Communication Relationship between blood haemoglobin and serum iron concentrations and heart girth in pre-weaned dairy calves Jožica Ježek, Jože Starič, Marija Nemec, Tomaž Zadnik, Martina Klinkon Clinic for Domestic Ruminants. University of Ljubljana, Slovenija Corresponding author: Prof. Dr. Martina Klinkon. Clinic for Domestic Ruminants, University of Ljubljana, Cesta v Mestni log 47, 1000 Ljubljana - Tel. +386 1 4779 215 - Fax +386 1 283 23 08 - Email: Martina.
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ABSTRACT - The aim of the research was to study the relation between blood haemoglobin (Hb) and serum iron (Fe) concentrations and changing of heart girth with age in calves. Blood samples of 66 dairy calves were taken at the age of 3, 5 and 16 weeks (wks). Blood samples were analysed for Hb and serum Fe concentration. At each bleeding, the heart girth was measured. The lowest mean concentration of Hb was measured at the age of five wks. The concentration of serum Fe and heart girth increased with age. Significant positive correlations were found between Fe concentration at 3 wks of age and heart girth of calves at 5wks (r=0.270; P=0.032) and between Fe concentration at 5 wks and heart girth of calves at 5 (r=0.283; P=0.021) and 16 wks (r=0.284; P=0.028). The lowest Hb concentration recorded at 5 wks, might suggest that this is the most critical period for developing anaemia in calves. The correlations established between heart girth and Fe concentration at different ages indicate that serum Fe concentration has some influence on changing of heart girth in calves. Key words: Calves, Haemoglobin, Serum iron, Heart girth. Introduction - Measuring of different blood variables is useful to asses the health status and welfare of calves. In growing calves the feeding and rearing system has an important influence on the values of haematological parameters (Reece and Hotchkiss, 1987). Like young animals of other species also the calves are prone to become anaemic due to iron deficiency. Iron is an essential component of haemoglobin, myoglobin and several enzymes. The iron reserves of the calf are generally sufficient to prevent serious anaemia if calves are fed dry feeds beginning at few weeks (wks) of age. Iron deficiency is associated with numerous clinical signs, including anaemia, reduced growth, and increased rates of disease. Different values are reported as normal Hb concentration in calves from the viewpoint of welfare (Von Borell, 1998; Council Directive 2008/119/EC). The administration of iron supplements on haematological parameters, serum iron and growth performance was investiItal.J.Anim.Sci.
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8 (Suppl. 3), 151-153, 2009
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gated in different studies (Bostedt et al., 2000; Heidarpour Bami et al., 2008). The aim of our study was to investigate the relation between blood Hb and Fe concentration and changing of heart girth with age in dairy calves. Material and methods - Sixty six dairy calves from two farms were included in the research. After calving, the calves got 1 to 1.5 liter colostrum from their mother. After 10 days of age, they had free access to dry starter (pellets) and hay. They were weaned at the age of 16 wks. In the research period, from birth to the age of 16 wks, the health status was monitored. Blood samples from the calves were taken at the age of 3, 5 and 16wks, before weaning. In blood samples the concentration of Hb was measured with haematology counter ABC Vet (ABX, France). The concentration of serum iron was measured with biochemical analyser Cobas Mira (Hoffman-LaRoche). At each bleeding the heart girth was measured on standing calf behind the fore legs, by the same person (assessor). The calves were divided into 2 groups according to their Fe concentration (cut off 20 μmol/L) and heart girth at 5 and 16 wks was compared. The data were processed with the statistical program SPSS (Ver 15) (SPSS, 2006). Descriptive statistics and Pearson correlations were performed on investigated parameters. Influence of age was assessed with ANOVA and differences between groups with Dunett T3 test. Groups regarding Fe (20 μmol/L) were compared with t-test. Results and conclusions - Age of calves influenced significantly the investigated parameters (P
