Dietary Crude Protein Research Articles

Effects of pre-partum dietary crude protein level on colostrum fat globule membrane proteins and the performance of Hu ewes and their offspring.

Dietary proteins play important roles in the growth and reproduction of sheep, and the ewe's demand for proteins increases dramatically during late pregnancy. This research aimed to investigate the effect of dietary crude protein (CP) levels during late pregnancy on colostrum fat globule membrane (MFGM) protein and the growth performance of Hu sheep and their offspring, and provide a reference for the protein intake of ewes during late pregnancy. A total of 108 multiparous Hu sheep (45.6 ± 1.18 kg) were selected for this study, then 60 pregnant ewes confirmed by B-scan ultrasonography were randomly divided into three treatments (20 ewes/treatment) and fed by total mixed ration pellet with CP levels at 9.00% (LP), 12.0% (MP), and 15.0% (HP) during late pregnancy, respectively. The weight and dry matter intake of ewes during late pregnancy were recorded to calculate the average daily gain (ADG) and feed conversion ratio (FCR). Twin lambs were weighed on days 0, 7, 14, 30, 60, and 180 after birth to calculate ADG. Meanwhile, the colostrum of ewes was collected within 12 h after delivery. The colostrum MFGM proteins were identified and quantified by the isobaric tag for relative and absolute quantification (iTRAQ) coupled with liquid chromatography-tandem mass spectrometry methods. In addition, biological functions of differentially expressed proteins (DEPs) were annotated by Gene Ontology annotation and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis. The results revealed that a 15.0% CP level had significant effects on the BW of lambs on days 0, 7, and 30 (P < 0.05). Notably, a total of 1,529 MFGM proteins were identified and 286 DEPs were found among three treatments. Functional analysis showed that DEPs were mainly involved in cell growth, differentiation, and tissue repair, and involved in metabolic pathways, such as the porphyrin and chlorophyll metabolism pathways. In this study, lambs in HP treatment had better growth performance; moreover, dietary 15.0% CP level also affected the colostrum MFGM proteins composition of Hu ewes. These observations can facilitate future studies on the feeding regimen of ewes during late pregnancy.

Interactive effects of high temperature and crude protein levels on growth performance, nitrogen excretion, and fecal characteristics of broilers.

In the present study, we aimed to explore the interactive effects of high temperature (HT) and dietary crude protein (CP) levels on nitrogen (N) excretion, fecal characteristics, and growth performance of broilers. A total of 288 broilers (Arbor Acres) were divided into six groups with eight replicates (six broilers per replicate). Two temperatures (ambient temperature: AT, 23°C; HT: 28 ~ 32 ~ 28°C) and three diets (CP: 14.90%, 18.18%, or 21.19%, with equal amounts of essential amino acids) were examined in a 2 × 3 factorial design. The experiment arrangement was from 4 to 6weeks of age. The results showed that HT led to a significant decrease in the N excretion (P < 0.0001), average daily feed intake (P < 0.0001), and weight gain of broilers (P < 0.0001), while it markedly increased the fecal pH (P = 0.015), fecal moisture (P = 0.0014), uric acid (UA) contents (P = 0.0018), and feed/gain ratio (P < 0.0001). A low CP diet significantly decreased the N excretion (P < 0.001), fecal pH (P = 0.016), fecal moisture (P < 0.0001), and UA contents (P < 0.0001), while it markedly increased the feed/gain ratio (P < 0.001). In conclusion, HT had a negative impact on the fecal characteristics and growth performance of broilers but showed positive effects on N excretion. Moreover, decreased CP levels had a positive effect on the N excretion and fecal characteristics in broilers.

Dietary metabolizable energy and crude protein levels affect pectoral muscle composition and gut microbiota in native growing chickens

