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PubMed2003

Effect of dietary rare earth elements on growth performance and blood parameters of rats.

Rare earth elements (REE) have been shown to influence growth performance in animal production, especially in pigs. In the present study, the effect of oral administration of rare earth elements on growing rats was investigated. Pure LaCl3 or an REE mixture containing 38% of LaCl3, 52% of CeCl3, 3% of PrCl3 and 7% of chlorides of other REE were used at two different concentrations as supplements to the diets. Fifty male Wistar rats at 4 weeks of age were allotted to five experimental groups: a control group; a La-low group and a La-high group with 75 and 150 mg/kg LaCl3.6H2O, respectively; a REE-low and an REE-high group with 75 and 150 mg/kg REE mixture, respectively. The animals were housed in individual pens. Feed and water were provided ad libitum. After 18 days the oral supplementation of LaCl3.6H2O or of the REE mixture improved daily body weight gain (BWG) by up to 5 or 9% (p > 0.05), respectively. LaCl3.6H2O as well as the REE mixture had positive effects (p < 0.05) on feed conversion ratio (FCR) with a decreased ratio by up to 8 and 11%, respectively. Supplementation of REE also had clear effects on blood serum parameters. The activities of alkaline phosphatase (AP) and alanine amino transferase (ALT) increased significantly (p < 0.05). At the same time, blood glucose level decreased and blood creatine level increased significantly (p < 0.05). There was no significant difference in cholesterol, total protein, albumin and urea nitrogen among the groups. There was no significant difference in triglyceride level between the control and those REE groups, however, a significantly lower (p < 0.01) triglyceride level was found in the 150 mg/kg REE mixture group compared with that in 75 mg/kg REE mixture group and the 150 mg/kg LaCl3.6H2O group. The results suggest that oral supplementation of REE improves growth performance in rats as in pigs. In this respect, concentration and type of REE supplemented to the diets are two important factors herein.

Administration, Oral↗

PubMed2000

Chromium yeast affects growth performance and plasma traits but not carcass characteristics of growing-finishing pigs depending on the glycemic index.

Forty Swiss Large White pigs (barrows with 31.7 kg initial to 103.7 kg final BW) were equally and randomly assigned to one of four treatments (H0, H200, L0, L200) involving a combination of chromium supplementation (0 or 200 micrograms/kg) and glycemic index (high GI (H) or low GI (L)). Growth performance, energy and protein digestibility, carcass composition, and some plasma traits were investigated. The data indicated, that the substitution of dietary carbohydrates with fat and crude fibre (low GI) resulted in lower growth performance due to impaired energy digestibility. Moreover, the strong stimulation of insulin secretion due to the high and rapid availability of carbohydrates of the diets H0 and H200 caused increased carcass fat deposition. Chromium supplementation also affected plasma insulin and glucagon concentrations. Depending on glycemic index, chromium affected the growth performance. Daily gain was reduced in pigs of the L200 treatment compared to the L0 group. This finding indicated that the energy availability expressed as GI is one of several nutritional factors, which determine the efficacy of dietary chromium. We could not corroborate evidences that dietary chromium modifies the chemical composition of the whole carcass, but depending on GI, chemical composition of the longissimus muscle was affected.

Animal Feed↗

PubMed1991

Influence of time of injection of recombinant porcine somatotropin (rpST) relative to time of feeding on growth performance, hormone and metabolite status, and muscle RNA, DNA, and protein in pigs.

