Faezeh Khani; Ali Assadi-Alamouti; Behzad Khorrami
Abstract
Objective: Livestock producers in Iran face increasing challenges with forage supply due to progressively detrimental climatic changes. Due to nutrient losses during drying, and spoilage and mold during storage of fresh forage, ensiling is used to preserve and utilize forage when fresh produce is unavailable. ...
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Objective: Livestock producers in Iran face increasing challenges with forage supply due to progressively detrimental climatic changes. Due to nutrient losses during drying, and spoilage and mold during storage of fresh forage, ensiling is used to preserve and utilize forage when fresh produce is unavailable. Intercropping barley crop (Hordeum vulgare) with forage pea (Pisum arvense L.) can provide a substantial portion of the protein requirements for growing livestock and dairy cows, given its acceptable protein yield per hectare. Considering the advantages of legume-cereal forage intercropping and the widespread adoption of winter cropping for forage production nationwide, particularly in the Varamin region of Iran, optimizing the legume-cereal ratio in forage crop mixtures is essential to maximize agronomic performance, water-use efficiency, nutritional value, and suitability of the mix for animal feeding. Therefore, this study aimed to investigate the effects of different ratios of whole-crop barley to forage pea on silage fermentation quality and digestibility, and to determine the optimal mixing ratio.
Method: Whole crop barley and forage pea were harvested at specific growth stages (early dough stage for barley and mid-flowering to late flowering/early pod formation for forage pea). The experiment consisted of four treatments: 1) 100% barley silage, 2) 80% barley + 20% forage pea silage, 3) 70% barley + 30% forage pea silage, and 4) 60% barley + 40% forage pea silage, with three replicates in a completely randomized design. Ensiling was carried out in 10-liter plastic mini-silos. After 60 days of ensiling, the silos were opened and sampled for analysis of crude ash, ether extract (EE), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent insoluble nitrogen (ADIN), lignin (ADL), water-soluble carbohydrates (WSC), ammonia N and volatile fatty acids. An in vitro gas production test was used to compare treatments for gas production kinetics, and estimated digestibility, metabolisable energy, and short-chain fatty acid concentrations.
Result: With the increase in the proportion of forage pea, the dry matter content decreased while pH increased. The inclusion of forage pea in the mixture tended to increase crude protein and crude ash contents (P < 0.10). However, the values of EE, ADF, NDF, ADL, and ADIN were not affected by the forage pea (P > 0.05). Furthermore, increasing the proportion of forage pea significantly elevated the concentration of ammonia-N in the silage (P<0.05). No significant differences were observed among silages in terms of acetic, propionic, and butyric acid concentrations, with the levels of these volatile fatty acids falling within the range typically found in well-fermented silages. The treated silage containing 20% forage pea exhibited higher gas production volume, organic matter digestibility, metabolizable energy, and short-chain fatty acids than forage barley silage as the sole crop (P < 0.05).
Conclusions: Overall, the results demonstrated that mixing forage pea with whole crop barley during ensiling improved its nutritional value by enhancing CP content and reducing fiber levels, while taking advantage of barley forage, such as higher dry matter and WSC. This approach could serve as a winter-cropping strategy in semi-arid climates, improving feed quality, reducing costs, and promoting environmental sustainability. The present study suggested a 20% forage pea inclusion level for mixing with barley forage in laboratory conditions. However, this proportion should be further studied in animal trials.
Nooshin Assadi-Fakhrnejad; Ali Assadi-Alamouti; Behzad Khorrami
Abstract
Objective: The productivity and nutritional quality of ensiled forages, the quality of silage fermentation and its loss are improved by forage harvesting at an appropriate stage of maturity, while, forage intercropping strategies that take the advantage of the additive characteristics of different plant ...
