# Presentation: 438038

## Performance of dairy cattle clones and evaluation of their milk composition

**H. Duane Norman*********,1**** and Marie K. Walsh****2**
**1****Animal Improvement Programs Laboratory**
**  ****Agricultural Research Service, USDA**
**  ****Beltsville, MD 20705-2350, USA**
**2****Utah State University, Logan, UT 84322, USA**
*******dnorman@aipl.arsusda.gov**** ******** 301-504-8334****  **

**Photo courtesy Infigen**

## Cloning biotechnology

**Embryo splitting **
**Nuclear transfer**
**Embryo**
**Somatic cell**
**Fetal**
**Adult**

## Normal performance?

**Animal health (developmental issues)**
**Mitochondrial DNA differences**
**Genotype identification (bloodtyping)**
**Genetic merit**
**Food safety**

## 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.**

## U.S. Holstein clone population

## Pedigree merit

**Mean genetic merit of parents**
**Mean genetic superiority ****(*****p*********0.01)**** of parents relative to population for same birth year:**

|  |  | Embryo split |  |  | Nuclear transfer |  |
| --- | --- | --- | --- | --- | --- | --- |
| Trait |  | Females | Males |  | Females | Males |
| Milk (kg) |  | 	186 | 	254 |  | 	165 | 	246 |
| Fat (kg) |  | 	9 | 	11 |  | 	10 | 	10 |
| Protein (kg) |  | 	7 | 	9 |  | 	8 | 	9	 |

## Genetic merit  (PTA) – cows

|  | Embryo split |  |  | Nuclear 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 | 0.02 |
| Protein (kg) | 0 | 1** |  | 2 | 2 |
| Protein (%) | 0.01 | 0.01 |  | 0.02 | 0.02 |
| SCS | 3.08 | 3.09 |  | 3.18 | 3.15 |
| PL (mo) | 0.1 | 0.2 |  | -0.6 | -0.4 |
| DPR (%) | 0.1 | 0.1 |  | -0.2 | -0.1 |

***  *******p*********0.01**
*********p*********0.001**

## Genetic merit  (PTA) – bulls

|  | Embryo split |  |
| --- | --- | --- |
| Trait | Clones | Full sibs |
| Milk (kg) | -86 | -78 |
| Fat (kg) | 0 | 1 |
| Fat (%) | 0.03 | 0.03 |
| Protein (kg) | -2 | -1 |
| Protein (%) | 0.01 | 0.01 |
| SCS | 3.2 | 3.1 |
| PL (mo) | -0.5 | -0.3 |
| DPR (%) | 0.0 | 0.2 |

## 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 | 3.63 |
| Protein (kg) | 320 | 329** |  | 326 | 325 |
| Protein (%) | 2.99 | 2.99 |  | 3.11 | 3.03 |
| SCC | 3.1 | 3.1 |  | 3.6 | 3.0 |
| PL (mo) | 25.7 | 26.4 |  | 23.1 | 26.7 |

***  *******p*********0.01**
*********p*********0.001**

## Deviation from contemporaries

|  | Embryo split |  |  | Nuclear 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 |

***  *******p*********0.05**
*********p*********0.01**

## 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**

## Milk composition (Holstein)

| Component | Clones | Non-clones | Kaufmann & Hagemeister (1987) | U.S. mean (2001) |
| --- | --- | --- | --- | --- |
| Solids (%) | 	12.9 | 	13.3 | 	13.3 | ... |
| Fat (%) | 	4.0 | 	4.3 | 	4.1 | 3.8 |
| Protein (%) | 	3.2 | 	3.1 | 	3.6 | 3.0 |
| Lactose (%) | 	5.0 | 	5.0 | 	5.0 | ... |

## 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

**No obvious differences between cloned and non-cloned cows**
**Performance**
**Milk produced**
**No food safety concerns related to milk from cloned cows**

**Conclusions**

## “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.”	

**“****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 of**
***Animal Cloning: A Risk Assessment***** ****(2003)**