Thirty-six barrows were used in a 2 X 3 factorial treatment array to determine the effects of time of injection (0800 [AM] or 1800 [PM]) of recombinant porcine somatotropin (rpST) (0, 50, or 100 micrograms.kg BW.d-1 adjusted weekly) relative to time of feeding on growth performance, carcass composition, serum hormones and metabolites, and muscle RNA, DNA, and protein. Pigs were fed at 85% of ad libitum and allowed access to feed between 0800 and 1200. Treatments were initiated at 38 kg and continued until each pig consumed an average of 7.5 Mcal of DE/d. There was no significant effect of injection time for any measure of growth performance or composition of gain even though rpST treatment improved most criteria evaluated. Treatment with rpST increased ADG by 30%, improved feed:gain by 23%, reduced lipid accretion by 46%, increased protein accretion by 69%, and increased loin eye area (LEA) by 26%. Time of injection also had no effect on serum hormones or metabolites, except for nonesterified fatty acids (NEFA), which were 20% higher in the AM-injected animals. Treatment with rpST increased (P less than .05) RNA concentration (21%) and RNA/DNA (17%) in longissimus dorsi (LD) muscle. In semimembranosus (SM) muscle, however, rpST administration resulted in an increased (P less than .05) DNA concentration (10%) and a decreased DM content (4%). These results suggest that rpST influences growth differently in these two muscles. We conclude that time of rpST administration (AM vs PM) has no effect on its metabolic properties and, therefore, no effect on growth performance in the pig.

Adipose Tissue↗

PubMed2001

Impact of iron supplementation and deworming on growth performance in preschool Beninese children.

OBJECTIVE: To assess the effects of iron and deworming on linear growth performance of preschoolers. DESIGN: Three-month randomized, double-blind and placebo-controlled trial. The children were allocated to four treatments: iron (60 mg elemental iron/day) + albendazole (200 mg/day for 3 consecutive days, repeated 1 month later), iron + albendazole-placebo, albendazole + iron-placebo or placebos. The supplementation was supervised. SUBJECTS: A group of 177 children aged 3-5 y was selected from low-income households in a rural area in southern Bénin. A complete data set was analysed for 140 subjects. Many children were stunted (58% had height-for-age Z-score <-2), none were wasted (2% had weight-for-height Z-score < -2) and 76% were anemic (Hb < 110 g/l). MAIN OUTCOME MEASURES: Anthropometric parameters, hemoglobin and eggs per gram feces. RESULTS: No significant difference in changes in anthropometric parameters was observed between study groups, and also not in a sub-sample of stunted and anemic subjects. Changes in hemoglobin were highest in the iron-treated subjects at the end of the 3-month intervention period (P = 0.032). The difference between the iron and the placebo groups remained significant even 7 months later (P = 0.022). The difference was 5 g/l in both periods. Ascaris lumbricoides and hookworm infections decreased significantly in albendazole-treated subjects (P < 0.05). CONCLUSIONS: In addition to recurrent parasitic infection burden, the children may have multiple micronutrient deficiencies. Therefore, it may be interesting to study appetite and food intake of young toddlers in relation to health and linear growth performance in poor environments.

Albendazole↗

PubMed1995

Effects of dietary buffers on growth performance, nutrient digestibility, and stomach morphology in finishing pigs.

The effects of supplemental alkaline salts on growth performance, blood chemistry, and stomach morphology were determined in two experiments using 248 finishing pigs fed finely ground diets. In Exp. 1, 128 pigs (56 kg average initial BW) were fed a corn-soybean meal-based diet (488-microns mean particle size) for 66 d. Treatments were control and 1, 2, or 3% added NaHCO3 in a randomized complete block design. Average daily gain (linear effect, P < .005), dressing percentage (linear effect, P < .04), and plasma urea N concentration (linear effect, P < .004) decreased as the concentration of NaHCO3 in the diet was increased, but primarily at the 2 and 3% additions. Feed intake, gain/feed, backfat thickness, stomach ulceration score, blood gases (pCO2 and HCO3), and plasma Na and K were not affected by treatment (P > .11). In Exp. 2, 120 pigs (55 kg average initial BW) were fed a pelleted wheat-soybean meal-based diet (355-microns mean particle size) during a 64-d growth assay. Treatments were 1) control, 2) 1% NaHCO3, and 3) 1% KHCO3. Average daily gain, ADFI, gain/feed, backfat thickness, stomach keratinization score, blood pCO2, plasma urea N, and digestibilities of DM and N were not affected by treatment (P < .15). However, addition of NaHCO3 and KHCO3 tended to decrease (P < .10) the incidence of ulcers and increased (P < .05) the concentration of blood HCO3- and digestibility of GE. These data indicate that 1% addition of either NaHCO3 or KHCO3 may help to reduce the severity of gastric ulcers in finishing pigs without adversely affecting growth performance or nutrient digestibility.