The experiment aimed to study effects of dietary metabolizable energy (ME) and crude protein (CP) levels alone and in interaction on performance, pectoral muscle composition and gut microbiota in native growing chickens. A total of 648 10-wks-old Beijing-You Chicken (BYC) female chickens were randomly allocated to 9 groups with 6 replicates per group and 12 chickens per replicate, and the chickens were fed with a 3×3 factorial diets (3 levels of dietary ME: 11.31 MJ/kg, 11.51 MJ/kg, 11.71 MJ/kg; and 3 levels of dietary CP: 14%, 15%, 16%). The results showed that dietary ME and CP levels didn't affect average feed intake (AFI), body weight gain, feed gain ratio (P > 0.05), but ME level significantly affected the AFI (P < 0.05); mortality rate of 11.31 MJ/kg group was the highest (P < 0.05). Dietary ME, CP levels, and the interaction significantly affected pectoral CP and crude fat (CF) content of the growing chickens (P < 0.01). Dietary CP level had opposite effects on pectoral CP and CF content (P < 0.01). The 16% CP increased the pectoral CF content, which may have a negative impact on meat flavor. Dietary ME level affected 11 types of pectoral free amino acids (FAA) contents, including aspartic acid, L-threonine (P < 0.05), also amino acid classification, for example, total amino acid (TAA) and essential amino acid (EAA) content (P < 0.05). The 11.51 MJ/kg group had the highest TAA, EAA, delicious amino acid (DAA) content and EAA percentage (P < 0.05), while 11.31 MJ/kg group had the lowest bitter amino acid (BAA) content and BAA percentage and the highest fresh and sweet amino acid (FSAA) percentage (P < 0.05). Dietary CP level significantly affected glutamine and tyrosine content (P < 0.05). The interaction of dietary ME and CP level affected C20:3n6 content, saturated fatty acid (SFA), and unsaturated fatty acid (UFA) percentage (P < 0.05). The CP level significantly affected SFA percentage (P < 0.05). The 16% CP level increased the diversity of gut microbiota, but at the same time increased the relative abundance of Proteobacteria (P < 0.05), which is a sign of microbiota disorder. The increase of dietary ME level resulted in a gradual decrease in the diversity and relative abundance of gut microbiota. In conclusion, the present study suggested that the medium dietary ME (11.51 MJ/kg) and low CP (14-15%) levels can be helpful for enhancing pectoral muscle composition, increase meat quality such as flavor and nutritional value, and benefit for gut microbiota in native growing chickens.

Comparison of nano-capsulated thyme essential oils on intestinal microbial population and anti-oxidation status of broilers

This study was conducted to evaluate the effects of non and nano-capsulated thyme essential oils with saturated and unsaturated lipids (tallow and canola oil) and two levels of diet crude protein (standard and low than standard) on intestinal microbial population and anti-oxidation status of broilers. In this study, 384 Ross-308 broiler chickens in a factorial engagement of 2×2×2 (2 medicinal plant essential oils, two sources of vegetable oils, and 2 levels of diet crude protein) were used in a completely randomized design with 8 treatments, 4 replicates, and 12 bird in each replicate for 42 days. Experimental periods included starter (1-10 days), grower (11-24 days), and finisher (25-42 days). Canola oil significantly reduced the intestinal coliforms population. In contrast, tallow increased them (P&lt;0.05), a similar effect was observed with thyme forms, so the lowest coliform population blogged to the nano-capsulated form of thyme. In contrast, the highest coliform population resulted in non-capsulated thyme essential oil (P&lt;0.05). In an interaction between thyme essential oil form and diet crude protein level, the lowest coliform population was observed with diet contained nano-capsulated thyme essential oil and low level of diet crude protein (P&lt;0.05). Regarding antioxidant status, reducing the diet crude protein increased MDA and GPX (P&lt;0.05). In an interaction between diet crude protein and thyme form, a diet with low crude protein and capsulated thyme increased the level of SOD (P&lt;0.05). In general, results of the current experiment indicated that in Ross-308, broiler chickens using capsulated thyme essential oil with canola oil and low crude protein improves intestine microbial population and antioxidant status of broilers.

Evaluation of nutritional quality for weaner piglets of a new methanotrophic microbial cell-derived protein feed

This study aimed to test the hypothesis that a new methanotrophic microbial cell protein (MCP) product, Uniprotein®, has a protein value comparable to other high-quality feeds for weaner piglets. Two experiments were conducted. Experiment 1 was a balanced 6 × 6 Latin square design experiment with six ileal cannulated castrated pigs (start weight 30.2 ± 1.4 kg). They were fed six different diets (one diet did not belong to this study) over six periods, each of one week duration. Four of the diets contained 180 g crude protein (CP)/kg as-fed with either MCP, potato protein (PP), fishmeal (FM), or soy protein concentrate as the sole N-source. The fifth diet was N-free. Experiment 2 was a dose-response trial, where piglets during the first 14 days post-weaning were fed diets including increasing amounts of MCP (0, 30.0, 60.0, or 100.0 g MCP/kg as-fed, equivalent to 0, 112, 221 and 359 g microbial-derived CP/kg diet CP) at the expense of FM and PP. Crystaline CP, Lys, Met, Thr, Trp and Val were added to minimize differences across diets, and no medicinal zinc was added to any of the diets. In experiment 1, MCP had the second highest content of essential amino acids (EAA), but the lowest coefficient of standardized ileal digestibility for all EAA except Lys (P < 0.001). However, when contents of ileal digestible EAA were expressed relative to contents of ileal digestible Lys, MCP complied with Danish nutrient recommendations for weaner piglets for 7 out of 9 EAA, and with particularly high levels of digestible Met and Trp. Microbial cell protein had a superior profile as compared to FM for digestible EAA relative to digestible Lys. In experiment 2, MCP could constitute up to 221 g CP/kg diet without any addition of medicinal zinc during the first 14 days post-weaning without any negative impacts on daily weight gain or feed efficiency (gain:feed) compared to the control diet (0 MCP). In conclusion, MCP fulfills Danish recommendations for EAA composition for most EAA and can replace other high quality protein sources to constitute up to 22% of diet CP for weaner piglets without compromising piglet performance.

