Climate Smart Naked Neck Egg Layer Chicken Breeding Project in Palawan, Philippines

[Pinoy Angelfish]

Under free range conditions and without any use of medication, if F2 ( produced from F1 backcross to production type egg layer) chicks undergo survival of the fittest, those that survive, can we assume that they inherited, carry the genetics adapted to their tropical climate and environment- having traits for heat resistance, disease resistance, etc?

 

[Pinoy Angelfish]

That's a good point, the F1 back to the native chicken would increase egg production on native chickens. You can take the same F1 rooster and cross it to both Native and Production type egg layers, the Back Cross to any of those will surely produce better egg layers than the natives

because of natural selection i'm assuming that the mitochondrial DNA of the native naked neck hen would have less deleterious mutations if any compared to those of production type layer or heritage hens so If i want to pass on the mtDNA of the mother native naked neck hen to future generations, then it should be the F1, F2, F3, F4 daughters that need to be used for breeding, back crossing to roosters of heritage or production type egg layer breeds right?

In terms of the egg laying traits which has more influence the rooster or the hen? with the hen though, it is simple and easy to determine her laying ability, the number and size of eggs, the time interval between laying, can be observed.

 

[Pinoy Angelfish]

Review 2023
The Naked Neck Gene in the Domestic Chicken:A Genetic Strategy to Mitigate the Impact of Heat Stress in Poultry Production—A Review
Elisabete Fernandes * , Anabela Raymundo , Luisa Louro Martins, Madalena Lordeloand André M. de Almeida *

LEAF—Linking Landscape, Environment, Agriculture and Food Research Center, Associated Laboratory TERRA,Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal* Correspondence: [email protected] (E.F.); [email protected] (A.M.d.A.)

Simple Summary: Temperature and humidity are environmental factors with significant impact on animals. This challenge is not exclusive to tropical countries, as climate change has a worldwide impact. Birds are particularly sensitive to environmental changes, and high temperature causes significant financial losses. Several strategies can be used to mitigate the impact of heat stress in poultry. The use of strains tolerant to high temperature may be an interesting solution. In this review,we address the major effects of heat stress in poultry and how the naked neck gene can be used to mitigate such adverse effects.

Abstract: The poultry sector is one of the most important food industries in the world. Poultry production generates high-value protein products (meat and eggs) that are produced efficiently without the need for large areas. In poultry production, especially in the tropics, environmental factors,such as temperature and humidity, play a major role. Heat stress (HS) causes behavioral, physical,and physiological changes in poultry, with severe financial impacts. Therefore, it is important to find strategies to minimize it. The naked neck (Na) is an autosomal, incompletely dominant gene.Compared with normal feathered birds, these animals are known for their ability to adapt, perform,and reproduce under hot and humid climate conditions. Due to the absence of feathers on the neck,these animals increase heat dissipation, alleviating adverse heat effects, especially on productive performance. Genetic improvement of heat tolerance may provide a low-cost solution, of particular interest for developing countries in the tropics. The focus of this review is to evaluate the impact of HS in poultry with a special emphasis on the advantages of using the Na gene.

Copyright: © 2023 by the authors.Licensee MDPI, Basel, Switzerland.This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license ( https://creativecommons.org/licenses/by/4.0/ ).

Read article > https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10044606/pdf/animals-13-01007.pdf
Below are my naked neck (called cobra here in the Philippines) F1 roos hatched Jan 30, 2023. Their native cobra mom has repeatedly expressed pre-laying ovulation, in all four laying cycles, to date, she has never skipped a day laying an egg. One of her 3 F1 daughters has already finished laying her first clutch of 27 eggs without skipping a day... (her mom's first clutch was 13 eggs) due to pre-laying ovulation. Another daughter, currently laying eggs, has already skipped a day after laying 3 eggs; waiting to see how many eggs she will lay in her first clutch.

 

[nicalandia]

In terms of the egg laying traits which has more influence the rooster or the hen? with the hen though, it is simple and easy to determine her laying ability, the number and size of eggs, the time interval between laying, can be observed.

