Document Type : Research Paper

Authors

• Mahboobeh Shahi ¹
• Taghi Ghoorchi ²
• Abdolhakim Toghdory ²
• Seyed Hadi Ebrahimi ³

¹ Department of Animal and Poultry Nutrition, Animal Science Faculty, Gorgan University of agricultural Science and Natural Resources, Gorgan, Iran

² Department of Animal and Poultry nutrition, Animal Science Faculty, Gorgan University of Agricultural Science and Natural Resources, Gorgan, Iran.

³ Department of Animal Science, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran

Abstract

Keywords

• fattening lambs
• cottonseed
• micronization
• sodium hydroxide
• purine derivatives
• cellulase activity

Main Subjects

• Animal Nutrition and poultry

Extended Abstract

Introduction

Cottonseed is a valuable feed ingredient due to its high fiber and energy content, which can enhance the energy and protein levels in animal diets. Micronization is a heat processing in which feeds are exposed to infrared radiation (IR) at wavelength of ≥2.5 µm within a very short period (30–90 s). Penetration of IR into the feeds increased internal temperature, resulting in protein denaturation. Denaturation reduces protein solubility and decreases ruminal protein degradability. In addition, the protein barrier reduces the digestion of starch and fat in the rumen. Sodium hydroxide treatment can affect ruminal degradability and nutrient digestibility, ultimately influencing performance. This study aimed to assess influence of feeding processed cottonseed on pH, protozoa, volatile fatty acids, rumen cellulase activity and urinary purine derivatives in fattening lambs.

Materials and Methods

   The study was conducted at the animal husbandry facility in Ghala Khan village, North Khorasan province. For this purpose, 40 Afshari male lambs (4-6 months old) with an average weight of 27.6±4 kg were randomly allocated to four treatments with ten replications for 84 days. The experimental treatments included: 1) diet containing whole cottonseed, 2) diet containing ground cottonseed, 3) diet containing micronized cottonseed, and 4) diet containing sodium hydroxide-treated cottonseed. For irradiation, 5% of drinking water was added to the cottonseed and it was rotated inside a cylinder for 10 minutes at a speed of 20 revolutions per minute until the water was completely absorbed by the seed. Then, the seeds were exposed to infrared radiation with an irradiation distance of 12 cm for 60 seconds in a gas flicker micronizer and immediately after leaving the micronizer, they were placed between two metal rollers. They were pressed and filled at a distance of 1 mm. The chemical processing of the foam samples was done in such a way that first a 4% solution of sodium hydroxide (40 grams of sodium hydroxide in 100 million liters of distilled water) was prepared. This solution was mixed with cottonseed samples to obtain 4 grams of sodium hydroxide per 100 grams of dry matter of cottonseeds, and then it was kept and dried in open air for 48 hours. Lambs were kept in individual stalls during the experiment and had free access to water during the period. Rumen content (50 ml) was filtered through muslin cloth and filtrate and particulate material (PM) were separated. To separate protozoal fraction and bacterial fraction, The filtrate was centrifuged at 450 x g at ambient temperature for 5min and the pellet was marked as P (protozoal fraction). The supernatant was centrifuged at 27000 x g at 4C for 20 min and the pellet was marked as B (bacterial fraction). The supernatant was used as a source of extracellular enzymes (EC). Further processing was same as in the case of particulate material. The clear supernatant thus collected was used as source of cellular (C) enzymes. Purine derivatives (PD) in urine including uric acid, allantoin, xanthine + hypoxanthine and estimation of microbial Nitrogen. Daily urine samples were collected in a plastic bucket containing 100 ml of 10% (vol/vol) sulphuric acid solution to reduce the ufltimate pH below 3. Every morning the total urine produced of an animal was measured individually and to prevent the precipitation (particularly of uric acid) of PD urine samples during storage. the samples collected from each sheep were pooled to give finally one pooled sample for analysis. The ruminal pH was measured immediately after sampling with a portable pH meter. Ruminal ammonia nitrogen (NH3-N) content was determined using a phenol-hypochlorite. measurment of short-chain volatile fatty acids (VFA) (acetic acid, propionic acid, butyric acid, isovaleric acid and valeric acid) were analysed.

Results

    The results of the experiment showed that cottonseed processing had no significant effect on the protozoan activity. However, cottonseed processing had a significant difference (P<0.05) on rumen pH and ammonia nitrogen. Cotton seed processing had a significant effect on acetic acid and propionic acid. No significant difference was observed in the activity of the extracellular part of carboxymethyl cellulose among the treatments. There was no significant difference in the activity of microcrystalline cellulase and carboxymethylcellulase in all sections between control and other treatments. 

Conclusions     

    These findings show that micronized cottonseed processing or addition of sodium hydroxide increased daily growth and decreased feed conversion ratio and can be recommended in the diet of fattening lambs.

Author Contributions

Conceptualization, Taghi Ghoorchi., and Abdolhakim Toghdory.,methodology, Mahboobeh Shahi and Taghi Ghoorchi software, Mahboobeh Shahi and Abdolhakim Toghdory.;validation, Taghi Ghoorchi., and Abdolhakim Toghdory.; formal analysis, Abdolhakim Toghdory.; investigation, Mehdi Mahboobeh Shahi and Taghi Ghoorchi., resources, Taghi Ghoorchi.;data curation, Taghi Ghoorchi.; writing—original draft preparation, Mahboobeh Shahi., writing—review and editing, Taghi Ghoorchi.; visualization, Taghi Ghoorchi.; supervision, Taghi Ghoorchi.; project administration, Taghi Ghoorchi.; funding acquisition, Taghi Ghoorchi. All authors have read and agreed to the published version of the manuscript

Data Availability Statement

Data available on request from the authors.

Acknowledgements

We would like to thank the Faculty of Animal Sciences, Gorgan University of Agricultural Sciences and Natural Resources, for providing the field and laboratory facilities for this research.

Ethical considerations

The study was approved by the Ethics Committee of Gorgan University of Agricultural Sciences and Natural Resources. The authors avoided data fabrication, falsification, plagiarism,and misconduct.

Conflict of interest

The author declares no conflict of interest.