will be released wherever the vapour fell down and condensates.
Therefore, investigations are limited to the 0 to 100°C temperature range. As nearly no mathematics is needed, authors chose finite element methods to solve the heat transfer equation, refer to [3,4].
Shane, if you can give us some more details of your problem, I can perhaps give you some more specific advices.
[1]  A literature review on tissue properties  (If interested, I can deliver my personal investigation from 2013, not published) 
[2]  R.L. McIntosh, V. Anderson: A Comprehensive Tissue Properties Database Provided for the Thermal Assessment of a Human at Rest. doi:10.1142/S1793048010001184
[3]  A. Baldwin, J. Xu, D. Attinger:  How to Cool a Burn: A Heat Transfer Point of View.  doi: 10.1097/BCR.0b013e3182331cfe 
[4]  H. Wang, Q.H. Qin:  A Fundamental Solution-Based Finite Element Model for Analyzing Multi-Layer Skin Burn Injury.  doi:10.1142/S0219519412500273  
Best regards  
Nikolaus  
  • asked a question related to Thermal Biology
Question
1 answer
The calculation mentioned in Kenney & Zeman (2002) but not detailed. Likewise, we are interested in the testing method others use to assess Emax prior to a heat tolerance or metabolic heat production test.
Relevant answer
Answer
American Physiological Society produced a paper entitled Expanded prediction equations of human sweat loss and water needs that might be of assistance.
  • asked a question related to Thermal Biology
Question
9 answers
How would we count how much energy radiated by heat of bull/cow?
Relevant answer
Answer
emissivity for a cow 0.98   off the 1000 + measurements on large animals 450-550 Wm-2 is the range of longwave heat loss from a species in summer conditions with summer insulation 0.2 - 0.05 °Cm2W-1
  • asked a question related to Thermal Biology
Question
1 answer
Can you point to references discussing measurements of changes in emissivity of pure liquids or gases or solids, or mixtures under different conditions that also address general mechanisms behind changes in emissivity?
For instance: has anyone attempted FLIR thermography during constant temperature phase transitions, during various speeds and types of flow (turbulent, laminar in vapor or liquid or triple point state), upon exposure to DC or AC EM fields, upon introduction of varying concentration of solutes (e.g. salts, lipids above and below CMC etc.)
Studies of emissivity of materials under varying conditions seem to be mostly empirical, concentrating on wavelength, temperature, chemical composition and surface roughness effects for thermography apps.
Has the emissivity of cell cultures at constant temperature and constant number of cells been studied?
Does the emissivity change as a result of conformational changes (e.g. can protein (mis)folding be tracked in solution, can you tell density of DNA in chromosomes by thermography?
Are there FLIR microscopes?
What's your insight on emissivity via FLIR thermography versus FTIR, Raman and the rest of the spectroscopies?
Relevant answer
Answer
You can get the similar or apropriate answer by searching the keyword in the GOOGLE SCHOLAR page. Usually you will get the first paper similar to your keyword.
From my experience, this way will help you a lot. If you still have a problem, do not hasitate to let me know.
Kind regards, Dr ZOL BAHRI - Universiti Malaysia Perlis, MALAYSIA
  • asked a question related to Thermal Biology
Question
6 answers
This would be used inside large metal containers during live fire drills, underneath standard fire service equipment. We have used some methods but are interested to know if people can recommend any specific devices.
Relevant answer
Answer
Working on thermoregulation process, I have also have identified the lack of simple solution to ensure the continuous monitoring of the core temperature during our experimentations. Given the limitations of the existing devices, I decided to create my own product (e-Celsius) for temperature measurement responding to our regular technical needs.
The device is based on an ingestible capsule which collect and transmit the core temperature data to a dedicated monitor. The main advantage of our solution is the implementation of an internal memory in the pill (capacity  2000 data) which allow to continuously monitor core temperature without the monitor during around 15h. The data stored in the pill are automatically recovered when this one is replaced in the range of communication.
For more information, I would ask you to visit our website www.bodycap-medical.com and/or http://www.animals-monitoring.com/fr/ (version dedicated to animal monitoring). Also, I remain at your entire disposal for any complementary informations.
Best regards
  • asked a question related to Thermal Biology
Question
11 answers
Actually, I need this thermal cycler device in my lab. But the faculty budget for the devices this year and the next year is finished. Some colleagues advised me to search for other universities that have several used devices to give one to my faculty as a gift from university to a university
Relevant answer
Answer
Might be worth it to check out this web site of equipment donation program:
  • asked a question related to Thermal Biology
Question
1 answer
There are several industrial and reactor installations which discharge higher temperature along with their effluent when compared with the surrounding temperature levels; I would like to know the measures to reduce the same?
Relevant answer
Answer
Depending on the value of the heat, the installation could use an exchanger to recover thermal energy from the dischage and utlize it in the facility either for pre-heating processes or district heat to the facility proper, or nearby buildings. Alternatively, providing electricity is possible for a small thermal gradient as in Ocean Thermal or Japan's process heat recovery work, if a lower boiling point working fluid is used (ammonia, isobutane, or isopentane or ammonia-water). See Japanese example link or Hawaiian Ocean Thermal Link (OTECI).