Acidified diet is not effective in preventing hypocalcemia in dairy cows on French commercial farms

The objective of this study was to assess, in the context of typical dairy farms in western France, the preventive effects of prepartum diet acidification (AcD) and mineral intake during late gestation on the incidence of subclinical hypocalcemia (SHC) and subclinical hypophosphatemia (SHP) after calving. We conducted a longitudinal study that followed a cohort of 371 Holstein cows from 26 French dairy farms; of these, 235 cows (15 farms) were supplied with anionic salts during late gestation, and 136 cows (11 farms) were not. Blood samples were collected from 1 to 22 cows per farm (average of 14.3 cows per farm) between 24 and 48 h after calving. Total calcium and inorganic phosphorus concentrations in plasma were then quantified by inductively coupled plasma - optical emission spectrometry. The effects of AcD on the incidence of SHC and SHP were assessed using mixed linear models that evaluated the cow-level factors parity, milk yield index, and individual health events/treatments, and the farm-level factors diet calcium and magnesium content, dietary phosphorus intake, vitamin D supply, diet crude protein content, and duration of AcD, with farm as a random effect. Approximately 55% of cows were diagnosed with SHC (calcium &amp;lt; 2.0 mmol/l, n = 203) and 37% with SHP (inorganic phosphorus &amp;lt; 1.3 mmol/l, n=136). The first model confirmed earlier findings that the risk of SHC is higher with increased parity (P ≤ 0.0001) and revealed a higher risk associated with high milk yield (P = 0.0005), high phosphorus intake (40–60 g/cow per day, OR = 3.5; ≥ 60 g/cow per day, OR = 7.3; P = 0.0003) and high vitamin D supply (≥ 19950 IU/cow per day, OR = 3, P = 0.007). The second model highlighted a greater risk of SHP with increasing parity (P = 0.03) and showed trends for the preventive effects of AcD (OR = 0.4, P = 0.07) and moderate amounts of phosphorus in the diet (OR = 0.4, P = 0.10). Overall, our results do not support the effectiveness of AcD in preventing SHC or SHP under field conditions examined here, probably resulting from insufficient diet acidification.

Effect of proportion and digestibility of grass-clover silage on feed intake, milk yield, and nitrogen excretion in lactating dairy cows

The aim of the current study was to examine the effect of proportion and digestibility of grass-clover silage on dry matter intake (DMI), milk yield and nitrogen (N) excretion in lactating dairy cows. In total, 36 Danish Holstein dairy cows, 12 primiparous and 24 multiparous, were included in the study. At the beginning of the experiment the cows were on average (mean ± SD) 122 ± 81 days in milk (DIM). The cows were divided into 9 groups (4 cows in each group) based on parity and DIM, and were randomly assigned to one of four dietary treatments in a 4 x 4 Latin square design with 9 replications. The four dietary treatments differed in forage source as follows: 1) low proportion of low digestible grass-clover silage; 2) low proportion of high digestible grass-clover silage; 3) high proportion of low digestible grass-clover silage; 4) high proportion of high digestible grass-clover silage. Different proportions were obtained by exchanging grass-clover silage with maize silage (30:70 or 70:30 on DM basis). Different digestibilities of grass-clover silages were obtained by using two grass-clover silages differing in harvest time, spring growth and first re-growth, with these expected to have a high and low digestibility, respectively. The experiment was divided into 4 periods, all lasting for 3 weeks of which the first 17 d were used as adaption and the last 4 d were used for sampling and recording. Feed and water intake as well as milk yield were recorded daily, and milk samples were collected for determination of milk composition. In addition, faeces and blood samples were collected for chemical analyses. Replacing grass-clover silage with maize silage increased DMI and milk protein but reduced milk fat, whereas increased digestibility of grass-clover silage decreased DMI but increased milk protein. Milk yields (kg and kg of energy-corrected milk (ECM)) were not affected by diet, probably due to the increase in DMI observed in cows offered low digestible grass-clover. Excretion of N in urine increased with high proportion and low digestibility of grass-clover silage, probably a result of the greater crude protein (CP) concentration in grass-clover silages than in maize silage, and in low compared to high digestible grass-clover silage, respectively. Thus, proportion and digestibility of grass-clover silage surprisingly seemed to have only minor effect on milk production and composition. However, digestibility was confounded with the harvest used, and the different cuts of grass-clover silage likely differed in clover proportion, which could have affected the results. Finally, urinary N excretion increased with increased dietary CP concentration.