Animal Nutritional Physiological Phenomena↗

PubMed2003

Effect of restricted postweaning growth resulting from reduced floor and feeder-trough space on pig growth performance to slaughter weight in a wean-to-finish production system.

The effect of reduced pig growth rate postweaning as a result of restricted floor space and feeder trough space on subsequent growth to slaughter was investigated in a wean-to-finish system. Crossbred pigs (n = 1,728) were used in a randomized block design with a 2 x 2 x 2 factorial arrangement of treatments: 1) floor space (high [0.630 m2/pig] vs. low floor space [0.315 m2/pig]), 2) feeder trough space (unrestricted [4 cm/pig] vs. restricted feeder trough space [2 cm/pig]), and 3) period of imposing floor- and feeder-trough-space treatments (12 vs. 14 wk postweaning). Growth performance was measured from weaning (5.5 +/- 0.01 kg of BW; 17 d of age) to slaughter (the end of wk 25 postweaning). From the end of the treatment period to the end of wk 25, pigs on all treatments had the same floor and feeder trough space. Pigs with low floor space had lower (P < 0.01) ADG, ADFI, and gain:feed ratio than those with high floor space, and were therefore lighter (P < 0.05) at the end of the postweaning treatment period. Pigs given the restricted feeder trough space had lower (P < 0.05) ADFI, similar (P > 0.05) ADG, and higher (P < 0.01) gain:feed ratio than those with unrestricted feeder trough space during the treatment period. Pigs in the 14-wk treatment period had higher (P < 0.01) ADG and ADFI, but lower gain:feed than those in the 12-wk treatment during that period. In the subsequent period, from the end of treatment to wk 25, there was an interaction (P < 0.05) between floor space and treatment period; the difference in ADG and gain:feed for pigs on low vs. high floor space was greater for the 14-wk than the 12-wk treatment period. However, low-floor-space pigs tended (P = 0.06) to be lighter than high-floor-space pigs at the end of wk 25 postweaning. Neither feeder trough space nor treatment period affected pig growth performance during the period from the end of treatment to wk 25. Carcass backfat and longissimus depths at the end of wk 25 were not influenced (P > 0.05) by treatment. In summary, pigs with restricted growth due to low floor space until either 12 or 14 wk postweaning had increased growth and feed efficiency in the subsequent period to wk 25 postweaning, with only a slight effect on BW and no effect on carcass measures.

Adipose Tissue↗

PubMed1990

Effect of nematode infections and management practices on growth performance of calves on commercial dairy farms.

Liveweight of calves on 86 dairy farms was measured at the end of the grazing season and related per herd to the level of exposure to nematode infection estimated in October and December. There were significant between-herd variations in all the serological infection parameters measured. On average 20.5 larvae per gram faeces (geometric mean) were found in October. Faecal samples of 20.5% of the herds contained lungworm larvae. Liveweight of calves deviated per herd from -59.8 kg to +52.2 kg from an age-adjusted population mean after their first grazing season. Growth performance was significantly related negatively to several serological and parasitological parameters. Data were fitted by means of both linear and segmented curvilinear regression. By combining infection parameters 19% of the variation in growth performance among herds could be explained. Infection parameters involved were antibody titre against Cooperia spp., egg output and lungworm larval count. It was found that antibody titres were significantly correlated positively to herd age, while pepsinogen values and egg output were negatively correlated to age. Combining supplementary feeding and anthelmintic treatment during the grazing season with the infection parameters into one model explained approximately 30% of the observed variation in growth performance among herds. It was shown that these findings were consistent with those of a similar study conducted on the same farms a year earlier, although there were clear differences between the years. Finally, significant positive relations were found between the levels of exposure to nematode parasites within farms between two consecutive years.

Age Factors↗

PubMed1997

Comparison of growth performance and nutrient retention of weaner pigs given diets based on casein, free amino acids or conventional proteins.

