Trends Anim Vet Sci J 2010 1(1):24-27
Trends in Animal & Veterinary Sciences Journal www.academyjournals.net
Orjinal Article
Association of Somatic Cell Count with Catalase Enzyme Activity in Bovine Bucket Milk Savas ATASEVER *, Huseyin ERDEM Department of Animal Science, Faculty of Agriculture, University of Ondokuz Mayis, 55139-Kurupelit, Samsun, Turkey Received: 03.09.2010
Accepted: 13.10.2010
Published: 03.11.2010
Abstract To investigate the relationship between somatic cell count (SCC) and catalase enzyme activity (CAT) of bovine raw milk samples from Samsun province, Turkey, bucket milk samples taken from a total of 25 smallholder farms each month were analyzed by SCC and CAT throughout a year. SCC values were determined by direct microscopic method and CAT values were obtained from the observation of enzyme activity scores. All data were statistically evaluated using SPSS. While the mean was relatively high for SCC, both SCC and CAT reached to elevated thresholds especially in 4th and 8th months. A significant correlation (r=0.623) between SCC and CAT suggests that CAT may be useful for determining bovine raw milk quality. Key words: Somatic cell count, Catalase, Bovine, Milk quality, Mastitis tests, *
Corresponding Author: S. Atasever, E-mail:
[email protected], Phone: 90-362-3121919 (1363), Fax: 90- 362-4576034
INTRODUCTION Dairy cattle farming have a special importance for many countries due to its serving nutritional products. For instance, milk production in Turkey is based entirely on dairy cows. However, traditional dairy products in Turkey are generally produced in homes under unhygienic conditions in rural regions, and these products are usually marketed through informal routes (Kirazci and Javidipour 2008). As milk and milk products are important sources of nutritients, the contamination of these products is a potential risk for human health (Var and Kabak 2009). In spite of genetical studies have been conducted on improving amount of milk per cow throughout the world, quality of milk is seen a major problem for milk sector. Such that, milk may be a detrimental product for people, when efficient techniques related to hygiene, storage or control has not been performed. That’s why, a payment system on quality degree of milk basis have been applying in many countries. As a general concept that the inflammation of udder markedly increases the somatic cell count (SCC) in milk, leading to inferior processing
characteristics and reduced acceptance of dairy products because of changes in components and properties of raw milk (Sharif and Muhammad 2008). In spite of bacteriological culture is the standart method for detecting milk whether collected from healthy cows or not (Sargeant et al. 2001), some indirect reflectors such as SCC, ph, milk flow rate, enzyme levels or electricel conductivity can be used for this aim. Of these parameters, SCC is accepted as the most reliable reflector to detect milk quailty (Koivula et al. 2005). The limit for SCC of raw milk is 400x10 3 cells/ml in the EU countries for human consumption (Leth et al. 2004). Besides, there are around 70 indigenous enzymes in milk and several of these are significant in relation to quality of milk (Riener et al. 2009). Guliye et al. (2002) emphasized that high levels of enzyme activity related to quality of milk are associated with damaged udder cells and have been used as an indicator of the degree of udder inflammation. Due to SCC data will generally not reach the farmer until 2-5 days later and the method is commonly not used at the farm level (Leth et al.
A©ademy Journals 2010
Trends Anim Vet Sci J 2010 1(1):24-27
S. Atasever & H. Erdem
2004), simple and quick indirect methods are needed to confirm by investigations. Kang et al. (2002) emphasized that catalase, a constituent enzyme of most aerobic microorganisms, strongly reflects the microbial status of raw milk. It is known that the turnover of added hydrogen peroxide in raw milk is increased significantly with mastitis due to increased amounts of catalase enzyme. Although, many studies have been carried out on the associations among milk quality parameters (Sloth et al. 2003; Ogola et al. 2007), there is no sufficient report on the relation level between SCC and catalase enzyme activity of milk of dairy cows. Revealing this correlation is required as an important option in point of reliability degree of enzyme activity, during detecting milk quality. The objectives of the current study were to determine the relationship between somatic cell count and catalase enzyme activity in bucket milks in the Black Sea region, Turkey.
In testing CAT enzyme, which catalyses hydrogen peroxide to water and oxygen (Kimbrough et al. 1997), about 10 ml raw milk was put into standard tube that is included Durham tube as reserved. After squirting 1 ml H2O2, severity of free O2 occurrence with bubble formation was recorded to be: 1: CAT negative (-), 2: CAT weak (+), 3: CAT moderate (++), and 4: CAT strong (+++) (Figure 2).
MATERIAL AND METHODS A total of 300 raw milk samples were analysed. Data were obtained by randomly collecting 25 samples of bovine bucket milks of smallholder farms in Samsun province of the Black Sea region, Turkey, during July 2008 to June 2009, monthly. All samples were kept in an ice-cooled box and immediately transported to the laboratory for analyses. In SCC analysis (Figure 1), direct microscopy that is the reference method of International Dairy Federation (1995) was applied. Figure 2 Catalase activies of raw milk samples.
SCC values were transformed to log10 for normality and homogeneity of variances. The data were examined by analysis of variance (ANOVA) and means were compared by Duncan’s multiple range test. The model was as follows: yij = µ + ai + eij where; yij is observation value for SCC or CAT, µ is population mean, ai is effect of the months (i= 1, 2, 3,…, 12), e: random residual effect. In this study, distributions of logSCC and CAT values of raw milk samples in different months are presented in Table 1. As seen that, obtained means for logSCC (raw SCC mean: 1304062 ±116627) was found to be fairly higher than the legal limit of raw milk (400x103 cells per ml) in the EU countries for human consumption (Pyörälä and Taponen 2009). Moreover, relatively high SCC mean indicates to high subclinical mastitis frequency of native cows, whose raw milk samples were examined in the present study.
Figure 1 Somatic cells (four items under a standart microscope).
25
A©ademy Journals 2010
Trends Anim Vet Sci J 2010 1(1):24-27
S. Atasever & H. Erdem SCC means (x105) (cells/ml)
Table 1 Distribution of logSCC and CAT values by months (means±SE) Month logSCC CAT 5.89±0.07abcd 2.72±0.20ab 1 5.63±0.05a 1.76±0.15a 2 ab 5.68±0.03 2.04 ±0.18ab 3 de 6.20±0.10 3.00±0.20b 4 5.73±0.05abc 2.32 ±0.21ab 5 abcd 5.95±0.05 2.80±0.20 ab 6 6.02±0.07cd 2.16 ±0.14ab 7 e 6.36±0.09 2.96±0.25b 8 bcd 5.96±0.06 2.56 ±0.25ab 9 5.98±0.06 bcd 2.96±0.18b 10 abc 5.77±0.04 2.12±0.17 ab 11 5.72±0.05 abc 2.36±0.25 ab 12 5.91±0.02 2.48±0.06 General
25 20 15
10 5 0
1
Different superscript letters in the same column indicate statistically significant differences (P
