The Effect of Disease Free Status of Dairy Cattle Farms on Colostrum Composition and Hygiene

Öz

Sustainable calf breeding requires reducing disease incidence and effectively supporting the immune system. In neonatal calves, passive immunity is achieved through the intake of an adequate quantity and quality of colostrum within the first few days after birth. The immunological richness of colostrum, as well as its provision under hygienic conditions, plays a critical role in calf survival. During the disease-free certification process, farms are evaluated based on criteria such as animal health, hygiene, milk quality, and record-keeping practices. This study investigated the effect of disease-free herd status on the composition and hygiene of colostrum. Colostrum samples were collected from a total of 24 cows in their second or later lactation periods, including 12 from certified disease-free farms and 12 from non-certified farms. The nutritional composition and microbial count (total bacteria, total coliforms, and E. coli counts) of the collected colostrum samples were analyzed. Among the measured parameters, only electrical conductivity showed a statistically significant difference between the groups; no significant differences were observed in the other parameters. No statistically significant differences were found between the groups in the parameters examined in colostrum. However, numerical increases were observed in parameters such as TKM, protein, lactose, salt, and %Brix in farms with a Disease-Free Certificate. Moreover, disease-free status resulted in statistically significant reductions in total bacteria, total coliforms, and E. coli counts. In conclusion, the disease-free status of farms did not affect the nutrient composition or immunoglobulin (Ig) content of colostrum. However, total bacterial count, total coliform bacteria, and E. coli numbers were significantly reduced by approximately 2 log in disease-free farms. Although microbial quality was better in disease-free farms compared to other farms, neither European nor U.S. standards were met. These findings highlight the importance of increasing the number of disease-free farms for improving colostrum quality and reducing microbial load, which is critical for both animal health and food safety.

Anahtar Kelimeler

• Disease-free
• Colostrum
• Nutrient content
• Microbial count

Destekleyen Kurum

This study was supported by the Scientific and Technological Research Council of Turkey (TÜBİTAK) within the scope of 2209/A.

Proje Numarası

1919B012326866

Etik Beyan

Ethics committee permission is not required for this study.

Teşekkür

This study was supported by the Scientific and Technological Research Council of Turkey (TÜBİTAK) within the scope of 2209/A.

Süt Sığırcılığı İşletmelerinin Hastalıktan Ari Olma Durumunun Kolostrum Kompozisyonu ve Hijyeni Üzerine Etkisi

Öz

Sürdürülebilir buzağı yetiştiriciliği, hastalık insidansının azaltılması ve bağışıklık sisteminin etkin biçimde desteklenmesini gerektirmektedir. Yeni doğan buzağılarda pasif bağışıklık, doğumdan sonraki ilk günlerde yeterli miktarda ve kaliteli kolostrum alımı ile sağlanmaktadır. Kolostrumun immunolojik açıdan zengin olması kadar, hijyenik koşullarda sunulması da yaşama gücü üzerinde belirleyici rol oynamaktadır. Hastalıktan arilik sertifika sürecinde işletmeler, hayvan sağlığı, hijyen, süt kalitesi ve kayıt tutma kriterlerine göre değerlendirilmektedir. Bu araştırmada, Hastalıktan Ari olma durumunun kolostrumun kompozisyonu ve hijyeni üzerine etkisi incelenmiştir. Çalışmada, Hastalıktan Arilik Belgesine sahip işletmelerden 12 adet ve belgesine sahip olmayan işletmelerden de 12 adet olmak üzere toplamda 24 adet 2 ve üzeri laktasyonda olan inekten kolostrum örnekleri toplanmıştır. Bu çalışma dahilinde toplanan kolostrumların besin içerikleri ve mikrobiyal yükü (toplam bakteri, toplam koliform bakteri ve E. coli sayısı) belirlenmiştir. Kolostrumlar da incelenen parametrelerde gruplar arasında istatistiki olarak bir farklılık tespit edilmemiştir. Ancak, Hastalıktan Arilik Sertifikası bulunan işletmelerde TKM, protein, laktoz, tuz ve %Brix gibi parametrelerde sayısal artış gözlenmiştir. Ayrıca, hastalıktan ari olma durumu toplam bakteri, toplam koliform bakteri ve E. coli sayısında istatistiki olarak önemli bir farklılık meydana getirmiştir. Sonuç olarak, Hastalıktan ari olma durumu kolostrumların besin içeriklerini ve Ig miktarını etkilememiştir. Hastalıktan ari işletmelerinde toplam bakteri, toplam koliform bakteri ve E. coli sayısında yaklaşık 2 log’lık önemli bir azalma görülmüştür. Hastalıktan ari işletmelerde mikrobiyal kalite diğer işletmelere göre daha iyi olsa da ne Avrupa ne de ABD standartlarına ulaşılamamıştır. Bu bulgular, kolostrum kalitesinin arttırılması ve mikrobiyal yükünün azaltılmasında hastalıklardan ari işletmelerin sayısının arttırılmasının önemini vurgulamaktadır; hem hayvan sağlığının korunması hem de gıda güvenliğinin sağlanması açısından büyük önem taşımaktadır.

Anahtar Kelimeler

• Hastalıktan ari
• Kolostrum
• Besin içeriği
• Mikrobiyal yük

Destekleyen Kurum

Bu çalışma 2209/A kapsamında Türkiye Bilimsel ve Teknolojik Araştırma Kurumu (TÜBİTAK) tarafından desteklenmiştir.

Proje Numarası

1919B012326866

Etik Beyan

Bu çalışma için etik kuruldan izin alınmasına gerek yoktur.

Teşekkür

Bu çalışma 2209/A kapsamında Türkiye Bilimsel ve Teknolojik Araştırma Kurumu (TÜBİTAK) tarafından desteklenmiştir.

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