Egg laying trait is a Polygenic trait. So males transfer their sex linked genes(likely 2) to their doughters. Now I calculate that the total genes involved is about 20 since the reciprocal cross difference is only 10%

 

[Pinoy Angelfish]

"Egg laying trait is a Polygenic trait. So males transfer their sex linked genes(likely 2) to their doughters. Now I calculate that the total genes involved is about 20 since the reciprocal cross difference is only 10%"

Thank you Nic, this is critically important for me to know and i'm glad this breeding project started off accordingly, with the male as the provider of the egg laying traits/genes. With 20 genes involved it would really be best /necessary to do the back crossing up to the F4; and since the genes of the father are passed on to his daughters, then i also get to keep the mtDNA from the mother with her daughters being used for the back crossing.

The male F1s will still be used for back crossing.

Many, probably most backyard farmers here in Palawan do not give medication when raising their free ranging egg/meat chickens and there are different chicken diseases that are endemic,add to this the chronic heat stress due to high temperatures and humidity, there is natural selection survival of the fittest.

Can changes in mitochondrial DNA affect health and development?​

"In some cases, inherited changes in mitochondrial DNA can cause problems with growth, development, and function of the body’s systems. These variants (also known as mutations) disrupt the mitochondria’s ability to generate energy efficiently for cells."

Read full article > https://medlineplus.gov/genetics/understanding/mutationsanddisorders/mitochondrialconditions/#:~:text=In some cases, inherited changes,generate energy efficiently for cells.

 

[Pinoy Angelfish]

Mitochondrial Adaptations to Variable Environments and Their Role in Animals’ Stress Tolerance​

Inna Sokolova
Author Notes
Integrative and Comparative Biology, Volume 58, Issue 3, September 2018, Pages 519–531, https://doi.org/10.1093/icb/icy017
Published:

26 April 2018

Mitochondria as the central hub of stress tolerance​

Read article > https://academic.oup.com/icb/article/58/3/519/4986976#121542508

 

[Pinoy Angelfish]

Experimental evidence that thermal selection has shapedthe latitudinal distribution of mitochondrial haplotypes inAustralian Drosophila melanogaster

M. Florencia Camus1,2*, Jonci N. Wolff1, Carla M. Sgrò1, and Damian K.Dowling1*1 School of Biological Sciences, Monash University, Clayton, Victoria, 3800,Australia
Department of Genetics, Evolution & Environment, University College London, LondonWC1E 6BT, UK15*
To whom correspondence should be addressed.Email: [email protected], [email protected]

Creative Commons License CC BY-NC-ND 4.0 ( https://creativecommons.org/licenses/by-nc-nd/4.0/ )

Abstract

Cellular metabolism is regulated by enzyme complexes within the mitochondrion, the function of which are sensitive to the prevailing temperature. Such thermal sensitivity, coupled with the observation that population frequencies of mitochondrial haplotypes tend to associate with latitude, altitude or climatic regions across species distributions, led to the hypothesis that thermal selection has played a role in shaping standing variation in the mitochondrial DNA (mtDNA) sequence. This hypothesis, however, remains controversial,and requires evidence that the distribution of haplotypes observed in nature corresponds with the capacity of these haplotypes to confer differences in thermal tolerance. Specifically,haplotypes predominating in tropical climates are predicted to encode increased tolerance to heat stress, but decreased tolerance to cold stress. We present direct evidence for these predictions, using mtDNA haplotypes sampled from the Australian distribution of Drosophila melanogaster. We show that the ability of flies to tolerate extreme thermal challenges is affected by sequence variation across mtDNA haplotypes, and that the thermal performance associated with each haplotype corresponds with its latitudinal prevalence. The haplotype that predominates at low (subtropical) latitudes confers greater resilience to heat stress, but lower resilience to cold stress, than haplotypes predominating at higher (temperate) latitudes. We explore molecular mechanisms that might underlie these responses, presenting evidence that the effects are in part regulated by SNPs that do not change the protein sequence. Our findings suggest that standing genetic variation in the mitochondrial genome can be shaped by thermal selection, and could therefore contribute to evolutionary adaptation under climatic stress.

Read Full Article > https://www.biorxiv.org/content/10.1101/103606v3.full

Copyright
The copyright holder for this preprint is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under a CC-BY-NC-ND 4.0 International license.

