Effects of daily porcine somatotropin administration on tile performance and carcass characteristics of finishing swine

One hundred forty-four pigs (72 barrows and 72 gilts) were utilized in six treatments with six pens each to evaluate four levels of daily porcine somatotropin (pST) injections (0, 1, 3, or 5 mg/d) in combination with diets containing 13 or 16% crude protein (CP). One randomly selected pig from each pen was slaughtered when it reached a weight between 230 and 240 lb. Daily feed intake (ADFI), tenth rib backfat, and estimated percentage of lean pork were reduced in pigs fed the 13% CP diet and injected with 3 mg/d pST compared to pigs fed the same diet and injected daily with a placebo. Feed intake was reduced in pigs fed the 16% CP diet and injected daily with 3 and 5 mg/d pST. Improvement in feed conversion (F/G), tenth rib backfat, and estimated percentage lean pork occurred when pigs fed the 16% CP diet were injected with 1 mg/d, with greater improvements occurring at the 3 and 5 mg/d levels of pST. The improvement in F/G and the greater magnitude of response observed in pigs fed 16% CP diets compared to the response of pigs fed the 13% CP diet indicate that both the performance and carcass characteristics of pigs injected with pST are dependent on the dietary CP content

Sunflower oil seeds in nursery pig diets

Two hundred forty pigs were used to evaluate the use of various amounts (0, 10, 15, 20, 25%) of black sunflower oil seeds in weanling pig diets. After 14 days, no significant differences were found between any of the dietary treatments in feed intake (FI), average daily gain (ADG), or feed efficiency (F/G). At the conclusion of the 5-wk study, no differences were found in FI, ADG, or F/G between those dietary treatments containing 0, 10, and 15% sunflower seeds. However, in those diets containing 20 and 25% sunflower seeds, there were linear (p<.05) reductions in FI and ADG. These results indicate that sunflower seeds, when finely ground using a hammermill with a 1/8 in screen, can be used in diets for weanling pigs up to 15% of the diet with no reduction in performance

Sustained effects of porcine somatotropin administered during the growing period on growth and carcass characteristics of finishing pigs

Forty six barrows were fed a common diet after completing a 35 d growth trial in which 50% received 5 mg/d of pST and the other 50% a placebo injection. At the conclusion of the growing trial (130 lb), the pST-injected pigs were leaner (22%) and yielded carcasses with larger longissimus muscle area (21 %). However, pigs fed to a slaughter weight of 225 lb yielded carcasses that were not different from control pigs in length, longissimus muscle area, or belly weights. Pigs administered pST during the growing phase continued to have 10% less backfat, which resulted in a 1.6% greater yield of lean cuts. Postinjection growth rate of pST-treated pigs was significantly reduced for the initial 2 wk to cause an overall reduced ADG during the finishing period. Days to reach slaughter did not differ with treatment because those pigs previously receiving pST were heavier initially. There is no advantage to injecting pigs with pST during the growing phase to improve overall growth. However, pST administration during the growing phase appears to have a sustained effect on carcass fat thickness of pigs slaughtered at 225 lb

Evaluation of oral escherichia coli bacterin and water medication on performance of weaned pigs

Odd-numbered pigs in new-born litters were vaccinated on d 1 with an oral Escherichia coli bacterin and their performance after weaning was compared with that of nonvaccinated littermates (even numbered pigs). In addition, each group of pigs was allotted to four water medication treatments that were administered from d 2 to d 6 after weaning. No significant interaction between vaccine and water treatment was observed. Vaccinated and non-vaccinated pigs performed similarly throughout the trial for the traits of ADG, ADFI, and F/G, indicating no beneficial effect from vaccination. Water medication after weaning did not affect performance or incidence of scours during the first 14 d. During the next 16 d of the trial, those pigs that had not received water medication grew faster and were 8% more efficient than those that received the Apralan and Genotocin water medications. Overall performance (0 to 30 d) was similar among all water treatments (non-medicated, Apralan, Genotocin, and Neomycin) for the traits of ADG and ADFI. The most efficient pigs were the non-medicated. The incidence of scours was similar for all treatments, except those medicated with Apralan, which had greater incidence

Effect of diet particle size on utilization of sunflower oil seeds in nursery pig diets

One hundred ninety-two weanling pigs were fed diets containing 15 or 25% sunflower oil seeds that were ground using a hammermill equipped with either a 1/8 or 3/16 in. screen. Average daily gain (ADG) of pigs fed the 25% sunflower seed diet ground through a 1/8 in. screen was similar to ADG of pigs fed the control diet or that with 15% sunflower seeds, although there was a reduction in ADFI. This indicates that finely ground sunflower seeds can be utilized in nursery pig diets up to 25% with no impairment in performance

Space requirements of finishing pigs fed to a heavier weight (removed individually)

Space allowances of 6, 8, 10, and 12 ft2 were evaluated for pigs fed from 120 to 250 lb. The management system used was to remove pigs individually as they reached 250 lb, which provided increasing space per pig. Using this management system, average daily gain, average daily feed intake, and feed effeciency improved linearly with increasing space allowance. Pigs allowed 6ft2 gained slower, ate less, and required more feed per lb of gain compared to pigs allowed 8, 10, and 12 ft2. Pigs permitted 8, 10, and 12 ft2 were similar in rate of gain, feed consumption, and feed efficiency, suggesting that 8 ft2 is adequate space for the finishing pig, if pens are topped out as pigs individually reach 250 lb. If pigs are fed to a pen average of 250 lb without removing pigs individually, 10 ft2 is required to maximize performance, as reported in Report of Progress 581. In this trial, space allowance of 6 ft2/pig impaired pigs performance from 120 to 200 lb. These results have been observed in previous studies, suggesting that finishing pigs need a minimum of 8ft2 in the finishing phase