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Objective: The productivity and nutritional quality of ensiled forages, the quality of silage fermentation and its loss are improved by forage harvesting at an appropriate stage of maturity, while, forage intercropping strategies that take the advantage of the additive characteristics of different plant species also enhance the quality of the forage product. The objective of this study was to evaluate the effect of forage maturity at harvest and intercropping on ensiling characteristics, effluent production, and in vitro (laboratory) digestibility in three small-grain forages (barley, triticale and oat).Method: Whole plant barley was harvested at early heading and hard dough stage of growth; whole plant triticale was harvested at the tillering and soft dough stage, and the oats forage was harvested at the tillering and stem elongation stages. The intercropping treatments consisted of 53% barley, 33% triticale, and 14% oat, harvested at the above-mentioned stages. The experiment was a 2×4 factorial arrangement in a completely randomized design with eight treatments and three replicates. Results: Dry matter (DM), organic matter (OM), and crude protein (CP) yields increased with growth stages in triticale, oat, and the mixed crop. The highest DM (32.1%) was found in the mixed crop in the second harvest stage and the lowest (13.5%) was observed in the first harvest stage in oats (P<0.001), whereas the highest CP (19.3 %) was obtained from oats in the first harvest, and the lowest (10.8%) from barley in the second harvest stage (P<0.001). The lowest NDF content (49.5%) was observed in oats and the highest (58.2%) in barley (P<0.001). The interaction effect of forage type and harvest time on DM, CP, and ADF contents was significant; however, the other chemical components (ash, lignin, acid-, and neutral-detergent insoluble nitrogen, crude fat, and water soluble carbohydrates (WSC)) were similar between the two harvest stages. Overall, late harvesting increased lignin and decreased CP, WSC, and NDF. Intercropping of oats with the other crops increased CP and improved in vitro digestibility, and it reduced silage NDF content. The silages of the second harvest crops produced no effluent, had an appropriate pH (close to 4.2) and an ammonia nitrogen level of less than 10% total nitrogen, highlightimg good fermentation in the silages with higher DM content.Conclusions: Results from this study indicated that the second harvest stage (hard dough in barley, soft dough in triticale, and stem elongation in oats) was the appropriate time for harvesting small grain forages whether ensiled as a sole forage or intercropped as it maximized the yield of OM, CP, energy, and digestible DM per hectare. As the yield performance of triticale was superior to that of barley, it is recommended to include triticale as the main crop in intercropping systems.
MH Heidary Far; Mohammad Ali Norouzian; Behzad Khorrami
Abstract
Objective: This study aimed to investigate the chemical composition, dry matter (DM) and crude protein (CP) degradability, and gas production parameters of Lemna minor (duckweed) in ruminant nutrition.
Methods: In the first phase, the chemical composition and mineral content, gas production parameters, ...
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Objective: This study aimed to investigate the chemical composition, dry matter (DM) and crude protein (CP) degradability, and gas production parameters of Lemna minor (duckweed) in ruminant nutrition.
Methods: In the first phase, the chemical composition and mineral content, gas production parameters, and degradability of DM and CP of Lemna minor (collected from two regions: Rasht and Varamin) as well as alfalfa forage were determined using standard analytical methods. In the second phase, based on the CP content of Lemna minor, the fermentative value of gas production was measured for experimental diets consisting of a control group (60% concentrate and 40% alfalfa) and treatments in which alfalfa was replaced with Lemna minor at levels of 25%, 50%, 75%, and 100%.
Results: The CP content in whole Lemna minor from Varamin was significantly higher than that of whole Lemna minor from Rasht and alfalfa forage (P<0.05). The neutral detergent fiber content of whole Lemna minor from both Rasht and Varamin was higher than that of alfalfa (P<0.05). Crude ash content in whole Lemna minor from Varamin was higher than in the Rasht sample and alfalfa (P<0.05). The concentrations of macro-minerals (calcium, phosphorus, magnesium, and potassium) and micro-minerals (copper, zinc, iron, and manganese) differed between the two Lemna minor samples. Across all incubation times, gas production was significantly greater in alfalfa than in Lemna minor (P<0.05). Similarly, the potential and rate of gas production, metabolizable energy (ME) content, and organic matter digestibility were all higher in alfalfa compared with Lemna minor (P<0.05). Methane gas production from Lemna minor was also lower than from alfalfa (P<0.05). The rapidly degradable fraction of DM and CP in Lemna minor (32.3% and 27.0%, respectively) was significantly higher than that in alfalfa (22.6% and 25.9%, respectively; P<0.05). However, the slowly degradable fraction, the degradation rate constant, and the effective degradability at passage rates of 0.02, 0.04, and 0.06 per hour for both DM and CP were higher in alfalfa than in Lemna minor from Rasht (P<0.05). Replacing alfalfa with Lemna minor in the experimental diets significantly reduced gas production at various incubation times, particularly at higher replacement levels (P<0.05). Moreover, the gas production potential parameter (b) and ME content were highest in the control group without Lemna minor and lowest in the treatment where alfalfa was completely replaced by Lemna minor (P<0.05).
Conclusion: Considering its crude protein content, mineral concentrations, and degradability characteristics, Lemna minor has potential as a valuable feed ingredient in ruminant diets. Nevertheless, further studies, especially under practical farm conditions, are recommended before its widespread application.
Behzad Khorrami; Seyed Alireza Vakili
Abstract
Objective: Cattle are the major reservoirs of the pathogenic bacteria Escherichia coli O157:H7, and approximately 30% of feedlot cattle shed E. coli O157:H7. Feedlot calves are fed high concentrate diets in order to increase feed efficiency. It has been reported that populations of E. coli O157:H7 were ...