Association of virginiamycin and multiple supplement for cattle fed a high-quality tropical forage

The aim of this study was to evaluate the effect of adding virginiamycin to either mineral mixture or multiple supplement on intake, digestion, ruminal fermentation profile, rumen microbial production, blood metabolites, and liver metabolism of zebu heifers fed a high-quality tropical forage. Eight Brahman heifers were assigned to a replicated 4 × 4 Latin Square design. The treatments were: mineral mixture, mineral mixture with virginiamycin, multiple supplement, and multiple supplement with virginiamycin. The basal diet consisted of a high-quality Tifton 85 hay (Cynodom sp.) chopped at 10-cm particle size and fed twice daily. The mineral mixture was provided daily at 120 g/animal. The multiple supplement was formulated to provide 300 g of crude protein (CP)/kg as fed, contained mineral mixture, corn grain, and urea: ammonium sulfate, and was daily provided at 200 g/animal. The mineral mixture and multiple supplement provided the same daily amount of minerals. The amount of supplemental virginiamycin was based on a maximum theoretical response on animal performance (50 mg/100 kg body weight) and daily mixed to the supplements types. The treatments were compared according to a 2 × 2 factorial arrangement (mineral mixture and multiple supplement, with or without virginiamycin). The virginiamycin supplementation did not alter either voluntary intake or digestibility (P≥0.44). Using the multiple supplement decreased forage (P&amp;lt;0.05) and digested organic matter (DOM, P&amp;lt;0.10) intake, but increased dietary CP : DOM ratio (P&amp;lt;0.01). The multiple supplement increased the ruminal ammonia concentration (P&amp;lt;0.04) and the acetate-to-propionate ratio (P&amp;lt;0.06). Virginiamycin increased urinary nitrogen (N) when provided along with multiple supplement (P&amp;lt;0.05). Fecal N was decreased by multiple supplement (P&amp;lt;0.06). Despite these effects, no effect was verified on either body N accretion (P≥0.48) or microbial N production in the rumen (P≥0.27). Virginiamycin decreased the blood IGF-1 (P&amp;lt;0.07). The hepatic gene expression for propionyl-CoA carboxylase was increased by virginiamycin (P&amp;lt;0.01). Virginiamycin increased the hepatic gene expression of both citrate synthase and pyrivate carboxylase when mineral mixture was provided (P&amp;lt;0.01), but decreased it when animals were fed multiple supplement (P&amp;lt;0.04). Using a low-intake multiple supplement with a high CP content for cattle fed high-quality forage causes a substitutive effect on forage intake, but keeps nitrogen accretion unchanged. That pattern indicates an improvement in feed efficiency. On the other hand, virginiamycin supplementation seems to cause some post-prandial influences, which may vary according to the type of supplement. Those influences apparently improve animal efficiency.

Effects of adding graded levels ofAchyranthes japonicaroot extract to low crude protein diet on growth performance, nutrient digestibility, fecal microbiota, and meat quality parameters in broilers

This study was conducted to investigate the effect of Achyranthes japonica root extract (AJE) added to a low-protein diet on broiler growth performance, nutrient utilization, cecal microbiota, and meat quality parameters. A total of 450 Ross 308 broilers were randomly assigned to one of five dietary treatments. The dietary treatments were standard crude protein (SCP) diet, low crude protein (LCP) diet, and LCP diet supplemented with 0.02, 0.04, and 0.06% AJE. Here, the SCP and LCP diets were 21.50% and 21.07% CP during days 8–21 and 20.00% and 19.40% CP during days 22–35, respectively. The LCP diet tended to decrease total body weight gain (TBWG) compared with the SCP diet. Increasing levels of AJE inclusion linearly increased ( P &lt; 0.05) TBWG and the LCP diet supplemented with AJE also increased ( P &lt; 0.05) TBWG compared with the LCP diet, whereas feed intake and feed conversion ratio were unaffected. AJE supplementation to the LCP diet tended to increase energy digestibility compared with the LCP diet. Breast muscle weight tended to increase by a graded level of AJE supplementation. In conclusion, AJE supplementation represented a potential ability to maintain a similar growth performance when added to a low-protein diet by enhancing nitrogen digestibility and meat quality in broilers.

Effects of corn distillers grains with yeast bodies and manipulation of dietary cation and anion difference on production, nutrient digestibility, and gas emissions from manure in lactating cows.

