Fecal Grab Samples Research Articles

Effect of Yeast Culture on Efficiency of Nutrient Utilization for Milk Production and Impact on Fiber Digestibility and Fecal Particle Size

Approximately 260 Holstein cows on a commercial dairy were utilized in a switchback study. Treatments consisted of control or 56 g/d of yeast culture. The objectives of this experiment were to quantify the benefit of yeast culture on 1) efficiency of milk production, and 2) nutrient flows within the dairy system that utilizes a solids separator. Milk yield was recorded every 12 d. Pen feed intakes and refusals were recorded daily. Manure fiber particle size was determined from fecal grab samples via wet sieving. In addition, a mixture of feces plus water was sieved through a screen to replicate a manure solids separator. Cows receiving yeast culture showed numerically greater DMI (0.13 kg/d), an increase (P < 0.001) in BW gain, greater milk fat content (P < 0.02), greater (P < 0.08) milk fat yield, less milk protein content (P < 0.03), and similar milk protein yield (P > 0.05). Milk yields were similar between treatments; however, there was a trend for an increase (P < 0.19) in 3.5% fat corrected milk for cows fed yeast culture. Control cows had numerically lower NDF digestibility. Distribution of fecal particles suggests more manure solids may pass the manure solids separator to the manure lagoon and therefore reduce the amount of manure solids collected with the separator. Yeast culture was shown to impact nutrient use by the animal and affect manure particle partition.

Development of an Experimental Model To Assess the Ability of Escherichia coli O157:H7–Inoculated Fecal Pats To Mimic a Super Shedder within a Feedlot Environment

This study was conducted to develop an experimental model that could assess the ability of Escherichia coli O157:H7–inoculated fecal pats to mimic a super shedder (>104 CFU/g of feces) within a feedlot environment. The day before the study began, 48 steers that had been negative for E. coli O157:H7 in feces for three consecutive weeks were sorted into three treatment groups, with two replicate pens per treatment and 8 steers per pen. Steers within the pens (20.50 by 10.75 m) were exposed to control feces or feces inoculated with two levels of a mixture of five strains of nalidixic acid–resistant E. coli O157:H7 (low level, 102 CFU/g; high level, 105 CFU/g). Five 300-g fecal pats were introduced into the pens twice daily (10:00 a.m. and 2:30 p.m.) on days 0 through 6 and days 14 through 20. Pats were placed in the pen at random locations to mimic defecation of a steer within the pen. Fecal grab samples, hide swab samples (500-cm2 area of the rump), natural fecal pat samples (freshly voided), and rope samples (1.22-m-long manila rope) where obtained at multiple times during the 49-day trial to evaluate the spread of nalidixic acid–resistant E. coli O157:H7 throughout the feedlot environment and among penmates. Immunomagnetic separation and selective media were used to detect E. coli O157:H7. Nalidixic acid–resistant E. coli O157:H7 was detected in 13 high-level treatment fecal grab samples, 7 high-level treatment hide swab samples, 1 low-level hide swab sample, and 2 high-level rope samples. For both fecal grab and hide swab samples, the overall prevalence of

Use of Fecal Samples as a Tool to Monitor Phosphorus Excretion in Lactating Dairy Cows

ABSTRACT Lactating Holstein cows were used to determine if disrupting their TMR intake by feeding a top-dress of alfalfa hay affected the diurnal concentration of P in feces and the usefulness of fecal P to monitor P excretion. All cows were fed the control TMR at 1400 h daily, but treatment cows were fed 2.27 kg (DM) of alfalfa hay at 0700 h. Cows had ad libitum access to feed except between 0800 to 1000 h and 1100 to 1400 h. Both diets contained 0.42% P. On d 21, fecal grab samples were collected every 4 h for 48 h to represent every 2 h in a diurnal period. Neither DMI (26 kg/d) nor milk yield (38 kg/d) was affected (P > 0.1) by treatment. The concentration of P in the feces (0.70 and 0.71% DM for control and treatment cows, respectively) was not affected (P > 0.1) by supplemental hay nor did it change diurnally. Therefore, for dairy cows fed a TMR containing 0.42% P there was no diurnal change in the concentration of P in feces, and a forage top-dress did not affect the concentration of P in feces. Thus, fecal grab sampling appears to be a reasonable method to monitor P excretion. In conclusion, because of the variation in the concentration of P in fecal samples, the number of cows sampled within a group is more important than the time during the day that the samples are taken.

