جستجوی مقالات مرتبط با کلیدواژه « molasses » در نشریات گروه « علوم دام »

Sources of protein are the most expensive part of animal feed, and every year a large amount of these sources are imported from abroad for use in animal husbandry industry. One of the important steps in reducing the cost of feed is the optimal use of available resources and the recognition of new foods and their use in animal rations. On the other hand, every year, a huge amount of agricultural product residues are obtained, which can be used in animal nutrition. Optimum use of agricultural by-products and processing industries in feeding ruminants is important from economic and environmental aspects. Pea (Pisum sativum L.) is a cool-season crop and one of the most important legumes, in the temperate climatic regions and it has been widely consumed as a legume or vegetable throughout the world for the purpose of both human nutrition and animal nutrition. Peas are cultivated with the aim of producing green seeds, but after harvesting the pods containing seeds, its waste can be used by ruminants as high-quality bulk feed. The by-product after the harvesting of chickpeas (green chickpeas) which can be extracted and separated manually is the parts of the stem, leaves and pods that are free of green seeds. This research was conducted in order to investigate the effect using organic acid (acetic acid) and fibrinolytic enzyme and molasses on chemical composition, fermentation characteristic, gas production and digestibility parameters of pea silage.

Whole crop pea silage was harvested and chopped with a conventional forage harvester under farm condition to length of 2-3 cm. Representative of pea forage sample was packed manually, in triplicate into plastic bags. The filled silos were stored at ambient temperature and allowed to ensile for 45 days. The following treatments were applied to the forage samples: 1) pea forage without any additives (control), 2) control + fibrinolytic enzyme(2 grams per kg of dry matter), 3) control + organic acid(2%), 4) control + molasses(8%) and 5) control + (fibrinolytic enzyme+ molasses). Additives diluted in deionized water and applied with a hand held sprayer while forage samples were stirred manually. A similar quantity of deionized water was sprayed on the control forage. After designated ensiling times, silos were opened and the ensiled forage was mixed thoroughly and then were dried at a 60°C in oven for 48 h and then ground to pass through a 2 mm screen for later analysis.

Results showed that there were significant differences among treatments on NDF, CP and pH (P>0.05). Enzyme treated silages had lowest NDF content (46.50%) compared with other treatments (P<0.05). The lowest pH was related to treatment containing molasses. silage treated with organic acid improved aerobic stability, significantly. There were significant differences among treatments on gas production parameters(P<0.05) and molasses and enzyme treated pea silage had highest and lowest gas production potential than others (199.1 and 183.3 ml/g DM, respectively). Results showed that there were no significant differences among treatments on DMD and partitioning factor (P>0.05). Organic acid treated silages had lowest effect on DMD and OMD compared with other treatments (P<0.05).

Overall, results showed that using molasses and molasses + enzyme as additive can be improwed nutritive value of pea silage better than others. Anyway, green pea forage according to the appropriate level of crude protein similar to corn forage and its silage characteristics, has the potential of silage and can be used in livestock feeding.

To achieve maximum microbial protein production and efficiency of feed protein utilization, the simultaneous availability of rumen degradability carbohydrate and nitrogen sources for ruminal microorganisms is essential. When using urea, due to its very high ruminal degradability rate, highly fermentable carbohydrate sources such as soluble sugars should be used to achieve maximum efficiency of nutrients utilization, microbial protein production and fermentation. On the other hand, considering the rate of nitrogen release in slow-release urea compared to urea, it seems that the type of carbohydrate source and its degradation rate should be considered when using this product in the diet of lactating cows, because it can affect the efficiency of nitrogen utilization in the rumen. Therefore, the aim of this study was to investigate the effect of carbohydrate source type on the performance of Holstein lactating cows fed a diet containing slow-release urea.

This experiment was performed in the 3 periods in a completely randomized design as repeated measurement using 9 Holstein lactating cows (average weight: 650± 50 kg, milk production: 33± 0.5 kg and DIM: 100± 25 days) in three 21-day periods. Experimental treatments were; 1. basal diet include Nitroza® (a source for slow- release urea, as control); 2. basal diet plus 2.7 % molasses as a replacement for corn grain and 3. basal diet plus 2.7% barley grain as a replacement for corn grain. To measure ruminal fermentation parameters, on the day 21 of each period, four hours after the morning meal, ruminal fluid was collected. Apparent digestibility of nutrients were measured by acid insoluble ash as internal marker. The milk production was recorded daily and on the day 20 of each period, milk produced from each animal was sampled at each meal to measure the milk composition. To determine the concentration of serum albumin, glucose, total protein, cholesterol, triglyceride and urea nitrogen concentration on day 21 of each period, 4 hours after the morning meal, blood samples were taken from the tail vein of each animal.

