Effect of wearing an N95 respirator on the internal nasal valve and the association with external nasal anatomy - a cohort study.

OBJECTIVES: To determine whether: the N95 respirator affects nasal valve patency; placement on the bony vault improves patency; and external nasal anatomy affects the outcome. METHODS: A prospective study with 50 participants was conducted. Nasal patency was measured by the minimal cross-sectional area via acoustic rhinometry, and using the Nasal Obstruction Symptom Evaluation survey, before and after wearing the N95 respirator and after adjustment. RESULTS: The minimal cross-sectional area was narrowed by 27 per cent when wearing the N95 respirator (p < 0.001), and improved by 9.2 per cent after adjustment (p = 0.003). The total Nasal Obstruction Symptom Evaluation score increased from 10.2 to 25.4 after donning the N95 respirator (p < 0.001), and decreased from 25.4 to 15.6 after adjustment (p < 0.001). There was no correlation with external nasal anatomy parameters. CONCLUSION: Wearing the N95 respirator causes narrowing of the nasal valve, and adjustment onto the bony vault improves symptoms. The findings were not affected by external nasal anatomy.

Aluminum absorption and distribution: effect of parathyroid hormone.

In rats, gastrointestinal aluminum absorption and tissue distribution were altered by parathyroid hormone; the resultant tissue concentrations were similar to those observed in dialysis patients with a fatal encephalopathy. In dialysis patients, serum aluminum and endogenous parathyroid hormone concentrations are significantly correlated. These data suggest that aluminum toxicity in dialysis patients results from oral aluminum ingestion in the presence of hyperparathyroidism.

Polybrominated biphenyl (PBB) in the growing pig diet.

Twelve pigs which averaged 13.7 kg were randomly allotted from litters to a corn-soybean meal grower diet containing 0, 20, or 200 ppm of polybrominated biphenyls (PPB). During a 16-week growth trial, average daily gain (kg), average daily feed (kg) and feed/gain for pigs on diets containing 0, 20, or 200 ppm of PBB, respectively, were 0.82, 2.45, 2.99; 0.67, 1.88, 2.79; 0.45, 1.23, 2.70. Mean daily gain differences between all lots were highly significant (p < 0.01). Blood from each pig was withdrawn biweekly through the first 8 weeks of the trial and at 4 week intervals thereafter. Hemoglobin and hematocrit differed significantly only at the 6 weeks bleeding, being reduced in pigs receiving 200 ppm of PBB. Erythrocyte reduced glutathione concentration and glutathione peroxidase activity were not significantly influenced by level of dietary PBB. Serum lactic dehydrogenase activity was significantly higher in control pigs than in either PBB supplemented lots at 16 weeks. There was no significant influence of PBB upon serum glutamic oxaloacetic transaminase, serum alkaline phosphatase or serum creatine phosphokinase. Based on these enzyme assays, PBB produced no evidence of significant necrosis of liver, myocardium, or skeletal muscle. There was no consistent effect of dietary PBB upon total serum protein concentration or electrophoretic profile. Pigs on either level of PBB did not have overt clinical signs of toxicity during the 16-week test period with the exception of a dermatosis on the ventral surface of two of the pigs receiving 200 ppm of PBB. There was a marked increase in liver weight of pigs receiving either level of dietary PBB. Heart, kidney, and adrenals of pigs receiving either level of dietary PBB were heavier as a percent of body weight than that of control pigs. Fat retention of PBB and urinary and fecal PBB excretion were significantly affected by dietary PBB level. Grossly, the glandular portion of the stomach appeared somewhat hyperplastic in pigs on 200 ppm of PBB. Two pigs which had received 200 ppm of PBB were placed on the control diet and over the next 14 weeks normal growth rate occurred. One of these pigs was killed and organ weights were normal. The other pig, a gilt, came into estrus. She was bred and conceived. At the end of gestation, four pigs were born. Three survived and grew normally; the one death at birth examined at gross necropsy did not reveal changes in organ size or other tissue alterations.

New guidelines for endoscopic localization of the anterior ethmoidal artery: a cadaveric study.

OBJECTIVES: To determine objective data to improve the methods of identification of the anterior ethmoidal artery during endoscopic dissection. STUDY DESIGN: Cadaveric dissection of adult human heads. METHODS: A 0 degrees, 4-mm rigid endoscope was used to guide uncinectomy and frontoethmoidectomy. The location of the anterior ethmoidal artery was first determined visually and then confirmed by passing a needle through the anterior ethmoidal foramen from the orbit into the nose in all cases. The distances were endoscopically measured using a simple ruler between two nasal landmarks and the anterior ethmoidal artery. RESULTS: Fifty-six nasal fossae in 28 cadavers were dissected endoscopically. The median distance between the artery and the "axilla" formed by the anterior attachment of the middle turbinate to the lateral nasal wall was 20 mm (range, 17-25 mm), irrespective of the side. The measurement differed by less than 2 mm between the sides in the same individual. The median distance between the artery and the "axilla" formed by the medial and lateral crura of the lower lateral cartilage (superomedial edge of the nostril) was 62 mm (range, 55-75 mm) for both sides. The artery was found to be in direct alignment with the two "axillae" formed by the middle turbinate and the nostril edge. CONCLUSIONS: The distance between the ethmoidal artery and the axilla of the middle turbinate showed the least intraindividual and interindividual variations. The tip of the endoscope (or the ruler) points directly at the anterior ethmoidal artery in the fovea ethmoidalis when its edge is aligned with the two nasal landmarks. These simple guidelines can aid the identification of the artery in endoscopic frontoethmoidectomy.

Foley catheter action in the nasopharynx: a cadaveric study.

OBJECTIVES: To determine the action of the Foley catheter in the posterior nasal cavity in relation to balloon volume, and to deduce its implications in the treatment of posterior epistaxis. DESIGN: Human cadaveric study. MATERIALS: Twenty nasal fossae of 10 adult cadavers. INTERVENTIONS: A Foley catheter (size 14) was inserted into the nasopharynx via each nostril. The catheter balloon was inflated to its recommended maximum volume with 15 mL of water. Firm traction was applied to the catheter. Colored liquid was instilled into the ipsilateral aspect of the nasal cavity, and liquid leakage into the contralateral side was monitored using a nasoendoscope. The balloon was reduced in volume by 1-mL steps, and the same fluid infusion and documentation procedures were performed for each reduced volume until the balloon slipped out of the nose. The procedure was repeated in the opposite nostril. MAIN OUTCOME MEASURES: Successful choanal sealing and anterior balloon shift into the nasal fossa in relation to the balloon size. RESULTS: The Foley catheter balloon sealed the choana without any leakage of infused liquid into the contralateral side at appropriate inflation volumes in 17 (85%) of 20 nasal fossae. Complete sealing between volumes of 12 and 15 mL was achieved in 13 fossae (65%), between 11 and 15 mL in 10 nasal fossae (50%), and between 5 and 15 mL in 3 nasal fossae (15%). Failure to seal at any volume occurred in 3 nasal fossae (15%). Bimodal seal (ie, complete seal at high [15 mL] and low volumes [4-7 mL], but leakage in intermediate volumes) occurred in 3 nasal fossae (15%). The balloon remained in the nasopharynx under traction and did not slip past the choanal rim to encroach on the middle and inferior turbinates until the balloon volume was reduced to between 4 and 7 mL. The balloon slid out of the nose at a volume of 5 mL or less. The inflation volumes ranging from 8 to 12 mL were statistically more effective in sealing the choana than lower volumes (4-7 mL) (P<.002, chi(2) test). CONCLUSIONS: At different inflation volumes, the Foley catheter balloon acts primarily (1) as a platform for an anterior gauze pack (at 4-15 mL); (2) as an effective seal of the choana (at 8-15 mL usually and at 4-7 mL occasionally); and (3) as a compressor of the region behind the middle and inferior turbinates (at 4-7 mL), provided that the balloon under traction does not slip out of the nose.

Polyotia--a rare external ear anomaly.

A rare case of polyotia in a 7-year old boy associated with first arch syndrome is reported. The accessory auricle formed a well defined helix and conchal bowl located anterior to a normal auricle and an atretic external auditory meatus. Surgical resection and reconstruction resulted in a good cosmetic outcome.

