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An experiment was conducted to determine the effect of source of pig, housing system and receiving diet on performance of purchased feeder pigs. Pigs purchased from distant auction markets (DM) gained slower for the first 13 d post-arrival (P<.01, trials 1 and 2) than pigs of similar size purchased from local, one-owner sources (LS). In trial 1, LS feeder pigs gained faster (P<.01) from purchase to 93 kg than DM pigs. In trial 2, the DM pigs were more efficient in feed conversion than LS pigs (P<.01). The DM pigs required more medical treatments than LS pigs (P<.01). In trial 1, pigs housed in mechanically ventilated, partially slatted-pen facilities gained faster (P<.1) than those in nonmechanically ventilated facilities whereas in trial 2, the reverse was true (P<.05). Pigs housed in the nonmechanically ventilated facilities had a higher incidence of scours (P<.01, trials 1 and 2) than those housed in the mechanically ventilated facilities. Death loss was less (P<.01) for pigs in the nonmechanically ventilated facilities (trial 2). Pigs fed a 16% crude protein receiving diet for 13 d containing 20% oats had a poorer (P<.01) feed efficiency than those fed a corn-soy basal diet or a diet containing 20% oats plus 5% lard (trial 1). At the termination of both trials, there were no differences in rate of gain or feed to gain ratio between the three receiving diets. Feeding diets containing 20% oats had no effect on the incidence of post - arrival scours but death loss was less (P<.1) for pigs fed the receiving diet containing 20% oats (trial 1).

A completely random design experiment was conducted to determine the effect of dietary arsonic acids on the performance of laboratory swine waste anaerobic digesters. Fortified corn soybean meal diets containing no arsonic acids (control), 100 ppm arsanilic acid or 75 ppm roxarsone were fed to growing-finishing pigs. Fresh waste (including urine) from all treatments were collected daily for 74 days and loaded at a rate of 2.4 kg volatile solids/m3into nine 25-liter anaerobic digesters heated to 34 C with continuous agitation and total gas collection. After a 60-day acclimation period, daily gas production and composition and nutrient composition data were obtained from the anaerobic digesters. Inclusion of the arsonic acids in swine diets reduced dry matter and volatile solids content. Dietary arsonic acids also increased nitrogen in the ammonium form. Alkalinity was high in all the digesters; however, arsonic acids decreased alkalinity. Dietary arsonic acids reduced the ratio of methane to carbon dioxide in the gas compared to the control. Significant amounts of arsenic accumulated in the digesters. Acetic, propionic and butyric acids were increased by roxarsone, and arsanilic acid increased the butyric acid concentration over the percentage in both the roxarsone and control digesters.

Selected microbial organisms were counted in swine wastes during three studies in which the primary objective was to investigate the effects of feed additives and waste management systems on swine waste composition. Dietary salt (NaCl) levels (.2, .5%), dietary arsanilic acid levels (0, 100, 200 ppm), supplemental copper levels (0, 125, 250 ppm) and waste management systems (oxidation ditch, anaerobic deep pit, anaerobic lagoon) were compared in this series of studies. Dietary salt level did not affect total coliform and fecal streptococci concentrations in swine waste. Supplemental copper and arsanilic acid increased total coliform counts (dry matter basis) in anaerobic pit wastes over counts observed with the control. Salmonella sppconcentrations were increased in the anaerobic pit waste at the end of the 104-day feeding trial, especially with the 250-ppm copper diet. Staphylococci spporganisms were not affected by supplemental copper. In all studies, concentrations of the microorganisms cultured were higher in freshly excreted waste than in waste stored and partially treated in the waste systems studies. Temperature, dilution and waste handling systems had some effects on microbial populations

In four trials, steer calves were received in the feedlot, processed and fed diets supplemented with soybean meal (SBM), 1% urea (UR) or 1% urea plus sarsaponin (S) over a 28-d period. In trials 1 and 2, the feeding period was extended to approximately 62 d, in which steers were fed a common (SBM) diet the last 34 d. In trials 3 and 4, a SBM plus S diet treatment was included. During the first 28 d (four trial summary) daily gains of steers fed urea plus S (.74 kg) were intermediate to and significantly different from gains of steers fed SBM (.84 kg) or UR (.66 kg) diets. However, at the end of the 62-d feeding period (two trial summary) daily gains, feed intakes and feed efficiency did not differ (P>.05) among treatments. No significant improvements in performance were found in steers fed SBM diets supplemented with S. In swine trials, pigs were fed diets containing no additive, 63 mg S·kg−1, 55 mg Chlortetracycline (C)·kg−1or S plus C in a grower-finisher (GF) and grower (G) trial. In the GF trial, overall efficiency of feed conversion was improved (P<.05) by feeding S or S plus C. In the G trial, daily gains and intakes were greatest for pigs fed S plus C and differed (P<.1) from those of pigs fed S or C in the diet. Compared with feeding S or C alone, gain and intake of growing pigs were stimulated to a greater extent when S was fed in combination with C. Feeding S with or without C improved efficiency of feed conversion in finishing pigs.

Two experiments were conducted to determine the effects of feed and water restriction and receiving diet crude protein level on feeder pig performance. In Exp. 1, a total of 239 commingled feeder pigs transported over 1,000 km were used in two trials. Pigs given access to feed and water (FW) at the market weighed more (P<.0001) following marketing and transport than pigs given no feed and water (N) for the comparable 25-h market period (20.7 vs 19.6 kg). While FW pigs weighed less (P<.02) than N pigs at the conclusion of the trials (93.9 vs 96.6 kg), there was no effect (P>.1) on overall average daily gain (.32 vs .35). There were no effects of receiving diets containing 12, 16 or 20% crude protein on daily gain, daily feed intake or feed efficiency for the overall growing-finishing period. Scour scores on d 8, 9, 10, 11, 13 and 14 post-arrival increased (P<.01) with increased levels of protein in the receiving diets. In Exp. 2, a total of 360 crossbred feeder pigs was mixed and moved from a nursery to grower-finisher facilities in three trials, given feed and water access immediately (FWG) or denied access for 44 h (NG). At the end of the 44-h period, FWG pigs were heavier than NG pigs (P<0001; 18.3 vs 16.7 kg). There was no treatment effect on overall pig weight, daily gain or feed efficiency.

Three experiments of 5 wk duration were conducted to evaluate the effect of reduced nocturnal temperatures (RNT) on weaned pig performance. Treatments were 1) a control regimen (CR) of 30 C constant air temperature lowered 2 C/wk and 2) a regimen where the temperature from 1900 to 0700 h was lowered to 25 C for three nights followed by 20 C for four nights during the first week and then lowered 1 C/wk thereafter (RNT). Weaned pigs averaging 23 ± 2 d of age at the start of the experiments gained faster (P<.0J) in the RNT treatment vs the CR treatment in Exp. 1, 2 and 3, respectively (.32 Vs .28; .39 vs .37; .35 vs .34 kg/d). The improvement in gain was accompanied by an increase (P<.005) in feed intake for the same period (.48 vs .44; .61 vs .55; .58 vs .54 kg/d). There was no difference in feed conversion. Weaned pigs that were 1.9 to 2.3 kg lighter initially gained slower (P<.0005) compared with their heavier contemporaries (.27 vs .33; .33 vs .43 and .31 vs .33 kg/d) in Exp. 1, 2 and 3, respectively. This reduced gain was accompanied by a reduced (P<.0005) feed intake (.40 vs .51; .50 vs .66; .50 vs .62 kg/d). There was no interaction of initial weight and temperature regimen.

Four trials were conducted with 1,480 pigs (initial wt: 23 kg in trial 1, 29 kg in trial 2 and 49 kg in trial 3 and 4) to determine the effect of dietary fat on pig performance, nutrient separation in an automated feed distribution system, dust levels in swine buildings and integrity of the respiratory system of swine. Two modified-open-front (B-1 and B-2) and two environmentally regulated (E-1 and E-2) growing-finishing buildings, of identical design, were used in each trial. In trial 1, 250 pigs (25 pens of 10 pigs/pen) in B-l were fed a ground, mixed, corn-soybean meal diet (15% crude protein) with added tallow (5%), and 250 pigs in B-2 were fed the same diet but without added tallow. The assignment of diets to buildings were reversed in trial 2 in which 2.5% tallow was used instead of 5%. Each diet was fed ad libitum to pigs, and was distributed by an automated “Flexauger” system in trials 1 and 2. In each of trials 3 and 4, 120 pigs (12 pens of 10 pigs/pen) in E-1 were fed a corn-soybean meal diet (14% crude protein) with added tallow (5%) and 120 pigs in E-2 were fed the same diet but without added tallow. Overall, pigs fed the diet with tallow gained faster (P<.002), consumed less feed (P<.02) and converted feed more efficiently (P<.002) than those fed the diet without tallow in trials 1 and 2. Pig performance was also improved by the addition of tallow to the diet in trials 3 and 4 (P<.002). Crude protein, Ca, P and Cu contents of both diets were similar at each location sampled throughout the automated distribution system in trials 1 and 2. Addition of tallow to the diets reduced aerial dust levels, both with the feed distribution auger running (P<.002) and without the auger running (P=.06) in trials 1 and 2. In trials 3 and 4, adding 5% tallow to the diet reduced aerial dust concentrations of particle sizes of 14, 4, and 1.5 μm (P<.002) and .4 μm (P=.07). The amount of settled dust was lower (P<.001, trials 1, 3 and 4) when tallow was included in the diet. There was no difference between the two dietary treatments in the incidence of abnormal turbinates in all four trials. There was a trend for pigs fed the diet without tallow to have more severe forms of lung lesions than those fed the diet with tallow in trials 1 and 3. The results of microscopic examination and crude protein analysis of settled dust indicated that the swine-house dust was mainly feed dust.

Three experiments were conducted to determine the effect of receiving diets containing alfalfa meal and certain feed additives on performance of comingled feeder pigs transported 900 to 1,100 km. In Exp. 1, the inclusion of 9.4% dehydrated alfalfa meal in receiving diets for 2 wk resulted in no difference (P>.1) in gain or feed conversion from purchase to market compared with pigs fed a basal corn-soybean meal (CS) diet or a diet containing 20% ground whole oats (O). In Exp. 2, pigs fed receiving diets containing 10% dehydrated alfalfa meal had no improvement (P>.1) in gain (.60 vs .61 kg/d) or conversion (3.25 vs 3.17) compared with CS-fed pigs. In Exp. 3, pigs fed a receiving diet for 2 wk containing 10% mid-bloom alfalfa ate more (P<.002) feed daily for 2 wk (.82 vs .76 kg) and overall (P<.04; 1.92 vs 1.85 kg) and had an improved (P<.03) daily gain from purchase to market (.61 vs .59 kg) compared with CS-fed pigs. In Exp. 2, pigs fed diets containing 44 mg/kg tylosin (T) gained similar to pigs fed no additive (O) and slower (P<.01) than pigs fed 110 mg/kg Chlortetracycline (CTC; .59, .60 and .63 kg/d), with no significant differences in feed to gain conversion (3.12, 3.23 and 3.18). Pigs fed CTC gained faster overall (P<.04) than did pigs fed 55 mg/kg bacitracin methylene disalycilate (BMD) or the unsupplemented control diet in Exp. 3 (.62, .59 and .58 kg/d), while CTC- and BMD-fed pigs improved (P<.02) in feed conversion (3.11, 3.11 and 3.26). In each experiment, the inclusion of alfalfa meal resulted in a reduction in scours for several days immediately post-arrival. Pigs fed CTC had less scours from d 8 to 14 post-arrival than did the control, T- and BMD-fed pigs. There was no difference (P>.1) in pig death loss in any of the experiments due to experimental treatments.

