**6. References**


Ghader Manafiazar, Thomas McFadden, Laki Goonewardene,

*Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Canada* 

Archer, J. A., Richardson, E. C., Herd R. M., & Arthur P. F. (1999). Potential for selection to improve efficiency of feed use in beef cattle: A review. *Aust. J. Agric. Res*. 50:147-161. Basarab, J.A., Price M.A., Aalhus J. L., Okine E. K., Snelling W. M., & Lyle K. L. (2003). Residual feed intake and body composition in young growing cattle. *Can.J. Anim. Sci.*

Bewley, J. M., & Schutz M. M. (2008). Review: An Interdisciplinary Review of Body Condition Scoring for Dairy Cattle. *The professional animal scientist.* 24:507-529. Bordas, A., Tixier-Boichard M., & Mérat P. (1992). Direct and correlated responses to divergent selection for residual food intake in Rhode Island Red laying hens. *Br. Poult.* 

Capper, J. L., Roger A., & Bauman D. L. (2011). The relationship between cow production and environment impact. *WCDS Advances in dairy technology*, Vol 23: 167-179.

unknown processes (Herd & Arthur, 2009).

**5. Conclusion** 

reproduction and health.

Erasmus Okine and Zhiquan Wang

**Author details** 

**6. References** 

83: 189-204.

*Sci.* 33:741–754.

% of the variation in RFI, respectively, and the remaining variation was attributed to other

It can be concluded that there is an optimum point for the factors (DMI, milk production, body weight, AFC and environment factors) that influence the energy efficiency, and their relationship with energy efficiency is not linear. Hence, increasing output traits does not necessarily increase net energy efficiency. Therefore, the measures of energy efficiency that represent net efficiency, like RFI, which is independent from maintenance and production, need to be considered to improve efficiency in dairy cattle. It is proven that RFI is a robust measure of the animals' energy efficiency because it is independent from animals' maintenance requirements and level of production. Genetic improvement on energy efficiency can be achieved through selection for RFI in the dairy industry since the heritability estimates for RFI are moderate for most species (h2 = 0.25). Also, the traits are correlated and there are inconsistent results between species for indirect response of selection for energy efficiency on other related traits especially reproduction and health traits. Care should be taken when animals are selected for energy efficiency. Further research is required to define RFI in dairy cattle and to determine the indirect effects that selecting for efficiency may exert on other related traits, especially those related to

	- Koch, R. M., Swiger L. A., Chambers D., & Gregory K. E. (1963). Efficiency of feed use in beef cattle. *J. Anim. Sci.* 22:486-494.
	- Koots, K. R., Gibson, J. P., Smith, C., & Wilton, J. P. (1994). Analyses of published genetic parameter estimates for beef production traits. *Animal Breeding Abstracts*. 62: 309–338.
	- Korver, S., Van Eekelen E.A. M., Vos H., Nieuwhof G. J., & Van Arendonk J. A. M. (1991). Genetic parameters for feed intake and feed efficiency in growing dairy heifers. *Livest. Prod. Sci.* 29:49-59.
	- LeBlanc, S. (2010). Does higher production imply worse reproduction? *WCDS Advances in Dairy Technology,* Volume 22: 253-263
	- Lee, A. J., Boichard P. D. A., Mcauister A. J., Lin C. Y., Nadarajah K., Batraf T. R., Royis, G. L. & Veselys J. A. (1992). Genetics of growth, feed intake, and milk yield in holstein cattle. *J Dairy Sci*. 75:3145-3154.
	- Linn, J. (2006). Feed efficiency: its economic impact in lactating cows. *WCDS Advances in Dairy Technology*. Vol 18:19-28.
	- Luiting, P., & Urff E. M. (1991). Residual feed consumption in laying hens. 2. Genetic variation and correlations. *Poult. Sci.* 70:1663–1672.
	- Luiting, P., Van der Werf, J. H. J., & Meuwissen, T. H. E. (1992). Proof of equivalence of selection indices containing traits adjusted for each other. *Proceeding of the 34rd annual meeting of Euroean association of Animal production. Madrid, Spain.*
	- Meyer, M.J., Everett, R.W,. & Van Amburgh M.E. (2004). Reduced Age at First Calving: Effects on Lifetime Production, Longevity, and Profitability. *Arizona Dairy Production Conference*.
	- Moe, P. W. (1981). Energy metabolism of dairy cattle. *J. Dairy Sci.* 64:1120–1139.
	- Moore, K. L., Johnston D. J., Graser H. U., & R. M. Herd. (2005). Genetic and phenotypic relationships between insulin-like growth factor-i (IGF-I) and net feed intake, fat and growth traits in Angus beef cattle. *Aust. J. Exp. Agric*. 56:211–218.
	- Morisson, M., Bordas A., Petit M. M., Jayat-vignoles C., Julien R., & Minvielle F. (1997). Associated effects of divergent selection for residual feed consumption on reproduction, sperm characteristics, and mitochondria of sperm. *Poult. Sci*. 76:425–431.
	- National Research Council. (2001). Nutrient requirements of dairy cattle. *7th rev. ed. Natl. Acad. Sci., Washington, DC.*
	- Nielsen, M. K., Freking, B. A., Jones, L. D., Nelson, S. M., Vorderstrasse, T. L., & Hussey, B. A. (1997). Divergent selection for heat loss in mice: II. Correlated responses in feed intake, body mass, body composition, and number born through fifteen generations. *J Anim Sci.* 75: 1469–1476.
	- Nkrumah, J. D., J. A. Basarab, Z. Wang, C. Li, M. A. Price, E. K. Okine, D. H. Crews Jr, and S. S. Moore. 2007. Genetic and phenotypic relationships of feed intake and measures of efficiency with growth and carcass merit of beef cattle. J. Anim. Sci. 85:2711–2720
	- Ordway, R. S., Boucher S. E., Whitehouse N. L., Schwab C. G., & Sloan B. K. (2009). Effects of providing two forms of supplemental methionine to periparturient Holstein dairy cows on feed intake and lactational performance. *J. Dairy Sci.* 92: 5154-5166.
	- Ortigues, I., & Visseiche A. L. (1995). Whole-body fuel selection in ruminants: Nutrient supply and utilization by major tissues. *Proc. Nutr. Soc.* 54:235–251.