In two experiments the potential value of diets based on casein or free amino acids (FAA) for amino acid utilization experiments were examined. In Expt 1 the optimum dietary electrolyte balance (dEB) for a casein-based diet was estimated by supplemention with 10 or 20 g NaHCO3/kg, to produce diets containing 64, 183 or 302 mmol/kg. In addition, piglet growth performance and efficiency of nutrient deposition of piglets given the casein diets were compared with two multiple protein source diets; Supercreep, a commercial multiple protein source diet or CFS (casein-fish-soyabean-sugar) or a FAA-based diet. Expt 2 was designed to compare piglet response to FAA diet stored at -15 degrees with twice daily feeding, with FAA diet stored at ambient temperature (13-30 degrees) and offered ad libitum. A CFS diet was used as a positive control and the experiment was conducted over the 10-20 kg growth phase. Expt 1 used forty-eight piglets weaned at 20-22 d of age and allocated to one of six treatments formulated to contain at least 0.84 g lysine/MJ digestible energy in a randomized block design. Piglets given the CFS and Supercreep diets produced superior growth rates (518, 491 g/d) to those given a FAA diet (353 g/d) or casein diet containing 0, 10 or 20 g NaHCO3/kg respectively (365, 417, 390 g/d) between 5 and 20 kg live weight. Piglets given the casein and FAA diets had higher amino acid digestibilities than those given the Supercreep and CFS diets. The increase in the dEB of the casein diet from 64 to 183 mmol/kg improved piglet growth performance between 5 and 20 kg by 14%. All piglets given casein diets had similar ileal and faecal digestibilities, empty-body compositions, nutrient deposition rates and retention ratios. The results of Expt 2 showed that there was no beneficial effect on piglet performance of storing the FAA diet at -15 degrees and feeding twice daily. Based on the results of these two experiments, neither the casein (0, 10, 20 g NaHCO3/kg) nor FAA diets were suitable for estimating amino acid utilization by the piglet. There remain unidentified factors which limit the growth performance of piglets given the casein and FAA diets.

Amino Acids↗

PubMed2006

Effects of dietary supplementation with clostridium butyricum on the growth performance and humoral immune response in Miichthys miiuy.

The effects of dietary supplementation with Clostridium butyricum on growth performance and humoral immune response in Miichthys miiuy were evaluated. One hundred and fifty Miichthys miiuy weighing approximately 200-260 g were divided into five groups and reared in 15 tanks with closed circuiting culture system. The animals were fed 5 diets: basal diet only (control) or supplemented of the basal diet with C. butyricum at doses of 10(3) (CB1), 10(5) (CB2), 10(7) (CB3) or 10(9) (CB4) CFU/g. Compared with the control, the serum phenoloxidase activity was significantly increased by the supplementation (P<0.05), acid phosphatases activity was increased significantly (P<0.05) at the doses of 10(9) CFU/g. Serum lysozyme activity peaked at dose of 10(7) CFU/g and in the skin mucus at dose of 10(9) CFU/g. Immunoglobulin M level in the serum and skin mucus was increased except at dose of 10(3) CFU/g (P<0.05). The growth at the dose of 10(9) CFU/g was higher than that of the control (P<0.05). It is concluded that supplementation of C. butyricum can mediate the humoral immune responses and improve the growth performance in Miichthys miiuy.

Animal Feed↗

PubMed2001

Effect of dietary protein source and lysine:DE ratio on growth performance, meat quality, and body composition of growing-finishing pigs.

The effects of four protein sources (soybean meal, sunflower meal, pea, and fish meal as the main protein source) and three apparent ileally digestible Lys:DE ratios (0.50, 0.43, 0.36 and 0.42, 0.36, 0.30 g Lys/MJ DE for 30 to 60 kg BW and 60 to 105 kg BW, respectively) in pig diets on growing-finishing performance, and carcass and meat quality traits were investigated. Eight individually housed animals per treatment received the diets from 30 to 105 kg BW at a level of 3.0 times maintenance requirements of energy. The ileal digestibility of protein sources was determined in a previous digestibility experiment. Protein sources showed no differences in growth performance from 30 to 105 kg BW. From 30 to 60 kg BW soybean treatment had lowest performance. The protein sources had no effect on lean meat percentage, liver weight, or meat quality (intramuscular fat content, pH at 45 min and 24 h after slaughter, drip loss, and meat color measured 24 h and 4 d after slaughter). The experimental diets formulated on the basis of similar apparent ileal digestible lysine content resulted in similar body composition regardless of the protein source used (P > 0.05). Reducing the Lys:DE ratio from 0.50/0.43 to 0.36/0.30 (by about 28%) reduced BW gain by 119 g/d from 30 to 60 kg and by 151 g/d from 60 to 105 kg BW. The gain:feed ratio increased by 82 g/kg in the first phase and by 47 g/kg in the second phase for the highest Lys:DE treatment compared with the lowest. Reducing Lys:DE ratio did not modify meat quality traits. A high Lys:DE ratio was associated with a high lean meat percentage. Differences between the medium- and low-Lys:DE groups were not significant. Lowering the Lys:DE ratio increased (P < 0.05) crude fat and fatty tissue content and decreased (P < 0.05) protein and muscle content in the body. Ash content and bone volume were not affected by Lys:DE ratio (P > 0.05). The chemical composition of the carcass can be predicted with moderate accuracy (R2 = 0.39 to 0.58) using volumetric composition data of previously frozen carcasses. In conclusion, similar growth performance, carcass and meat quality, and body composition can be expected if diet formulation is based on the apparent ileally digestible amino acid contents of feedstuffs, independent of dietary protein sources. Diminishing Lys:DE ratios reduce growth performance but do not modify meat quality traits. The chemical composition of the carcass can be predicted with moderate accuracy using the volumetric composition of thawed carcasses.

Animal Feed↗

PubMed1990

Relationship of dietary aluminum, phosphorus, and calcium to phosphorus and calcium metabolism and growth performance of broiler chicks.

Dietary treatments providing three levels of added Al (0, .196, or .392%) as aluminum sulfate and of available phosphorus (Pav) .45, .68, or .78%) in a factorial arrangement were administered to day-old chicks in Experiment 1. Plasma inorganic phosphorus (Pi) was significantly (P less than .05) elevated by increasing Pav and was decreased by Al. Body weight gain, feed intake, and the gain:feed ratio at Day 21 were significantly decreased by increased concentrations of Al, but were unaffected by the Pav concentrations. Decreases of 39 and 73% in weight gain and of 34 and 66% in feed intake resulted from feeding .196 and .392% Al, respectively. In Experiment 2, day-old chicks were fed diets supplemented with 0 or .392% Al in combination with .9% Ca plus .45% Pav, .9% Ca plus .78% Pav, 1.8% Ca plus .45% Pav, or 1.8% Ca plus .9% Pav. After 21 days, the supplemental Al resulted in: 1) significantly poorer growth performance; 2) decreased plasma Pi, total Ca, Zn, and Mg; and 3) decreased tibia weight and breaking strength. Elevating Pav improved growth performance, plasma Pi, and tibia weight and strength, and decreased plasma total Ca. Increasing dietary Ca significantly decreased plasma Pi and increased plasma total Ca without affecting other parameters. Increasing Pav alleviated the negative effect of Al on plasma Pi without correcting the negative effect of Al on growth performance.

Aluminum↗

PubMed2002

Effect of levels of starch, fiber, and lactose on digestion and growth performance of early-weaned rabbits.