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Objective: Cattle are the major reservoirs of the pathogenic bacteria Escherichia coli O157:H7, and approximately 30% of feedlot cattle shed E. coli O157:H7. Feedlot calves are fed high concentrate diets in order to increase feed efficiency. It has been reported that populations of E. coli O157:H7 were higher in grain-fed than in forage-fed cattle, and when cattle were abruptly switched from a high concentrate diet to an all-forage diet, total E. coli populations declined 1000-fold. Therefore, strategies that decrease E. coli O157:H7 prior to slaughter will reduce human exposures to this virulent pathogen. However, a dietary switch to forage in feedlot calves is not advocated due to feasibility, weight loss and other logistical issues, other feedstuffs rich in phenolics such as essential oils (EO) could be a more feasible alternative strategy to reduce E. coli O157:H7 populations. Data available indicate a strong bactericidal activity of EO against pathogenic bacteria such as E. coli O157:H7. Among the EO, thyme (THY) and cinnamon (CIN) oil have attracted considerable attention in several literatures due to their potential antibacterial activity against ruminal microbes. The aim of the present research was to evaluate the effects of THY and CIN on E. coli O157:H7 population in the rumen and feces of feedlot calves fed high-concentrate diets.
Method: Twenty-four growing Holstein calves (214±16 kg initial BW) were used in a completely randomized design and received their respective dietary treatments for 45 d. Treatments were: 1-control (no additive), 2-THY (5 g/d/calf), 3-CIN (5 g/d/calf) and 4- forage (sudden switch from grain diet to forage diet in the last ten days of experiment; as positive control for relative abundance of E. coli O157:H7 in the rumen and feces). Calves were fed ad libitum diets consisting of 15% forage and 85% concentrate. Ruminal and fecal samples were collected from calves at the end of the experiment. Quantitative detection of E. coli O157:H7 in samples were done using specific primers and real-time PCR method.
Results: The average dry matter intake (DMI) and daily weight gain (ADG) of feedlot calves from day 36 to day 70 of the experiment was not affected by the experimental treatments. However, DMI and ADG decreased, and feed conversion ratio increased in calves fed forage treatment from day 71 to 80 (P<0.05). Supplementation of THY or CIN decreased the relative abundances of E. coli strain O157:H7 (rbfE) in rumen contents (P<0.05), while they did not affect strain O157:H7 (iudA). But forage treatment decreased the population of both strains of E. coli O157:H7 in the rumen fluid of feedlot calves compared to the control treatment (P<0.05). The experimental treatments also reduced the relative abundances of both strains of E. coli O157:H7 in the rumen and feces of feedlot calves compared to the control treatment (P<0.05).
Conclusion: The results showed that the use of thyme and cinnamon essential oil in feedlot calves diet can be a more suitable way compared to nutritional methods such as abruptly switched from a high grain diet to an all-forage diet to reduce the population of pathogenic bacteria Escherichia coli O157:H7 in the rumen and reduction of its shedding in feces.
Behzad Khorrami; Seyed Alireza Vakili; mohsen danesh mesgaran
Abstract
Introduction: Today, the use of antimicrobial agents such as antibiotics in livestock diets is facing reduced social acceptance because of the appearance of residues in milk and meat, and therefore, ruminant nutritionists are seeking for appropriate alternatives for these feed additives. The study of ...
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Introduction: Today, the use of antimicrobial agents such as antibiotics in livestock diets is facing reduced social acceptance because of the appearance of residues in milk and meat, and therefore, ruminant nutritionists are seeking for appropriate alternatives for these feed additives. The study of essential oils (EOs) as natural feed additives capable of improving rumen microbial fermentation has taken into consideration by nutritionists. Among the EOs, thyme (THY) and cinnamon (CIN) oil have attracted significant attention due to their antimicrobial activity against ruminal microorganisms. Therefore, more research is required to understand their impacts on rumen microbial fermentation in ruminants. Moreover, to the best of our knowledge, few studies has synchronously compared the influences of THY and CIN on rumen fermentation and microorganisms. This study was conducted to evaluate the effect of THY and CIN on performance, and rumen microbial fermentation under in vitro and in vivo conditions.
Materials and methods: In the in vitro experiment, different concentrations (0, 125, 250, 500, and 1000 mg/l) of THY and CIN were incubated for 24-h in batch culture. In the in vivo study 18 growing Holstein calves were used in a completely randomized design to examine effects of supplementing a basal diet (CON) with thyme oil (THY, 5 g/d/calf) or cinnamon oil (CIN, 5 g/d/calf) on performance and rumen microbial fermentation. Calves were fed ad libitum diets consisting of 15% forage and 85% concentrate for 80 d.