In a randomized complete block design, 40 lactating Holstein cows (average 98 d in milk and 41 kg/d of milk yield) were randomly assigned to 1 of 4 diets: (1) containing soybean meal as the major protein supplement (CON diet); (2) CON diet with high-protein dried corn distillers grains at 20% on a dry matter (DM) basis by replacing mainly soybean meal (DG diet); (3) DG diet except that high-protein dried corn distillers grains with yeast bodies (extracted after corn ethanol production) was used (DGY diet); or (4) DG diet supplemented with sodium bicarbonate and potassium carbonate to elevate the dietary cation and anion difference (DCAD; DG-DCAD diet). The DCAD of CON, DG, DGY, and DG-DCAD were 185, 62, 67, and 187 mEq/kg of DM, respectively. The experiment began with a 10-d covariate period and then cows were fed the experimental diets for 5 wk (2-wk diet adaptation and 3-wk data collection periods). Dry matter intake and milk yield were measured daily, and spot urine and fecal samples were collected in the last week of the experiment to measure nutrient digestibility; N, S, and P utilization and excretion; and in vitro NH3 and H2S emissions from manure. All data were analyzed using the MIXED procedure of SAS (random effect: block; fixed effects: diets, repeated week, and interactions). During data collection, DM intake was not different among treatment groups, but milk yield tended to be lower (42.4 vs. 39.9 kg/d) for DG, DGY, and DG-DCAD versus CON, which could have been caused by decreases in organic matter and neutral detergent fiber digestibility. Milk protein yield tended to be lower (1.33 vs. 1.24 kg/d) for DG, DGY, and DG-DCAD versus CON. Milk fat yield was lower (1.26 vs. 1.55 kg/d) for DG and DGY versus CON, but that for DG-DCAD (1.43 kg/d) did not differ from CON. Similarly, energy-corrected milk was lower (38.0 vs. 43.3 kg/d) for cows on DG and DGY versus those on CON, but it did not differ between DG-DCAD (40.7 kg/d) and CON. Urinary and fecal N excretion were greater for DG, DGY, and DG-DCAD compared with CON due to greater dietary crude protein content and N intake. However, NH3 emissions did not differ across treatments. Intakes of dietary P and S were greater for DG, DGY, and DG-DCAD, resulting in greater excretion of those in manure and greater H2S emissions from manure compared with CON. These data suggest that the negative effects of feeding distillers grains on production of lactating cows can be partly explained by a decrease in nutrient digestibility (milk yield) and excessive anion load (milk fat). The milk fat response to DG-DCAD suggests that milk fat depression observed with a diet with high content of distillers grains can be partially alleviated by supplementation of cations. In the current study, we observed no beneficial effects of DG containing yeast bodies.

Effect of dietary crude protein and rearing conditions on environmental footprint of Ross 308 broiler

Effect of dietary crude protein and rearing conditions on environmental footprint of Ross 308 broiler

Reducing dietary crude protein in broiler diets does not compromise performance and reduces environmental impacts, independently from the amino acid density of the diet

The objective of the present experiment was to investigate the influence of dietary CP, standardized ileal digestible ( SID) Lys level and their interaction in male Ross 308 broilers. From day 10, six experimental treatments were tested until day 35. The six experimental treatments consisted in a 3 × 2 factorial design with 3 levels of dietary SID Lys/CP (equaivalent to 3 levels of dietary CP) and 2 levels of dietary SID Lys. Growth performance, uniformity, carcass traits, litter quality, blood & gut parameters, nitrogen ( N ) emissions and global warming potential ( GWP ) were measured or calculated. There was no interaction for all criteria except for NH 3 and N 2 O volatilization. The increase of dietary SID Lys/CP did not affect growth performance or uniformity, increased abdominal fat yield, decreased all N related parameters (litter N, blood uric acid, N excretion, NH 3 and N 2 0 volatilization). There was an interaction between dietary CP and AA origin for GWP; GWP was further reduced after CP reduction when using AA from EU. Increasing SID Lys improved growth performance, increased uniformity, increased breast meat yield, reduced abdominal fat yield, but increased N emissions and GWP. This study indicates that dietary CP can be drastically reduced in different nutritional contexts without negatively affecting growth performance, and with positive benefits on the environment.

The Environmental Impact of Lowering Dietary Crude Protein in Finishing Pig Diets—The Effect on Ammonia, Odour and Slurry Production

