The effects of Saccharomyces cerevisiae on performance and nutrients digestibility in broilers fed with diet containing different levels of phosphorous

The effects of yeast culture (YC) with different levels of NPP (non phytate phosphorus) on performance, tibia and blood parameters and ileal digestibility of nutrients were investigated in broilers. A total of 720 one-day-old male broiler (Ross) chicks were divided into 48 groups and fed with 12 diets (4 groups per diet) for 42 days. The experimental design was a randomized complete block with a 3 × 4 factorial arrangement of treatments. The 12 treatments consisted of: 3 levels of NPP (normal, 80 and 60% normal level) and 4 levels of YC (0.0, 0.15, 0.3 and 0.45 % of diet). The results of this study showed that there were significant interactions (p<0.05) between NPP level and the concentration of YC in the diet with body weight gain (BWG) and feed conversion ratio (FCR) during the 42 days of the experiment. In the lower levels of NPP, the improvement of FCR was dose dependent on YC. No NPP dietary x YC combination interactions were found in the other measured traits. The lower levels of NPP significantly (p<0.05) decreased ileal digestibility of crude protein (CP) and calcium (Ca). The addition of YC significantly (p<0.05) increased ileal digestibility of both P and Ca. The enhancement of NPP dietary significantly (p<0.05) increased the concentration of P, Ca and ash in the tibia. Only birds fed with the diets containing 0.45% YC significantly had (p<0.05) higher ash percentage than the other groups. Serum Ca and P were significantly (p<0.05) affected by different levels of NPP in the diet. The effect of YC on concentration of serum P and total protein was significant (p<0.05). In conclusion, the increased retention of P, CP and mineral utilization in deficient-NPP diets by YC resulted in increased availability of P and Ca to the broilers, which could have led to improved growth performance.Key words: Yeast culture, phosphorus, broilers, performance, digestibility

The effects of different levels of sodium caseinate on rumen fermentation pattern, digestibility and microbial protein synthesis of Holstein dairy cows

This study was conducted to investigate the effects of different levels of peptide supplementation on rumen fermentation pattern, digestibility and microbial protein synthesis. Three rumen-cannulated Holstein dairy cows were used in a 3 × 3 Latin square experiment within 21 days period. The ruminal infusion of sodium caseinate (CN) was 0 (control), 50 and 100 g/d. Dry matter intake, milk yield and composition , total tract apparent digestibility of nutrient, rumen parameters and purine derivatives inurine of cows were measured. Results showed that dairy cows received sodium caseinate, had significantly increased microbial protein synthesis, milk fat yield, acetate and branched chain fatty acids concentrations in rumen fluid and fiber digestibility compared with the control treatment (P <0.05). CN significantly affected the concentrations of rumen ammonia nitrogen (NH3-N), rumen peptide nitrogen (Pep-N) and the ratio of rumen ammonia nitrogen/ rumen peptide nitrogen (P < 0.05) and consequently blood urea nitrogen, milk urea nitrogen and urinary urea nitrogen concentrations. However digestibility of dry matter and crude protein did not differ among treatments. In conclusion, if the optimum level of NH3-N/Pep-N was the best compromise among the need for rumen fermentation, microbial protein synthesis and nitrogen excretion through urine in animal, the recommended level from this study would be 0.86 in rumen fluid

Effect of urea supplementation in diet based on barley grain or corn silage on performance, digestion, rumen fermentation and microbial protein synthesis in Holstein bull calves

This study was aimed to evaluate the effect of non-protein nitrogen source of urea with barley grain (BG) or corn silage (CS) based diet in Holstein bull calves. Nutrient digestibility, rumen fermentation activities, microbial nitrogen yield (MN) and blood metabolites were determined. Holstein bull calves (14), weighing 126 ± 4.2 kg were allocated in 2 different diets based on BG or CS for 9 weeks. Diets were based on rolled barley grain (BG) and on finely chopped corn silage (CS). Both diets were supplemented with 7.5 g/kg urea on DM basis. Intake and performance of animal did not differ between diets, whereas digestibility of neutral detergent fiber (NDF) decreased in BG diet. Ruminal concentration of propionate and blood glucose concentration increased in BG calves, whereas ruminal pH and acetate concentration increased in CS fed calves. The ruminal NH3-N was increased in CS diet, while excretions of allantoin, purine derivatives and estimated MN yield through urine were greater in BG diet vs. CS diet. In conclusion, the results suggested that increased urinary PD excretion and consequently increased estimated MN yield value for BG diet presented more potential for this diet to be synchronized with urea in calves’ rumen digestion

Influence of barley grain particle size and treatment with citric acid on digestibility, ruminal fermentation and microbial protein synthesis in Holstein calves