Geothermal cooling and pre-mixing with nonpotable water are other alternatives that may or may not be feasible in the area, but can precool the effluent through dilution of heat. Depending on the volume of discharge, difference in temperature, and area available, a precooling retention pond structure may be built to allow themal energy to dissipate during the detention period. 
There are many ways to dissipate the energy that is really dependent on local conditions, restrictions and regulation of effluent, and temperature differences. Sometimes even doing local remdiation work on streams/rivers/lakes to improve the temperature may be adequate to offset the themal input.
  • asked a question related to Thermal Biology
Question
5 answers
They have different tertiary structures. What make it precisely the same? And which subject does this question belonged to? Hoping someone can add some proper topics!
Relevant answer
Answer
Dear Song Gong,
I can suggest this paper:
SERRANO, SOLANGE M.T. ; MAROUN, RACHID C. . Snake venom serine proteinases: sequence homology vs. substrate specificity, a paradox to be solved. Toxicon (Oxford), v. 45, p. 1115-1132, 2005.
Best regards
  • asked a question related to Thermal Biology
Question
3 answers
Some keep activity at high temperature while some lose activity quickly at lower temperatures. How does tertiary structure control it?
My question came from an article cited below:
“Soy protein isolate was separated from the defatted soy flour, modified with various urea concentrations, and compression-molded into plastics. Differential scanning calorimetry showed that the temperatures of denaturation and the enthalpies of denaturation of the modified soy protein decreased as urea concentrations increased above 1 M. At the same urea concentration, molded plastics made from the modified soy proteins showed a similar temperature of denaturation as the modified soy protein, but a lower enthalpy of denaturation. ”——Thermal and Mechanical Properties of Plastics Molded from Urea-Modified Soy Protein Isolates
Relevant answer
Answer
To my knowledge the denaturing temperature is (at least partially) controlled by the number and coordination of intra-molecular electrostatic interaction (H-bonds, stacking effects). The tertiary structure determins which H-bonds will exist - and vice versa; it is not approbriate to distinguish cause and effect here.
  • asked a question related to Thermal Biology
Question
2 answers
The goal would be to determine (under lab conditions) differences in the reproductive success after 5-6 months of winter hibernation, of female yearlings born either early or late during the previous year.
Relevant answer
Answer
Hi Leon,
Thanks for your answer!
Those experiments are actually ongoing right now. We bred them by randomizing at most, and we got plently of pups. It seems so far that there are no differences in the number of pups between early and late-born females. We have to look more precisely at the pup quality and so on.
I am using the garden dormouse (Eliomys quercinus), because it reproduces quite good, have early and late reproductive events and hibernate very well in winter (including under lab conditions too!).
Regards,
Sylvain
  • asked a question related to Thermal Biology
Question
2 answers
Relevant answer
Answer
I have a recent research paper Alireza, which may be of your interest. Please see the attachment.
  • asked a question related to Thermal Biology
Question
6 answers
Not only vultures, ostriches and many other birds that live in hot habitats also have dark feathers. Considering their extremely hot habitat and there are not many objects with such a dark color, why do they have black feathers?
Black colors can absorb sunlight better than other colors so that it can increase body temperature (like in penguins). Besides that, it's hard to camouflage since black color is easily seen in their habitats, which mostly light-brown colored.
Relevant answer
Answer
This is actually a pretty old question in thermal biology. Another version of the problem is "why are beetles in the Namib desert black?" Most of the animal physiology textbooks should give substantial insight as a starting point. Withers (1992) "Comparative Animal Physiology" is my usual starting point.
Anyway, the crux of the thing is that black is a pretty good colour in both cold and hot environments, depending on the aim of the game. In the cold it's a very good colour for absorbing heat (hence basking in ectotherms is often facilitated by physiological darkening). The thing is, through, in hot conditions it's a very good colour to dump excess heat. Since black surfaces become so much warmer than the environment heat can easily transfer from the surface by convection or conduction. So the real question you're asking here is what's the evolutionary driver for the vultures in these hot environments? Are they aiming to absorb and retain heat, or are they aiming to dump it? And of course this depends on their altitude, because during high altitude soaring they probably want to retain heat, but at low altitude they probably want to dump it. Hence, for a vulture, black is probably the best colour they could be because they can play both ends off against the middle.
This is, of course, all my general speculation. If you read some general textbooks you should be able to see whether my broad understanding is correct. Also, if you read the paper attached by Dr Blount (and references therein) you'll get a more detailed understanding specific to birds, and of course the whole thing is flexible to the stressors of ecology and evolution, as suggested by Dr. Veroustraete. My caution here is that even a simple question like this often indicates complicated patterns, and that if you get trapped in to narrow a set of assumptions, such as "black is a good colour for cold environments" you can often miss powerful insights.
