Effects of Straw Particle Size and Physical Forms of Corn in Starter Diets on Growth Performance and Rumen Parameters in Holstein Calves During the Pre-Weaning Period

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Kara Ç., Çevik S., Orman A., Karslıoğlu Kara N., Berge A. C.

ANIMALS, cilt.16, sa.4, ss.1-19, 2026 (SCI-Expanded, Scopus)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 16 Sayı: 4
  • Basım Tarihi: 2026
  • Doi Numarası: 10.3390/ani16040643
  • Dergi Adı: ANIMALS
  • Derginin Tarandığı İndeksler: Scopus, Science Citation Index Expanded (SCI-EXPANDED), EMBASE, Directory of Open Access Journals
  • Sayfa Sayıları: ss.1-19
  • Açık Arşiv Koleksiyonu: AVESİS Açık Erişim Koleksiyonu
  • Bursa Uludağ Üniversitesi Adresli: Evet

Özet

This study evaluated the effects of straw particle size (short or long) and corn physical

form (ground or whole) in diets on growth performance, rumen fermentation and fecal

score in calves. Sixty female newborn calves were randomly assigned to one of the

four treatments: 90% pelleted starter and 10% short straw (PSS); 70% pelleted starter, 20%

whole corn and 10% short straw (PWCSS); 90% pelleted starter and 10% long straw (PLS);

70% pelleted starter, 20% whole corn and 10% long straw (PWCLS). In PSS and PLS treatments,

all of the corn was within the pelleted starter. Calves were weaned at 68 days of age.

Body weight (BW), wither height and heart girth were measured at 3 and 68 days of age.

Feed intakes and fecal scores were measured daily. Rumen fluid and blood samples were

collected for rumen pH, rumen volatile fatty acid (VFA) and blood β-hydroxy butyrate

(BHB) measurements at 68 days of age. Weaning BW, average daily weight gain (ADG)

and weaning wither height were significantly lower in PLS compared to other treatments.

Weaning heart girth was significantly lower in PSS and PLS than PWCSS and PWCLS.

Feed intake was significantly higher for PWCSS than PWCLS. PWCLS had a significantly

lower feed efficiency (starter feed intake/ADG) than PLS. No significant differences were

observed for ruminal pH, ruminal acetate and blood BHB among the treatments. In the diets including short straw, ruminal propionate, butyrate and total VFA concentrations

were significantly higher for PWCSS than PSS. In the diets including long straw, the ruminal

propionate concentration was significantly greater for PLS than PWCLS, and ruminal

butyrate and total VFA concentrations were not different for PLS and PWCLS. This study

indicated that the effect of corn physical form (ground or whole) on ruminal propionate,

butyrate and total VFA concentrations could vary depending on straw particle size. Fecal

score was significantly lower in PSS compared to other treatments. In conclusion, long

straw combined with pelleted concentrate reduced growth performance in pre-weaning

calves. Whole corn inclusion in the diets with long straw increased ADG and weaning BW

and improved feed efficiency.