The effect of source of carbohydrate on gut histology, digestion efficiency, and growth performance in early-weaned (25 d) rabbits at the starter period (25 to 39 d) was investigated. Six diets were factorially arranged to study the effect of partial substitution of starch (0, 25, or 50%) by lactose at two levels of fiber (30 or 36% NDF). Diets were formulated to meet or exceed essential nutrient requirements of growing rabbits. A feeding trial was conducted to measure the effect of treatments on growth performance in 252 rabbits that were fed the experimental diets in the starter period and thereafter received a common feed until 60 d of age. Fecal apparent digestibility was determined at 35 d of age in nine animals per diet. The four diets with extreme lactose content were used to determine ileal apparent digestibility of starch and lactose (nine replicates per diet), weights of stomach and cecum, stomach pH, cecal fermentation traits, amylase and disaccharidase activities (10 animals per diet), and jejunal morphology (six animals per diet). Weaning increased (P < 0.001) amylase activity by 59% but decreased (P < 0.001) maltase, sucrase, and lactase activities by 30, 48, and 72%, in parallel with a reduction of villus height by 19%. Dietary NDF level did not affect either jejunal morphology or sucrase and lactase activities but increased amylase (P = 0.05) and maltase (P < 0.001) activities by 22 and 92%, respectively. Substitution of starch by lactose had no effect on jejunal morphology or enzymatic activity. Ileal lactose and starch digestibility were not affected by dietary NDF or lactose level and averaged 73.8 and 90.8%, respectively. Substitution of starch by fiber and lactose affected ileal flux of starch plus lactose (by -0.5 and +1.7 g/d) and cecal pH (by +2.1 and -2.8%, respectively). Fecal NDF digestibility was relatively low (23.1% on average) and was not affected by treatments, whereas that of lactose and starch was almost complete. An increase of dietary NDF level led to an impairment of ADG and feed efficiency in the starter (P < 0.002) and in the overall (P < 0.03) fattening period. Substitution of starch by lactose linearly decreased (P < 0.001) feed efficiency in the starter period and linearly increased (P < 0.001) diarrhea incidence in the fattening period. The results indicate that digestive capability of early-weaned rabbits is limited and should be taken into account to establish optimal levels and sources of carbohydrates in the starter diet.

Animal Feed↗

PubMed1990

Effect of naturally occurring nematode infections on growth performance of first-season grazing calves.

Liveweight of calves on 89 dairy farms was measured at the end of the grazing season and related per herd to the level of exposure to nematode infection during the grazing season. There were significant between-herd variations in antibody titres against Ostertagia spp., Cooperia spp. and Dictyocaulus viviparus as well as in pepsinogen values. All but six herds (93.1%) had gastrointestinal nematode infections, as measured by faecal egg counts in September. Faecal samples of 17 herds (19.3%) contained lungworm larvae in September. Liveweight of calves per herd deviated from -68.1 kg to +84.1 kg from the age-adjusted population mean after their first grazing season. Growth performance up to the time of liveweight measurements was significantly correlated negatively with several serological and parasitological parameters. Data could be fitted by means of both linear and segmented curvilinear regression. Antibody titre against Cooperia spp. and gastrointestinal nematode egg output measured in September accounted for 3.1% (P less than 0.10) and 6.7% (P less than 0.05), respectively, of the variation in growth performance among herds. Certain infection parameters, when combined, accounted for 9.2% of this variation; these were antibody titre against Cooperia spp. and larval counts for both gastrointestinal nematodes and lungworm. Adding certain management factors to these infection parameters resulted in a model explaining 27.6% of the observed variation in growth performance among herds. These factors were supplementary feeding, lungworm vaccination, anthelmintic treatment at housing, date of housing and herd age.

Age Factors↗

PubMed2006

Growth performance and carcass characteristics of pigs fed short-season corn hybrids.

An experiment was conducted to determine growth performance, carcass characteristics, and fat quality of growing-finishing pigs fed diets based on short-season corn hybrids. Twenty-four individually housed, Cotswold, growing pigs with an initial BW of 41.4 (SD = 1.4) kg were blocked by BW and sex and randomly allotted from within block to 1 of 3 diets to give 8 replicate pigs per diet. Experimental diets consisted of a control based on barley and 2 diets based on corn as the main energy sources. A 3-phase feeding program for 20 to 50 kg (phase I), 50 to 80 kg (phase II), and 80 to 110 kg (phase III) of BW was used. Diets for each phase contained approximately 3.5 Mcal/kg of DE, with total lysine of 0.95, 0.75, and 0.64% in phase I, II, and III diets, respectively. Average daily gain, ADFI, and G:F were monitored weekly during each phase. Pigs were slaughtered after reaching a minimum BW of 100 kg to determine carcass characteristics. There were no effects of diet on ADG, ADFI, and G:F (0.45 +/- 0.02, 0.34 +/- 0.02, and 0.31 +/- 0.02 for phase I, II, and III, respectively). Carcass length, dressing percent, LM area, loin depth, backfat thickness, belly firmness, and L*, b*, and a* fat color were not different across dietary treatments. Pigs fed one corn variety had no differences in fatty acid profile with barley-fed pigs, whereas those fed the other variety of corn had a greater (P < 0.05) concentration of PUFA in their backfat. The results indicate that growth performance, carcass characteristics, and fat quality of pigs fed diets based on short-season corn hybrids and those fed the barley-based diet were not different.

