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

This study was carried out to investigate the chemical composition, antioxidant properties and phenolic compounds of Pistacia atlantica leaf at different stages of growth. Intestinal digestibility of determined by nylon bags method.  In order to prepare experimental treatments, Pistacia atlantica leaf (PAL) were collected and dried in three stages (early growing season, mid and end of growing season) from foothills of the around the city of Birjand. The treatments were: 1. PAL in early growing season, 2. PAL in middle of growing season, and 3. PAL at the end of growing season. Neutral detergent fiber and acid detergent fiber was determined. The total amount of phenolic compounds was measured. The total amount of tannins was obtained by calculating the difference between before and after the reaction with polyvinyl pyrrolidone (PVP). Condensed tannin was measured. Antioxidant activity was measured by 2, 2 diphenyl-1-picaril hydrazil (DPPH). To investigate nutritional value of Pistacia atlantica leaf (PAL) by nylon bags method, two Holstein cows fitted with a flexible rumen fistula, fed forage and concentrate in total mixed ration (TMR) at maintenance level twice daily. To determine degradability coefficients, 5 g of DM of PAL sample (ground using 2 mm screen mill) were placed in individual polyester bags and feed samples were incubated for 0, 2, 4, 8, 12, 16, 24, 48, 72, 96 and 120 h. Also, ruminal and post ruminal digestibility were determined with the incubation of samples for 16 hours in the rumen by Daisy system.  The results showed with the advance stage of growth increased, percentage of dry matter, Ash, NDF and ADF. The highest amount of dry matter belonged to the end of the growing season (49.41%) and the lowest was related to the beginning of the growing season (19.51%). The highest amount of crude protein observed at the first stage (early growth) (16.41%) and the lowest at the end of the growing season (P<0.05). With the advancement of the growth stage, the percentage of NDF and ADF was increased (P <0.05). The highest average crude fat was related to the second stage (5.62%) and the lowest average was observed in the first stage (1.82%). The highest average ash was related to the end of growing season (7.27%) and the lowest average was observed in the first stage (5.58%). The highest antioxidant and phenolic compounds was observed in the early stages of growth, this amount decreased in the third stage. The most unsaturated fatty acids of this oil were linolenic acid (26.54%), linoleic acid (10.88%) and oleic acid (12.5%).Also the most saturated fatty acid of this oil was palmitic acid (18.02%). Pistacia leaf oil used in the experiment was contain a 44.85 % saturated fatty acids, 17.83 % unsaturated fatty acid with one double bond, 10.88 % unsaturated fatty acid with two double bonds and 26.54 % unsaturated fatty acids with three double bonds. With increasing incubation time degradability of dry matter and crude protein increased. The rapid part degradation of the dry matter was 28.33% and its effective degradation at the passage rates of 0.04, 0.06 and 0.08 was 48.29, 43.39 and 40.40% respectively. The lowest constant degradation rate (c) was found for crude protein (0.0137). Most effective degradability was observed in 4% pass rate. The effective degradation rate was reduced by increasing the pass rate. Ruminal digestibility of dry matter and crude protein was higher than digestibility of post-ruminal. Overall, the digestibility of dry matter in the total digestive tract was higher than crude protein digestibility. This is due to the high rumen digestibility of dry matter compared with the digestibility of crude protein. Based upon the present research it is concluded that Pistacia atlantica leaf has good degradability. It has high nutritional value and compatible or even is a good alternative to conventional feed ingredients in livestock feed. Also, Pistacia atlantica leaf is rich in phenolic compounds and antioxidant, and it can be used as an alternative to synthetic antioxidants. Due to having about 55.25 percent unsaturated fatty acids, it has a high nutritional value and could be used in livestock diets in order to enrich and enhance oxidative stability of animal products.