An experiment was conducted to determine the effect of copper sulfate in swine diets on fresh waste composition and on decomposition of the waste stored in anaerobic pits. Vitamin and mineral fortified corn-soybean meal diets with 0, 125 and 250 ppm copper were fed to growing-finishing pigs (18 to 91 kg) in spring and summer trials with daily fresh waste collection and addition to anaerobic pits.Copper concentrations (wet basis) in the anaerobic pits from pigs fed the 0, 125 and 250 ppm copper diets for trial I were 3.15, 34.27 and 44.63 ppm, respectively. For trial II, copper concentrations were 3.55 and 48.61 ppm, respectively, for diets containing 0 and 250 ppm copper. Average elemental copper excretion for the 250 ppm copper diets ranged from 433 to 490 mg per head per day.The presence of copper sulfate in swine diets did not affect fresh waste composition. Copper sulfate decreased the decomposition of the waste in anaerobic pits as shown by the greater reduction of dry matter and volatile solids in waste from pigs fed no copper sulfate. Dry matter content was reduced 65% in anaerobically stored waste from pigs fed 0 ppm copper, while the dry matter content was reduced only 55 and 51% from pigs fed the 125 ppm and 250 ppm copper diets in trial I. In trial II the dry matter was reduced 41% for the 0 ppm stored waste and 31% for the 250 ppm stored waste.

A complete random design experiment was conducted to determine the effect of dietary arsonic acids on swine waste composition and decomposition in anaerobic pits. Vitamin and mineral fortified corn-soybean meal basal diets with either 75 ppm roxarsone or 100 ppm arsanilic acid were fed to growing-finishing pigs (14 to 91 kg) with daily fresh waste collection and addition to model anaerobic pits.Arsonic acids in the diet influenced (P<.001) pH, dry matter, volatile solids, Kjeldahl nitrogen, ammonium nitrogen and arsenic content in the model anaerobic pits. Compared to the control there was a significant decrease in dry matter and volatile solids. Arsanilic acid in the diet increased (P<.001) the amount of nitrogen in the ammonium form compared to the control and roxarsone diet. Arsanilic acid increased (P<.05) the acetic acid content in the anaerobic pit compared to the control when expressed as a percentage of total volatile fatty acids measured.Elemental arsenic losses to the atmosphere were measured in anaerobically stored waste from all treatments.

A complete random design experiment was conducted to determine the effect of arsanilic acid in swine diets on fresh waste production and composition and on decomposition of the waste stored in anaerobic pits. Vitamin and mineral fortified corn-soybean meal diets with 0, 100 or 200 ppm arsanilic acid were fed to growing-finishing pigs (14 to 91 kg) in winter and summer trials with daily fresh waste collection and addition to anaerobic pits.Average daily total waste production (wet basis) per pig, including hair, dust, wasted feed, waste water and excreta, was 3.8 kg during the winter trial and 4.8 kg during the summer trial. Average elemental arsenic excretion ranged from 35.7 mg to 62.8 mg per head per day. Arsenic concentrations (wet basis) in the anaerobic waste from pigs fed the 0, 100 and 200 ppm arsanilic acid diets for both trials were .54, 6.29 and 11.23 ppm, respectively.The presence of arsanilic acid in swine diets did not affect fresh waste production or composition. Arsanilic acid did enhance the decomposition of waste as shown by the reduction of dry matter and volatile solids in waste from arsanilic acid fed pigs. Dry matter content was reduced more than 60% in each trial in anaerobically stored waste from pigs fed arsanilic acid, while the dry matter content was reduced 23% and 39% in the waste from pigs fed the control diet. The presence of arsenic in the waste resulted in the retention of more total nitrogen (dry basis) and nitrogen in the ammonium form compared to waste with no arsenic but did not affect phosphorus, potassium and nitrate nitrogen levels.