Utilization of distillers dried grains with solubles and phytase in sow lactation diets to meet the phosphorus requirement of the sow and reduce fecal phosphorus concentration1

Two experiments were completed to determine the potential for using distillers dried grains with solubles (DDGS) in diets with or without phytase to provide available P, energy, and protein to highly productive lactating sows without increasing their fecal P. In Exp. 1, the dietary treatments were as follows: (1) corn and soybean meal with 5% beet pulp (BP) or (2) corn and soybean meal with 15% DDGS (DDGS). Besides containing similar amounts of fiber, diets were isonitrogenous (21% CP, 1.2% Lys) and isophosphorus (0.8% P). Sixty-one sows were allotted to dietary treatments at approximately 110 d of gestation (when they were placed in farrowing crates) based on genetics, parity, and date of farrowing. Sows were gradually transitioned to their lactation diet. On d 2 of lactation, litters were cross-fostered to achieve 11 pigs/litter. Sows and litters were weighed on d 2 and 18. Fecal grab samples were collected on d 7, 14, and 18 of lactation. Dietary treatment did not affect the number of pigs weaned (10.9 vs. 10.8) or litter weaning weight. On d 14, DDGS sows had less fecal P concentration than BP sows (28.3 vs. 32.8 mg/g; P = 0.04). Fecal Ca of sows fed DDGS decreased for d 7, 14, and 18 (55.6, 51.4, and 47.1 mg/g of DM, respectively; P = 0.05) but not for BP sows. In Exp. 2, the dietary treatments were as follows: (1) corn and soybean meal (CON), (2) CON + 500 phytase units of Natuphos/kg diet, as fed (CON + PHY), (3) corn and soybean meal with 15% DDGS and no phytase (DDGS), or (4) DDGS + 500 FTU of Natuphos/kg of diet, as fed (DDGS + PHY). Sows (n = 87) were managed as described for Exp 1. Litter BW gain (46.0, 46.3, 42.1, and 42.2 kg; P = 0.25) and sow BW loss (8.1, 7.2, 7.4, and 6.3 kg for CON, CON + PHY, DDGS, and DDGS + PHY, respectively; P = 0.97) were not affected by dietary treatment. Fecal P concentration did not differ among dietary treatments but was reduced at d 14 and 18 compared with d 7 (P = 0.001). However, fecal phytate P concentration was decreased by the addition of DDGS when DDGS and DDGS + PHY were compared with the CON sows except on d 7 (P < 0.05). Sows fed CON diet had greater fecal phytate P than sows fed DDGS, and sows fed DDGS + PHY had less fecal phytate P than sows fed DDGS with no phytase (P = 0.001). Although these experiments were only carried out for 1 lactation, these results indicate that highly productive sows can sustain lactation performance with reduced fecal phytate P when fed DDGS and phytase in lactation diets.

Manure Nutrient Excretion by Lactating Cows Fed Exogenous Phytase and Cellulase

The effect of an exogenous phytase and cellulase-containing enzyme formulation on nutrient digestibility and excretion was evaluated in 24 Holstein cows. Cows were fed corn silage- and alfalfa silage-based diets with or without a cellulase-phytase blend for 31 d in a continuous random design. Treatment groups were balanced for parity, days in milk, and mature-equivalent projected milk yield. Diets contained 37% forage, 18.3% crude protein, 35.4% neutral detergent fiber, 18% acid detergent fiber, and 0.42% P (no supplemental P). Cows were fed once daily in Calan doors and milked 2 times daily. Body weight and milk yield were recorded at each milking. Milk samples were collected on d 28 to 31 at 8 consecutive milkings. On d 28 to 31, fecal grab samples were collected every 8h, with sampling times advanced by 2h each day. Feces samples were pooled by cow. Feed and feces samples were analyzed for acid detergent lignin (used as an internal marker) and for N, P, neutral detergent fiber, and acid detergent fiber. Days in milk were similar between treatments, and body weight and milk yield were unaffected by treatment. Cows fed the enzyme formulation had reduced fecal dry matter, neutral detergent fiber, and acid detergent fiber excretion and reduced fecal excretion of N and P. Apparent digestibility of dry matter, acid detergent fiber, neutral detergent fiber, and N tended to increase with the enzyme formulation. Addition of an exogenous phytase and cellulase enzyme formulation to diets for lactating cows reduced fecal nutrient excretion.

Distribution of Escherichia coli O157 and Salmonella on Hide Surfaces, the Oral Cavity, and in Feces of Feedlot Cattle

To determine the distribution of pathogens on cattle hides at the feedlot, samples were collected from six hide surface locations (back, flank, hock, neck, perineum, and ventrum), the oral cavity, the rectal-anal junction, and the feces of feedlot cattle and subjected to Escherichia coli O157 detection via culture methods and to Salmonella detection via PCR. E. coli O157 was isolated from one or more of the sampling locations from 31 (42.5%) of the 73 animals sampled. Location-specific prevalence of E. coli O157 was 5% for back samples, 5% for flank samples, 12% for hock samples, 7% for neck samples, 12% for perineum samples, 8% for ventrum samples, 1% for oral cavity samples, 4% for rectal-anal junction swabs, and 23% for fecal grab samples. Salmonella was isolated from one or more of these sample locations from 100% (50 of 50 samples) of all animals sampled. Location-specific prevalence of Salmonella was 76% for back samples, 74% for flank samples, 94% for hock samples, 76% for neck samples, 88% for perineum samples, 86% for ventrum samples, 94% for oral cavity samples, 64% for rectal-anal junction swabs, and 50% for fecal grab samples. The sampling locations that maximized the likelihood of finding E. coli O157 and Salmonella (84 and 96%, respectively) if the animal was positive at one sampling location or more were the hock, perineum, and fecal grab. These data suggest that the use of multiple sample locations is useful when isolating these pathogens from feedlot cattle. Focusing on one sampling location may underestimate the prevalence.

Effect of Direct-Fed Microbials on Performance, Diet Digestibility, and Rumen Characteristics of Holstein Dairy Cows

The objective of this study was to determine the effect of feeding direct-fed microbial (DFM) products containing Lactobacillus acidophilus and Propionibacteria freudenreichii on the performance, nutrient digestibility, and rumen fermentation of Holstein dairy cows in midlactation. Experiments were conducted from February to May 2003. Cows were fed 1 of 3 dietary treatments: 1) 1×109 colony-forming units (cfu)/d of live L. acidophilus strain LA747 and 2×109 cfu/d of live P. freudenreichii strain PF24 (DFM1); 2) 1×109 cfu/d of live L. acidophilus strain LA747, 2×109 cfu/d of live P. freudenreichii strain PF24, and 5×108 cfu/d of L. acidophilus strain LA45 (DFM2); or 3) lactose (control). Treatments were administered by mixing 45g of finely ground corn with 5g of DFM products or lactose and top dressing on the total mixed rations once daily. All cows received the same total mixed ration: 12.7% alfalfa hay, 46.2% corn silage, and 41.1% concentrate on a dry matter (DM) basis. In study 1 (lactation study), 39 multiparous and 18 primiparous Holstein cows were blocked by parity and randomly assigned to treatments for 84 d. Starting on d 35, fecal grab samples were collected from each cow at 5- to 8-h intervals over 48h for digestibility measurements. A rumen fermentation study (study 2) was conducted concurrently with the lactation study. Three rumenfistulated, multiparous Holstein cows were randomly assigned to dietary treatments DFM1, DFM2, and control in a 3×3 Latin square design with 28-d periods. In study 1, there was no difference in average DM intake (23.9, 23.6, and 24.2 kg/d) or 4% fat-corrected milk (36.8, 35.3, and 36.2 kg/d) for treatments DFM1, DFM2, and control. Percentage or yield of milk components also did not differ among treatments. Feed efficiency averaged 1.52kg of 4% fat-corrected milk/kg of DM intake and did not differ among treatments. There were no differences in apparent DM, crude protein, neutral detergent fiber, or starch digestibility among treatments. In study 2, there was no difference in rumen pH and concentrations of ammonia or total volatile fatty acids measured at 0, 1, 3, and 6h after feeding. Under the conditions of these studies, supplementing midlactation cows with DFM products containing L. acidophilus and P. freudenreichii did not affect cow performance, diet digestibility, or rumen fermentation.

Effects of water and diet acidification with and without antibiotics on weanling pig growth and microbial shedding1,2

Two 5-wk experiments were conducted to determine the effects of water and diet acidification with and without antibiotics on weanling pig growth performance and microbial shedding. In Exp. 1, 204 pigs (19.2 d of age) were used in a 3 x 2 factorial, with 3 dietary treatments fed with or without water acidification (2.58 mL/L of a propionic acid blend; KEM SAN, Kemin Americas, Des Moines, IA). Dietary treatments were: 1) control, 2) control + 55 ppm of carbadox (CB), and 3) dietary acid [DA; control + 0.4% organic acid-based blend (fumaric, lactate, citric, propionic, and benzoic acids; Kemin Americas)] on d 0 to 7 followed by 0.2% inorganic acid-based blend (phosphoric, fumaric, lactic, and citric acids; Kemin Americas) on d 7 to 34. In Exp. 2, 210 pigs (average 18.3 d of age) were fed 1 of 3 dietary treatments: 1) control, 2) control + 55 ppm of CB, and 3) control + 38.6 ppm of tiamulin + 441 ppm of chlortetracycline on d 0 to 7 followed by 110 ppm of chlortetracycline on d 7 to 35 (TC) with or without dietary acidification (same as Exp. 1) in a 3 x 2 factorial arrangement of treatments. For both experiments, the pigs were allotted based on genetics, sex, and initial BW [5.5 kg (Exp. 1) or 5.6 kg (Exp. 2)]. Pigs were housed at 6 or 7 (Exp. 1) and 7 (Exp. 2) pigs/pen. Treatments were fed in 3 phases: d 0 to 7, 7 to 21, and 21 to 35 (34 d, Exp. 1). Fecal grab samples were collected from 3 pigs/pen on d 6, 20, and 33 for measurement of pH and Escherichia coli. During phase 3 and overall in Exp. 1, pigs fed CB had greater (P < 0.001) ADG (overall ADG, 389 vs. 348, and 348 g/d, respectively), ADFI (P < 0.007, 608 vs. 559, and 554 g/d, respectively), and d 34 BW (P < 0.001, 18.8 vs. 17.3, and 17.3 kg, respectively) than pigs fed NC and DA. Phase 3 ADG was improved (P < 0.01) by water acidification across all diets. In Exp. 2, pigs fed CB and TC had greater ADG (P < 0.004; 315 and 303 vs. 270 g/d, respectively), ADFI (P < 0.01), and d 35 BW (P < 0.002; 16.7 and 16.2 vs. 15.1 kg, respectively) than pigs fed NC. There was a tendency (P < 0.08) for an improvement in ADG when DA was added to the NC or TC, but decreased ADG when DA was added to CB.

Using plant wax markers to estimate diet composition and intakes of mixed forages in sheep by feeding a known amount of alkane-labelled supplement

The feeding of known amounts of supplements to grazing animals can be accomplished relatively easily. If the supplement and the other diet components have distinctive profiles of cuticular wax n-alkanes, then the supplement intake and the alkane profiles of the supplement, other dietary components and faeces can be used to estimate the proportions and hence intakes of several forages by the grazing animal. However, this method requires knowledge of recoveries of n-alkanes in faeces. Twenty four wethers were fed one of four diets comprising equal combinations of 1, 2, 3 or 4 forages. Forages used were subterranean clover, phalaris, annual ryegrass and wheat straw. Forages were chopped using a chaff cutter and fed with solvent-extracted cottonseed meal (CSM) labelled with beeswax and synthetic C28 alkane to provide a characteristic alkane profile. Faecal grab samples were taken from sheep from 14 to 23 days after administration of an intra-ruminal controlled-release device (CRD) containing 1 g of each of C32 and C36 alkane. Total faeces were collected from half the sheep on each treatment in order to measure alkane recoveries in individual sheep. Faecal concentrations of the n-alkanes C25 to C31 and C33 were corrected for recovery using the individual sheep value, the treatment mean or the grand mean for all four treatments. Dietary compositions were then estimated from corrected faecal concentrations of n-alkanes using a least-squares procedure and, together with the known supplement intakes, were used to estimate the intakes of all other diet components. Estimates from this ‘labelled supplement’ method were compared with the amounts fed or those estimated using the alkanes derived from the CRD. The labelled supplement method accurately and precisely estimated dietary component proportions and intake for all treatments when measured recoveries for individual sheep were used. Precision declined when recovery was based on estimated recoveries for treatment means or the grand mean. Estimates of intake based on dietary C33 and the measured release rates of C32 or C36 alkanes from the CRD did not differ from measured intakes. Estimates based on the C32 : C31 alkane pair over-estimated intake. Estimates of whole-diet digestibility based on the various ways of estimating intake were all very close to the digestibilities calculated from directly-measured intakes and faecal outputs. It is concluded that the feeding of a known amount of supplement can be successfully used to estimate dietary proportions and hence intakes of diet components, in mixed diets with up to five ingredients, but this approach requires estimates of faecal alkane recovery.

Shedding of Escherichia coli O157:H7 by Cattle Fed Diets Containing Monensin or Tylosin

Monensin and tylosin have activity against gram-positive bacteria, and it has been theorized that their effects on the intestinal environment may promote proliferation of gram-negative bacteria such as Escherichia coli. Effects of these antibiotics on the shedding of E. coli O157:H7 were studied in a feedlot environment, using 32 finishing steers. A diet containing 85% barley grain, 10% barley silage, and 5% supplement was amended with 33 ppm monensin, 11 ppm tylosin, both of these additives, or no additives (control). All steers were orally inoculated with 1010 CFU of a mixture of four strains of nalidixic acid–resistant E. coli O157:H7. Fecal (grab), oral (mouth swab) and water, water–water bowl interface, feed, and pen floor fecal pat samples were collected weekly for 12 weeks. Prevalence of E. coli O157:H7–positive fecal grab samples did not differ (P = 0.26) among treatments, nor did the rate (P = 0.81) or duration (P = 0.85) of shedding of the organism. Fecal grab samples were positive for E. coli O157:H7 more frequently (P < 0.001) than were oral swabs. More (P = 0.02) E. coli O157:H7–positive oral swabs were recovered from the tylosin group than from controls. E. coli O157:H7 was not detected in any of 47 water samples, but was present in 1 of 47 water bowl swabs, 7 of 48 feed samples, and 36 of 48 fecal pats. Pulsed-field gel electrophoresis suggested that differences existed among inoculated strains in their ability to persist in animals and in the environment. However, this study revealed no evidence that dietary inclusion of monensin or tylosin, alone or in combination, increased fecal shedding of E. coli O157:H7 or its persistence in the environment.

Effect of graded doses and a high dose of microbial phytase on the digestibility of various minerals in weaner pigs1

An experiment with 224 weaner pigs (initial BW of 7.8 kg) was conducted to determine the effect of dose of dietary phytase supplementation on apparent fecal digestibility of minerals (P, Ca, Mg, Na, K, and Cu) and on performance. Four blocks, each with 8 pens of 7 pigs, were formed. Eight dietary treatments were applied to each block in the 43-d experiment: supplementation of 0 (basal diet), 100, 250, 500, 750, 1,500, or 15,000 phytase units (FTU) or of 1.5 g of digestible P (dP; monocalcium phosphate; positive control) per kilogram of feed. The basal diet, with corn, barley, soybean meal, and sunflower seed meal as the main components, contained 1.2 g of dP per kilogram of feed. Fresh fecal grab samples were collected in wk 4 and 5 of the experiment. Average daily feed intake, ADG, G:F, and digestibility of all of the minerals increased (P < 0.001) with increasing phytase dose. Digestibility of P increased from 34% in the basal diet to a maximum of 84% in the diet supplemented with 15,000 FTU, generating 1.76 g of dP per kilogram of feed. At this level, 85% of the phytate phosphorus was digested, compared with 15% in the basal diet. Compared with the basal diet, digestibility of the monovalent minerals increased maximally at 15,000 FTU, from 81 to 92% (Na) and from 76 to 86% (K). In conclusion, phytase supplementation up to a level of 15,000 FTU/kg of a dP-deficient diet improved performance of weaner pigs and digestibility of minerals, including monovalent minerals. Up to 85% of the phytate-P was digested. Thus, dietary phytase supplementation beyond present day standards (500 FTU/kg) could further improve mineral use and consequently reduce mineral output to the environment.

Excretion patterns of titanium dioxide and chromic oxide in duodenal digesta and feces of ewes

Our objective was to examine differences in marker excretion patterns between Cr 2O 3 and TiO 2 in mature ewes fed diets varying in level of forage. Three experiments were conducted using an all forage diet, a 50% forage diet, and a 25% forage diet. In all three experiments, ewes were dosed intraruminally twice daily at feeding with gelatin boluses containing 2.5 g Cr 2O 3 and 2.5 g TiO 2. Following 7 days of adaptation to markers, fecal grab samples were collected at 6-h intervals for 6 days, representing every 1-h interval in a theoretical 24-h clock. On days 14–16 of each experiment, spot samples of duodenal digesta were collected at times representing 0, 2, 4, 6, 8, and 10 h after the morning feeding. Duodenal TiO 2 and Cr 2O 3 concentrations exhibited a diurnal pattern after feeding in all three experiments, but there were no marker × time interactions. Although fecal concentrations of TiO 2 were higher than Cr 2O 3 in all three experiments, there were no significant marker × time interactions observed. The lack of significant marker × time interactions resulted in little effect of sample collection frequency on mean concentrations of either marker, and as such, the frequency with which either duodenal or fecal samples are collected may be reduced in animals dosed twice daily without markedly affecting mean marker concentrations. Although estimates of digesta flow may differ between markers, the patterns of marker excretion observed suggest that TiO 2 behaves similarly to Cr 2O 3 within the gastrointestinal tract, and thus is an acceptable alternative to Cr 2O 3 for use in site and extent of digestion studies with ruminants.

Comparison of Dectomax® and Valbazen® on feedlot steer performance and carcass traits (2005)

Two hundred thirty-nine steers were fed at the K-State Agricultural Research Southeast Agricultural Research Center Center- Hays to compare the effects of different deworming agents on feedlot performance and carcass traits. This experiment consisted of two replications with steers being fed a finishing diet based on ground sorghum-grain for approximately 100 days. Before the start of each replication, steers were commingled for approximately 30 days and then stratified into high- and low-marbling groups via ultrasound measurements. Within each marbling group, steers were randomly allotted to a treatment. Treatments consisted of an oral application of Valbazen® or a subcutaneous injection of Dectomax® dewormer. Dosages of deworming products followed label instructions. At time of treatment and 12 days later, fecal grab samples were analyzed for indications of internal parasite infestation. Both deworming agents reduced fecal egg counts. Feedlot performance, as measured by daily gain and feed efficiency, was unaffected by treatment. Dectomax®-treated cattle had greater marbling scores and had a greater percentage of carcasses grading USDA Choice or greater than did cattle given Valbazen®. Steers receiving Dectomax® had thicker backfat and greater Yield Grade measurements than did the Valbazen®-treated steers. Other carcass traits were similar between treatment groups. Our data indicate that both Dectomax® and Valbazen® deworming agents can effectively reduce internal parasites, but feedlot steers given Dectomax® had more intramuscular and external fat deposition.

Effect of cyadox on growth and nutrient digestibility in weanling pigs

The effect of cyadox on growth and apparent digestibility of nutrients in weanling pigs was investigated. Cyadox (2-formylquinoxaline-N1,N4-dioxide cyanocetylhydrazone) is a derivative of quinoxaline-1, 4-dioxide, a growth promoting antimicrobial agent that is used in pig production. Seventy-five crossbred weanling barrows were randomly assigned to three treatments with five replicates per treatment. The three dietary treatments consisted of an unmedicated diet (control), a diet containing 100 mg/kg of cyadox and a diet containing 100 mg /kg of olaquindox. The body weight and feed consumption of the pigs were measured weekly for the 4-week experimental period. During week 4 a digestibility study was conducted, and faecal grab samples were collected for six days from each pen. The pigs fed cyadox had significantly higher average daily gains and improved feed conversion efficiencies compared to the control. Cyadox did not affect average daily feed intake. The apparent digestibility of dry matter, crude protein, ether extract, nitrogen free extract, calcium, phosphorus and gross energy was significantly increased in the cyadox-fed pigs above the control. Inclusion of cyadox significantly improved the apparent digestibility of iron, copper, zinc and manganese, and that of several essential and nonessential amino acids. It is suggested that the growth promoting effect of cyadox may be attributed to the improvement in the apparent digestibility of dietary nutrients.. Keywords : Cyadox; pig; average daily gain; feed conversion efficiency;digestibility; amino acids; mineral elements South African Journal of Animal Sciences Vol. 35 (2) 2005: pp.117-125

Copper proteinate in weanling pig diets for enhancing growth performance and reducing fecal copper excretion compared with copper sulfate1

Two 28-d experiments were conducted to evaluate the efficacy of low dietary concentrations of Cu as Cu-proteinate compared with 250 ppm Cu as CuSO4 with growth performance, plasma Cu concentrations, and Cu balance of weanling swine as the criteria. In the production study (Exp. 1), 240 crossbred pigs that averaged 19.8 d of age and 6.31 kg BW initially were group-fed (two or three pigs per pen) the basal diets (Phase 1: d 0 to 14 and Phase 2: d 14 to 28) supplemented with 0 (control), 25, 50, 100, or 200 ppm Cu as Cu-proteinate, or 250 ppm Cu as CuSO4 (as-fed basis). The basal diets contained 16.5 ppm Cu supplied as CuSO4 before supplementation with Cu-proteinate or 250 ppm Cu as CuSO4. There were quadratic responses (P ≤ 0.05) in ADFI and ADG for wk 1, Phases 1 and 2, and overall because ADFI was higher for pigs fed 25 or 50 ppm Cu as Cu-proteinate, and ADG increased with increasing Cu-proteinate up to 50 ppm Cu. The Cu-proteinate treatment groups combined had a higher (P ≤ 0.05) Phase 2 and overall ADFI and ADG than the CuSO4 group. In the mineral balance study (Exp. 2), 20 crossbred barrows that averaged 35 d of age and 11.2 kg/BW initially were placed in individual metabolism pens with total urine and fecal grab sample collections on d 22 to 26. Treatments were the basal Phase 2 diet supplemented with 0, 50, or 100 ppm Cu as Cu-proteinate, or 250 ppm Cu as CuSO4 (as-fed basis). Treatments did not differ in growth performance criteria. There were linear increases (P < 0.001) in Cu absorption, retention, and excretion (milligrams per day) with increasing Cu-proteinate. Pigs fed 100 ppm Cu as Cu-proteinate absorbed and retained more Cu and excreted less Cu (mg/d, P ≤ 0.003) than pigs fed 250 ppm Cu as CuSO4. Plasma Cu concentrations increased linearly (P = 0.06) with increasing Cu-proteinate. In conclusion, weanling pig growth performance was increased by 50 or 100 ppm Cu as Cu-proteinate in our production Exp. 1, but not in our balance Exp. 2, compared with 250 ppm Cu as CuSO4. However, 50 or 100 ppm Cu as Cu-proteinate increased Cu absorption and retention, and decreased Cu excretion 77 and 61%, respectively, compared with 250 ppm Cu as CuSO4.