 

[Pinoy Angelfish]

OPEN ACCESS ARTICLE

Marek’s Disease Virus Infection Induced Mitochondria Changes in Chickens​

by Qin Chu 1,2, Yi Ding 2, Wentao Cai 2, Lei Liu 2, Huanmin Zhang 3, and Jiuzhou Song 2

1
Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100094, China
2
Department of Animal and Avian Sciences, University of Maryland, College Park, MD 20740, USA
3
USDA, Agriculture Research Service, Avian Disease and Oncology Laboratory, East Lansing, MI 48823, USA
*
Author to whom correspondence should be addressed.
Int. J. Mol. Sci. 2019, 20(13), 3150; https://doi.org/10.3390/ijms20133150
Received: 23 May 2019 / Revised: 24 June 2019 / Accepted: 26 June 2019 / Published: 27 June 2019
(This article belongs to the Special Issue Exploring the Genotype–Phenotype Map: Regulatory Pathways)

Abstract​

Mitochondria are crucial cellular organelles in eukaryotes and participate in many cell processes including immune response, growth development, and tumorigenesis. Marek’s disease (MD), caused by an avian alpha-herpesvirus Marek’s disease virus (MDV), is characterized with lymphomas and immunosuppression. In this research, we hypothesize that mitochondria may play roles in response to MDV infection. To test it, mitochondrial DNA (mtDNA) abundance and gene expression in immune organs were examined in two well-defined and highly inbred lines of chickens, the MD-susceptible line 72 and the MD-resistant line 63. We found that mitochondrial DNA contents decreased significantly at the transformation phase in spleen of the MD-susceptible line 72 birds in contrast to the MD-resistant line 63. The mtDNA-genes and the nucleus-genes relevant to mtDNA maintenance and transcription, however, were significantly up-regulated. Interestingly, we found that POLG2 might play a potential role that led to the imbalance of mtDNA copy number and gene expression alteration. MDV infection induced imbalance of mitochondrial contents and gene expression, demonstrating the indispensability of mitochondria in virus-induced cell transformation and subsequent lymphoma formation, such as MD development in chicken. This is the first report on relationship between virus infection and mitochondria in chicken, which provides important insights into the understanding on pathogenesis and tumorigenesis due to viral infection.

5. Conclusions​

In summary, in this study we have investigated the variability of mtDNA copy number and gene expression level in the three lymphoid organs in response to MDV challenge. We found that MDV challenge had little impact on mtDNA contents in chickens of the MD-resistant line, but the mitochondrial DNA abundance and gene expression level were obviously altered at the transformation phase, especially in spleen, in chickens of the MD-susceptible line. MDV infection significantly increased the mitochondrial gene expression in the spleen tissue of the MD-susceptible birds, albeit a significant decrease of the mtDNA copy number was observed. Meanwhile, many of the nuclear genes related to mitochondrial genome maintenance and gene expression were up-regulated except for POLG2, which was conversely up-regulated in the MD-resistant line. The data indicated that the POLG2 gene may be a potential regulator for the conflict between the mtDNA copy number and the gene expression of mitochondria in the MD-susceptible birds, directly resulting in imbalance between metabolic and cell signaling and finally the MD pathogenesis and oncogenesis. Further work is warranted to look into mtDNA replication and gene transcription as well as the mitochondria regulation mechanism in relation with MDV infection in chicken.

© 2019 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license ( https://creativecommons.org/licenses/by/4.0/ )

Read Full Article > https://www.mdpi.com/1422-0067/20/13/3150

Two different chicken lines, two different mtDNAs, one is MD-resistant while the other is MD-susceptible.

A tropical Palawan chicken will have a different mtDNA to that of a temperate chicken breed.

 

[Pinoy Angelfish]

Thank You father God Lord Jesus for answering my prayers, I know this chicken breeding project is Your will, Your plan for me, based from what has been happening, including this "revelation" of breeding based on a tropically / environmentally adapted mitochondrial DNA.

Thank You also that here in Palawan there is an Indigenous chicken breed, the Parawakan, which is the biggest chicken breed in the Philippines that i can work on to improve its heat tolerance by adding the Naked Neck gene and to improve its egg laying ability... creating the Cobra Parawakan dual purpose chicken.

In addition, cross breeding the F1 Naked Neck Parawakan hens to production type and heritage egg laying roosters then back crossing until the F4 and onwards the daughters to production/heritage rooster will lead to the creation of production type and "purebred" heritage egg layer chicken breeds that carry the naked neck trait/gene and the tropically/environmentally adapted mitochondrial DNA from the Parawakan.

This chicken breeding project will serve to address climate change, food security, animal welfare, and poverty alleviation.