Chemical and physical treatments of barley grain increase ruminally resistant starch and can improve the rumen fermentation pattern. The objective of the present study was to evaluate the effects of chemical (addition of citric acid, CA) and physical (grinding to two different particle sizes, PS) treatment of barley grain on performance, rumen fermentation, microbial protein yield in the rumen and selected blood metabolites in growing calves. In all, 28 male Holstein calves (172 ± 5.1 kg initial BW) were used in a complete randomised design with a factorial arrangement of 2 barley grain particle sizes × 2 levels of citric acid. The diets were as follows: (i) small PS (average 1200 μm) barley grain soaked in water (no CA addition); (ii) small PS barley grain soaked in a CA solution (adding 20 g CA/kg barley); (iii) large PS (average 2400 μm) barley grain soaked in water (no citric acid addition) and (iv) large PS barley grain soaked in a citric acid solution (adding 20 g CA/kg barley). Barley grain was then incorporated at 35% in a total mixed ration and fed to the calves for 11 weeks. Feeding small PS barley decreased feed intake ( P = 0.02) and average daily weight gain ( P = 0.01). The addition of CA to barley grain did not affect intake but increased weight gain ( P<0.01) and improved feed to gain ratio ( P = 0.03). Digestibility of organic matter and NDF tended ( P<0.10) to increase, whereas faecal scoring was improved ( P = 0.03) and the presence of undigested grain particles in faeces was reduced ( P<0.01) with CA-treated barley grain. Glucose and urea concentrations were increased (P<0.01) in the blood of calves fed the CA-treated barley grain. Ruminal pH tended ( P = 0.08) to be decreased with more finely ground barley and was increased when barley grain was treated with CA. Total volatile fatty acid concentrations in the rumen did not differ among treatments ( P>0.05). However, the molar proportion of propionate was increased ( P = 0.03) when barley was more finely ground, and that of acetate was increased ( P = 0.04) when CA was added to barley grain. The ruminal concentration of ammonia nitrogen was increased ( P<0.01) and microbial nitrogen synthesis in the rumen tended to decrease by adding CA to barley. Treating barley grain with citric acid increased fibre digestibility of total mixed rations, attenuated the decrease in ruminal pH, and improved weight gain and feed efficiency in male Holstein growing calves fed a high-cereal diet (550 g cereal grain/kg diet)

Influence of barley grain particle size and treatment with citric acid on digestibility, ruminal fermentation and microbial protein synthesis in Holstein calves

8 páginas, 4 tablas.Chemical and physical treatments of barley grain increase ruminally resistant starch and can improve the rumen fermentation pattern. The objective of the present study was to evaluate the effects of chemical (addition of citric acid, CA) and physical (grinding to two different particle sizes, PS) treatment of barley grain on performance, rumen fermentation, microbial protein yield in the rumen and selected blood metabolites in growing calves. In all, 28 male Holstein calves (172±5.1 kg initial BW) were used in a complete randomised design with a factorial arrangement of 2 barley grain particle sizes×2 levels of citric acid. The diets were as follows: (i) small PS (average 1200 m) barley grain soaked in water (no CA addition); (ii) small PS barley grain soaked in a CA solution (adding 20 g CA/kg barley); (iii) large PS (average 2400 m) barley grain soaked in water (no citric acid addition) and (iv) large PS barley grain soaked in a citric acid solution (adding 20 g CA/kg barley). Barley grain was then incorporated at 35% in a total mixed ration and fed to the calves for 11 weeks. Feeding small PS barley decreased feed intake (P=0.02) and average daily weight gain (P=0.01). The addition of CA to barley grain did not affect intake but increased weight gain (P0.05). However, the molar proportion of propionate was increased (P=0.03) when barley was more finely ground, and that of acetate was increased (P=0.04) when CA was added to barley grain. The ruminal concentration of ammonia nitrogen was increased (P<0.01) and microbial nitrogen synthesis in the rumen tended to decrease by adding CA to barley. Treating barley grain with citric acid increased fibre digestibility of total mixed rations, attenuated the decrease in ruminal pH, and improved weight gain and feed efficiency in male Holstein growing calves fed a high-cereal diet (550 g cereal grain/kg diet).Financial support from the Department of Research in Arak University (Arak, Iran) is appreciated deeply. Special thanks to Dr A. Fazlali (deputy of research and technology of Arak University) for his assistance with performing the experiment. The work is part of a companion project between Arak University and a commercial animal farm (Shahrak-Laban Farm, Qom). Dr Moallemian for assistance in laboratory measurements, B. Sajedi MSc in University of Tehran and the animal farm staff are gratefully acknowledged.Peer Reviewe

Influence of roasting, gamma ray irradiation and microwaving on ruminal dry matter and crude protein digestion of cottonseed

The aim of the current study was to compare the effect of different physical processing methods including roasting at 140 °C for 15 (R15) or 30 minutes (R30), gamma ray irradiation (γ-irradiation) at doses of 15 (γ15), 30 (γ30) and 45 (γ45) kGy, and microwaving at 800 W for 2 (MW2), 4 (MW4) and 6 minutes (MW6) of whole cottonseed (WCS) on ruminal degradation. In vitro crude protein (CP) digestibility and gossypol contents were compared as well. In situ experiment was conducted on three permanent rumen-fistulated bulls. Gossypol content was decreased among treatments (p < 0.05). The lowest degradation rate of protein in rumen was obtained for γ45 treatment. The rate of degradation of the potentially degradation fraction was decreased for both dry matter (DM) (p = 0.002) and CP (p = 0.006) with different treatments. The lowest values for effective degradation in all passage rates were obtained with γ45. Both microwaving and γ irradiation showed difference for CP effective degradability parameter. The greatest value of in vitro CP digestibility (p < 0.05) was observed for a dose of 45 kGy gamma-irradiated cottonseed compared to untreated WCS. Based on the results, γ ray irradiation with 45 kGy was the most effective processing method in both reducing the gossypol content and escaping the protein through rumen for WCS in ruminant nutrition