Excess nitrogen excretion, ammonia and odour are environmental pollutants associated with pig production. Reducing dietary crude protein (CP) will lower the amount of nitrogen excreted, reducing the potential for ammonia emissions, if diets are adequately formulated to supply amino acids and production performance is maintained. Crude protein content in diets for finishing pigs has been lowered recently, but the quantitative effect of this reduction on ammonia, odour, and slurry output is not well-established. The relationship between ammonia and odour is equivocal, and the effect on slurry production is unclear. The objective of this study was to investigate the effect of lowering dietary CP on ammonia emission, odour emission and slurry output of finishing pigs. Thirty entire boar pigs were individually housed in groups of six, from 10 weeks of age (30 ± 3.0 kg) and offered standard diets. At 75 kg (±1.5 kg) pigs were assigned to one of three treatment diets; (1) 180 g/kg CP, 11.0 g/kg total lysine (High CP), (2) 150 g/kg CP, 11.1 g/kg total lysine (Medium CP), and (3) 130 g/kg CP, 9.0 g/kg total lysine (Low CP). After three weeks on the experimental diets pigs were moved, six each week, to individual calorimetry chambers to measure ammonia and odour emissions. Pigs were offered treatment diets ad libitum. At the end of the recording period, the pigs were removed from the chamber, weighed and feed disappearance recorded to calculate intake. The slurry in each chamber was collected and analysed. The reduction in CP in the diet from 180 g/kg to 150 g/kg resulted in a 22% reduction in ammonia emissions, and from 180 g/kg to 130 g/kg resulted in a 47% reduction (p &lt; 0.001). Slurry output from pigs offered the 130 g/kg CP diet was reduced by 39% (p &lt; 0.001) and dry matter increased by 35% compared to slurry from pigs offered the 180 g/kg CP diet (p &lt; 0.05). Water usage (p = 0.017), slurry output and nitrogen and phosphate in the slurry (p &lt; 0.05, respectively) were found to decrease linearly with decreasing dietary CP content. There was no significant effect of reducing CP on performance or odour emission but hydrogen sulphide emissions decreased linearly (p &lt; 0.010) with decreasing dietary CP. There was a weak positive relationship between odour emission and ammonia (linear: R2 = 0.25, p = 0.005) with odour emission reduced as ammonia emission reduced. Reducing dietary CP in finishing pig diets could reduce ammonia emissions, water usage and slurry and nutrient output from pig production.

PSX-A-4 Effects of Dietary Protein Content and Crystalline Amino Acid Supplementation Patterns on Intestinal Bacteria and Their Metabolites in Weaned Pigs Raised Under Different Sanitary Conditions

Abstract The objective of this experiment was to investigate the effects of dietary crude protein (CP) content and crystalline amino acids (CAA) supplementation patterns on the bacteria and their metabolites in the intestine of weaned pigs raised under clean (CSC) or unclean sanitary conditions (USC). One hundred forty-four piglets (6.35 ± 0.63 kg BW) were assigned to 1 of 3 diets to give 8 replicates, each with 3 pigs, over a 21-days period. Diets consisted of a high CP (HCP; 21%) and two low CP (LCP; 18%) diets supplemented with all 10 essential AA as CAA or only 6 CAA (Lys, Met, Thr, Trp, Val, and Ile). The CSC room was washed weekly, whereas the USC room had sow manure spread in the pens and was not washed throughout the experiment. Digesta from jejunum and colon were analyzed for ammonia N, short-chain fatty acids, and biogenic amines, but only colonic digesta was analyzed for microbiome composition (16s rRNA sequencing on MiSeq). Data were analyzed using R software for 16S rRNA and the MIXED procedure of SAS for microbial metabolites. Sanitation, CP content, and CAA supplementation patterns did not affect colonic bacterial composition or diversity in weaned pigs. Pigs raised under USC had greater (P &amp;lt; 0.05) jejunal ammonia N than those under CSC. Pigs fed LCP diets had reduced (P &amp;lt; 0.05) jejunal ammonia N compared to those fed HCP diet. No difference was found in colonic ammonia N. Interactions between sanitation and dietary CP content were observed (P &amp;lt; 0.05) for jejunal acetate and colonic spermidine and spermine. In conclusion, reducing dietary CP lowered ammonia N content regardless of the sanitation and increased microbial metabolites in weaned pigs raised under USC. However, colonic bacterial composition and diversity were not influenced by dietary CP, sanitary conditions, or CAA supplementation patterns.

242 The Impact of Feed Formulation and Feeding Methods on Pig and Poultry Production on the Environment

Abstract Dietary energy and nutrient losses associated with its conversion into animal products increase production costs and contribute to the environmental footprint of farms with the excessive application of nitrogen, phosphorus, or trace minerals from manure or carbon and methane losses. Formulating diets with the appropriate levels of minerals and amino acids can help improve dietary protein and energy efficiency and reduce nutrient losses. For example, an 8% reduction in dietary crude protein in pig feeds is estimated to increase nitrogen efficiency by more than 50%, while costing 11% less than a control diet without industrial amino acids. This reduction in protein intake also increases energy availability due to reduced energy losses associated with protein deamination. Urinary and intestinal fermentation energy losses can be 24% lower for pigs fed low-protein diets compared to control diets. Nonetheless, determining the optimal level of dietary amino acid remains a difficult challenge in conventional phase feeding systems. Therefore, group or individual precision feeding is another powerful tool to increase nutrient efficiency. By feeding individual growing-finishing pigs with diets tailored to their requirements, precision feeding can decrease nitrogen excretion by 30% and greenhouse gas emissions by 22% compared to conventional 3-phase feeding. The benefits of feeding pigs with low-protein diets and precision feeding techniques are additive and might result in a 61% protein efficiency of utilization. The formulation of very-low-protein diets and the implementation of precision feeding techniques rely on sound nutritional concepts and comprehensive biological models developed to precisely estimate individual real-time nutrient requirements and animal responses. Understanding the metabolic processes responsible for the observed variation between individual animals in their ability to utilize dietary nutrients is challenging, but there is a need to further improve nutrient efficiency and reduce the environmental impact of livestock production systems.

