**Author details**

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

there was no consistent inuence of the age of the cows on avoidance distance.

**4.5. Body condition scoring** 

genetically and phenotypically.

**4.6. Lameness** 

to improve stock people's attitude and behavior toward dairy cattle can reduce flight distance from humans and increase milk (protein and fat) yield (Hemsworth et al., 2002). Furthermore, the attitude of the stockperson towards interacting with farm animals is an important determinant of the stockperson's behavior and thus the animal's fear of humans (Hemsworth, 2004; Waiblinger et al., 2006). The results conrm our hypothesis, that the avoidance distance validly reects the human–animal relationship. This is in line with earlier results, where avoidance distance was correlated with the behavior of the farmer (Waiblinger et al., 2002). In experimental studies, avoidance reactions of cattle were inuenced by previous experience of positive or negative handling (Munksgaard et al., 2001; Hemsworth, 2004; Waiblinger et al., 2006). The average age of the cows did not confound the assessment of human–animal relationship on the farms in our study. Also within farms,

Body condition is a subjective assessment of the amount of fat, or amount of stored energy, a cow carries. Body condition changes throughout the lactation cycle. Cows in early lactation are in negative energy balance and losing body condition (mobilizing body reserves). Our found are in agreement with those of Studer (1998) who explained that high producing cows whose body condition score declines by 0.5 to 1.0 during lactation often experience anoestrus. However, a loss of condition score of about 1.0 during lactation was normal in the review presented by Broster & Broster (1998) and Popescu et al. (2009). An ideal body condition score is 3.0. Dechow et al. (2001) found that higher body condition scores were favorably related genetically to reproductive performance during lactation. While higher body scores during lactation were moderately negatively related to milk production, both

Lameness is a crucial welfare issue in modern dairy production (Vermunt, 2007). It indicates a painful state and discomfort and is regarded as one of the most serious welfare problems in cattle. In our study, a significant percentage of dairy cattle (59) have severe lameness, this can be a sign of poor overall welfare standards within the herd. Hristov et al. (2008) noticed that lameness is indisputably the major welfare problem for the dairy cow. Our findings are in agreement with those of Webster (2005) who reported that half the cows go lame in any one year and 20% are lame at any one time. Lameness in any cow is usually a sign that they are in pain, ill-health and discomfort. It clearly affects cow welfare, as well as their performance and production (Bergsten, 2001; Ward, 2001; DEFRA, 2003; Hristov et al., 2008). Lameness in dairy cows impacts negatively on herd welfare and productivity. It is thought to be closely associated with avoidance of pain caused by limb lesions and, particularly in dairy cattle, by hoof lesions (Dyer et al 2007). It certainly stands out as a consequential and complex welfare problem in dairy cattle (Bergesten, 200; Rajkondawar et al., 2001; Ward, 2001). Leach et al. (2008) advise that a limited number of available cubicles are a high risk factor for lameness; in addition, deep bedding and soft lying surface play a key role Naceur M'hamdi\* , Saoussen Frouja and Rafik Aloulou *Département des Sciences Animales, Institut Supérieur Agronomique de Chott-Mariem, Sousse, Tunisie* 

Mahdi Bouallegue *Faculté des Sciences Mathématiques Physiques et Naturelle de Tunis, Campus Universitaire, Tunisie* 

Satinder Kaur. Brar *Institut National de la Recherche Scientifique, Québec, Canada* 

Mohamed Ben Hamouda *Institution de La Recherche et de l'Enseignement Supérieur Agricole, (IRESA), Ministère de l'Agriculture et des Ressources Hydrauliques, Tunisie* 