The results of the present study showed that the addition of molasses and or barley grain as a replacement for a part of corn grain had no significant effect on feed and nutrient intake (except for organic matter). Compared to the control group, replacing corn with molasses in a diet containing slow-release urea increased the amount of organic matter intake (P< 0.01). The results of independent comparisons showed that the addition of molasses compared with control and barley treatment reduced ADF intake, but increasing the amount of barley in the diet resulted an increase in the ADF intake (P< 0.02). Treatments had no significant effect on apparent digestibility of nutrients, ruminal fluid pH, total concentration of volatile fatty acids, molar ratio of propionate, butyrate, acetate, valerate, isovalerate, and acetate: propionate ratio and glycogenic:non-glycogenic fatty acids. Treatments had no significant effect on milk production and composition. Although, milk production in the cows fed diet containing molasses and barley grain was higher than that of control group. The serum concentration of albumin, glucose and urea nitrogen in was not significantly affected by the type of carbohydrate source. Compared to the control group, the addition of molasses caused a significant increase in serum total protein concentration (P <0.05). Economic calculations showed that the addition of molasses or barley grain to diets containing slow release urea increased net income.

The results of the present study demonstrated that the addition of carbohydrate sources with degradability higher than corn grain in dairy cow diets include slow release urea (Nitroza®) can improve nutrients utilization efficiency and increase farmer income.

One of the limitations of conventional urea usage in ruminant diet is rapid hydrolysis and increase in ruminal ammonia concentration and its lack of synchrony with carbohydrate degradation and microbial growth in the rumen. An alternative strategy is continuous supply of nitrogen using slow release urea (SRU) and gradual release of ammonia in the rumen. Sugar-containing liquid feeds can increase the energy density of the diet, stimulate dry matter intake (DMI), and serve as carriers for fat, non-protein nitrogen (NPN), and other ingredients. Sugars can change the ruminal fermentation pattern, typically decreasing ruminal NH3 concentration and increasing ruminal butyrate concentration. The purpose of this study was to investigate the effects of SRU in comparison with conventional urea, with or without the addition of molasses on the growth performance and rumen fermentation of fattening lambs.

The experiment was conducted in a completely randomized design with 5 treatments including control, two sources of non-protein nitrogen (conventional urea and SRU) with or without molasses (0 and 20 % of ration DM) and 7 replicates using 35 Arabian lambs. Forage to concentrate ratio was 30 to 70. The length of the fattening period was 105 days, including 15 days for adaptation and 90 days of data collection. At the beginning of the main period of fattening and then once a month, weighing the lambs was carried out with 14 to 16 hours of starvation. The lambs had free access to water during the test period. The lambs were fed the total mixed ration ad libitum twice daily at 0800 and 1600 hours. The digestibility coefficients of dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber, (NDF), acid detergent fiber (ADF) and ether extract (EE) were determined by the total fecal collection method. Daily feed intake, daily weight gain, feed conversion ratio, carcass compositions, meat colour, rumen and blood parameters were recorded. Data were analyzed as a completely randomized design using the General Linear Model (GLM) procedure of SAS.

Replacement of urea with SRU and the addition of molasses did not affect dry matter intake, daily weight gain, feed conversion ratio, final body weight, cold and hot carcass weight, carcass efficiency and components, meat colorimetric parameters and nutrient digestibility. The lack of difference between control and treatment groups in the growth performance could be due to sufficient supply of the microbial protein production in the rumen. Addition of SRU and molasses did not have a significant effect on dry matter intake and digestibility of nutrients. The hydrolysis rate of SRU may not be reduced to the extent that it could improve the efficiency of rumen microorganisms in utilizing the available energy source of molasses. Propionate and NH3-N concentration in the rumen increased in animals provided with NPN in comparison with the control diet. The concentration of acetate in rumen of animals fed diets containing NPN sources was lower than those on the control diet. The concentration of total volatile fatty acids in SRU diets and also diets containing conventional urea was higher than control diet. Molasses addition in diets, increased butyrate and total volatile fatty acids and decreased blood urea nitrogen concentrations, compared to control diet. Animals fed NPN diets showed higher rumen pH than the control diet. The ruminal pH decreased in diets containing molasses. Reducing the saliva secretion, due to the physical and chemical properties of molasses and the high amount of fermentable sugars supplied by molasses in the rumen, may possibly explain the decrease in the rumen pH. Animals that had received urea containing diets showed higher rumen pH presumably due to the buffering capacity of urea. An increase in ruminal ammonia concentration due to urea hydrolysis can increase the pH of the rumen by obtaining H+ by ammonia and turning it into NH4+. However, it is likely that the result reflects the higher grain content of the control diet relative to NPN containing diets.

 In general, the results of the present study showed that although replacement of soybean meal with conventional urea and/or SRU, with or without molasses, in high concentrate diets, influenced some rumen fermentation and blood metabolites, but these changes were not large enough to improve fattening performance, carcass characteristics and nutrient digestibility.