Effect of parenteral iron on serum electrolytes of the baby pig.

Twenty-eight 4-d-old nursing pigs were used in two trials to evaluate the effects of im injection of iron (Fe) from Fe-dextran upon subsequent serum mineral concentrations. An im injection of 150 mg of Fe from Fe-dextran was given to all pigs (n = 17) in trial 1. Serum Fe concentration increased rapidly from an initial mean of 65 to 3,466 micrograms/dl at 6 h postinjection (PI), 5,712 micrograms/dl at 24 h PI, then fell to 317 micrograms/dl at 4 d PI, 143 micrograms/dl at 7 d PI and remained about 100 micrograms/dl at 14, 21 and 28 d PI. Concentrations of other serum minerals did not appear to be influenced by the Fe-dextran injection. Treatments of Pigs (n = 11) in trial 2 were no injection, injection of dextran only, injection of 100 mg Fe from Fe-dextran and injection of 200 mg Fe from Fe-dextran. Serum Fe concentration increased rapidly after Fe-dextran injection, rising to a peak of 11,028 micrograms/dl at 6 h PI from the 100-mg Fe injection and 17,012 micrograms/dl at 6 h PI from the 200-mg Fe injection. Serum Fe concentration dropped steadily in pigs that were given no injection or injected with dextran only. Seven days after trial 2 started, all pigs that had received no injection or dextran only were injected with 100 mg Fe from Fe-dextran.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of dietary zinc levels on mineral concentration in milk.

Effects of supplemental dietary Zn levels of 0, 50, 500 and 5,000 ppm on the mineral concentration in milk of first- and second-parity sows were evaluated. Colostrum from sows fed 5,000 ppm of supplemental Zn contained less Cu and P than colostrum from sows on the other treatments. Calcium was reduced in the colostrum from sows fed 0 or 5,000 ppm Zn. Copper was reduced and Zn increased in milk from sows fed the highest Zn level compared with the other treatments during wk 1, 2 and 3 of lactation. Iron was lower in the 2nd wk milk from sows supplemented with 50 ppm Zn compared with sows on the other treatments. Copper and Zn concentrations were reduced in the 1st, 2nd and 3rd wk milk from sows fed 0, 50 or 500 ppm additional Zn compared with colostrum, but only Zn was reduced in milk from sows supplemented with 5,000 ppm Zn compared with colostrum. Calcium concentrations were increased in milk for all treatments compared with colostrum, and Mg was increased in 1st, 2nd and 3rd wk milk from sows fed 0, 50 or 500 ppm Zn and in 2nd and 3rd wk milk from sows fed 5,000 ppm Zn compared with colostrum. Phosphorus was higher in 2nd wk milk from sows fed 0 or 500 ppm Zn and higher in 3rd wk milk for sows fed 0, 500 or 5,000 ppm Zn compared with colostrum. The Fe concentration in 1st wk milk from the second-parity sows was increased compared with that from the first-parity sows for all treatments. Magnesium was reduced in second-parity colostrum compared with first parity for all treatments except the unsupplemented group.

Lysine availability in flash-dried blood meals for swine.

The available lysine content of three flash-dried blood meals was determined by use of a pig growth assay. Pigs that were 5 to 6 wk old were fed either one of the reference diets or one of the test diets for the 4-wk period of each assay. The reference diets were a corn-soybean meal basal (B) that was deficient in lysine, B+.1% L-lysine and B+.2% L-lysine. The test diets were B plus 1.5% and 3.0% of blood meal. The available lysine levels (percentage as fed) of ring-dried cattle blood meal, ring-dried swine blood meal and drum-dried cattle blood meal were determined to be 6.9, 7.4 and 6.7, respectively. All three flash-dried blood meals appeared to have similar available lysine levels and a value of 7% lysine may be used to formulate diets containing flash-dried blood meals. Incorporation of 3 or 6% drum-dried blood meal into starter diets improved N retention over a corn-soybean meal diet and did not reduce N-corrected metabolizable energy density of the diet.

Development of an assay to determine the bioavailability of potassium in feedstuffs for the young pig.

A series of four trials was conducted to verify the published requirement of .26% total K in the diet and to identify response variables useful in an assay of the bioavailability of K in feedstuffs for the young pig. Purified diets were supplemented with K at four levels as KC2H3O2 in three trials and as KHCO3 in the fourth trial. In the first three trials, the requirement was estimated by least-squares analysis of a linear-plateau response of average daily gain. Additional measures in each trial were taken for linear response to dietary K levels. The three estimates of K requirement obtained were .30, .33 and .26% total K in the diet. These three estimates were not found to be inconsistent with the published value of .26% total K in the diet. Various urinary and hematological measures also were examined during the four trials for linear response to dietary K levels. Plasma K was the only hematological response to show a significant linear relationship to dietary K levels. Urinary K concentrations and daily excretion showed a highly significant linear response to dietary K levels. Based on these results, a K bioavailability assay using urinary K measures as the primary response variable and plasma K as the secondary response variable seems the most promising.

Nitrogen balance and ileal amino acid digestibility in growing pigs fed diets reduced in protein concentration.

Two studies were conducted to assess the effect of dietary protein reduction on N utilization, N excretion, and AA digestibility in growing pigs. The objective was to determine whether pigs fed diets with a reduced CP concentration could maintain the same N retention as pigs fed an adequate diet. The second objective was to test whether reducing dietary CP concentration decreases AA digestibility. In each study, six barrows were allotted to one of six dietary treatments in a Latin square design. Treatments consisted of four corn-soybean meal-based diets containing 15, 12, 9, and 6% CP, a casein-based diet containing 15% CP, and a protein-free diet. Crystalline AA were included in the 12, 9, and 6% CP diets. The indispensable:dispensable AA ratio was maintained at 45:55 with the addition of L-glutamic acid to the 9 and 6% CP diets. The casein-based and protein-free diets were used to determine endogenous total tract N and ileal AA losses. In the first study, total N losses and N absorbed decreased linearly (P < 0.001) as dietary CP concentration decreased from 15 to 6%. Both a linear (P < 0.001) and a quadratic (P < 0.05) decrease in N retention were found with decreasing dietary CP concentration. Nitrogen retained as a percentage of intake and absorbed increased (P < 0.001) as dietary CP concentration was reduced from 15 to 6%. In the second study, six barrows were surgically fitted with a T-cannula at the terminal ileum to determine ileal AA digestibility. For all dispensable and most indispensable AA, apparent and standardized ileal digestibility increased linearly (P 0.01, and for arginine, P < 0.05) as dietary CP concentration decreased. These results indicate that dietary CP concentration can be decreased from 15 to 12% with crystalline AA supplementation to meet an ideal AA profile without adversely affecting N retention, and that decreasing dietary CP concentration from 15 to 6% increases both dispensable and indispensable AA ileal digestibility.

Bioavailability of iron from ferric choline citrate and a ferric copper cobalt choline citrate complex for young pigs.

Two experiments were conducted to determine the bioavailability for young pigs of Fe from ferric choline citrate or from a commercial mixture of Fe, Cu and Co choline citrate salts. Relative biological value of Fe from either source with a standard of 100 for FeSO4 x 7H20 was about 140 by both hemoglobin regeneration and Fe retention methods.

Iron requirements of baby pigs reared in germ-free or conventional environments on a condensed milk diet.

Baby pigs were maintained in either a germ-free or a conventional environment and fed a sterile condensed milk diet (10 micrograms Fe/g milk solids) supplemented with 0, 50 or 100 micrograms Fe/g solids from FeSO4.7H2O or given an im injection of 100 mg Fe from Fe dextran. Pigs were reared on these diets for 4 wk, and weekly measures of gain, food consumption and hematology were taken. The pigs were then killed, and organ weights were taken and tissues analyzed for Fe concentration. All conventional pigs not given supplemental Fe died. None of the unsupplemented pigs raised in the germ-free environmental died. Conventional pigs gained faster and more efficiently and became anemic more rapidly. However, conventional and germ-free pigs were similar in the efficiency with which they incorporated supplemental Fe into hemoglobin or stored Fe in liver and spleen. We concluded from this study that both germ-free and conventional pigs fed a condensed milk diet require 50 to 100 micrograms Fe/g milk solids or more than 100 mg of Fe from Fe dextran once parenterally to maintain desirable hematological traits for 4 wk.

Calcium level affects the efficacy of supplemental microbial phytase in corn-soybean meal diets of weanling pigs.

A 2 x 2 x 2 factorial experiment was conducted with 64 pigs (4 wk old, 8.04 +/- .50 kg BW) to determine the effect of various dietary concentrations of Ca, vitamin D, and microbial phytase (Aspergillus niger) on phytate-P utilization. A low-P, corn-soybean meal diet was supplemented with two levels of phytase (unit/gram), 750 (suboptimal) and 1,200 (optimal); of vitamin D (international unit/kilogram), 660 (normal) and 6,660 (high); and of Ca (percentage), .4 (low) and .8 (normal). Pen feed consumption and individual pig weights, plasma inorganic P and Ca concentrations, and plasma alkaline phosphatase (AP) activity were measured at d 10, 20, and 30. The normal dietary Ca concentration had an adverse effect (P < .05) on all the response measures. The depressive effect of the normal dietary Ca on performance was greater (P < .05) at the normal vitamin D level or at the optimal phytase level than at the other levels of these two factors. The elevation in plasma AP activity in pigs fed the normal dietary Ca was greater (P < .05) at the suboptimal than at the optimal phytase level. The decreases in plasma inorganic P concentration and increases in plasma Ca concentration associated with the normal dietary Ca were substantial. In conclusion, the normal level of Ca in the diet greatly reduced the efficacy of supplemental phytase. Raising vitamin D in the diet partially offset this adverse effect but did not produce further improvement when the Ca level was low.

Physiological relationships between microbiological status and dietary copper levels in the pig.

Ten germ-free pigs and 10 conventionally reared pigs were fed one of two nutritionally balanced diets containing either 16 ppm Cu (basal) or 283 ppm Cu (high-Cu) to evaluate the physiological relationships between Cu and microbiological environment. Germ-free pigs tended to have higher ADG and average daily feed intake (ADFI) than conventionally reared pigs. Feeding the high-Cu diet tended to reduce ADG and ADFI in germ-free pigs but it increased ADG and ADFI in conventionally reared pigs. Hemoglobin and hematocrit were higher in germ-free pigs than in conventionally reared pigs (P less than .001), and hematocrit (P less than .01) and erythrocyte count (P less than .06) were reduced by feeding the high-Cu diet. Germ-free pigs had lower total leukocyte count (P less than .01) and the relative percentages of differentiated leukocytes were altered compared with conventionally reared pigs. Feeding the high-Cu diet increased the percentage of band neutrophils and monocytes in germ-free pigs but reduced the percentage of these cells in conventionally reared pigs (P less than .04). Germ-free pigs had higher concentrations of Cu and Zn in liver and plasma (P less than .001) and greater plasma ceruloplasmin oxidase activity (P less than .001) than conventionally reared pigs did. The high-Cu diet increased liver Cu and Zn (P less than .001) and plasma Cu (P less than .001) and reduced liver and plasma Fe (P less than .05). Organ weights (g/kg BW) differed between germ-free and conventionally reared pigs, and feeding the high-Cu diet reduced thymus weights (P less than .002). Intestinal weight and thickness were reduced in germ-free pigs, and feeding the high-Cu diet generally reduced villus height and width and crypt depth in germ-free pigs, whereas it increased these measurements in conventionally reared pigs.

Effects of zeolite a or clinoptilolite in diets of growing swine.

