Featured Research

from universities, journals, and other organizations

Happy And Passive Means More Productive Animals

Date:
August 18, 2005
Source:
Purdue University
Summary:
Breaking up families can be sad, but in a new method for selecting passive livestock animals, that's a main ingredient for better long-term productivity, according to a Purdue University geneticist. The new breeding program, designed to get the best out of the animals, is the first major advance in classical breeding in 20 years, said William Muir of the Purdue Department of Animal Sciences. By picking less aggressive individual animals from a broad range of families, the same breeding program can be used for hundreds of generations.

Purdue animal science geneticist William Muir used Japanese quail for his latest study of animal behavior. Using his new breeding approach of picking individual animals that are passive in their behavior and housing them together, breeders can achieve higher long-term productivity. (Purdue Agricultural Communication Service photo/Tom Campbell)

WEST LAFAYETTE, Ind. - Breaking up families can be sad, butin a new method for selecting passive livestock animals, that's a mainingredient for better long-term productivity, according to a PurdueUniversity geneticist.

Related Articles


The new breeding program, designed to getthe best out of the animals, is the first major advance in classicalbreeding in 20 years, said William Muir of the Purdue Department ofAnimal Sciences. By picking less aggressive individual animals from abroad range of families, the same breeding program can be used forhundreds of generations.

The new program enables breeders to haveoptimal improvement in productivity while minimizing the health risksassociated with inbreeding, he said. At the same time, the programovercomes competition among animals for resources that often means lessaggressive animals suffer from lack of nutrition and increased injury.In a group composed of both aggressive and passive animals, even thoseat the top of the pecking order are harmed from overeating, whichwastes food because their bodies can't properly utilize the nutrition.

"Genesnot only control your own behavior but also impact others," Muir said."For instance, if my genes make me more competitive and aggressive, italmost always comes at the expense of someone else. If a pig or chickenrises to the top of the ladder by stepping on the shoulders, or heads,of others, then a breeding program doesn't make progress."

Muir,who previously researched and advocated a group-selection theory toobtain a kinder, gentler bird, refines this breeding approach in astudy published in the current issue of the journal Genetics. In Muir'snew plan, individuals are chosen for their passiveness based onequations that identify whether an animal is so aggressive that it willnegatively affect its penmates' health and productivity.

In theoriginal group-selection program, families of animals that producedless aggressive animals were kept together. The unfortunate side effectis that such inbreeding can have dangerous genetic consequences,meaning the program could only be used for only a few generations.Muir's new breeding plan avoids the problems of inbreeding.

Becauseanimal well-being is an important factor in livestock breeding andbecause animals need to be housed in groups, not only can selecting forless aggressive animals increase productivity of individual animals,but also that of the group as a whole, Muir said. Muir calls this theassociative effects of genetics.

"It's important in a groupsetting that the animals' genes not have a negative effect on others,"Muir said. "If one pig is aggressive, his genes are negativelyimpacting 16 pigs. So, if we select pigs or other animals that getalong together, then we can have animals that grow well."

Ingroups with aggressive animals that overeat, productivity of all theanimals tends to decrease because the animals that eat more thanrequired use the food less efficiently, meaning they waste food andenergy.

"In terms of energy, you can waste energy by maintaininga pecking order," Muir said. "But if animals don't care about a peckingorder and they get along, that energy is transferred to production. So,it's a winning situation."

Muir has worked with pig breeders toestablish this type of selective program but used Japanese quail in thecurrent study to validate the practice. He chose the birds because theytend to be very aggressive, even cannibalistic. In addition, they werea good study model because they reach maturity in about six weeks, areeasily tagged and bred so pedigrees can be maintained, and it takeslittle room and feed to breed and raise them.

While beak trimmingis used in some poultry breeding programs to minimize birds injuringeach other, Muir's birds weren't beak trimmed so that their naturalbehavior could be observed.

"In my quail experiment, we havedefinite data and facts showing how the birds react in different sizegroups," Muir said. "We could assess how much negative impactaggressive birds were having on other birds.

"Aggressive birdswere causing a weight decrease in the other birds by 25 percentcompared with birds housed in non-aggressive groups."

Muir foundthat in just two generations of picking more passive quail, the flockshad a dramatic decrease in aggressive behavior and injuries. The studyalso showed that when classical breeding approaches were used,competition became worse and productivity declined, he said. The onlyway to solve this problem is through accounting for competition in thebreeding program, as the new method does.

This breeding programis easy to implement, requiring only that computer programs be used todefine competitors and set up breeding and growth groups, Muir said.

"Thiswill enhance production traits that are influenced by associativeeffects while also improving animal well-being, which leads to asuccessful situation for producers, consumers and animals," he said.

The old adage that athletes are born and not made may be even truer of animals.

"Ifyou're born with really, really passive genes, it will be hard for youto become nasty and aggressive," Muir said. "Animals don't have theability to see into the future and decide that 'if I'm reallyaggressive, I can get ahead.'"

Muir's study also examines geneticbenefits that can be obtained by using the theory to track productivityin plants. This is evident when documenting the performance of treeswhere larger trees and certain types of trees have competitiveadvantage for nutrients and sunlight.

"Researchers recognizedthis in tree breeding even before plant breeding," Muir said. "Theyhave often seen it when they thinned a stand of trees, it had muchbetter yields. The key to making this system work for increasedproductivity is tracking the pedigree of plants and animals to knowwhich ones are most likely to be passive."

Muir also is director of the Molecular Evolutionary Genetics Graduate Training Program.


Story Source:

The above story is based on materials provided by Purdue University. Note: Materials may be edited for content and length.


Cite This Page:

Purdue University. "Happy And Passive Means More Productive Animals." ScienceDaily. ScienceDaily, 18 August 2005. <www.sciencedaily.com/releases/2005/08/050804124944.htm>.
Purdue University. (2005, August 18). Happy And Passive Means More Productive Animals. ScienceDaily. Retrieved October 24, 2014 from www.sciencedaily.com/releases/2005/08/050804124944.htm
Purdue University. "Happy And Passive Means More Productive Animals." ScienceDaily. www.sciencedaily.com/releases/2005/08/050804124944.htm (accessed October 24, 2014).

Share This



More Plants & Animals News

Friday, October 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Reuters - Innovations Video Online (Oct. 24, 2014) Miniature deep sea animals discovered off the Australian coast almost three decades ago are puzzling scientists, who say the organisms have proved impossible to categorise. Academics at the Natural History of Denmark have appealed to the world scientific community for help, saying that further information on Dendrogramma enigmatica and Dendrogramma discoides could answer key evolutionary questions. Jim Drury has more. Video provided by Reuters
Powered by NewsLook.com
Black Bear Cub Goes Sunday Shopping

Black Bear Cub Goes Sunday Shopping

Reuters - Light News Video Online (Oct. 23, 2014) Price check on honey? Bear cub startles Oregon drugstore shoppers. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Dances With Wolves in China's Wild West

Dances With Wolves in China's Wild West

AFP (Oct. 23, 2014) One man is on a mission to boost the population of wolves in China's violence-wracked far west. The animal - symbol of the Uighur minority there - is under threat with a massive human resettlement program in the region. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
Breakfast Debate: To Eat Or Not To Eat?

Breakfast Debate: To Eat Or Not To Eat?

Newsy (Oct. 23, 2014) Conflicting studies published in the same week re-ignited the debate over whether we should be eating breakfast. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins