Total Fecal Output Research Articles

Assessment of the Potential Mechanisms of Anti-diarrhoeal Activities of Ethanol Extract of Monoon longifolium Leave in Wistar Rat

Background: Numerous diseases related to diarrhea are the primary cause of morbidity and mortality in underdeveloped countries, accounting for hundreds of thousands of deaths annually. Polyalthia longifolia, the false ashoka, commonly referred to as Monoon longifolium is a tree species from Asia. It is commonly found in southern india, Sri Lanka and Nigeria. Polyalthia longifolia has been utilized for decades to treat an extensive variety of illnesses, including diarrhea. Method: The plant was extracted with ethanol using cold maceration. Preliminary qualitative and quantitative phytochemical screening of ethanol extract of Polyalthia longifolia leaf was conducted using the techniquees of Harbone (1998); Trease and Evans (1978). The Lorke (1983) approach was used to calculate the Median Lethal Dose (LD50). Diarrhea caused by castor oil was produced using the Awouter et al., 1973 method. The testing for gastrointestinal transit was conducted using the Mascolo et al. (1996) technique. The Tietz (1994) method was used to conduct the electrolyte levels assay. The assay for kidney function indicators was conducted using Bartels and Bohmer's (1972) methodology. Results: The results of phytochemical screening showed that alkaloids and tannins occurred in high concentration, flavonoids and steroids occurred in moderate concentration, whereas terpenoids, glycosides and phenolic acid occurred in lowest concentration. The acute toxicity study revealed that the plant extract was not toxic even at the dose of 5000 mg/kg. Groups treated with 200,400, and 600 mg/kg b.w of extract showed significant (P < 0.05) inhibition in the frequency of defecation of wet feces and total fecal output compared with positive control. Similarly, Groups treated with 200, 400, and 600 mg/kg body weight of extract demonstrated significant (P < 0.05) antimotility activity when compared with the positive control. However, groups treated with 200,400 and 600mg/kg body weight showed a significant (P < 0.05) increase in chlorine and sodium with corresponding decrease in bicarbonate and potassium level when compared with the positive control. The results from kidney function markers showed that groups treated with 200, 400 and 600 mg/kg b.w in a dose dependent manner showed a significant (p < 0.05) reduction in creatine and urea when compared with positive control. Conclusion: The ethanol leaf extract of Polyalthia longifolia has considerable antidiarrheal activity on castor oil-induced diarrhea and gastrointestinal motility models, confirming the reason for its wide use in traditional treatment of diarrheal conditions.

270 Zinc from Methionine Hydroxy Analog Chelate Is More Effective in Enriching Tissues Than Zinc from an Amino Acid Complex in Growing Pigs Using Stable Isotopes

Abstract An adequate supply of Zn should effectively reach tissues to support fundamental physiological functions. This study compared tissue enrichment using stable Zn isotopes when fed as methionine hydroxy analog chelate (Zn-MHAC [Novus International Inc., St. Charles, MO]) or an amino acid complex (Zn-AAC) in growing pigs. Twenty gilts (31.5 ± 2.8 kg BW) were individually housed and fed a common diet (corn-soy-based with phytase) with 26 mg/kg of Zn from ingredients and 15 mg/kg supplemented as Zn sulfate. At d 28, pigs were surgically catheterized in the jugular vein and moved to metabolism crates. After 2 d of recovery, 16 pigs were randomly selected to receive an oral bolus containing 1 of 2 doses (8 or 12 mg) of Zn67 in the form of Zn-AAC (8 or 12 mg) and Zn70 in the form of Zn-MHAC. The remaining 4 pigs received a placebo bolus and served as controls. Blood samples were collected periodically between -15 and 1,440 min relative to bolus. Total urine and fecal output were collected at 0, 6, 12, and 24 h relative to bolus. All pigs were euthanized 24 h after bolus to harvest tissues. Zinc isotope enrichment was calculated from analyzed samples as the difference of Zn67 and Zn70 portions between control and isotope-bolused pigs. Data were analyzed as a 2×2 factorial (mineral source×dose) using PROC MIXED procedure of SAS. No interactions between trace mineral source and isotope dose for any tested variables were observed. Gastrointestinal and central metabolism tissues, including stomach, duodenum, jejunum, ileum, pancreas, liver, and kidney, demonstrated greater enrichment from Zn-MHAC than Zn-AAC (P ≤ 0.001). In reproductive tissues, ovary showed similar Zn enrichment between Zn-MHAC and Zn-ACC (P = 0.841). However, there was greater enrichment from Zn-MHAC than Zn-AAC in the uterus (P = 0.002). For musculoskeletal tissues, despite a numerical increase for Zn-MHAC compared with Zn-AAC, there was no significant difference of Zn source on enrichment of metacarpal bones (P = 0.190). The hoof matrix tended to have greater enrichment from Zn-MHAC than Zn-AAC (P = 0.097). There were no differences between trace mineral sources on enrichment of Zn in the muscle (P = 0.839). Immune tissues, including thymus (P < 0.001) and spleen (P = 0.017), demonstrated greater enrichment from Zn-MHAC than Zn-AAC. Despite a numerical increase with Zn-MHAC, plasma area under the curve (AUC) was not significantly different between Zn-MHAC and Zn-AAC (P = 0.467). Similarly, despite a numerical increase, the higher dose of Zn isotope did not significantly increase (P > 0.050) enrichment in gastrointestinal, central metabolic, reproductive, musculoskeletal (except for muscle: P = 0.042), immune tissues, or plasma AUC. There were no differences in Zn AUC (0-24h; P > 0.100) enrichment between trace mineral source and dose in feces and urine. In conclusion, Zn-MHAC delivered more Zn to physiologically important tissues that support productivity and health of pigs than Zn-AAC.

A randomized dietary intervention to increase colonic and peripheral blood SCFAs modulates the blood B- and T-cell compartments in healthy humans

SCFAs have immune-modulating effects in animal models of disease. However, there is limited evidence that this may occur in humans. This study aimed to determine the effects of increased exposure to SCFAs via dietary manipulation on colonic fermentation and adaptive immune cells. Twenty healthy young adults (18-45 y of age) underwent a blinded randomized crossover dietary intervention, consuming a high-SCFA diet and a matched low-SCFA diet for 21-d with a 21-d washout in between. SCFAs were provided through resistant starch, inulin, and apple cider vinegar. Blood and 3-d total fecal output were collected at baseline and at the end of each diet. GC was used to measure fecal and plasma SCFA. Flow cytometry was used for peripheral blood immunophenotyping. According to a paired samples Wilcoxon test, the high-SCFA diet was associated with significantly higher fecal SCFA concentrations [median (IQR); 86.6 (59.0) compared with 75.4 (56.2) µmol/g, P = 0.02] and lower fecal ammonia concentrations [26.2 (14.7) compared with 33.4 (18.5) µmol/g, P = 0.04] than the low-SCFA diet. Plasma propionate [9.87 (12.3) compared with 4.72 (7.6) µmol/L, P = 0.049] and butyrate [2.85 (1.35) compared with 2.02 (1.29) µmol/L, P = 0.03] were significantly higher after the high-SCFA diet than after the low-SCFA diet. Blood total B cells [184 (112) compared with 199 (143) cells/µL, P = 0.04], naive B cells [83 (66) compared with 95 (89) cells/µL, P = 0.02], Th1 cells [22 (19) compared with 29 (16) cells/µL, P = 0.03], and mucosal-associated invariant T cells [62 (83) compared with 69 (114) cells/µL, P = 0.02] were significantly lower after the high-SCFA diet than the low-SCFA diet. Increasing colonic and peripheral blood SCFA has discrete effects on circulating immune cells in healthy humans following 3-wk intervention. Further studies (e.g., in patients with inflammatory disease) are necessary to determine whether 1) these changes have immunomodulatory effects, 2) they are therapeutically beneficial, and 3) prolonged intake might be required. This trial is registered at the Australian New Zealand Clinical Trials Registry as ACTRN12618001054202.

PSVIII-18 Nutrient Digestibility of Feedlot Beef Yearling Steers Offered Finishing Diets with Direct fed Microbial Mixtures

Abstract The effects of dietary inclusion of live bacteria on feedlot beef cattle apparent total tract nutrient digestibility were evaluated. Crossbred-Angus yearling steers (n = 192; initial BW = 409 kg ± 8 kg) were blocked by body weight (BW) and randomly assigned into 48 pens (4 steers/pen; 16 pens/treatment) following a randomized complete block design. A steam-flaked corn-based fishing diet was offered ad libitum once daily containing the following treatments: 1) Control, in which no direct fed microbial (DFM) was offered (lactose as carrier only); 2 and 3) Probiotic mixtures at distinct concentrations [Mixture A and B, at 2g/animal-daily (lactose used as carrier)]. Orts DM were quantified (if any) daily and subtracted from total dietary DM offered to calculate DM intake. Fecal samples were collected twice daily (0700 and 1700 h) for 5 consecutive days (d 68 to 72) from at least 3 steers per pen, while feed samples were collected daily. Samples were composited within period, dehydrated (55°C), and ground (1mm) for further analyses. Total fecal output was estimated with a dietary internal marker (288-h indigestible NDF) and used to calculate nutrient digestibility. Data were analyzed using the GLIMMIX procedure of SAS and pen was considered the experimental unit. Intakes of DM, OM, NDF, and ADF during the digestibility assessment were not affected (P ≥ 0.13) by treatments. Steers offered DFM mixture-A tended to increase digestibility of DM (P = 0.07; 79.3 vs. 77.1%), NDF (P = 0.10; 56.9 vs. 51.6%), and hemicellulose (P = 0.08; 59.4 vs. 53.9%) compared with control, while digestibility of ADF was not affected (P = 0.24) by treatment. The DFM mixture-A seemed to positively affect apparent digestibility of nutrients in steers consuming a steam-flaked corn-based finishing diet, in which improvements in the fiber fraction digestion seemed to be a meaningful contributor.

