THIS PPT GIVES AN IDEA ABOUT CHICKEN AS AN EXPERIMENATION MODEL

1. EXPERIMENTATION ANIMALS
• Payaam Vohra
• Mrunmay Joshi
• Akanksha Kale
• Nangshan
{Pharmacology and Toxicology}
‘CHICKEN’
AS AN EXPERIMENTATION ANIMAL

2. Introduction
1. In the current presentation variety of intervention studies in the experimental chicken model is
discussed together with trends for the future.
2. Selection of appropriate animal models is essential to the advancement of basic and clinical
research.
3. The chicken is currently the only animal model available to probe the etiology and progression
of human ovarian cancer as well as to test chemotherapy agents. Finally the chicken is an ideal
model for toxicology studies because of its sensitivity and rapid response to environmental
toxicants and expression of external indicators, e.g., number of eggs laid, thickness of shell, as
a mark of toxic exposure.
4. Fertilized chicken eggs also act as an alternative model to address drug
distribution management of a number of diseases

3. Review of Literature
Ignacio Ayala de la Peña et al. : Atherosclerosis, a complex cardiovascular disease,
remains a global health concern. To better understand its mechanisms and develop novel
treatments, various animal models have been employed in research. This review explores
the unique role of chickens as experimental models in atherosclerosis studies. Chickens,
despite being less common than rodents or rabbits in atherosclerosis research, offer
distinct advantages. Their avian physiology shares similarities with mammals in lipid
metabolism and vascular biology, making them a valuable model organism.
Denis Zosen et al. : In this study, the authors used fertilized chicken eggs as an
alternative model to address drug distribution to the developing brain of two antiepileptic
drugs, valproic acid (VPA) and lamotrigine(LTG) at two developmental stages. VPA or
LTG was injected into the allantois of the egg on embryonic day 13.

4. Whole chicken brains were harvested at time-points of 5 min to 24 h and the
concentrations of the drugs determined using different analytical techniques. The
results of these showed distinct absorption and elimination phases and VPA or LTG
were found in the brain as early as 5–15 min after injection. Both drugs reached the
brain in clinically relevant concentrations. The study concluded that chicken embryo
model may be a suitable alternative animal model for preclinical drug distribution
studies.
Xiaohong Huang et al. : The maternal–fetal microbe transfer during gestation,
natural labor, and breast-feeding constitutes the initial gut microbiome in the
progeny, which is inevitable in the most widely utilized rodent models. The social
predisposition in precocial birds, including chickens, provides the possibility to test
behavioral responses shortly after being hatched. Hence, chickens are advantageous
in investigating the ontogenetic origin of behaviors.

5. Diseases in which it is used
Atherosclerosis
Anti-Inflammatory activity
Neuropsychiatric Disorders
Human Ovarian cancer
Epilepsy

6. Diseases in which it is used
1. Chicken is a good animal model for the study of
atherosclerosis research, since it presents lipoprotein levels
similar to those in humans.
2. Chicken embryos can be used as an alternative to the rodent
models in assessing the foetal exposure effect on
neurogenesis and investigating the mechanism underlying
the ontogenetic origin of neuropsychiatric disorders.
3. Fertilized chicken eggs are used as a model to assess drug
distribution to the developing brain of some antiepileptic
drugs like valproic acid & lamotrigine.
4. Chicken embryo and foetus have features that make the
chicken a convenient animal model for nonclinical safety
studies in which effects on different organ systems can be
tested.

7. Advantages and Disadvantages
1. The advantages of CE are largely reported in comparison with traditional mammal models,
such as its availability and reduced maturation time. Taking into account the rapid CE
development stage, drug absorption, distribution, metabolism and excretion, specifically
related to the route of inoculation and drug testing, must be deeply explore
2. It has rich vascularity and the rapid speed of tumour growth in the CAM assay
3. The developing chicken is inexpensive, accessible, and nutritionally self-sufficient with a
short incubation time and is ideal for drug-screening purposes.
4. They possess a self-contained development, uniform genetic background, robust microbiota,
and easy in vivo experimental manipulation compared to humans and rodents

8. Handling
• PSS - Tyrode solution , Carrageenan solution.
• Organ - intestine of healthy cock.
• Temperature - 34±1 degree C.
• Time - 5 mins to 24 hr.

9. Material & Methods
Egg -
For the egg of chicken, they are incubated at 37.5 degree C, humidity at 45% in an incubator.
The egg were placed in racks, mechanical tilted, mimicking the brooding of a hen.
Chicken embryo -
The CE will be considered as an animal study from the E14 stage.
Chicken -
First, we need to isolate required organ from the hen, in case of intestine the swelling is done my
by incubating with carrageenan solution, which is cleaned with a physiological buffer.