Perry, D., Ball, A.J., Thompson J.M., & Oddy, V.H. (1997). The relationship between residual feed intake and body components in animals selected for divergent growth rate. *Proceeding of the Advancement of Animal Breeding and Genetics.* 11, 384-388*.* 

136 Milk Production – An Up-to-Date Overview of Animal Nutrition, Management and Health

beef cattle. *J. Anim. Sci.* 22:486-494.

*Dairy Technology,* Volume 22: 253-263

variation and correlations. *Poult. Sci.* 70:1663–1672.

*meeting of Euroean association of Animal production. Madrid, Spain.* 

growth traits in Angus beef cattle. *Aust. J. Exp. Agric*. 56:211–218.

Moe, P. W. (1981). Energy metabolism of dairy cattle. *J. Dairy Sci.* 64:1120–1139.

sperm characteristics, and mitochondria of sperm. *Poult. Sci*. 76:425–431.

*Prod. Sci.* 29:49-59.

*Conference*.

*J Dairy Sci*. 75:3145-3154.

*Dairy Technology*. Vol 18:19-28.

*Acad. Sci., Washington, DC.* 

*Anim Sci.* 75: 1469–1476.

Koch, R. M., Swiger L. A., Chambers D., & Gregory K. E. (1963). Efficiency of feed use in

Koots, K. R., Gibson, J. P., Smith, C., & Wilton, J. P. (1994). Analyses of published genetic parameter estimates for beef production traits. *Animal Breeding Abstracts*. 62: 309–338. Korver, S., Van Eekelen E.A. M., Vos H., Nieuwhof G. J., & Van Arendonk J. A. M. (1991). Genetic parameters for feed intake and feed efficiency in growing dairy heifers. *Livest.* 

LeBlanc, S. (2010). Does higher production imply worse reproduction? *WCDS Advances in* 

Lee, A. J., Boichard P. D. A., Mcauister A. J., Lin C. Y., Nadarajah K., Batraf T. R., Royis, G. L. & Veselys J. A. (1992). Genetics of growth, feed intake, and milk yield in holstein cattle.

Linn, J. (2006). Feed efficiency: its economic impact in lactating cows. *WCDS Advances in* 

Luiting, P., & Urff E. M. (1991). Residual feed consumption in laying hens. 2. Genetic

Luiting, P., Van der Werf, J. H. J., & Meuwissen, T. H. E. (1992). Proof of equivalence of selection indices containing traits adjusted for each other. *Proceeding of the 34rd annual* 

Meyer, M.J., Everett, R.W,. & Van Amburgh M.E. (2004). Reduced Age at First Calving: Effects on Lifetime Production, Longevity, and Profitability. *Arizona Dairy Production* 

Moore, K. L., Johnston D. J., Graser H. U., & R. M. Herd. (2005). Genetic and phenotypic relationships between insulin-like growth factor-i (IGF-I) and net feed intake, fat and

Morisson, M., Bordas A., Petit M. M., Jayat-vignoles C., Julien R., & Minvielle F. (1997). Associated effects of divergent selection for residual feed consumption on reproduction,

National Research Council. (2001). Nutrient requirements of dairy cattle. *7th rev. ed. Natl.* 

Nielsen, M. K., Freking, B. A., Jones, L. D., Nelson, S. M., Vorderstrasse, T. L., & Hussey, B. A. (1997). Divergent selection for heat loss in mice: II. Correlated responses in feed intake, body mass, body composition, and number born through fifteen generations. *J* 

Nkrumah, J. D., J. A. Basarab, Z. Wang, C. Li, M. A. Price, E. K. Okine, D. H. Crews Jr, and S. S. Moore. 2007. Genetic and phenotypic relationships of feed intake and measures of

Ortigues, I., & Visseiche A. L. (1995). Whole-body fuel selection in ruminants: Nutrient

efficiency with growth and carcass merit of beef cattle. J. Anim. Sci. 85:2711–2720 Ordway, R. S., Boucher S. E., Whitehouse N. L., Schwab C. G., & Sloan B. K. (2009). Effects of providing two forms of supplemental methionine to periparturient Holstein dairy cows

on feed intake and lactational performance. *J. Dairy Sci.* 92: 5154-5166.

supply and utilization by major tissues. *Proc. Nutr. Soc.* 54:235–251.

	- Wall, E. H., & McFadden T. B. (2007). Optimal timing and duration of unilateral frequent milking during early lactation of dairy cows. *J. Dairy Sci.* 90(11):5042-5048.
	- Wang, Z., Colazo M. G., Basarab J. A., Goonewardene L. A., Ambrose D. J., Marques E., Plastow G., Miller, S.P., & Moore S. S. (2012). Impact of selection for residual feed intake on breeding soundness and reproductive performance of bulls on pasture-based multisire mating. Journal of Animal Science (in press, doi: 10.2527/jas.2011-4521
	- Wassmuth, R., Boelling D., Madsen P., Jensen J., & Andersen B. B. (2000). Genetic parameters of diseases incidence, fertility and milk yield of first parity cows and the relation to feed intake of growing bulls. *Acta Agri, Scandivica.* 50, 93-102.

**Chapter 7** 