Copper proteinate in weanling pig diets for enhancing growth performance and reducing fecal copper excretion compared with copper sulfate1

Two 28-d experiments were conducted to evaluate the efficacy of low dietary concentrations of Cu as Cu-proteinate compared with 250 ppm Cu as CuSO4 with growth performance, plasma Cu concentrations, and Cu balance of weanling swine as the criteria. In the production study (Exp. 1), 240 crossbred pigs that averaged 19.8 d of age and 6.31 kg BW initially were group-fed (two or three pigs per pen) the basal diets (Phase 1: d 0 to 14 and Phase 2: d 14 to 28) supplemented with 0 (control), 25, 50, 100, or 200 ppm Cu as Cu-proteinate, or 250 ppm Cu as CuSO4 (as-fed basis). The basal diets contained 16.5 ppm Cu supplied as CuSO4 before supplementation with Cu-proteinate or 250 ppm Cu as CuSO4. There were quadratic responses (P < or = 0.05) in ADFI and ADG for wk 1, Phases 1 and 2, and overall because ADFI was higher for pigs fed 25 or 50 ppm Cu as Cu-proteinate, and ADG increased with increasing Cu-proteinate up to 50 ppm Cu. The Cu-proteinate treatment groups combined had a higher (P < or = 0.05) Phase 2 and overall ADFI and ADG than the CuSO4 group. In the mineral balance study (Exp. 2), 20 crossbred barrows that averaged 35 d of age and 11.2 kg/BW initially were placed in individual metabolism pens with total urine and fecal grab sample collections on d 22 to 26. Treatments were the basal Phase 2 diet supplemented with 0, 50, or 100 ppm Cu as Cu-proteinate, or 250 ppm Cu as CuSO4 (as-fed basis). Treatments did not differ in growth performance criteria. There were linear increases (P < 0.001) in Cu absorption, retention, and excretion (milligrams per day) with increasing Cu-proteinate. Pigs fed 100 ppm Cu as Cu-proteinate absorbed and retained more Cu and excreted less Cu (mg/d, P < or = 0.003) than pigs fed 250 ppm Cu as CuSO4. Plasma Cu concentrations increased linearly (P = 0.06) with increasing Cu-proteinate. In conclusion, weanling pig growth performance was increased by 50 or 100 ppm Cu as Cu-proteinate in our production Exp. 1, but not in our balance Exp. 2, compared with 250 ppm Cu as CuSO4. However, 50 or 100 ppm Cu as Cu-proteinate increased Cu absorption and retention, and decreased Cu excretion 77 and 61%, respectively, compared with 250 ppm Cu as CuSO4.

Transfer of a rifampicin-resistant Escherichia coli strain among feedlot cattle.

To determine the incidence of transfer of a naturally occurring rifampicin-resistant strain of Escherichia coli (RREC) among cattle in a research feedlot. During three separate experiments, steers in three different pens were orally inoculated with RREC originally isolated from bovine faeces. Faecal swabs were performed on all steers in the feedlot at approximately 5 week intervals thereafter. Faecal grab samples were collected from steers in the inoculated and the immediately adjacent pens for up to 4 months. In all three experiments, the inoculated steers and penmates shed RREC within 48 h, and then shed intermittently throughout the sampling periods. Transfer of RREC to steers in an adjacent pen was confirmed only during the first experiment, but never to those in non-adjacent pens. All recovered RREC isolates were compared with the inoculated strain using multiple methods indicating that all RREC isolates were descendants of the original inoculated strain. Detection of the RREC strain on the pen floor and within the animal handling system, but not in the feed troughs or water bowls, suggests faecal-oral to be the primary mode of transmission among animals. The results suggest that in the absence of selective pressure, antibiotic-resistant bacteria may persist in cattle for a short duration but widespread transfer among cattle in a feedlot environment may be an exception rather than the norm. Modifications to feedlot management are discussed.

Evaluation of n-alkanes as markers for estimation of dry matter intake and digestibility in steers consuming all-forage or forage-concentrate diets