10. • It is widely used due to easy availability and maintenance.
• It’s the only model to study avian diseases.
• Important models are chick comb method, scleroderma models, autoimmune thyroiditis
etc.
• They have a S-shaped cervical region of the vertebral column
• There are two types of bones in chicken skeleton- pneumatic bone and medullary bone.
• The pneumatic bones are hollow that connects the respiratory system and hence is
adaptable towards respiration and flight.
Description of Chicken

11. • The skull and the vertebrae bones fused and form a unique structure.
• The chicken digestive system begins at the mouth and ends at the cloaca
• Soft palate and teeth are absent in chicken.
• A spherical, dark-red spleen lies on the right side of the junction between proventriculus
and gizzard.
• The U-shaped duodenal loop encloses the pancreas. The right liver lobe is larger than the
left one in chicken.
• The chicken lacks a diaphragm to inflate and deflate the lung. Instead, the chicken has
nine air sacs that distribute from the neck region to the body cavities.

12. • CE develops within 21 days, with three stages of development
• Development-: 0-8 days, with the formation of the first blood vessels at 23-24 IH
(incubation hour), and first heart beat at 33-38 IH, the circulation is well defined at 51-56
IH.
• At 7 day, the central tissue are formed, at 7-10 EID, the main organs are formed.
• 12-14 EID the tissues undergo considerable maturation, the BBB has reduced permeability
of the vascular walls of neural vessels from 14 EID.
• The immune system has an active immune response at approx. 15 EID. (Embryonic days)
• 12-18 EID, the kidney increase filtration capacity. At 16 EID, the CE has a functional liver
and competent blood clotting system.
The Development of Chicken Embryo

13. Diagrammatic Development of Chicken Embryo

14. Discussion
Tested sample was injected into the
allantois of the egg on embryonic day 13
(E13) or E16.
↓
Whole chicken brains were harvested at
time-points of 5 min to 24 h and the
concentrations of the drugs
↓
determined using GC/MS and LC-
MS/MS, for VPA and LTG, respectively.

15. The CE is a multifaceted in vivo experimental model providing analytical data for several
approaches in drug testing. Many reports have focused on drug toxicity and efficacy
through this model, proving that CE is an excellent alternative model for such purposes.
The available works suggest that experimental planning using CE as a biological model
must focus on embryonic age, route of inoculation, and adequate instrumental and drug
physicochemical properties to obtain reliable drug toxicity and efficacy data. The current
studies have revealed that chickens could offer an alternative model to rodents in the
ontogenetic origin of psychiatric disorders, including but not limited to: modeling the
disease syndrome, assessing the dosage effect and uncovering the relative paths, and
identifying novel insights for embryonic exposure altering postnatal psychosocial
exhibition. The social predisposition in precocial birds provides the possibility to test
behavioral responses shortly after hatching, which can be intervened during the pre-
hatching period.
Summary & Conclusion

16. Acknowledgement & References
1. Ayala I, Perez BG, Doménech G, Castells MT, Valdés M. Use of the chicken as an experimental animal model in atherosclerosis. Avian and
Poultry Biology Reviews. 2005 Jan 1;16(3):151-60.
2. Jijith US, Jayakumari S. Chicken intestine inflammation model for predictive in vitro screening of Anti-inflammatory activity. Research
Journal of Pharmacy and Technology. 2020;13(6):2843-8.
3. Chand N, Eyre P. Pharmacological study of chicken airway smooth muscle. Journal of Pharmacy and Pharmacology. 1978 Sep;30(1):432-5.
4. Bjørnstad S, Austdal LP, Roald B, Glover JC, Paulsen RE. Cracking the egg: potential of the developing chicken as a model system for
nonclinical safety studies of pharmaceuticals. Journal of Pharmacology and Experimental Therapeutics. 2015 Dec 1;355(3):386-96.
5. Huang X, Cheng HW. Perspective: chicken models for studying the ontogenetic origin of neuropsychiatric disorders. Biomedicines. 2022
May 17;10(5):1155.
6. Jain G, Bodakse SH, Namdev K, Rajput MS, Mishra S. Development of an ex vivo model for pharmacological experimentation on isolated
tissue preparation. Journal of Advanced Pharmaceutical Technology & Research. 2012 Jul;3(3):176.
7. Zosen D, Hadera MG, Lumor JS, Andersen JM, Paulsen RE. Chicken embryo as animal model to study drug distribution to the developing
brain. Journal of pharmacological and toxicological methods. 2021 Nov 1;112:107105.
8. Burt DW. Emergence of the chicken as a model organism: implications for agriculture and biology. Poultry science. 2007 Jul 1;86(7):1460-
71.
9. Kunz P, Schenker A, Sähr H, Lehner B, Fellenberg J. Optimization of the chicken chorioallantoic membrane assay as reliable in vivo model
for the analysis of osteosarcoma. PLoS One. 2019 Apr 15;14(4):e0215312.
10.h
We would like to express our heartfelt gratitude to Dr Ashutosh for providing us with the opportunity to explore more about chicken as an experimentation
animal