Adipose Tissue↗

PubMed2003

Effects of soybean meal particle size on growth performance of nursery pigs.

We used 360 nursery pigs (35 +/- 3 d of age) in two 21-d growth assays to determine the effects of soybean meal particle size on growth performance. In both trials, there were six pigs per pen and 10 pens per treatment. Pigs were weaned on d 21 and fed the same phase I diet for 7 d after weaning, followed by a phase II diet from d 7 to 14. On d 14, all pigs were weighed and randomly allotted to one of three dietary treatments. Experimental diets contained 61.9% corn, 34.4% soybean meal, and 3.7% vitamins and minerals. In Exp. 1, 90 barrows and 90 gilts (9.2 +/- 2.3 kg BW) were fed diets containing extruded-expelled soybean meal ground to 965, 742, or 639 microm, which resulted in whole-diet particle sizes of 728, 719, and 697 microm, respectively. Reducing extruded-expelled soybean meal particle size from 965 or 742 to 639 microm in the diet did not affect (P > 0.10) ADG (541, 538, and 542 g/d), ADFI (886, 875, and 855 g/d; as-fed basis), or gain:feed ratio (0.61, 0.61, 0.64), respectively. In Exp. 2, 90 barrows and 90 gilts (9.9 +/- 2.6 kg BW) were fed diets containing solvent-extracted soybean meal ground to 1,226, 797, or 444 microm, which resulted in whole-diet particle sizes of 732, 681, and 629 microns, respectively. Like Exp. 1, reducing particle size of solvent-extracted soybean meal did not affect (P > 0.10) ADG (482, 487, and 484 g/d), ADFI (738, 742, and 736 g/d; as-fed), or gain:feed (0.65, 0.65, and 0.65). Reducing particle size of extruded-expelled soybean meal or solvent-extracted soybean meal increased the angle of repose (maximum degree at which a pile of material retains its slope), indicating that as particle size decreased, flowability characteristics decreased. However, the angle of repose of the complete diets was greater than that for the soybean meals, which indicates that decreasing the particle size of soybean meal had minimal effects on flow characteristics of the complete diet. Previous research has shown that decreasing grain particle size improves digestibility and feed efficiency, and decreased soybean meal particle size has resulted in improved amino acid digestibility. However, the results of our experiments suggest decreasing particle size of either extruded-expelled soybean meal or solvent-extracted soybean meal does not affect nursery pig growth performance.

Animal Feed↗

PubMed1995

Effects of mill type and particle size uniformity on growth performance, nutrient digestibility, and stomach morphology in finishing pigs.

The effects of particle size uniformity and mill type used to grind corn were determined in three experiments. In Exp. 1, 120 pigs (47.8 kg initial BW) were used. Treatments were 1) a 40:60 blend of coarsely rolled (in a roller mill) and finely ground (in a hammermill) corn with a large standard deviation (sgw) of particle size (sgw of 2.7), 2) hammermilled corn with an sgw of 2.3, and 3) roller-milled corn with an sgw of 2.0. Mean particle size of the corn was approximately 850 microns for all treatments. Growth performance was not affected (P > .11); but, stomach keratinization tended to be less severe (P < .08) and apparent nutrient digestibilities were greater (P < .008) when the sgw was smaller. In Exp. 2, 128 pigs (55.3 kg initial BW) were used. Treatments were corn ground in a hammermill and a roller mill to 800 and 400 microns. Pigs fed corn ground to 400 microns were more efficient (P < .004) and had greater apparent digestibilities of DM, N, and GE (P < .001) than pigs fed corn ground to 800 microns. Mill type did not affect growth performance (P > .40), but pigs fed corn ground in the roller mill had greater apparent nutrient digestibilities (P < .008). In Exp. 3, 128 pigs (67.3 kg initial BW) were used. Treatments were corn ground to 400 microns in a hammermill and a roller mill fed in meal and pelleted forms. Pigs fed pelleted diets had greater ADG (P < .003) and gain/feed (P < .03) but also had greater incidence of ulcers (P < .04). Pigs fed roller-milled corn were more efficient (P < .05) and had a lower incidence of ulcers (P < .04), but diets with hammermilled corn had lower sgw and greater apparent digestibilities of nutrients (P < .02). Our results suggest that mill type had inconsistent effects on growth performance, but more uniform particle sizes consistently gave greater nutrient digestibilities.