A four-trial experiment utilizing 3- to 4-wk-old newly weaned pigs was conducted to evaluate the effect of a modified reduced nocturnal (MRNT) nursery temperature regimen on weaned pig and subsequent grower-finisher performance. Nursery treatments were 1) a control temperature (CT) regimen of 30°C constant air temperature lowered 2 C°/wk and 2) a regimen beginning 1 wk after weaning in which the temperature from 1900 to 0700 was lowered 6°C from CT. Weaned pigs gained faster (P< .01) in the MRNT treatment than in the CT treatment, with gains in Trials 1, 2, 3 and 4 being .39 vs .37, .28 vs .27, .38 vs .37 and .39 vs .36 kg/d, respectively. This improvement in gain was due to an increase (P< .005) in feed intake for the same periods (.60 vs .58; .48 vs .42; .59 vs .58; .63 vs .58 kg/d). There was no difference in feed conversion (P> .1). There was no effect (P> .1) of MRNT vs CT on subsequent performance to slaughter weight for average daily gain (.69 vs .69 kg/d), average daily feed (2.22 vs 2.23 kg/d) or gain/feed (.31 vs .31). These results support the conclusions that weaned pigs eat more feed and gain faster with a reduced nocturnal temperature scheme and that there are no carry-over effects during the growing-finishing phase.

A total of 288 commingled crossbred feeder pigs were purchased and transported 1,050 km in two trials to investigate the effect of added dietary potassium chloride in receiving and finishing diets on feeder pig shrink recovery, performance and pre-slaughter shrink. Diets containing 0, .48%, .96% or 1.44% added potassium chloride were fed for 2 wk post-arrival and again from 12 wk post- arrival until slaughter. There was no effect (P> .1) on gain (22.9 kg pay weight) or feed conversion or on plasma or red blood cell potassium for the 2-wk post-arrival period due to the inclusion of potassium chloride in the 2-wk receiving diet. Also, there was no effect (P> .1) of potassium chloride in diets from 12 wk post-arrival until slaughter on gain, feed conversion, market shrink, carcass dressing percentage and plasma or red blood cell potassium concentration at slaughter. These results suggest that corn-soybean meal-based diets contain sufficient potassium for pigs following a period of stress associated with marketing and transport.

An experiment was conducted to determine the effects of 1) long-acting oxytetracycline injection at market arrival, 2) feed or water access at the auction market and 3) receiving diet management on commingled feeder pig performance. A total of 288 commingled feeder pigs transported over 1,000 km after market management treatments were used in two trials. Pigs given access to feed and water (FW) at the market weighed more (P< .001) following marketing and transport than pigs given water only (W). Pigs given neither feed nor water (N) were intermediate in arrival weight (19.7, 18.7 and 18.9 kg). There was no effect (P> .1) of feed and water offering at the market on final weight (96.6, 95.9 and 96.6 kg), overall average daily gain (.70, .69 and .70 kg/d), overall gain/feed (.31, .31, .32) or percentage death loss (1.0, 2.1 and 4.2%). Injection of long-acting oxytetracycline upon arrival at auction market had no effect (P> .1) on pig weight following marketing and transport (19.0 vs 19.2 kg), final weight (96.1 vs 97.0 kg), percentage death loss (3.4 vs 1.4%) or percentage of pigs treated (3.4 vs 4.9%). Compared to providing ad libitum access to feed, restricting feed intake by floor feeding for the first 7 d post-arrival reduced (P< .01) rate of gain for the first 9 d (−.04 vs .08 kg/d), but overall there was no effect (P> .1) on daily gain (.70 vs .69 kg/d) or gain/feed (.31 vs .31).