Effects of fat source in calf starter on growth performance, blood fatty acid profiles, and inflammatory markers during cold season

Abstract This study was conducted to investigate the effects of supplementation of different fat sources in calf starters on growth performance, health, blood fatty acid profiles, and inflammatory markers during the cold season in dairy calves. A total of 48 Holstein calves (24 males and 24 females) were randomly assigned to 1 of 4 starter diets throughout the experiment (d 3 to 65): (1) no supplemented fat (CON), (2) 3% calcium-salts of soybean oil (Ca-SBO), (3) 3% calcium-salts of fish oil (Ca–FO), and (4) 3% mixture of Ca-SBO and Ca–FO (1.5% each, DM basis; MIX). Calves were given free access to starter feed and water and were raised individually in pens from 3 to 65 d of age. Calves fed Ca-SBO consumed a greater proportion of n-6 FA, while calves fed Ca–FO consumed a greater level of n-3 FA compared to the other dietary treatments. Fat supplementation increased the intake of linoleic acid, the major n-6 FA, with the greater intake observed in the Ca-SBO group compared to the other dietary treatments. Calves fed the Ca–FO and MIX diets consumed more long-chain n-3 FA than the other diets. In addition, calves fed Ca-SBO and Ca–FO diets consumed more starter feed and total dry matter than calves fed MIX and CON throughout the experiment (d 3 to 65). Calves fed Ca–FO had higher average daily gain throughout the trial (d 3 to 65) than the other treatment groups. Of all treatment groups, calves fed Ca–FO achieved the highest final body weight and showed the greatest feed efficiency. Random forest analysis revealed that eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and arachidonic acid were the serum levels of FA most affected by the diets. The principal component analysis of blood FA profile, blood parameters, and inflammatory markers showed distinct differences between dietary treatments. Calves fed Ca-SBO had higher plasma concentrations of linoleic acid, while calves fed Ca–FO had higher plasma concentrations of long-chain n-3 polyunsaturated fatty acids (PUFA), such as EPA, docosapentaenoic acid (DPA), and DHA than the other treatment groups. Plasma inflammatory markers were lower in calves fed Ca–FO and higher in calves fed CON than in the other treatment groups. The Ca–FO group had lower levels of inflammatory markers, including serum amyloid A, tumor necrosis factor-alpha, Interferon-γ, haptoglobin, and interleukin-6 compared to the other experimental treatments. Also, the blood malondialdehyde levels, an indicator of oxidative stress, were lower in calves fed Ca–FO compared with calves fed the other treatment diets. In conclusion, the performance of preweaned dairy calves can be improved by adding fat to their starter feed under cold conditions. Overall, the type of fat in milk may affect growth and inflammation of dairy calves before weaning under cold conditions, with n-3 FA (Ca–FO) promoting growth and reducing inflammation more effectively than n-6 FA (Ca-SBO)

Effects of supplementation level and particle size of alfalfa hay on growth characteristics and rumen development in dairy calves

The aim of this study was to assess the effects of particle size (PS) of alfalfa hay on growth characteristics and rumen development in dairy calves at two levels of alfalfa supplementation. Fifty newborn dairy calves (42.7 ± 2.2 kg BW) were used in a 2 × 2 factorial arrangement with the factors supplementation level (low, 8%; or high, 16% on DM basis) and PS (medium, 2.92 mm; or long, 5.04 mm as geometrical means) of alfalfa hay. In addition, a control group without alfalfa hay was used. Hence, treatments were: control (C); low level with medium PS (LM); low level with long PS (LL); high level with medium PS (HM) or high level with long PS (HL). Growth performance of alfalfa-fed calves did not differ from control calves, but alfalfa supplementation decreased corneum thickness of the rumen wall. In alfalfa-fed calves, post-weaning starter intake was greater for LL calves than for LM calves. During the entire rearing period, starter intake was 26–32% higher for LL and HM calves than for LM calves. Pre-weaning average daily gain was higher for LL and HM calves than for HL calves, but this effect was not persistent over the entire rearing period. Final body weight decreased from 86 to 79 kg when the level of long PS alfalfa hay increased from 8 to 16%, but increased from 78 to 87 kg when the level of medium PS alfalfa increased from 8 to 16%. Regardless of PS and level, morphometric characteristics of rumen wall were generally similar among alfalfa feeding groups, but corneum thickness decreased from 8.7 to 6.1 µm with greater PS at the low level. These results indicate that adequate, but not excessive, physical stimulation is required for appropriate rumen development and growth performance of dairy calves