PSXVI-11 Effects of Yucca Schidigera Extract and Multi-Carbohydrase in Different Crude Protein Diets on Growth Performance, Nutrient Digestibility, Carcass Parameters and Noxious gas Emission in Broilers

Abstract The scarcity of feed raw materials with a consequential increase in the price of animal feed has attracted the attention of nutritionists to find a viable option to address this issue. The inclusion of plant extract and enzyme to the energy- and protein-reduced diet could be a viable strategy that would contribute to reducing the feed cost. Therefore, the purpose of this study was to determine how different crude protein diets with Yucca schidigera extract and multi-carbohydrase could impact broiler growth performance, nutrient digestibility, carcass metrics, and noxious gas concentrations in the excreta. A total of 480 one-day (d)-old broilers (ROSS 308), with initial body weight (BW) of 45.2 ± 0.3 g were randomly assigned into four (4) dietary treatments, each with six replication cages and 20 birds per cage. In phase I (starter), broiler were fed with diets containing T1 (CP 21%, ME 2,969 Mcal/kg); T2 (CP 19%, ME 2,863 Mcal/kg + 0.02% Yucca); T3 (CP 17%, ME 2,865 Mcal/kg + 0.02% Yucca); and T4 (CP 17%, ME 2,861 Mcal/kg + 0.02% Yucca + 0.1% α-1, 6-galactosidase and β-1,4-mannanase). During phase II (grower) diets contained T1 (CP 19%, ME 3,086 Mcal/kg); T2 (CP 17%, ME 2,977 Mcal/kg + 0.02% Yucca); T3 (CP 15%, ME 2,978 Mcal/kg + 0.02% Yucca); and T4 (CP 15%, ME 2,978 Mcal/kg + 0.02% Yucca + 0.1% α-1,6-galactosidase and β-1,4-mannanase multi-carbohydrase). The addition of Yucca extract and multi-carbohydrase to the low CP diets revealed a positive result on the growth performance, nutrient digestibility, carcass parameters, and noxious gas emission. Overall, broilers supplemented with Yucca schidigera extract 0.02% and α-1,6-galactosidase and β-1,4-mannanase multi-carbohydrase (0.1%) demonstrated the best production performances compared with the other treatment groups. Thus, a combination of Yucca schidigera and multi-carbohydrase could to be added to the diets with low CP to boost broiler production performance.

167 Monomodular and Multi-Functional Processive Endocellulases for Improving Fibre Utilization and Reducing Environmental Footprint in Pigs

Abstract Global emission of the major greenhouse gases (GHG) from food animal production accounts for 15% of the total human-induced GHG with pork production being a significant contributor. Poor efficiency of dietary fibre utilization not only limits global pork production profit margins but also adversely affects dietary crude protein and amino acid utilization; and these collectively lead to excessive manure fibre and nitrogenous compounds, resulting in anaerobic biogenesis and emission of the major GHG from swine manure slurry storage. Two unique glycosyl hydrolase family-5 (GH5) processive endoglucanases, referred to as GH5-tCel5A1 and GH5-, have been reported. The GH5-tCel5A1 was originally identified via targeted genome sequencing of the extremely thermophilic Thermotoga maritima while the GH5-p4818Cel5_2A was screened from the porcine hindgut microbial metagenomic expression library. Both GH5-tCel5A1 and GH5-p4818_2A have been characterized to be monomodular, act as processive β-1,4-endoglucanases and have multi-functionality towards hydrolyzing dietary natural crystalline cellulose and pre-treated cellulosic substrates as well as several hemicelluloses including β-glucans, xylan, xylogulcans, mannans, galactomannans and glucomannans. We have recently overexpressed both GH5-tCel5A1 and GH5-p4818Cel5_2A in the ClearColiBL21(DE3) cell and investigated the susceptibility of both these cellulases to auto-oxidation by air-borne O2. Furthermore, we have also examined these endoglucanases’ stability under the mimicked in vitro porcine gastric and the small intestinal pH and proteases’ conditions. Further pig nutrition and growth performance studies are being conducted to investigate the in vivo efficacy of these two processive endoglucanases as newly emerging potential exogenous fibre enzymes.

