بررسی ارتباط بین غلظت نشاسته دفعی از طریق مدفوع با سایر ترکیبات مدفوع در گاوهای هلشتاین اوایل دوره شیردهی

نوع مقاله : مقاله پژوهشی

نویسندگان

• ایوب محمدی ¹
• فرهنگ فاتحی ²
• کامران رضایزدی ²
• علی صادقی سفید مزگی ¹
• محمد هادی خبازان ³
• فرهاد پرنیان خواجه دیزج ⁴

¹ گروه علوم دامی، دانشکدگان کشاورزی و منابع طبیعی دانشگاه تهران، کرج، البرز، ایران

² گروه علوم دامی، دانشکدگان کشاورزی و منابع طبیعی دانشگاه تهران،کرج، البرز، ایران.

³ مدیر تولید دامپروری هلدینگ کشاورزی و دامپروری فردوس پارس، تهران، ایران

⁴ بخش تحقیقات علوم دامی، مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی آذربایجان شرقی، سازمان تحقیقات و آموزش و ترویج کشاورزی، تبریز،

چکیده

کلیدواژه‌ها

• اسیدیته مدفوع
• تابعیت چندگانه
• گاو هلشتاین پرتولید
• نشاسته مدفوع

موضوعات

• تغذیه دام و طیور

عنوان مقاله [English]

Investigation of the Relationship Between Fecal Starch Concentration and other Fecal Components in Early Lactating Holstein Cows

نویسندگان [English]

• Ayub Mohammadi ¹
• Farhang Fatehi ²
• kamran Reza-yazdi ²
• Ali Sadeghi-Sefidmazgi ¹
• Mohammad Hadi Khabazan ³
• Farhad Parnian-khajehdizaj ⁴

کلیدواژه‌ها [English]

• Fecal pH
• Fecal starch
• Holstein dairy cows
• Multivariate regression

Extended Abstract

Introduction

    Nutritional management of early lactation dairy cows is one of the most challenging aspects of dietary management in modern dairy herds. This is because these early lactating cows have the highest daily dry matter intake as a percentage of body weight, and any imbalance in the diet can lead to acidosis and digestive problems (Fredin et al., 2014). In the diet of these cows, to achieve maximum milk production, a large amount of starch from grain sources is included daily. Due to the high passage rate of feed materials in the digestive system of these cows, without proper nutritional management, a significant portion of consumed starch passes through the rumen, and after partial digestion in the small intestine, undigested amounts reach the end of the digestive tract (Owens et al., 2015; Mills et al., 2017). There, it ferments, and ultimately, a considerable portion is excreted through feces. Therefore, the objective of the present study was to investigate the relationship between fecal starch concentration and other fecal components in early lactation Holstein cows and to develop predictive models for its estimation.

Materials and Methods

    This study was conducted on 76 Holstein dairy herds, where one pen of early Holstein lactating Cows was selected as the index pen from each herd based on average milk production, days in milk, and parity. From each pen, 10 cows were selected with body condition score of 3±0.25, days in milk of 80±10, milk production of 47±2.5, and parity of 2.5±0.5. Sampling of total mixed ration, feed ingredients, and feces was conducted for three consecutive days. Finally, data such as forage-to-concentrate ratio in the diet, as well as fecal starch values and ratios, crude protein, neutral detergent fiber, and organic matter in feces were measured. It should be noted that fecal pH was measured immediately after fecal sampling. Finally, using the obtained data, fecal excreted starch was estimated using univariate and multivariate linear regression models. The prioritization criteria for the effects of each parameter was determined using the coefficient of determination.

Results and Discussion

    The descriptive results of this study showed that the mean percentages of excreted starch, fecal pH, crude protein percentage, crude protein values per day, neutral detergent fiber percentage, neutral detergent fiber values per day, and fecal organic matter in early Holstein lactating Cows herds were 11.5, 6.58, 16.9, 1.65, 46.1, 4.46, and 83.1, respectively. Based on univariate prioritization, the decrease in fecal excreted starch with increasing fecal pH, fecal protein percentage, excreted protein values per day, and fecal neutral detergent fiber was demonstrated with determination coefficients of 0.48, 0.38, 0.28, and 0.19, respectively (P-value ≤0.01). It should be noted that the correlation between fecal starch percentage and other fecal parameters including fecal pH, fecal protein percentage, excreted protein values per day, and fecal neutral detergent fiber was -0.69, -0.61, -0.53, and -0.43, respectively, indicating an inverse correlation between excreted fecal starch and these parameters. Furthermore, results of multivariate regression revealed that model  containing fecal pH, fecal protein percentage, and fecal neutral detergent fiber percentage (48.52 – 3.66 pH - 3.77 CPF + 1.11 NDFF), had the highest coefficient of determination of 0.61.

Conclusion

    The results of current study demonstrated a significant correlation between fecal excreted starch and other fecal components. Additionally, the results showed that excreted starch could be estimated with an acceptable accuracy by multivariate regression approach.

Data Availability Statement

This article contains all the data that were created or evaluated during the research.

Acknowledgements

The authors would like to sincerely thank the members of the Faculty of Animal Sciences, University of Tehran Research Council for the approval and support of this research.

Conflict of interest

The author declares no conflict of interest.