The effects of somatic cell count (SHS) and milk urea nitrogen (MUN) level on milk production and composition in some dairy cattle breeds

Abstract

In this study, the relationship between Somatic Cell Count (SCC) and Milk Urea Nitrogen (MUN) levels and their effects on milk composition were investigated some cows. In Red Danish, Simmental and Holstein cattles, average SCC’s were found to be 201.6±13.11x103 (Log10 SCC: 4.90±0622), 178.22±14.532 x103 (Log10 SCC: 4.90±0.567) and 305.7±94.37x103 cell ml-1 (Log10 SCC: 4.95±0.619), respectively. The average milk urea nitrogen (MUN) levels were measured as 8.07±0.221, 17.81±0.353, and 7.53±0.667 mg dl-1, respectively. Besides, 305 days milk yields were 7603.3±79.57, 8125.0±85.037 and 7995.9±216.51 kg; lactation lengths were 348.9±3.82, 380.0±14.26, 466.4±32.45 days; milk fat ratios were 3.60, 3.68 and 3.72%; milk protein ratios were 3.40, 3.55 and 3.33%; milk lactose ratios were 4.69, 4.73 and 4.67% and milk dry matter amounts were 12.41, 12.72 and 12.26% for Simmental, Red Danis and Holstein cattles, respectively. While the effect of urea classes on SCC was insignificant in the Simmental breed, it was significant (P<0.05) in the Red Danish and Holstein breeds. The effect of metabolic disease classes, however, was insignificant in the Simmental and Holstein breeds, and significant (P<0.05) in the Red Danish breed. The effect of SCC classes on MUN was found to be very significant (P<0.01) in Simmental and Red Danish breeds while it was determined as insignificant in Holstein breed andthe effect of metabolic disease classes was significant in all breeds (P<0.05). Additionally, differences between breeds were significant (P<0.05) in terms of metabolic disease such that ketosis rate was higher in Holstein breed compared to the other two breeds.

Keywords

• Dannish Red
• Holstein
• Simmental
• Somatic cell count
• Milk urea nitrogen

Bazı sütçü sığır ırklarında somatik hücre sayısı (SHS) ve süt üre nitrojen (MUN) seviyesinin süt verimi ve bileşimine etkileri

Öz

Bu araştırmada, somatik hücre sayısı (SHS) ve Süt üre nitrojeni (SÜN) seviyesinin birbirleri ile ilişkileri ve süt kompozisyonuna olan etkileri araştırılmıştır. Danimarka Kırmızısı, Simental, ve Siyah Alaca ırklarında SHS değerleri sırasıyla; 201.6±13.11x103 (Log10 SHS: 4.90±0.622), 178.22±14.532x103 (Log10 SHS: 4.90±0.567) ve 305.7±94.37x103 hücre ml-1 (Log10 SHS: 4.95±0.619); süt üre nitrojen (SÜN) değerleri sırasıyla; 8.07±0.221, 17.81±0.353 ve 7.53±0.667 mg dl-1; 305 günlük süt verimleri 7603.3±79.57, 8125.0±85.037 ve 7995.9±216.51 kg; laktasyon süresi 348.9±3.82, 380.0±14.26, , 466.4±32.45 gün; sütün yağ oranı %3.60, 3.68 ve 3.72; sütün protein oranı %3.40, 3.55 ve 3.33; sütün laktoz oranı %4.69, 4.73 ve 4.67; süt kuru madde oranı %12.41, 12.72 ve 12.26 olarak tesbit edilmiştir. SHS’na üre sınıflarının etkisi Sarı Alaca ırkında önemsiz, Danimarka Kırmızısı ve Siyah Alaca ırklarında ise önemli (P<0.05), metabolik hastalık sınıflarının etkisi Sarı Alaca ve Siyah Alaca ırkta önemsiz, Danimarka Kırmızısı ırkında ise önemli (P<0.05) bulunmuştur. SÜN değerine SHS sınıflarının etkisi Simental ve Danimarka Kırmızısı ırklarında çok önemli (P<0.01), Siyah Alaca ırkında ise önemsiz, metabolik hastalık sınıflarının etkisi tüm ırklarda önemli (P<0.05) bulunmuştur. Metabolik hastalıklar bakımından ırklar arasındaki farklar önemli (P<0.05) bulunmuştur. Siyah Alaca ırkında ketosis oranı diğer iki ırka göre daha yüksek, ketosis oranı ise daha düşük düzeyde bulunmuştur.

Anahtar Kelimeler

• Danimarka Kırmızısı
• Simental
• Siyah Alaca
• Somatik hücre sayısı
• Süt üre nitrojeni

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