Anyway, I hope that helps. I've suddenly realised that this reads like a lecture, and I'm probably not qualified to give one. Cheers
Sean
  • asked a question related to Thermal Biology
Question
7 answers
I am building operative temperature models of the collared lizard (Crotaphytus collaris). I have found several estimates of % reflectance of the lizard, but I have not found much information on spray paint reflectance values. Preferably, I would find a green colored primer spray paint in the 14-18% reflectance range - but other primer colors in this range would probably work equally well.
Relevant answer
Answer
To follow up this question, I have been given access to spectrophotometry equipment on campus that will allow me to estimate %reflectance of spray paint. I will be getting estimates of 9 different primer spray paints (on copper sheets) that should overlap the reflectance range of many lizard species (and hopefully collared lizards).
If anyone ends up needing reflectance estimates of some "lizard" spray paints, just let me know. I would be happy to provide these data.
  • asked a question related to Thermal Biology
Question
16 answers
As part of my thesis I need to take thermal profile of the oral cavity. I saw many thermal imaging cameras, usually very expensive. I saw a Flir One jacket to modify a camera for thermal imaging in iPhone. Similarly, is there any method to convert a normal camera to detect emitted IR (not reflected IR)? Is there any low cost device to detect emitted IR?
Relevant answer
Answer
Any CCD detect near IR radiation, but isn't possible increase sesitivity standard CCD camera to IR for temperature measurements. Only one possibility - remove IR filter (corrector) from low cost CCD to visualize blood vessels and changes in blood microcirculation (specially if you low cost IR LED to illumination of body under investigation). It possible use liquid crystal paint for visualization of temperature fields and CCD for registration of this changes but this methods not too safely and not in practice from 1970x... Lowest way for registration of thermo profile of oral cavity - is using single point pyroelectric (TGS) detector from detector of moving (any safety system). Analog signal from this detector is inough to measure dT less than 0.1 C, but you need add optical scaner and lens (or mirror) to obtain stable result :-)
  • asked a question related to Thermal Biology
Question
16 answers
We want to know the different body temperatures in different sites in a live mouse, for example, the temperature in the brain, abdominal, dorsal subcutaneous, etc. are the sites we are interested in.
Relevant answer
Answer
Actually it makes no sense to measure temperature in different parts of the body of a small mammal like mouse. Due to the animal small size and good fur insulation the temperature is briefly equalized within the body so that body temperature field is rather uniform. Please refer to the classic studies on the matter:
1. Hart, J. S. Calorimetric determination of average body temperature of small mammals and its variation with environmental conditions. Canadian Journal of Zoology, 1951, 29(3): 224-233;
2. Morrison, P. R. & Tietz, W. J. Cooling and thermal conductivity in three small alaskan mammals. Journal of Mammology, 1957, 38(1): 78-86.
The temperature difference will be not more then several tens of degree - the same or lower then the modern equipment accuracy. Under dry conditions the greater temperature difference may be observed only at appendages like feet and tails. So, if you need temperature of those body parts that are within "body core" it is no matter where exactly the temperature probe will be positioned. By the way, the eye temperature is a good indicator and approximation of the body core temperature. You might measure eye temperature distantly using thermal vision camera; of course it is rather expensive - the cameras suitable for such studies cost about 10.000$ and more.
  • asked a question related to Thermal Biology
Question
13 answers
I want to analyze the curve that fits a thermal swimming performance experiment. I am not sure how to fit a curve to the data and how to obtain the peak. The data is not continuous because individuals were tested only to a small sample of 6 temperatures covering the whole temperature range experience by the animals in nature. Each individual was tested to all 6 temperatures, so it is supposes that this information would be included when analyze the data because they are not independent measures. Do you know of some R package or script to do that? Which method you think is the better?
Relevant answer
Answer
TableCurve2D software is most useful for tackling this issue - there is a free trial download which you can use to explore multiple curve fits and if it may work for your data. I also recommend the approach outlined in Angilletta 2006 suggested by Juan Diego (above), but you may wish to explore further curve options or explore a particular theoretical expectation in which case other software packages are sometimes needed. Obtaining AIC values for each curve and then deriving the akaike weights allows further hypothesis testing (see Angilletta, 2006).
  • asked a question related to Thermal Biology
Question
14 answers
My research has shown that naked neck hens which feed on larger corn particles have low egg shell quality, high rectal temperature and respiratory rate compared to hens that were fed smaller corn particles. Does anyone know any article that addresses this interaction?
Relevant answer
Answer
I think Increasing the particles size of corn will increase the energy use during digestion especially in gizzard, thus heat generation during digestion will be increased and thus, hens under heat stress will suffer from the surrounding (outer) heat and increasing heat production inside the body (metabolic) which increase heat production and birds needs more energy to get ride of it, dissipate it. I think you could better see this interaction if you used two strains of laying hens with different corn particles size rather than one strain. But the decrease in the shell quality in you case seems to related low Ca/P availability under heat stress and/or respiratory alkalosis