Growth, nutrient balance, plasma ammonia levels and urinary p-cresol excretion were evaluated in growing pigs fed diets containing various levels of zeolite A or clinoptilolite. In one growth trial, crossbred pigs averaging 25 kg initial body weight were assigned to diets containing no zeolite, .3% zeolite A or .5% clinoptilolite for a 6-wk growing phase trial. Average daily gain (ADG), average daily feed intake (ADF) and feed/gain (F/G) were unaffected by supplementation of either zeolite in the diet, but metabolizable energy (ME) utilization was improved by feeding diets containing either zeolite. A second growth trial utilized the same crossbred pigs, which averaged 65 kg initial body weight, and were assigned to diets containing no zeolite, 1% zeolite A or 5% clinoptilolite for an 8-wk finishing phase trial. Average daily gain, ADF, and ME utilization were unaffected by feeding either zeolite diet, while F/G was increased in pigs fed the diet containing 5% clinoptilolite. In two nutrient balance trials, 16 crossbred pigs averaging 7.5 kg in initial body weight were fed diets containing 0, 1, 2 or 3% zeolite A in one trial and 16 crossbred pigs averaging 7.0 kg initial body weight were fed diets containing 0, 2.5, 5.0 or 7.5% clinoptilolite in a second trial. In both trials, digestible energy, ME, N-corrected ME and ME corrected for N balance and zeolite levels were linearly reduced as increasing amounts of either zeolite were fed. Daily fecal N increased and apparent digestibility of N was linearly reduced by feeding increasing amounts of zeolite A or clinoptilolite. Biological value of protein was improved linearly as higher levels of zeolite A were fed, indicating that there may be some ammonia binding to zeolite A in the gastrointestinal tract. Net protein utilization was reduced by feeding increasing levels of clinoptilolite in the diet. Calcium, P, Mg, Na, K and Fe retentions were linearly reduced by feeding increasing amounts of zeolite A in the diet, while increasing levels of clinoptilolite caused only P retention to be linearly reduced. Both free and conjugated forms of urinary p-cresol were linearly reduced by feeding increasing levels of clinoptilolite. Plasma ammonia levels were reduced at subsequent bleedings after a meal and by increasing levels of clinoptilolite.

Supplementing corn-soybean meal diets with microbial phytase linearly improves phytate phosphorus utilization by weanling pigs.

Two experiments were conducted with weanling pigs to determine the effectiveness of a dietary supplement of Aspergillus niger phytase in improving the availability of phytate-P in corn-soybean meal diets without supplemental inorganic P. Experiment 1 consisted of two P and Ca balance trials and two feeding trials. Twelve pigs (8.18 +/- .44 kg BW) were housed individually in stainless steel metabolism cages. Six pigs received 750 phytase units (PU)/g of basal diet and the other six pigs received the basal diet without supplemental phytase as control. In Exp. 2, 96 pigs (8.81 +/- .75 kg BW) were allotted to 16 partially slotted floor pens and their basal diets were supplemented with either 0, 250, 500, or 750 PU/g for 4 wk. Individual pig weights and pen feed consumption were measured weekly. Blood samples were taken from all pigs at the end of each trial in Exp. 1 and from three pigs per pen weekly in Exp. 2 to measure serum (plasma) inorganic P (P) and Ca concentrations and alkaline phosphatase (AP) activities. The results of Exp. 1 indicated that dietary phytase increased P retention by 50% (P < .0001) and decreased fecal P excretion by 42% (P < .0001). Pigs that received dietary phytase had serum P and Ca concentrations and serum AP activities that were nearly normal, whereas control pigs had values indicative of a moderate P deficiency. Favorable effects of phytase disappeared when the phytase was removed from the diet.(ABSTRACT TRUNCATED AT 250 WORDS)

Supplementing corn-soybean meal diets with microbial phytase maximizes phytate phosphorus utilization by weanling pigs.

Two experiments were conducted with crossbred weanling pigs to determine the optimal dietary supplement of Aspergillus niger phytase activity to a low-P, corn-soybean meal basal diet (BD). In Exp. 1, 50 pigs (7.61 +/- .56 kg BW) received the BD supplemented with 750, 1,050, 1,250, or 1,350 phytase units (PU)/g, or .21% P as mono-dibasic calcium phosphate (MDCaP) for 4 wk. In Exp. 2, 12 pigs (6.39 +/- .74 kg BW) were individually housed in metabolism cages and received BD, BD plus the optimal phytase activity (1,200 PU/g), or BD plus .21% P as MDCaP for 2 wk. In Exp. 1, additions of phytase > 1,050 PU/g of BD did not improve ADG, ADFI, gain/feed, or plasma AP activity. Quadratic relationships between dietary phytase activity and these measures were found and their stationary points were at approximately 1,200 PU/g of BD. Estimated maximum responses of these measures in pigs fed phytase were > or = 90% compared with MDCaP. Pigs fed 1,250 PU/g of BD maintained normal plasma P and Ca concentrations. In Exp. 2, pigs that received 1,200 PU/g of BD utilized dietary P more effectively (P < .05) than pigs fed the BD or the BD plus MDCaP. Although they consumed 44% less P per day, these pigs retained only 7% less P than pigs that received MDCaP. One thousand units of phytase activity supported retention of 1.1 mg of P from the BD, and this level of phytase supplementation was equivalent in effect to .91 mg of P from MDCaP.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of dietary copper on intestinal mucosa enzyme activity, morphology, and turnover rates in weanling pigs.