The genus of Pistacia which contains 11 or more species belongs to Anacardiaceae family (Karimi et al., 2009). One of the most widely distributed species of Pistacia is Pistacia atlantica which is called “Baneh” in Iran and is the most economically important tree species in many rural areas (Pourreza et al., 2008). The fruit of wild pistachio is used by natives as flavor in food after grinding it and it is used for its oil, although the fruit is small and not commercially valuable. Tree nuts and their oils contain several bioactive and health-promoting components. Dietary consumption of tree nut oils may have even more beneficial health effects than consumption of whole tree nuts, possibly due to the replacement of dietary carbohydrates with unsaturated lipids and/or other components present in the oil extracts (Hu and Stampfer 1999).This study was carried out to evaluate and compare the quality of phenological stages, antioxidant properties and intestinal digestibility of Pistacia atlantica by nylon bags method.
Material and In order to prepare experimental treatments, Pistacia atlantica was collected and dried in three stages (early growing season, mid and end of growing season) from foothills of the around the city of Birjand. The treatments were: 1. pistachio fruit in early growing season, 2. pistachio fruit in middle of growing season, and 3. pistachio fruit at the end of growing season. Approximate analysis of samples was undertaken by AOAC (2005). Neutral detergent fiber and acid detergent fiber was determined by method of Van Soest (1991). The total amount of phenolic compounds was measured by the method of Folin ciocalteu (Marino et al., 2004). The total amount of tannins was obtained by calculating the difference between before and after the reaction with Polyvinyl pyrrolidone (PVP) (Makar et al., 1993). Condensed tannin was measured by the method of Porter et al. (1986). The antioxidant activity was measured by the method of Turkmen and colleagues (2006). Degradability parameters of the samples were measured after incubation for 0, 2, 4, 8, 16, 24, 48, 72, 96 & 120 hours in the rumen of two fistulated Holstein cows. Also, ruminal and post ruminal digestibility were determined with the incubation of samples for 16 hours in the rumen by Daisy system. The DM and CP degradation data were fitted by exponential equation P=a (1-e –ct) (17). Effective degradability (ED) were calculated using of equation ED = a {(cb) / (c k)} and taking into consideration passing rate (k) 0.04, 0.06 and 0.08 per hour.
The results showed with the advance stage of growth increased, percentage of dry matter, crude fat, NDF and ADF. The highest amount of dry matter belonged to the end of the growing season (85.29%) and the lowest was related to the beginning of the growing season (18.03%). The highest amount of crude protein observed at the first stage (early growth) (15.17%) and the lowest at the mid of the growing season (P Based upon the present research it is concluded that Pistacia atlantica is rich in phenolic compounds and antioxidant, and it can be used as an alternative to synthetic antioxidants. Also, due to having about 83 percent unsaturated fatty acids, it has a high nutritional value and could be used in livestock diets in order to enrich and enhance oxidative stability of animal products.

Cultivated alfalfa (Medicago sativa L.) is the main, most of the time the only, forage for ruminants in Iran as well as many other parts of the world. Harvesting high quality forage is critical for Iranian dairy industry, because it affects the performance of animals and reduces amount of concentrates utilization in dairy diets. Unfortunately the most parts of the concentrates ingredients are imported. Growth stage and cutting time in the day are known as the main factors affecting alfalfa hay quality. Fiber content increases and protein fraction decrease with increasing the alfalfa maturity (31). Leaf: stem ratio, digestive behavior and availability of alfalfa hay are mainly influenced by stage of maturity and cutting time. However, there is limited published information on the effect of growth stage and cutting time on nutrient characteristics of alfalfa hay. Therefore, the objective of this study was to evaluate the chemical composition, in vitro digestibility and fermentative gas production of alfalfa hay harvested at different growth stage and cutting time through in vitro experiments.
This study was done at the Research Farm of Ferdowsi University of Mashhad. Iran. The experimental farm was divided into 3 equal parts. Each part was allocated to one of the three growth stages (early bud, late bud and early bloom). Every main plot then was divided into 2 equal parts for allocation to two cutting times (at 6.00 and 18.00 hrs.). Therefore, the six plots were randomly assigned to six treatments in a factorial arrangement of 3x2. Oven dried (65◦C for 48 h) chopped alfalfa hay samples were ground to pass through a 1-mm screen. The samples were analyzed according to the standard procedures for chemical composition (2 , 27). Procedure of in vitro gas production was performed according to Menke and Steingass (1988). Rumen fluid was obtained from three fistulated Baluchi male sheep before morning feeding. The DM degradation data were fitted to the exponential equation p = a b (1 - e-ct) (21). The in vitro dry matter, NDF and organic matter digestibility were determined according to the Arroquy et al. (2005) procedure at 0, 2, 4, 6, 8, 12, 24, 36, 48, 72, 96 hrs ofter incubation.. Test samples were incubated for different hrs and then filtered through the nylon cloth with the pore size of 44 microns. The remaining materials were dried at 60 °C for 72 hrs and utilized for the subsequent analysis according to the procedure. The digestibility data were fitted to the exponential equation D(t) = D(i). e(-k. t) I (3).
Morphological characteristics and chemical composition of the alfalfa samples are shown in Table 1. With advancing the growth stage DM content was also increased but leaf to stem ratio reduced significantly