Trace mineral source influences digestion, ruminal fermentation, and ruminal copper, zinc, and manganese distribution in steers fed a diet suitable for lactating dairy cows

High solubility of certain trace minerals (TM) in the rumen can alter nutrient digestibility and fermentation. The objectives of the present studies were to determine the effects of TM source on 1) nutrient digestibility and ruminal fermentation, 2) concentrations of soluble Cu, Zn, and Mn in the rumen following a pulse dose of TM, and 3) Cu, Zn, and Mn binding strength on ruminal digesta using dialysis against a chelating agent in steers fed a diet formulated to meet the requirements of a high producing dairy cow. Twelve Angus steers fitted with ruminal cannulae were adapted to a diet balanced with nutrient concentrations similar to a diet for a high producing lactating dairy cow for 21 d. Steers were then randomly assigned to dietary treatments consisting of 10 mg Cu, 40 mg Mn, and 60 mg Zn/kg DM from either sulfate (STM), hydroxychloride (HTM) or complexed trace minerals (CTM). The experimental design did not include a negative control (no supplemental Cu, Mn, or Zn) because the basal diet did not meet the National Research Council requirement for Cu and Zn. Copper, Mn, and Zn are also generally supplemented to lactating dairy cow diets at concentrations approximating those supplied in the present study. Following a 14-d adaptation period, total fecal output was collected for 5-d. Following the fecal collection period, rumen fluid was collected for Volatile fatty acid (VFA) parameters. On the following day, the same diet was provided for 14 d, without supplemental Cu, Zn, and Mn. This period served as a wash-out period. A pulse dose of 100, 400, and 600 mg of Cu, Zn, Mn, respectively, from either STM, HTM, or CTM, was administered via ruminal cannulae to the steers on day 15. Over a 24-h period ruminal samples were obtained every 2-h. Following centrifugation, the supernatant was analyzed for Cu, Mn, and Zn. Ruminal solid digesta samples from times 0, 12, and 24 h after bolus dosing were exposed to dialysis against Tris-EDTA. Digestibility of NDF and ADF were lesser in STM vs. HTM and vs. CTM supplemented steers. Steers receiving HTM and CTM had greater total VFA concentrations than STM, and molar proportions of individual VFA were not affected by treatment. Ruminal soluble Cu and Zn concentrations were greater post dosing in STM and CTM supplemented steers at 2, 4, and 6 h for Cu and 4, 6, 8, 10 and 12 h for Zn when compared to HTM supplemented steers. The release of Cu and Zn from ruminal solid digesta following dialysis against Tris-EDTA at 12 and 24 h postdosing was greater for steers receiving HTM compared to those receiving STM or CTM. Results indicate trace mineral source impacts: 1) how tightly bound Cu and Zn are to ruminal solid digesta; 2) fiber digestion; 3) and ruminal total VFA concentrations.

Diurnal variations and time to reach steady state of external markers used to estimate fecal excretion in sheep.

We executed two studies to investigate time to reach steady state (EXP1) and diurnal variations (EXP 2) of markers, in order to recommend spot fecal sampling in sheep. Eight lambs were used in EXP 1. Each animal has received titanium dioxide (TDOX) and chromium oxide (COX) together during two periods of 15days. Thirty sheep of the Santa Ines breed were used in EXP 2. Fecal samples were taken with 2-h intervals in the last 5days of each period, simultaneously to total feces collection. A sine-cosine model was used to evaluate EXP 2, and broken-line model for EXP 1. TDOX could complete its recovery after 2.3days, and it could accurately promote fecal estimates after 3days of marker infusion. COX could stabilize after 4.1days, and it could promote fecal estimates after 5days. However, estimated fecal excretion became similar to total feces output after 3days for TDOX and after 6days for COX. For both markers, a total 6days of adaptation period could be summed to a 3-day collection period. Spot sampling was similar to total fecal output at 6:00 to 8:00 on morning and between 5:00 and 7:00 on afternoon for TDOX. Also, COX could be sampled at 6:00 to 8:00 on morning and between 5:00 and 7:00 on afternoon. External markers could be evaluated from 3-day fecal spot collection. Fecal collections could be made before the morning feeding, and around 6 p.m. for both markers.

PSXVI-23 The influence of trace mineral source on digestion, ruminal fermentation characteristics, and mineral solubility in beef cattle fed a high concentrate feedlot diet

Abstract Twelve Angus steers (BW 530.9 ± 22.7kg) fitted with ruminal cannulae were used to determine the impact of trace mineral (TM) source on digestibility and ruminal VFA and soluble concentrations of Cu, Mn, and Zn. Steers were fed a high concentrate diet balanced to meet the requirement of finishing feedlot steers for 21d. Treatments consisted of Cu, Mn, and Zn supplemented at 18, 40, and 90 mg/kg DM, respectively, from either sulfate (STM) or hydroxy trace mineral (HTM) sources (n = 6 steers/treatment; experimental unit = steer). Following a 21-d adaptation period total fecal output was collected for 5 d. Trace mineral sources had no impact on nutrient digestibility. On d 6, rumen fluid was collected at 0, 2, and 4 h post-feeding for VFA analysis. There were no treatment x time interactions for any VFA measured. However, HTM steers had greater (P < 0.05) ruminal molar proportions of propionate and tended (P < 0.07) to have greater molar proportions of valerate compared to STM steers. Steers fed STM had greater (P < 0.05) molar proportions of butyrate compared to HTM steers. Steers were then fed the same high concentrate diet without supplemental Cu, Zn, or Mn for 14 d. On d 15 steers received a pulse dose (via rumen cannula) from either STM or HTM. Ruminal samples were obtained at 2 h intervals starting at -4 and ending at 24 h relative to dosing. There was a treatment x time interaction (P < 0.05) for ruminal soluble Cu concentrations. Ruminal soluble mineral concentrations were greater (P < 0.05) for Cu at 4, 6, 8, and 16 h post-dosing in STM compared to HTM supplemented steers. Results indicate that ruminal solubility of Cu differs between STM and HTM sources and may impact rumen fermentation characteristics.

Antidiarrheal Activity of Four Different Species of Litsea Available in Bangladesh

The objective of the present study includes the evaluation of the antidiarrheal properties of the methanol extracts of Litsea deccanensis Gamble (MELD) bark, Litsealancifolia (Roxb.) Hook. f. MELL),Litseaglutinosa Gamble (MELG) and Litsea monopetala Roxb. (MELM) leavesin Swiss albino mice. The antidiarrheal activity was evaluated by measuring percentage inhibition of diarrheal feces, total fecal output, gastrointestinal motility and by using peristaltic indices. Castor oil was used to induce diarrhea in the experimental animal. The experiments were carried out by using three different doses (100, 200, and 400 mg/kg body weight) of these four plant extracts. The number of wet feces and total weight of the feces were significantly (p < 0.05) and dose-dependently reduced by all the plant extracts and this effect was comparable with standard drug. MELD, MELL, MELG and MELM extracts at dose of 400 mg/kg body weight demonstrated diarrheal inhibition by 43.55%, 45.16%, 32.26% and 41.94%, respectively while it was 98.39% for the standard loperamide. Percentage (%) of fecal output for MELD, MELL, MELG and MELM extracts at the dose of 400 mg/kg were 40.14%, 62.27%, 64.06%, 46.26%, respectively.The gastrointestinal motility induced by castor oil was also reduced noticeably (p < 0.05) by all the plant extracts with the increasing doses. The percentage inhibition of gastrointestinal motility at the dose of 400 mg/kg were 26.26%, 33.22%, 32.36% and 22.52% for the MELD, MELL, MELG and MELM extracts respectively, while it was 27.56% for loperamide. In most cases, all the plant extracts can reduce the peristaltic indices which were comparable to control. The obtained results from this study revealed that the methanol extracts of four different species of Litsea found in Bangladesh may have antidiarrheal potential. It also provides the basis for the traditional use of these plants to treat diarrhea.

Trace mineral source impacts rumen trace mineral metabolism and fiber digestion in steers fed a medium-quality grass hay diet.

Twelve Angus steers (BW 452.8 ± 6.1 kg) fitted with ruminal cannulae were used to determine the impact of trace mineral (TM) source on digestibility, ruminal volatile fatty acid (VFA) composition, ruminal soluble concentrations of Cu, Zn, and Mn, and relative binding strength of trace minerals located in the rumen insoluble digesta fraction. Steers were fed a medium-quality grass hay diet (DM basis: 10.8% CP, 63.1% neutral detergent fiber [NDF], 6.9 mg Cu/kg, 65.5 mg Mn/kg, and 39.4 mg Zn/kg) supplemented with protein for 21 d. Treatments consisted of either sulfate (STM) or hydroxy (HTM) sources (n = 6 steers/treatment) to provide 20, 40, and 60 mg supplemental Cu, Mn, and Zn/kg DM, respectively. Following a 21-d adaptation period, total fecal output was collected for 5 d. Dry matter (P < 0.07) and CP (P < 0.06) digestibility tended to be reduced, and NDF (P < 0.04) and acid detergent fiber (ADF) (P < 0.05) digestibility were reduced in STM- vs. HTM-supplemented steers. On day 6, ruminal fluid was collected at 0, 2, and 4 h post-feeding and analyzed for VFA. There were no treatment x time interactions for VFA. Steers receiving HTM had less (P < 0.02) molar proportions of butyric acid and greater (P < 0.05) total VFA concentrations than STM-supplemented steers. Steers were then fed the same diet without supplemental Cu, Zn, or Mn for 14 d. On day 15 steers received a pulse dose of 20 mg Cu, 40 mg Mn, and 60 mg Zn/kg DM from either STM or HTM (n = 6 steers/treatment). Ruminal samples were obtained at 2-h intervals starting at −4 and ending at 24 h relative to dosing. There was a treatment x time interaction (P < 0.03) for ruminal soluble Cu, Mn, and Zn concentrations. Ruminal soluble mineral concentrations were greater (P < 0.05) for Cu at 4, 6, 8, 10, 12, and 14 h; for Mn at 4 and 6 h; and for Zn at 4, 6, and 8 h post-dosing in STM compared with HTM-supplemented steers. Copper concentrations were greater (P < 0.05) at 12 and 24 h and Zn concentrations in ruminal solid digesta were greater at 24 h in HTM-supplemented steers. Upon dialysis against Tris-EDTA, the percent Zn released from digesta was greater (P < 0.05) at 12 h (P < 0.03) and 24 h (P < 0.05), and the percent Cu released was greater (P < 0.02) at 24 h post-dosing in HTM steers when compared with STM-supplemented steers. Results indicate that Cu and Zn from HTM have low solubility in the rumen and appear to be less tightly bound to ruminal solid digesta than Cu and Zn from STM. The lower ruminal soluble concentrations of Cu and Zn in steers given HTM were associated with greater fiber digestibility.

The effects of the dietary replacement of soybean meal with yellow mealworm larvae (Tenebrio molitor) on the growth, nutrient digestibility and nitrogen output of fattening rabbits

The present study aimed to obtain novel information concerning the effects of the total dietary replacement of soybean meal (SBM) with yellow mealworm (Tenebrio molitor; TM) on the coefficients of total tract apparent digestibility (CTTAD) in the diet and on the nitrogen output of fattening rabbits. Two diets were formulated that included 60 g/kg SBM (SBM diet) or 30 g/kg TM (TM diet) as the main crude protein (CP) source. The TM diet had slightly lower CP content than the SBM diet (141 vs. 150 g/kg). A total of 30 rabbits (Hyplus PS 19 x Hyplus PS 40; males) weaned at the age of 32 day were randomly allocated into 2 groups (15 rabbits per group), individually housed, and fed one of the two diets ad libitum for 47 days. Feed intake was measured daily during the entire fattening period (between 32 and 79 day of age). The total faecal and urine output were individually measured between 57 and 61 day of age. A lower daily weight gain (ADWG) between 32 and 53 day of age (by 6.9 g/day, 12 %; P = 0.034), resulting in lower live weight (LW) at the age of 53 day, and a lower feed intake (ADFI) between 32 and 79 day of age (by 13 g/day, 7 %; P = 0.047) were recorded in rabbits fed the TM diet compared to rabbits fed the SBM diet. The ADWG or feed conversion ratio concerning the entire fattening period, the final LW of rabbits, or the CTTAD of the diets were not affected by treatments. Whatever the diet, on average, losses of nitrogen in faeces represented 26 % of the nitrogen intake. Lower losses of nitrogen in urine (by 0.35 g/day, 32 %; P = 0.007) and total excretion of nitrogen (by 0.53 g/day, 23 %; P = 0.003), as well as a higher nitrogen retention coefficient (by 0.06, 11 %; P = 0.026) were detected in rabbits fed the TM diet compared to rabbits fed the SBM diet. It can be concluded that fattening rabbits effectively utilized the diet containing TM without detrimental effects on the CTTAD of the diets or on their nitrogen output.

Evaluation of Molly model predictions of ruminal fermentation, nutrient digestion, and performance by dairy cows consuming ryegrass-based diets

Several studies have been conducted to improve grazing management and supplementation in pasture-based systems. However, it is necessary to develop tools that integrate the available information linking the representation of biological processes with animal performance for use in decision making. The objective of this study was to evaluate the precision and accuracy of the Molly cow model predictions of ruminal fermentation, nutrient digestion, and animal performance by cows consuming pasture-based diets to identify model strengths and weaknesses, and to derive new digestive parameters when relevant. Model modifications for adipose tissue, protein synthesis in lean body mass and viscera representation were included. Data used for model evaluations were collected from 25 publications containing 115 treatment means sourced from studies conducted with lactating dairy cattle. The inclusion criteria were that diets contained ≥45% perennial ryegrass (Lolium perenne L.), and that dry matter intake, dietary ingredient composition, and nutrient digestion observations were reported. Animal performance and N excretion variables were also included if they were reported. Model performance was assessed before and after model reparameterization of selected digestive parameters, global sensitivity analysis was conducted after reparameterization, and a 5-fold cross evaluation was performed. Although rumen fermentation predictions were not significantly improved, rumen volatile fatty acids absorption rates were recalculated, which improved the concordance correlation coefficient (CCC) for rumen propionate and ammonia concentration predictions but decreased CCC for acetate predictions. Similar degradation rates of crude protein were observed for grass and total mixed ration diets, but rumen-undegradable protein predictions seemed to be affected by the solubility of the protein source as was the intestinal digestibility coefficient. Ruminal fiber degradation was greater after reparameterization, driven primarily by hemicellulose degradation. Predictions of ruminal and fecal outflow of neutral detergent fiber and acid detergent fiber, as well as total fecal output predictions, improved significantly after reparameterization. Blood urea N and urinary N excretion predictions resulted in similar accuracy using both sets of model parameters, whereas fecal N excretion predictions were significantly improved after reparameterization. Body weight and body condition score predictions were greatly improved after model modifications and reparameterization. Before reparameterization, yield predictions for daily milk, milk fat, milk protein, and milk lactose were greatly overestimated (mean bias of 61.0, 58.7, 73.7, and 64.6% of mean squared error, respectively). Although this problem was partially addressed by model modifications and reparameterization (mean bias of 3.2, 1.1, 1.7, and 0.4% of mean squared error, respectively), CCC values were still small. The ability of the model to predict grass digestion and animal performance in dairy cows consuming pasture-based diets was improved, demonstrating the applicability of this model to these productive systems. However, the failure to predict grass digestion based on standard model inputs without reparameterization indicates there are still fundamental challenges in characterizing feeds for this model.

226 Influence of trace mineral source on digestion, ruminal volatile fatty acid and soluble mineral on steers fed a dairy type diet balanced to meet requirements for a high producing lactating dairy cow

Abstract Twelve Angus steers (BW 530.9 ± 22.7kg) fitted with ruminal cannulae were used to determine the impact of trace mineral source on digestibility, ruminal VFA, and soluble concentrations of Cu, Zn, and Mn. Steers were fed a dairy type diet balanced to meet requirements for a high producing lactating dairy cow (DM basis: 16.8% CP, 29.2 Mcal NEm, 30.3 Mcal NEl, 33.6% NDF) for 21 d. Treatments consisted of 10 mg Cu, 40 mg Mn, and 60 mg Zn/kg DM from either sulfate (STM), hydroxy (HTM; IntelliBond) or organic (ORG; metal specific amino acid complexes) sources (n=4 steers/treatment). Following a 21-d adaptation period, total fecal output was collected for 5 d. On d 6, rumen fluid was collected at 0, 2, and 4 h post feeding and analyzed for VFA. Steers were then fed the same diet without supplemental Cu, Zn, or Mn for 14 d. On d 15 steers received a pulse dose (cannulae) of 100 mg Cu, 400 mg Mn, and 60 mg Zn from either STM, HTM, or ORG. Ruminal samples were obtained at 2-h intervals starting at -4 and ending at 24 h post dosing and analyzed for soluble Cu, Mn, and Zn. Digestibility of NDF and ADF were lesser (P &amp;lt; 0.05) in STM vs. HTM and ORG supplemented steers. Steers receiving HTM and ORG had greater (P &amp;lt; 0.05) total VFA concentrations than STM supplemented steers at 2 and 4h post feeding. Ruminal soluble Cu and Zn concentrations were greater (P &amp;lt; 0.001) post dosing in STM and ORG supplemented steers at 2, 4, and 6 h for Cu and 4, 6, 8, 10 and 12 h for Zn when compared to HTM supplemented steers. Results indicate that ruminal solubility of Cu and Zn differs between STM, HTM and ORG sources and trace mineral source impacts fiber digestion and ruminal VFA concentrations.

347 Choosing an external marker for measuring intake and digestibility in ruminants

Abstract Proper nutrition is key to maintaining and improving animal productivity. Measuring intake and site and extent of digestion is essential for appropriate diet formulation. However, it is extremely difficult to accurately account for the dynamic nature of the ruminant digestive tract. External markers have long been used as a tool to measure digesta output, yet proper marker selection can be challenging. The aim of this review is to provide guidance in the selection of external markers in ruminant nutrition studies. External markers must satisfy certain requirements in order to be considered a valid marker. These requirements include, but are not limited to, being inert in the gastrointestinal tract, mixing with the digesta, and having high recovery rate in the feces. In addition, laboratory analysis needs to be easily reproducible within and amongst laboratories. Health hazards of the marker must also be kept in mind for the laboratory worker and the animal. There are a number of elements that have been utilized as external markers. Currently in the literature, chromic oxide (Cr2O3), long-chain alkanes (C32 to C36) and titanium dioxide (TiO2) are the most commonly used external markers. Each have been extensively evaluated and have their own positive and negative attributes. Results comparing fecal recoveries has been extensively reported in various diets fed to large and small ruminants. Of the three most widely utilized external markers, all have demonstrated adequate fecal recoveries, reasonable estimates of total duodenal and fecal digesta flows or output. Therefore, the selection of the appropriate marker comes down to the ease and accuracy at which analysis can be conducted, dosage rate, minimum dosage frequency, and safety to the user and animal.

PSIX-20 Mechanisms of Programmed Nutrition in finishing cattle

Abstract Programmed Nutrition Beef Program (Alltech Inc.) is a supplement that could reduce the use of feed additives such as Monensin and Tylosin in feedlots. The objective of this study was to examine changes in rumen fermentation when feeding Monensin/Tylosin and Programmed Nutrition. Eight steers (BW = 363 ± 22 kg) were used in a replicated 4 x 4 Latin square design experiment in a 2 x 2 factorial treatment structure where animals were fed a high-concentrate diet at 2.0 x NEm. Treatments were Control (C; conventional trace mineral supplement), Control + Monensin + Tylosin (MT), Programmed Nutrition (PN; Programmed Nutrition Beef Finisher), or Programmed Nutrition + Monensin + Tylosin (PNMT), incorporated daily to the diet at 75 g/day. Rumen pH was measured continuously for 48 h, rumen fluid was collected every 2 h for 48 h and analyzed for VFA. Dietary digestibility, nitrogen and energy balance were determined by collection of total urine and fecal output for 7 days, and indirect calorimetry for 48 h. Protein turnover was determined via 15N-glycine end-product method. The experiment was analyzed as a replicated Latin square design with mixed models of SAS (SAS Inst. Inc.). Mean differences were analyzed using LSD, rumen VFA and pH data were analyzed using repeated measures. There were no differences between treatments in DMI, ADG, dry matter digestibility and rumen pH. Addition of MT to the diet lowered fecal N output (P = 0.0092), ruminal valerate concentration (P = 0.0125) and molar proportion (P = 0.0235). When PN was fed in combination with MT it decreased ADF digestibility (P = 0.0342), protein turnover (P = 0.0211), protein synthesis (P = 0.0362) and protein degradation (P = 0.0292). Although no differences in ADG and dry matter digestibility were observed, significant metabolic changes occurred when supplementing PN with or without MT.

52 Effects of an energy or protein supplement on forage dry matter intake for steers grazing summer native range

Abstract The objective of this study was to determine the effects of supplementation level and type on forage intake of steers grazing a high-quality native range. This study was conducted in late May through the end of June. On d 0, steers (n=16, initial BW = 193.7 kg ± 14.3 kg) were randomly assigned to one of 5 dietary treatments, fed once daily in individual stalls for 28 d. Treatments were control (no supplement, n=4), or supplemented with either cottonseed meal or dry rolled corn, each at either 0.45 kg or 1.81 kg as-fed/d (n=3 for each combination). Beginning on d 7, steers were orally administered titanium dioxide boluses (10 g/steer) once daily for 21 d. Fecal samples were collected from the rectum once daily for 14 d, analyzed for Ti concentration via a handheld X-ray fluorescence analyzer, and total fecal output was estimated. Diet digestibility was estimated after a 288-h in situ incubation of forage and fecal samples to determine indigestible NDF. Some steers had orts, therefore actual mean supplement intake was used in analysis. Results were analyzed with regression, with animal as the experimental unit. Mean estimated forage DMI of unsupplemented animals was 1.6% BW. Contrary to expectation, corn supplemented steers exhibited greater forage DMI as a percentage of BW than cottonseed meal supplemented steers (P = 0.01; 1.5 vs. 1.1, respectively).

Molybdenum Exposure in Drinking Water Vs Feed Impacts Apparent Absorption of Copper Differently in Beef Cattle Consuming a High-Forage Diet.

Twelve Angus steers were utilized to investigate the influence of molybdenum (Mo) in drinking water or feed on apparent absorption and retention of copper (Cu) and Mo. Steers were fed a low-quality grass hay diet for 14days. Steers were then housed in individual metabolism stalls and blocked by body weight and dry matter intake (DMI) and randomly assigned within block to one of three treatments. Treatments consisted of (1) control (no supplemental Mo), (2) 5.0mg Mo/kg DM from sodium molybdate dihydrate (Mo-diet), and (3) 1.5mg Mo/L from sodium molybdate dihydrate delivered in the drinking water (Mo-water). Total fecal and urine output were then collected for 5days. Dry matter, Cu and water intake, and DM digestibility were similar across treatments. Molybdenum intake was greater (P < 0.05) in Mo-water and Mo-diet steers when compared to controls but similar between Mo-water and Mo-diet steers. Apparent absorption and retention of Cu were greater (P < 0.05) in controls when compared to Mo-diet supplemented steers. Apparent absorption and retention of Cu in steers in the Mo-water treatment did not differ from controls or those receiving the Mo-diet. Molybdenum-diet and Mo-water supplemented steers had similar apparent absorption and retention of Cu. Apparent absorption and retention of Mo (% of Mo intake) was greater in controls when compared to Mo-supplemented steers. These data indicate that Mo consumed in water may impact Cu absorption and retention to a lesser extent than Mo supplemented in the diet.

Evaluation of the n-alkane technique for estimating the individual intake of dairy cows consuming diets containing herbage and a partial mixed ration

Estimation of dry matter intake (DMI) using the n-alkane technique was evaluated in lactating dairy cows fed fresh herbage and a partial mixed ration (PMR). Four dietary treatments were investigated in a 2 × 2 factorial experiment using 16 Holstein-Friesian dairy cows. Dietary treatments were combinations of low and high amounts of fresh herbage (8 or 14 kg DM/cow per day) and PMR supplement (6 or 12 kg DM/cow per day). The pre-experimental period was 14 days followed by a 10-day experimental period. Cows were housed in individual metabolism stalls to allow for accurate measurement of DMI and total fecal output. Fecal n-alkane recovery rates were calculated to determine the most accurate corrections for incomplete fecal n-alkane recovery. The n-alkane technique accurately estimated DMI when corrected for incomplete fecal recovery using both published recovery rates and recovery rates calculated in this experiment. The most accurate application of recovery rates was with those calculated for each combination of dietary treatments, compared with using an average recovery rate. This research has important implications for the future use of the n-alkane technique, especially in PMR feeding systems. The discrepancy between estimated (when treatment recovery rates were applied) and measured herbage DMI increased with the amount of herbage offered but was not affected by amount of PMR. It was also found that the recovery rates of all natural n-alkanes increased as the amount of herbage increased. This research demonstrates that the n-alkane technique can be used to accurately estimate individual cow intake when fresh herbage and PMR are offered separately, evidenced by strong Lin’s concordance estimates.