Animal Feed↗

PubMed2004

Growth performance and histological intestinal alterations in piglets fed dietary raw and heated pigeon pea seed meal.

Histological intestinal villus alterations were studied in piglets fed raw (PM) or heated (HPM) pigeon pea seed meal. The trypsin inhibition rate was 99.15% in PM and 54.31% HPM. The PM and HPM were added into the basal diet (crude protein; 176.3 g/kg, gross energy; 4.15 kcal/g, control) at 20% and 40% levels, respectively. The diets were formulated in order to adjust protein to 180 g/kg and gross energy to about 4.20 kcal/g. The feed intake was not different among groups. The daily body weight gain and feed efficiency tended to decrease with the increasing PM level, and they decreased significantly in the 40% PM group compared with the control group (P < 0.05). However, HPM groups showed a growth performance similar to the control. The villus height, cell area and cell mitosis tended to decrease with the increasing PM level, and they decreased significantly in the 40% PM group compared with the control group (P < 0.05). In HPM group, these villus height, cell area and cell mitosis were significantly higher than those of the 40% PM group (P < 0.05), and did not show a significant difference compared with the control. Compared with the duodenal villus surface of the control group, the PM groups had a smooth surface due to flat cells and the HPM group showed a rough surface due to protuberated cells. The current histological alterations of intestinal villi demonstrate that the villi might be atrophied in the piglets fed raw PM due to anti-nutritional factors, resulting in the decreased growth performance, and that heating PM might abolish such a harmful effect of the anti-nutritional factors on the villus function, resulting in a similar growth performance to the control. Raw PM could be incorporated under a level of 40%, but heated PM increases the incorporation rate up to the 40% level.

Animal Feed↗

PubMed1988

Pituitary porcine growth hormone (pGH) and a recombinant pGH analog stimulate pig growth performance in a similar manner.

This study was conducted to establish the extent to which different doses of pituitary porcine growth hormone (ppGH) increase pig growth performance. Pigs were treated daily for 11 wk with 0, 35 or 70 micrograms ppGH/kg BW. In addition, these effects were compared with those produced by treating pigs with 0, 35, 70 or 140 micrograms.kg BW-1.d-1 of a recombinantly derived analog of porcine growth hormone (rpGH). This analog lacks the first seven amino acids at the NH2 terminus. Growth rate was increased similarly by ppGH and rpGH (the maximal increase was 19%). Feed efficiency was improved by ppGH and rpGH (the maximal response was 25%). This improvement in feed efficiency was associated with a decrease in feed intake (17% with the largest dose of rpGH). Both ppGH and rpGH decreased adipose tissue growth and increased muscle mass. Carcass lipid was decreased by 68% in pigs treated with the largest dose of rpGH. The recombinant pGH analog appeared to be less potent than ppGH in decreasing adipose tissue growth rate. All other parameters measured, however, indicated that rpGH mimicked the biological effects of ppGH (including binding to pig liver membranes and induction of insulin-like growth factor I production). Sensory panel evaluations indicated that neither ppGH nor rpGH affected pork palatability. Larger doses of pGH (greater than 70 micrograms/kg BW) adversely affected pig mobility. This impairment in mobility appears to be due to osteochondrosis. Our findings establish that the rpGH analog is equipotent to ppGH in stimulating growth performance and that pigs can be treated without any significant adverse effects when they are treated with less than 70 micrograms of pGH.kg BW-1.d-1.

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