2003 clone risk assessment workshop (hdn-1) performance of dairy cattle clones and evaluation of...

2003Clone risk assessment workshop (HDN-1)

Performance of dairy cattle clones and evaluation of their milk compositionH. Duane Norman*,1 and Marie K.

Walsh2

1Animal Improvement Programs Laboratory Agricultural Research Service, USDA Beltsville, MD 20705-2350, USA

2Utah State University, Logan, UT 84322, USA

*[email protected] 301-504-8334

Photo courtesy Infigen

2003

Clone risk assessment workshop (HDN-2)

Cloning biotechnology

Embryo splitting

Nuclear transfer Embryo Somatic cell

Fetal Adult

2003


Normal performance?

Animal health (developmental issues)

Mitochondrial DNA differences

Genotype identification (bloodtyping)

Genetic merit

Food safety

2003


Research studies

Norman, Lawlor, and Wright (2002). Proceedings of 7th World Congress on Genetics Applied to Livestock Production 33, 699-702.

Norman, Lawlor, and Wright (2003). Journal of Dairy Science (in press).

Walsh, Lucey, Govindasamy-Lucey, et al. (2003). Cloning and Stem Cells 5, 213-219.

2003


U.S. Holstein clone population

2003


Pedigree merit

Mean genetic merit of parents

Mean genetic superiority (p0.01) of parents relative to population for same birth year: Embryo split Nuclear

transferTrait Femal

esMale

sFemal

esMale

sMilk (kg) 186 254 165 246Fat (kg) 9 11 10 10Protein (kg)

7 9 8 9

2003


Genetic merit (PTA) – cows

Embryo splitNuclear transfer

Trait Clones

Full sibs

Clones

Full sibs

Milk (kg) -37 -1* -18 9

Fat (kg) 1 2* -3 0

Fat (%) 0.02 0.02 -0.02 0.02Protein (kg)

0 1** 2 2

Protein (%) 0.01 0.01 0.02 0.02SCS 3.08 3.09 3.18 3.15PL (mo) 0.1 0.2 -0.6 -0.4DPR (%) 0.1 0.1 -0.2 -0.1

*p0.01**p0.001

2003


Genetic merit (PTA) – bulls

Embryo splitTrait Clones Full sibsMilk (kg) -86 -78Fat (kg) 0 1Fat (%) 0.03 0.03Protein (kg) -2 -1Protein (%) 0.01 0.01SCS 3.2 3.1PL (mo) -0.5 -0.3DPR (%) 0.0 0.2

2003


Mean standardized performance

Embryo split Nuclear transfer

Trait Clones

Full sibs

Clones

Full sibs

Milk (kg) 10,716

11,016*

*

10,456

10,715

Fat (kg) 394 402* 379 389

Fat (%) 3.68 3.65 3.62 3.63Protein (kg)

320 329** 326 325

Protein (%)

2.99 2.99 3.11 3.03

SCC 3.1 3.1 3.6 3.0PL (mo) 25.7 26.4 23.1 26.7

*p0.01**p0.001

2003


Deviation from contemporaries

Embryo splitNuclear transfer

Trait Clones Full sibs

Clones Full sibs

Milk (kg) -199 3** -278 -305

Fat (kg) -2 3* -17 -13

Protein (kg)

-3 2** -2 -7 *p0.05**p0.01

2003


Milk composition

Traits analyzed: Solids, fat, fatty acid profile, lactose, protein

Nuclear-transfer clone breeds: Brown Swiss, Holstein, Holstein Jersey

No differences between clones and non-clones for gross chemical composition of milk

Slight difference for palmitic acid

Mineral content most variable component

2003


Milk composition (Holstein)

ComponentClone

sNon-

clones

Kaufmann &

Hagemeister (1987)

U.S. mean (200

1)

Solids (%) 12.9 13.3 13.3 …Fat (%) 4.0 4.3 4.1 3.8Protein (%) 3.2 3.1 3.6 3.0Lactose (%) 5.0 5.0 5.0 …

2003


U.S. dairy cattle selected for cloning slightly superior genetically to population for yield

No obvious differences between cloned and non-cloned cows Performance Milk produced

No food safety concerns related to milk from cloned cows

Conclusions

2003


“Most clones that survive the perinatal period are normal and healthy as determined by physiological measurements, behavior, and veterinary examinations.”

“Edible products from normal, healthy clones or their progeny do not appear to pose increased food consumption risks relative to comparable products from conventional animals.”

U.S. Food & Drug Administration

Draft Executive Summary ofAnimal Cloning: A Risk Assessment

(2003)

2003 clone risk assessment workshop (hdn-1) performance of dairy cattle clones and evaluation of...

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