Effect of increasing inclusion rates of tofu by-product in diets of growing pigs on nitrogen balance and ammonia emission from manure.

To reduce competition with human-edible feed resources, it is of interest to incorporate by-products from the food industry in animal feeds. The current research investigated the effect of including increasing amounts of tofu by-product (TF) in practical pig diets on animal performance, nitrogen balance and ammonia emissions from manure. Two experiments were conducted including a control diet without TF, containing 160 g/kg dietary non-starch polysaccharides (NSPs) and three diets including 122, 246 and 360 g TF/kg DM (TF122, TF246 and TF360, respectively) to reach 220, 280 and 360 g/kg NSP. All diets had the same level of CP and protein digestible in the small intestine which particularly was realized by replacing rice bran with TF. Animal performance was assessed in a first experiment with 40 growing barrows with initial BW of 26.6 ± 1.80 kg (M ± SD) being allocated to the 4 treatments, during 2 growth phases (i.e. until 50 kg BW and from 50 to 80 kg BW). In the growth phase until 50 kg, feed intake and average daily gain (ADG) were linearly reduced by dietary TF inclusion, while this negative impact disappeared during the second growth phase (50 to 80 kg BW). Tofu by-product inclusion even positively affected the feed conversion ratio during this second growth phase (3.4 to 2.7 kg feed/kg ADG for 0 to 360 g/kg dietary TF). Over the entire growth period, performance and feed intake were negatively affected at the highest dietary TF level. Experiment 2 was conducted to assess digestibility, nitrogen balance and ammonia emission from manure. For this purpose, 16 pigs with BW of 62.8 ± 3.6 kg (M ± SD) were assigned to either 1 of the 4 treatments. There was no difference in total tract apparent digestibility of dietary organic matter or CP, while NDF digestibility increased with increasing TF level, suggesting increasing importance of the hindgut fermentation when digesting diets with increasing TF levels. Nevertheless, this was not reflected in increasing levels of faecal volatile fatty acids or purines, nor in reduced manure pH. As a result, ammonia emission from slurry was not reduced through dietary TF inclusion, despite the linear decrease in urinary nitrogen. In conclusion, TF can be included in pigs' diets up to an inclusion rate of 25% without risk of impaired animal performance; however, this dietary strategy fails to mitigate ammonia emission from slurry.

Biogas production from vietnamese animal manure, plant residues and organic waste: influence of biomass composition on methane yield.

Anaerobic digestion is an efficient and renewable energy technology that can produce biogas from a variety of biomasses such as animal manure, food waste and plant residues. In developing countries this technology is widely used for the production of biogas using local biomasses, but there is little information about the value of these biomasses for energy production. This study was therefore carried out with the objective of estimating the biogas production potential of typical Vietnamese biomasses such as animal manure, slaughterhouse waste and plant residues, and developing a model that relates methane (CH4) production to the chemical characteristics of the biomass. The biochemical methane potential (BMP) and biomass characteristics were measured. Results showed that piglet manure produced the highest CH4 yield of 443 normal litter (NL) CH4 kg(-1) volatile solids (VS) compared to 222 from cows, 177 from sows, 172 from rabbits, 169 from goats and 153 from buffaloes. Methane production from duckweed (Spirodela polyrrhiza) was higher than from lawn grass and water spinach at 340, 220, and 110.6 NL CH4 kg(-1) VS, respectively. The BMP experiment also demonstrated that the CH4 production was inhibited with chicken manure, slaughterhouse waste, cassava residue and shoe-making waste. Statistical analysis showed that lipid and lignin are the most significant predictors of BMP. The model was developed from knowledge that the BMP was related to biomass content of lipid, lignin and protein from manure and plant residues as a percentage of VS with coefficient of determination (R-square) at 0.95. This model was applied to calculate the CH4 yield for a household with 17 fattening pigs in the highlands and lowlands of northern Vietnam.

Effects of crystalline amino acid supplementation to the diet on odor from pig manure.

The objective of this study was to determine the effects of specific crystalline AA supplementation to a diet on odor emission, odor intensity, odor hedonic tone, and ammonia emission from pig manure, and on manure characteristics (pH; ammonia N; total nitrogen; sulfurous, indolic, and phenolic compounds; and VFA concentrations). An experiment was conducted with growing pigs (n = 18) in a randomized complete block design, with 3 treatments in 6 blocks. Treatment groups were (1) a 15%-CP basal diet with 3 times the requirement of sulfur-containing AA (14.2 g/kg of diet, as-fed basis); (2) the basal diet with 2 times the requirement of Trp and Phe+Tyr (2.9 and 20.4 g/kg of diet, respectively, as-fed basis); and (3) the basal diet with AA supplementation to levels sufficient for maximum protein gain. Pigs with an initial BW of 41.2 +/- 0.8 kg were individually penned in partly slatted floor pens and offered a daily feed allowance of 2.8 times the maintenance requirement for NE (293 kJ/kg of BW(0.75)). Feed was mixed with water at 1:2.5 (wt/wt). Feces and urine of each pig was allowed to accumulate in separate manure pits under the slatted floor. After an adaptation period of 2 wk, and after cleaning the manure pits, manure was subsequently collected. In wk 5 of the collection period, separate samples were collected directly from each manure pit for odor, ammonia, and manure composition analyses. Air samples were analyzed for odor concentration and for hedonic tone and odor intensity above the odor detection threshold. Results showed that supplementing crystalline S-containing AA in surplus of the requirement increased odor emission (P < 0.001) and odor intensity (P < 0.05) and reduced odor hedonic tone (P < 0.05) from the air above the manure pits. Supplementing crystalline Trp, Tyr, and Phe in surplus of the recommended requirements did not affect odor emission, odor intensity, or odor hedonic tone. Regardless of dietary treatment, all pigs had similar performance levels. No differences were observed in ammonia emission from manure of pigs fed different levels of AA supplementation (P = 0.20). To reduce odor from pig manure, dietary S-containing AA should be minimized to just meet the recommended requirements.

