Document Type : Research Articles
1PhD student in Animal Nutrition, Faculty of Animal Sciences and Fisheries, Sari University of Agricultural Sciences and Natural Resources
Faculty member of Department of Animal Sciences, Faculty of Agricultural, Zabol University
Sari Agricultural Sciences and Natural Resources University
Introduction: Nowadays, excessive exploitation of natural resources and excessive grazing of pastures has led to a sharp decrease in feed sources for ruminant animals. Considering the fact that today most of the feed materials needed by livestock are expensive, replacing them with cheaper feed materials, in a way that does not result in a decrease in livestock productivity is of great importance. Oak fruit is one of the cheap feed that can be used in animal feed. Livestock feeding with oak fruit is particularly important due to high production per unit area, non-competition with human nutrition and easy access. The Alborz Mountains in the northern part of the country are covered by oak forests, from Talash forests to Naharkhoran forests in Gorgan, according to the climatic conditions and altitude, there are several species of oak trees. Therefore, considering the abundance of oak fruit in the forests of the central part of Mazandaran province and also the lack of scientific studies on the effects of consumption of oak fruit processed with sodium hydroxide and urea on degradability indicators and microbial protein production, the present study is to investigate the effect of different levels of oak fruit processed with sodium hydroxide and urea, fermentation parameters and rumen morphology, degradability and microbial protein production were carried out in fattening male lambs of Zel and Atabai.
Material and methods: In the first study, from the number of 20 fattening male lambs mixed with Zel and Atabai with an mean age of 5.5±0.38 months and an initial weight of 27±0.4 kg in a completely randomized design with 4 treatments and 5 repetitions for 90 The day was used. The experimental treatments included the control group (no oak fruit + polyethylene glycol) and treatments containing levels of 10, 20 and 40% in the dry matter of oak fruit processed with sodium hydroxide and urea in the diet. In the second study, the number of 3 fistulaized Zell sheep with a mean weight of about 40 kg and an average age of approximately 10 months were used to estimate the parameters of degradability. The oak fruit used in this study was randomly collected from oak trees of the Bolandmazo species (Quercus castaneifolia C. A. Mey) in different forest areas of Mazandaran province from late summer to early autumn. Data obtained were analyzed by statistical software SAS (version 1.9).
Results and discussion: The results of rumen fermentation parameters showed that there was a significant difference between experimental treatments in ammonia nitrogen, total volatile fatty acids, bacterial population and protozoa of rumen fluid (P<0.05). The treatment of 20% of processed oak fruit had the highest concentration of ammonia nitrogen and the population of bacteria and protozoa, and the treatment of 40% of processed oak fruit had the highest concentration of total volatile fatty acids in rumen fluid. There was no significant difference between the experimental treatments in the results of the morphological characteristics of the rumen villi. Degradability parameters of dry matter and crude protein were determined under the influence of experimental treatments (P<0.05). In the parameters of degradability of dry matter and crude protein, rapidly degraded fraction, constant rate of degradation and effective degradability with different passage rate had significant differences between experimental treatments (P<0.05). n the parameters of degradability of dry matter and crude protein, rapidly degraded fraction, constant rate of degradation and effective degradability with different passage rate had significant differences between experimental treatments (P<0.05). The results of gas production parameters showed that there was a significant difference between experimental treatments in gas production potential, short chain acids, digestibility of organic matter and metabolizable energy (P<0.05). The results of excretion of purine derivatives and microbial protein production showed that there was a significant difference between the experimental treatments in the amounts of excreted allantoin, xanthine+hypoxanthine, excreted purine derivatives, absorbed purine derivatives and microbial protein (P<0.05).
Conclusion: The general results of the current research showed that an increase in the concentration of volatile fatty acids, degradability of dry matter and crude protein, as well as the production of microbial protein was observed with the consumption of 40% processed oak fruit. Also, an increase in the population of ruminal fluid bacteria and protozoa was observed in the treatment of 20% processed oak fruit.