Results and discussion: The high concentration of THY and CIN (1000 mg/l) inhibited rumen microbial fermentation thereby decreasing total gas production and DM disappearance at 24 of incubation, and total VFA concentration. Cinnamon oil at 1000 mg/l increased final pH of batch culture (P<0.05). The lower concentration of THY and CIN (125 and 250 mg/l) decreased the acetate to propionate ratio (P<0.05), without reducing VFA concentration. Supplementation of THY or CIN did not affect DMI and ADG. There were also no effects of EOs on ruminal pH, rumen concentrations of ammonia nitrogen and total VFA; whereas molar proportion of acetate and ratio of acetate to propionate decreased (P<0.05), and the molar proportion of propionate increased (P<0.05). Rumen molar proportion of butyrate was significantly increased (P<0.05) by adding CIN. The population of protozoa and methanogens bacteria decreased in the rumen of calves receiving EOs (P<0.05). Ruminal population of Fibrobacter succinogenes was not affected by treatments, but populations of Ruminococcus albus and flavefaciens decreased by THY and CIN (P<0.05).
Conclusion: Based on the results of the present study, although dietary addition of THY and CIN did not have a significant effect on the performance of feedlot calves, but it improved the rumen fermentation properties, which may be considered as potential alternatives for antibiotics in beef production systems.
Seyed Hamid Mousavi Esfiokhi; Mohammad Reza Sahlabadi; Behzad Khorrami
Abstract
In order to investigate the chemical and nutritional characteristics of pea pod silage (PPS) and its effect on the performance of fattening lambs, 24 Zandi male lambs (initial BW, 33.5 ±1.5 kg) were used in a completely randomized design over 75 days. Experimental treatments were: 1) control; ...
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In order to investigate the chemical and nutritional characteristics of pea pod silage (PPS) and its effect on the performance of fattening lambs, 24 Zandi male lambs (initial BW, 33.5 ±1.5 kg) were used in a completely randomized design over 75 days. Experimental treatments were: 1) control; (basal diet) 2- pea pod silage (PPS replaced wheat straw and alfalfa in the basal diet). The amount of dry matter (DM), crude protein, ether extract, ash, neutral detergent fiber and acid detergent fiber of PPS were determined 20, 11.8, 1.8, 8, 62 and 20.2 percent, respectively, and pH was 6.02. The rumen degradability potential of DM and in vitro gas production potential of PPS after 96 h of incubation were estimated 83 and 58.6 percent, respectively. The use of PPS in fattening lambs rations improved the final body weight and increased the daily weight gain (P<0.05). The amount of DM digestibility was affected by the treatment (P<0.05), but digestibility of other nutrients was not affected by the experimental treatment. Blood parameters (cholesterol, triglyceride, HDL and LDL) were not affected by the experimental treatments, except for the glucose, which significantly decreased by feeding PPS (P<0.05). The experimental treatments had no significant effect on carcass traits. Based on the results of this study, the use of pea pod silage as a cost-effective alternative forage in replacement with common forages such as wheat straw and alfalfa can improve the performance of fattening lambs.
Behzad Khorrami
Abstract
Effect of sodium bicarbonate and pHmax buffer supplement on milk fat synthesis under milk fat depression conditions, using of 24 Holstein lactating cows were investigated in a completely randomized block design. Milk fat depression was induced in all cows for 10 d by feeding a diet containing high levels ...
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Effect of sodium bicarbonate and pHmax buffer supplement on milk fat synthesis under milk fat depression conditions, using of 24 Holstein lactating cows were investigated in a completely randomized block design. Milk fat depression was induced in all cows for 10 d by feeding a diet containing high levels of starch. The experiment was conducted in two periods including: first period (day 1 to 20), allocation of cows to the treatments 1) control, 2) basal diet + 0.8% pHmax and 3) basal diet + 0.8% sodium bicarbonate and in the second period (days 21 to 30), all cows were fed the control diet. Buffer supplements increased milk fat concentration, without affecting dry matter intake, milk yield, and milk protein and lactose concentrations. The concentration of total trans fatty acids decreased in the experimental treatments compared to the control. The trans -10: trans -11 ratio was lower in cows receiving the buffer supplements compared with cows receiving the control, which indicating the effect of these compounds on the improvement of milk fat synthesis by stimulating normal fatty acid biohydrogenation pathways in the rumen. Addition of buffer supplements increased milk fat synthesis, which persisted for one week after cessation of mentioned compounds. Therefore, using of sodium bicarbonate and pHmax can maintain milk fat in dairy cows fed with diets containing high starch and under milk fat depression conditions. Also, using of pHmax reduces the costs of using common buffer compounds such as sodium bicarbonate.