Effects of dietary crude protein level on odour from pig manure.

The objective of this study was to determine the effects of dietary crude protein (CP) level on odour emission, odour intensity, hedonic tone, and ammonia emission from pig manure and on manure composition (pH, total nitrogen, ammonium, volatile fatty acids, indolic, phenolic and sulphur-containing compounds). An experiment was conducted with growing pigs (n = 18) in a randomised complete-block design with three treatments in six blocks. Treatment groups were 12%, 15% and 18% CP diets. Barley was exchanged for soya-bean meal. Crystalline amino acids (AA) were included in the 12% CP diet up to the level of pigs' requirement; the same amount of AA was added to the 15% and 18% CP diets. Pigs with an initial body weight (BW) of 36.5 ± 3.4 kg (mean ± s.d.) were individually penned in partly slatted floor pens and offered a daily feed allowance of 2.8 × maintenance requirement for net energy (NE: 293 kJ/kg BW0.75). Feed was mixed with water, 1/2.5 (w/w). Faeces and urine of each pig were accumulated together in a separate manure pit under the slatted floor. After an adaptation period of 2 weeks, the manure pits were cleaned and manure was collected. In the 5th week of the collection period, air samples for odour and ammonia analyses, and manure samples were collected directly from each manure pit. Air samples were analysed for odour concentration and for hedonic value and intensity above odour detection threshold. Manure samples were analysed for volatile fatty acids, and indolic, phenolic and sulphurous compounds, ammonium and total nitrogen concentrations. Reducing dietary CP from 18% to 12% lowered odour emission ( P < 0.05) and ammonia emission ( P = 0.01) from pig manure by 80% and 53%, respectively. Reduced dietary CP decreased total nitrogen, methyl sulphide, carbon disulphide, ethanethiol, phenol, 4-ethyl phenol, indole and 3-methyl indole concentrations in the manure ( P < 0.05). Volatile fatty acids and cresols concentrations in the manure of pigs fed different dietary CP levels were similar. A reduction of dietary CP and at the same time providing essential AA is an option to reduce odour emission as well as ammonia emission from pig manure.

National survey of stress ulcer prophylaxis.

OBJECTIVE: To determine the rationale for using stress ulcer prophylaxis (SUP) among clinicians; to assess criteria used to define failure of SUP; and to evaluate the decision-making process in the selection of a prophylactic agent. DESIGN: A cross-sectional national mail survey. SETTING: Random sample of the members of the Society of Critical Care Medicine who identified anesthesiology, surgery, or internal medicine as their primary specialty area. PATIENTS: None. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: Questionnaires consisting of multiple-choice and short-answer questions were sent to a simple random sample of 1,268 physicians to assess the current practice of SUP. A total of 328 usable questions were returned, resulting in a response rate of 26%. All percentages reported in the results are based on the total number of responses. The risk factors for SUP that were most commonly identified were burns (91%), shock (90%), and sepsis (88%). These were also risk factors for which the respondents most commonly started SUP. Histamine-2-receptor (H2)-antagonists as a class, were the most commonly used prophylactic agents (67%). The most commonly used agents for SUP were ranitidine (31%), famotidine (24%), sucralfate (24%), and cimetidine (12%). Most respondents selected ranitidine for ease of administration, famotidine because of formulary availability, sucralfate for a better side effects profile, and cimetidine for cost-effectiveness. Eighty-two percent of respondents considered the presence of bright red blood in the nasogastric tube as failure of SUP. In cases where SUP failed, most respondents would add a second agent from a different therapeutic class. Of those respondents who used an H2-antagonist initially, 48% would add sucralfate, 36% would add antacid, and 13% would add omeprazole. Of those respondents who used sucralfate, 77% would add an H2-antagonist when SUP failed. For those respondents who would switch to another agent when the H2-antagonist failed, 52% would change to omeprazole, whereas 67% would change to an H2-antagonist when sucralfate failed. Only eight respondents would discontinue SUP when risk factors were resolved. Most respondents would discontinue SUP when the patient was no longer in the "nothing by mouth" status (28%), started on enteral feeding (23%), or discharged from the intensive care unit (21%). The mean duration of SUP was 6.3+/-4.5 (SD) days. CONCLUSIONS: This survey highlighted the lack of consensus in the use of SUP. Many patients receive SUP for an extended period, without clear-cut indications or documented benefit. The cost of unwarranted SUP in patients with low risk of stress ulcer gastrointestinal bleeding is prohibitive. Treatment algorithms or protocols for SUP based on prescribing patterns, hospital formulary restrictions, and cost-analysis should be considered for each institution to guide critical care physicians on the proper use of SUP therapies.

Clinical aspects of acute vs persistent diarrhea in Ho Chi Minh City, Vietnam.

A retrospective clinical study of acute and persistent diarrhea in children younger than three years of age was conducted for 12 months (October 1989 to September 1990) in a Pediatric Hospital in Ho Chi Minh City, South Vietnam. Most of the 3833 episodes of diarrhea identified were of short duration, with 77.7% lasting only 1-7 days. Only 5.3% of episodes lasted more than 14 days. Episodes of longer duration were associated with young age (0-5 months). Bloody stool was present in more than 40% of persistent episodes. Severe malnutrition was associated with persistent episodes that lasted 14-21 days (33%) or more than 22 days (59%). It is important that all patients with diarrhea have appropriate dietary management in addition to fluid therapy, and that future analysis examines etiologic factors to determine the optimal treatment of bloody diarrhea.