Twenty-four pigs from four litters weaned at 21 d of age (6.6 kg of BW) were used to evaluate the influence of 250 ppm of dietary Cu on intestinal mucosa glucose-6-phosphatase (GP), alkaline phosphatase (AP), and adenosine triphosphatase (ATPase) activity; mucosal morphology; and the turnover rate of the intestinal mucosa throughout the gastrointestinal tract. Pigs were allotted into four pens of six pigs each based on sex, litter, and weight. Pens were then assigned to one of two treatments: 1) corn-soybean meal-whey diet with no antimicrobials (CO), or 2) CO + 250 ppm of Cu. Pigs were fed twice daily an amount approximately equal to ad libitum intake for 14 d. On d 14, pigs were injected i.p. with [3H]thymidine (50 microCi/kg of BW) 10 h after the morning meal. One pig from each pen was euthanatized at 1, 6, 12, 20, 32, and 44 h postinjection, and intestinal tissue was collected from the duodenum, two jejunum sites (upper and lower), ileum, cecum, and colon. The activity of GP and AP in the lower jejunum tended to decrease in pigs fed Cu (P less than .11, P less than .08, respectively). The ATPase activity was not affected by treatment (P greater than .10). Crypt death, villus height, or epithelial cell size (P greater than .10) were not affected by feeding Cu. Migration rate of epithelial cells up the villus was also not affected by treatment (P greater than .10).(ABSTRACT TRUNCATED AT 250 WORDS)

Supplemental phytases of microbial and cereal sources improve dietary phytate phosphorus utilization by pigs from weaning through finishing.

This experiment was conducted to measure the nutritional and metabolic responses of pigs fed diets with continuous supplementation of microbial and cereal phytase from weaning to finishing, and to determine the feasibility of complete replacement of inorganic P addition by supplemental phytase in swine diets. Forty-eight Landrace x Hampshire x Meishan pigs were divided into four groups. In phase 1 (10 to 50 kg BW), pigs in Groups 1, 2, 3, and 4 were fed a low-P, corn-soybean meal basal diet (BD), the BD plus microbial phytase (A. ficuum) at 1,200 units/kg, the BD plus 10% wheat bran (230 units of cereal phytase/kg), and the BD + .24% inorganic P (calcium phosphate), respectively. In phase 2 (51 to 90 kg BW), these pigs were fed a similar BD or the BD plus 1,000 microbial phytase units/kg, 20% wheat bran, or .20% inorganic P, respectively. Repeated measures included growth performance, P, Ca, and N balance, metatarsal and metacarpal bone strength, serum concentration of inorganic P, Ca, and 1,25-dihydroxycholecalciferol, and serum alkaline phosphatase activity. Pigs fed the BD supplemented with microbial phytase and pigs fed the BD supplemented with inorganic P showed almost identical responses for all variables. Pigs fed the BD supplemented with cereal phytase also had responses for various measures that were similar to those of pigs fed microbial phytase or inorganic P, except for some differences in serum inorganic P concentrations and bone strength in phase 1. Because of improvements in apparent digestibility of dietary P and N, fecal excretion of these two nutrients was reduced by 31 to 62% (P < .05) in pigs fed the BD supplemented with phytase compared with pigs fed inorganic P. It is physiologically feasible and environmentally advantageous to replace inorganic P with microbial or cereal phytase in corn-soybean meal diets for this type of pig through the entire growing-finishing period.