Reliability of acid-insoluble ash as internal marker for the measurement of digestibility in rabbits

&lt;p&gt;The present study aimed to evaluate acid-insoluble ash (AIA) as an internal marker for the measurement the coefficient of total tract apparent digestibility (CTTAD) in rabbits through two experiments (E1 and E2). In E1, 48 rabbits were used to calculate the CTTAD of the same basal diet according to the European reference method (ERM), the AIA and the titanium dioxide (TiO&lt;sub&gt;2&lt;/sub&gt; with 1 g of TiO&lt;sub&gt;2&lt;/sub&gt;/kg diet) techniques (n=16 rabbits/method). The effect of feed sample quantity on dietary AIA content was investigated and total collection of faeces was carried out to calculate marker recovery. In E2, 48 rabbits were allotted to three groups fed diets with no sugar beet pulp (SBP0) or with 100 (SBP100) and 200 (SBP200) g sugar beet pulp/kg (n=16 rabbits/group). Each group was divided into two subgroups, ERM and AIA (n=8 rabbits/subgroup), in which CTTAD was measured using the European reference and AIA method, respectively. In AIA subgroups, only 10% of the total daily faecal output was sampled from 9:00 to 9:30 am. Feed analysis in E1 showed that increasing sample quantity from 5 to 9 g did not affect the dietary AIA content; however, the analytical error was 7 and 5 times lower (&lt;em&gt;P&lt;/em&gt;&amp;lt;0.05) for 9 g, when compared to 5 and 7 g samples. Feed analysis also showed 1.030±0.003 g TiO&lt;sub&gt;2&lt;/sub&gt;/kg diet. Faecal marker recovery was 99.80±0.03 and 96.89±0.16% for AIA and TiO&lt;sub&gt;2&lt;/sub&gt;, respectively. The CTTAD of dry matter (DM), did not differ between methods in E1, but a 5-fold higher variability (&lt;em&gt;P&lt;/em&gt;&amp;lt;0.05) was observed for the TiO&lt;sub&gt;2&lt;/sub&gt; technique in comparison with the ERM and AIA methods. Also, no differences in the CTTAD of DM between the ERM and AIA methods were found in E2. In conclusion, AIA is a reliable internal marker in rabbits and offers the possibility of measuring the CTTAD of diets with precision, when complete faecal collection or feed intake measurement is not possible.&lt;/p&gt;

Cricket (Gryllodes sigillatus) meal fed to healthy adult dogs does not affect general health and minimally impacts apparent total tract digestibility.

Insects can serve as a novel high-quality protein source for pet foods. However, there is an absence of research investigating the use of insects in pet food. The study objective was to evaluate the apparent total tract digestibility and possible health effects of diets containing graded levels of cricket (Gryllodes sigillatus) meal fed to healthy adult dogs. Thirty-two adult Beagles were randomly assigned to one of four dietary treatments: 0%, 8%, 16%, or 24% cricket meal. Dogs were fed their respective diet for a total of 29 d with a 6-d collection phase. Fecal samples were collected daily during the collection phase to measure total fecal output as well as apparent total tract digestibility for dry matter (DM), organic matter, crude protein, fat, total dietary fiber, and gross energy. Blood samples were taken prior to the study and on day 29 for hematology and chemistry profiles. Data were analyzed in a mixed model including the fixed effects of diet and sex. Total fecal output increased on both an as-is (P = 0.030) and DM basis (P = 0.024). The apparent total tract digestibility of each nutrient decreased (P < 0.001) with the increasing level of cricket meal inclusion. All blood values remained within desired reference intervals indicating healthy dogs. Slight fluctuations in blood urea nitrogen (P = 0.037) and hemoglobin (P = 0.044) levels were observed but were not considered of biological significance. Even with the decrease in digestibility with the inclusion of cricket meal, diets remained highly digestible at greater than 80% total apparent digestibility. In conclusion, crickets were demonstrated to be an acceptable ingredient for dog diets.

PSXII-18 The influence of molybdenum in drinking water or feed on apparent absorption and retention of molybdenum and copper in beef steers

Abstract Twelve Angus steers (BW 694.1 ± 47.4 kg) fitted ruminal cannulae were used to examine the effect of molybdenum (Mo) supplemented in drinking water or feed on apparent absorption and retention of Mo and copper (Cu). Steers were fed a low-quality grass hay diet (DM basis: 6.5% CP; 0.13% S, 3.4 mg Cu/kg, 2.4 mg Mo/kg) for 14 d. Steers were then housed in individual metabolism stalls for 3 d to determine DMI. Steers were then blocked by BW and DMI and randomly assigned within block to one of three treatments (n = 4 steers per treatment). Treatments consisted of: 1) Control (no supplemental Mo); 2) 5.0 mg Mo/kg DM from sodium molybdate dihydrate (Mo-diet), and 3) 1.5 mg Mo/l from sodium molybdate dihydrate delivered in the drinking water (Mo-water). After the 3d DMI determination period, total fecal and urine output was collected for 5 d. Dry matter intake and DM digestibility were similar across treatments. Data were analyzed using a mixed effects model (PROC MIXED, SAS) for a completely randomized block design. Apparent absorption of Cu was greater (P &amp;lt; 0.05) in Control and Mo-water steers when compared to Mo-diet steers. Apparent retention of Cu was greater (P &amp;lt; 0.05) in Control steers when compared to Mo-diet steers. Steers receiving Mo-water had a similar apparent retention of Cu when compared to Control and Mo-diet steers. By design, treatment was a significant (P &amp;lt; 0.01) source of variation for Mo intake. Control steers had lesser (P &amp;lt; 0.05) Mo intake when compared to Mo-diet and Mo-water supplemented steers. Apparent absorption and retention of Mo were greater (P &amp;lt; 0.05) in Mo-diet steers compared to Control and Mo-water steers. These data indicate that Mo metabolism and apparent absorption of Cu are different when Mo is supplemented in water relative to feed.