PSX-A-2 Effects of Dietary Crude Protein Level and Corn Grain Processing on Whole-Body Urea Kinetics and in-Vitro Urea Secretion Into the Rumen of Sheep

Abstract In ruminants, urea-N salvaging allows secretion of endogenously-produced urea (UER) into the rumen, where it can provide N for microbial growth. Our objective was to determine the effects of dietary crude protein content and corn grain processing on whole-body urea kinetics and in vitro serosal-to-mucosal urea flux (Jsm-urea) across ruminal epithelia. Thirty-two Rideau-Arcott ram lambs were blocked by BW into groups of 4 and then randomly allocated within block to one of 4 dietary treatments (n = 8) in a 2 × 2 factorial design. Dietary factors were crude protein content (10.9% [LP] vs. 15.8% [HP]) and corn grain processing (whole-shelled [WSC] vs. steam-flaked [SFC]). Feeding SFC was expected to provide more ruminally-fermentable energy than WSC. Four blocks of animals (n = 4) were used in 4-d continuous infusions of 15N-15N with concurrent collections of urine and feces to determine whole-body urea kinetics. After 23 d of dietary exposure, lambs were killed to collect ruminal epithelia which were mounted in Ussing chambers to determine Jsm-urea. Lambs fed HP had greater N intake (P = 0.01) and total N excretion (P = 0.002) than those fed LP; however, retained N (g/d or % of N intake) was similar between the 2 groups. When expressed as absolute amounts, urea-N secreted into the gut (GER) and urea-N used for anabolic purposes (UUA) were similar across diets; however, lambs fed the LP diet had a greater GER/UER ratio (P = 0.02) and tended to have a greater UUA/GER ratio (P = 0.05) than lambs fed the HP diet. Diet had no effect on ruminal Jsm-urea. Grain processing had no effects on GER, UUA and Jsm-urea. These results suggest ruminants fed protein-restricted diets have a greater dependence on urea secretion into the gut to provide N for anabolic use.

PSIII-A-17 Relationships between Diet Quality and Serum Metabolic Indicators in Prenatally Stressed Growing Bos Indicus Heifers

Abstract Our research group has previously reported on grazing behavior, diet selection, and weight change in prenatally stressed and translocated Brahman heifers grazing native rangeland. Our current objective was to evaluate relationships between diet quality and metabolic indicators. Twelve yearling heifers were transported ~700 km from Overton, TX to Sonora, TX. Six heifers (283±10 kg) were born to dams subjected to transportation stress during mid-gestation (PNS) and 6 (279±17 kg) were born to non-stressed dams (CON). Heifers grazed a series of 24-ha native range pastures and were sampled (BW, BCS score, blood, and feces) at 2-wk intervals from May through September. Fecal samples collected from the ground or the rectum of each animal were stored at -20o C until processed for near infrared reflectance spectroscopy prediction of diet crude protein (CP) and digestible organic matter (DOM). Blood was obtained via coccygeal venipuncture and processed to yield serum. Serum analyses were obtained from the Texas A&amp;M Veterinary Medical Diagnostic Laboratory. Relationships between constituents of interest were determined by linear regression. Significance was considered to be P &amp;lt; 0.05. Blood urea nitrogen (BUN; mg/dL) was greater (P = 0.04) in PNS (8.39±0.32) than CON (7.39±0.33). Positive correlations were found between CP and BUN (RSQ = 0.76, SE = 1.25 mg/dL; P &amp;lt; 0.001), albumin (RSQ = 0.57, SE = 0.06 mg/dL; P &amp;lt; 0.01), and average daily gain (RSQ = 0.63, SE = 0.47 kg; P &amp;lt; 0.01). Similar relationships were observed between DOM and glucose (RSQ = 0.64, SE = 3.91 mg/dL; P &amp;lt; 0.01), cholesterol (RSQ = 0.37, SE = 5.47 mg/dL; P &amp;lt; 0.05), and average daily gain (RSQ = 0.47, SE = 0.56 kg; P &amp;lt; 0.01). PNS affected circulating nitrogen concentration. Diet quality was related to weight gain and serum indicators of nutritional status.

Juice from silage in green bio refineries – a potential feed ingredient in liquid diets to weaned pigs

ABSTRACT The objective of this study was to evaluate silage juice from green bio refineries in liquid diets to pigs and its’ effect on growth, cleanliness and health. Ninety-six (L × Y) × H organically raised pigs were fed either a control diet (C-diet) or a silage feed juice diet (SFJ-diet). The C-diet consisted of a commercial feed mixed with water prior to feeding. The SFJ-diet consisted of a lower ration of commercial feed mixed with silage feed juice (SFJ) instead of water, theoretically replacing 10% of the dietary crude protein content. All pigs consumed the juice and grew similarly, on average 0.48 kg/day. SFJ pigs were significantly dirtier on their back and head than C pigs (P < 0.001 for all), but cleanliness in the rectum area and in the pen did not differ. Silage juice had only minor effects on hygienic measures and could be a potential local feed ingredient to pigs.