Postfinishing mineralization of skeletal tissue in replacement gilts

Thirty-two crossbred gilts averaging 250 /b were selected for the experiment at the conclusion of the finishing phase. Eight of the gilts were slaughtered on d 0 to serve as a pretreatment control group. The remaining 24 gilts were assigned to three dietary treatments to provide daily 100% (14 g/d Ca and 11.3 g/d P), 150% (22.5 g/d Ca and 16.6 g/d P), and 200% (29.9 g/d Ca and 22.0 g/d P) of the Ca/P level consumed per d during the finishing phase. These gilts were slaughtered 35 d later at 291 lb. Gilts receiving 29.9 g/d Ca and 22.0 g/d P yielded ribs that had the highest values for percent ash, bending moment, and modulus of elasticity. Femurs did not differ in any bone characteristics because of treatment; however, the 3rd metacarpal bone showed the highest percent ash and greatest bending moment at the intermediate level of Ca/P

Effect of fat combinations on starter pig performance and nutrient digestibility

A growth trial was conducted to evaluate the effects of addition of soybean oil, coconut oil, 50% soybean oil: 50% coconut oil, 75% soybean oil: 25% coconut oil, and 25% soybean oil: 75% coconut oil on starter pig performance and nutrient digestibility. Diets were supplemented with 10% fat for the first 2 wk of the study and 5% for the final 3 wk. Fecal samples were collected from pigs by rectal massage, and apparent digestibility of DM, N, total fat, and fatly acids were calculated using chromic oxide (.3%) as an indigestible marker. Results demonstrated that ADG and feed efficiency (F/G) were improved by fat additions, with 50% soybean oil and 50% coconut oil maximizing performance. Pigs gained faster on the soybean oil and coconut oil combinations than on coconut oil and consumed more of the soybean oil plus coconut oil diet than either coconut oil or soybean oil diets. No differences were observed for apparent digestibility of fat and GE or ileal digestibility of DM and N among the fat sources. However, pigs fed the combination of soybean oil and coconut oil tended to have improved ileal digestibility of medium chain fatty acids (< 14 C). These trials demonstrate that a combination of soybean oil and coconut oil improves pig performance and tends to improve apparent digestibility of medium chain fatty acid compared to pigs fed diets containing either no added fat or soybean oil or coconut oil alone

Effect of L-carnitine on starter pig performance and fat utilization

Three hundred early-weaned pigs with average initial weights of 12.3 and 13.2 lb, respectively, were utilized in two 5-wk experiments to determine the effect of L-carnitine on growth Performance. Diets contained 20% dried skim and 20% dried whey in phase 1 ( 0 to 14 d) for both experiments and 20 and 10% dried whey, respectively for experiments 1 and 2 in phase 2 (15 to 35 d). In experiment 1, L-carnitine at levels of 0, 500, and 1000 ppm was combined with 0 or 10% soybean oil in phase 1, levels were reduced by 50% in phase 2 to 0, 250, and 500 ppm L-carnitine and 0 or 5% soybean oil. There was no improvement in pig performance from addition of either L-carnitine or soybean oil in phase 1. In phase 2 and for the cumulative 5 wk experiment, soybean oil addition improved average daily gain (ADG) but had no effect on feed intake (Fl) or feed/gain (F/G). Feed efficiency was improved linearly as the level of L-carnitine was increased in phase 2, however, there was no effect on ADG or Fl. In experiment 2, L-carnitine levels in phase 1 were 0 and 1000 ppm, combined with levels of 0, 250, and 500 ppm in phase 2. Addition of L-carnitine improved ADG and increased FI, but had no effect on F/G the first 2 wk postweaning. In phase 2, increasing the level of L-carnitine resulted in improved F/G. Feed intake was decreased as L-carnitine level increased. There was no effect on ADG in phase 2 or during the cumulative 5 wk experiment from level of L-carnitine fed. Feed efficiency improved and FI decreased over the 5 wk trial as the level of L-carnitine increased. Based on the results of these experiments, addition of L-carnitine shows the potential to improve F/G by 11 to 16% in phase 2 and 7 to 9 % for the overall starter phase

Effect of roasting on utilization of sunflower oil seeds in nursery pig diets

One hundred twelve weanling pigs were used to evaluate effects of diets containing 25% raw or low or high roasted sunflower seeds on performance. Pigs fed meal and pelleted diets containing sunflower seeds roasted to a roaster exit temperature of 264 of (low roast) were more efficient (F/G) than pigs fed raw sunflower seed diets in meal form. Pelleting raw, low roast, and high roast sunflower seed diets significantly improved F/G compared to raw sunflower seed and basal diets fed in meal form. These results indicate that meal diets containing 25% low roasted sunflower seeds or pelleted diets containing 25% raw or low roasted sunflower seeds can be fed to weaned pigs with no reduction in performance