The study examined the reliability of the alkane-based and chromium (Cr)/in-vitro-based procedures relative to the total fecal collection (TC) technique for estimation of dry matter (DM) intake an d DM digestibility of forage or forage-concentrate diets fed to steers. Eight Holstein steers (208 ± 19.2 kg) were assigned to four dietary treatments in a three-period balanced incomplete block design. The four dietary treatments were: (1) 100% meadow brome grass hay (B); (2) 50% B + 50% alfalfa hay (BA); (3) 50% B + 50% barley grain (BB); and (4) 25% B + 25% alfalfa hay + 50% barley grain (BAB). Two types of hay were chosen to achieve a wide range of alkane intake. Appropriate portions of forages and grain were mixed as a total mixed ration and fed in two equal portions twice daily at 2.5% of body weight, DM basis. Two controlled-release capsules, one containing n-alkanes (C32 and C36) and the other chromic oxide, were placed into the steer's reticulo-rumen by oral administration on day 1 of each 30-d period. Total fecal output was collected twice daily from day 8 to 14 of each period to establish the fecal recovery of Cr and the alkanes, and to determine apparent DM digestibility. A rectal fecal grab sample was also taken every 4 h from day 15 to 16. Fecal recovery of the natural alkanes, C31 and C33, was low, ranging from 59.5 to 77.3%, whereas the range in fecal recovery of the dosed alkanes, C32 and C36, was 83.3 to 95.5%, and of Cr was 82.7 to 95.8% across the diets. The estimated DM intake was similar across all diets using the C31/C32 and C33/C32 alkane ratios; however, estimated DM intakes using the alkane method were significantly (P &lt; 0.05) lower compared to TC and Cr/in vitro methods for the BB diet. Addition of barley to the forage diets resulted in a higher DM digestibility for BB and BAB diets by all methods. The estimated DM digestibility using the C31/C32 ratio was lower compared to the TC method for diet B, BA and BB, whereas the estimated DM digestibility using C33/C32 was lower only for the BB diet. Sampling every 4 h resulted in a significantly higher ratio of C 31 to C32 in feces compared to samples collected by the TC method. Rectal grab sampling did not change (P &gt; 0.05) the estimated DM intake using either combination of alkane ratio. Key words: Alkanes, chromium oxide, dry matter intake, dry matter digestibility, steer

Dakota Gold®-brand dried distiller’s grains with solubles in finishing cattle diets: a preharvest strategy against acid resistant Escherichia coli and coliforms? (2002)

Trial 1. Finishing beef heifers (345 head) were used in a 153-day finishing trial to evaluate the effects of feeding six levels of Dakota Gold®-brand dried distiller's grains with solubles (DDGS): 0%, 15%, 30%, 45%, 60%, 75% (dry basis), on the number of acid resistant E. coli and coliforms. Fecal grab samples were taken on day 65 and day 100, 2 and 20 hours after feeding, and were analyzed for acid resistant E. coli and total coliforms, as well as pH and VFA. There was a significant linear increase in fecal pH with increased DDGS at both 2 and 20 hours post-feeding (P<0.05). Total coliforms and acid resistant E. coli at 2 and 20 hours postfeeding were not affected by dietary treatment (P>0.05). Total fecal VFAs were not affected by dietary treatment or hour sampled after feeding (P>0.05) Trial 2. Trial 2 was conducted on ruminally fistulated Jersey steers (18 head) using three levels of DDGS (0%, 30%, 75%). Rumen and fecal grab samples were taken after 4-week adaptation periods on three occasions after every animal had been on each level of the diet and had been sampled. Fecal and rumen samples were taken 2, 4, 6, 8, 12,18, and 24 hours post-feeding. Both fecal and rumen pH were unaffected by dietary treatment, yet an hour effect was noted. Dietary treatment had no effect (P>0.05) on E. coli or total coliforms cultured from rumen fluid or feces.

The use of n-alkane markers to estimate the intake and apparent digestibility of ryegrass and Kikuyu by horses

The n-alkane marker (dosed marker, dotriacontane, C32, herbage markers C31, C33 and C35) technique was evaluated for use in feed intake and digestibility studies with horses. The mean retention time of digesta in the digestive tract was determined in horses following a single dose of C32. The n-alkane technique was then employed to estimate dry matter intake and digestibility in horses fed fresh perennial ryegrass (Lolium perenne), fresh Kikuyu grass (Pennisetum clandestinum, Hochst) and Kikuyu hay. The mean retention time of the C32 marker in the horses was estimated to be 27.9 h. On average the C32 had a slightly greater faecal recovery of 0.89 than the odd-chain alkanes (0.80-0.85), though the differences were not significant. The alkane technique, using the n-alkane markers, gave good estimates of dry matter intake, e.g. for fresh ryegrass the measured intake was 8.86?0.23 kg and the estimated intakes from the C31:C32 ratio, 7.9?1.9 kg and from the C32:C33 ratio, 8.3?1.4 kg. However, the effect of the higher recovery of the dosed marker needs further investigation. The estimates of apparent dry matter digestibility corresponded well with measured values, provided the factor for the incomplete faecal recovery of the internal alkanes was included in the calculation. It was concluded that the alkane technique is suitable to estimate feed intake under grazing conditions. However, the proportion of dietary alkanes recovered in the faeces has to be known to obtain an accurate estimate of apparent digestibility. This would be a problem under grazing conditions when faecal grab samples are taken for measuring faecal alkane concentrations. South African Journal of Animal Science Vol.32(1) 2002: 50-56