Süt Sığırlarında Topallık: Verimlilik ve Çiftlik Ekonomisine Etkileri

Yıl 2021, Cilt: 35 Sayı: 2, 451 - 466, 01.12.2021

Celal İzci Fatma Çuhadar Erdal

Öz

Modern yöntemlerin uygulandığı süt sığırcılığı işletmelerinde, yıllar içinde topallıkların yaygınlığının
artması dikkat çekicidir. Bu durum genellikle süt veriminin artmasıyla ilişkilendirilmektedir. Bu bağlamda
ortalama verim arttıkça, topallığın gelecekte daha da büyük bir sorun haline geleceği öngörülebilir. Süt
sığırlarında topallığa neden olan ayak hastalıkları enfeksiyöz ve nonenfeksiyöz olmak üzere iki kategoride
incelenebilir. Bu hastalıklar, sığırları etkileyen en önemli ağrılı hastalıklar grubundandır. Bu nedenle topallık süt sığırlarında önemli bir refah problemi olarak tanımlanır. Topallık ile süt verimi arasındaki ilişkinin
değerlendirilmesine yönelik çok sayıda çalışma yapılmıştır. Topallığa bağlı süt verimi kaybı hastalığın şiddetine, süresine, laktasyon sayısı ve dönemine ve yapılan tedaviye göre değişiklik göstermektedir. Son yıllarda dünyanın birçok ülkesinde süt sığırcılığında üreme performansının düştüğüne dair raporlar yayınlanmaktadır. Bunun önemli nedenlerinden birisinin de artan topallıklar olduğu söylenebilir. Topallığın üreme performansı üzerindeki etkilerinin nedenleri konusunda bir belirsizlik olmakla birlikte; topallığın hayvanın kızgınlık davranışı ve belirtilerini olumsuz etkilediği gösterilmiştir. Topallık hayvanın değerini düşürerek zorunlu ayıklama oranını artırır. Topal hayvanların kesime gönderilme olasılığının daha yüksek olduğu birçok çalışmada gösterilmiştir. Bu derlemenin amacı; süt sığırlarında topallıkların, verimlilik ve çiftlik ekonomisi üzerindeki olumsuz etkilerini vurgulamak ve böylece süt endüstrisinin yetiştirici, çiftlik çalışanları vb. tüm paydaşlarında topallıklar konusunda bir farkındalık oluşturmaktır.

Anahtar Kelimeler

İnek, topallık, ayıklama, ekonomi, süt verimi, üreme

Effects of Lameness on Productivity and Farm Economy in Dairy Cattle

Öz

It is noteworthy that the prevalence of lameness in modern dairy farms has increased over the years.
This situation is generally associated with increased milk yield. As the average yield increases, lameness can be predicted to become an even greater problem in the future. Foot diseases that cause lameness are commonly categorized according to their etiology into infectious and noninfectious lesions. Foot diseases are among the most important painful diseases affecting cattle. Therefore, lameness is an important animal welfare problem in dairy cattle. The relationship between lameness and milk yield has been evaluated in numerous studies. Loss of milk yield due to lameness varies according to the severity, duration of the disease, the number and period of lactation and the treatment performed. In recent years, reports of reduced reproductive performance in dairy cattle have been published in many countries. It can be said that one of the important reasons for this is increasing lameness. Although there is an uncertainty in the effects of lameness on reproductive performance; it has been shown to negatively affect the sexual behavior and symptoms of the animal. Lameness reduces fertility,
leading to early slaughter. Most studies of the relationship between lameness and early slaughter have shown that lame animals are more likely to be slaughtered. The purpose of this review is to emphasize the negative effects of lameness in dairy cattle on productivity and farm economy and to raise awareness on this issue among all stakeholders of the dairy industry, such as breeders, farm workers, etc.

Anahtar Kelimeler

Cow, lameness, culling, economy, milk yield, reproduction

Kaynakça

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