This experiment was done to determine the effectd of growth stage on chemical composition and processing by NaOH and CaOH2 on ruminally degradability of Haloxylon sp. pasture plant in seeding stage. The enough amount of Haloxylon in 3 vegetation stages was prepared from Amari SarChah in May and October and December of 2010. The chemical composition of Haloxylon sp. was determined in three stages of vegetative growth, flowering and seeding. The processing samples of maturity stage with NaOH and CaOH2was done in plastic bags and chemical composition and degradability characteristics was determined. The level of crude protein and ash reduced with the progress in growth stage and level of neutral detergent fiber increased. In the samples processed by NaOH and CaOH2 compared with the samples which were not processed, level of crude protein and ash increased and level of neutral detergent fiber reduced. Degradation coefficient a of crude protein in the samples processed by CaOH2 significantly increased compared with other treatments. Coefficient b of crude protein processed by NaOH significantly increased compared with other samples. Degradation coefficients a andbfractionof NDF showed significant difference between the samples. Therefore, the results demonstrated that, with the increase in growth stage, protein level of Haloxylon sp. plant decreased and its NDF and ADF levels increased. Moreover, processing Haloxylon sp. pasture plant by NaOH and CaOH2 caused degradation increase of dry matter, crude protein and NDF.

This experiment were conducted to study the effect of growth stage and silage process on chemical composion and dry matter digestibility. Therefore، the cultivation of sorghum growth stages (vegetative، bloom and seeding) was harvested. The chopped forage in bloom stage was used for ensiled. After opening the door of silo، sampling were taken from different parts. Samples (fresh and Silage) after drying، were grinded with 1 mm sieve size. Degradability of DM for fresh and silage sorghum was performed by nylon bags technique. The results showed that the DM، NDF and ADF increased with age increasing. Protein crude، crude fat and total tannins significantly reduced with growth progress (P<0. 05). The ash concentration was lower in flowering stage and higher in vegetative stage. Fraction “a” and “c” and effective degradability decreased as growth progress. Crude protein content of sorghum forage significantly increased compared to silage (P<0. 05). Tannin concentration in silage decreased significantly (P<0. 05) compared to sorghum forage. The results showed that degradability parameters of the fresh and silage forage were not significantly different.

In order to determination of nutritive value of Lathyrus sativus at four stages of growth، an experiment carried out in Chalaki research station located in the west of Gorgan. This experiment was a completely randomized design by five replications. Stages of growth consisted of: vegetative growth، mid-flowering (50%)، milky seed and milky-dough seed. Dry matter (DM)، crude protein (CP)، ether extract، ash، gross energy (GE) and acid detergent fiber (ADF) were measured in the laboratory. So، digestibility dry matter (DDM) and total digestible nutrient (TDN) were calculated with accounting formula. Result of the analysis showed that DM and ADF concentration increased when plant age increased and reached to doughy stage (P<0. 05). In contrast، DDM and TDN decreased as age increased (P<0. 05). Gross energy and organic matter content were not significant different at four stages. The highest percentage CP and EE were observed in mid-flowering stage (P<0. 05). The results shown that lathyrus sativus had suitable nutritive value and the best stage for forage harvesting is mid-flowering.