Withdrawal of antibiotic growth promoters from broiler diets: performance indexes and economic impact.

This study aimed to estimate the productive and economic impacts caused by the withdrawal of antibiotic growth promoters (AGP) from broilers diet. Indexed publications that compared diets with or without AGP (AGP+/AGP-) for broilers (from initial to final phase) were collected and the results of feed intake, weight gain, and feed conversion were compiled in a database. A meta-analysis was performed following sequential analyses: graphical approach (to observe biological data coherence), correlation (to identify related factors), and variance-covariance (to compare groups). The annual number of broiler slaughtered in Brazil, target weight gain and feed conversion for each phase, the variation in feed conversion, feed cost, and AGP costs were used to build a model to estimate the effects of the AGP withdrawal on feeding costs. The database comprised 174 scientific articles containing 183 experiments, totaling 121,643 broilers, most of which were Ross (52% of the studies). The most frequent AGP sources/forms in the database were Avilamycin (41% of the AGP+ treatments), Flavomycin (19%), Virginiamycin (16%), and Bacitracin (14%). Higher feed intake, weight gain, and lower feed conversion were attributed (P < 0.05) to AGP+ diets during Initial phase (1 to 21 D). In Final phase (22 to 42 D) no differences were observed in performance variables. Treatments AGP+ presented higher weight gain and better feed conversion in the Total period (1 to 42 D). The results of feed conversion were improved (P < 0.05) with Avilamycin and Flavomycin; Virginiamycin improved weight gain and feed conversion. In the Total period, the economic impact was $0.03 per animal and a total of $183,560,232 per year. It was concluded that broilers fed AGP+ diets have higher weight gain and better feed conversion than those fed AGP- diets, and withdrawing AGP increases production costs.

Evaluation of the overall impact of antibiotics growth promoters on broiler health and productivity during the medication and withdrawal period.

The effectiveness of some common combination of antibiotic growth promoters (AGP) on growth performance, gut health, and meat quality was evaluated during the medication and withdrawal period in broilers. A total of 540 male Arbor Acre broilers at 0 D of age were randomly assigned to 5 treatments, with 6 replicates of 18 chicks. Broilers received diets during the medication period (0 to 42 D) as follows: NC (control diet without AGP), EN (NC + enduracidin 8 ppm + colistin sulfate 8 ppm), BZ (NC + bacitracin zinc 40 ppm + colistin sulfate 8 ppm), CT (NC + chlortetracycline 50 ppm + colistin sulfate 8 ppm), and VG (NC + virginiamycin 20 ppm + colistin sulfate 8 ppm). Broilers were switched to the same finisher diet without AGP during the withdrawal period (43 to 49 D). The feed:gain ratio in EN, BZ, CT, and VG groups were significantly decreased by 0.07, 0.10, 0.06, and 0.05 during 0 to 42 D (P < 0.05), but increased by 0.19 (P > 0.05), 0.33 (P > 0.05), 0.49 (P < 0.05), and 0.69 (P < 0.05) during the withdrawal period, respectively. The jejunum villus height (VH) increased in EN group (P < 0.05) and crypt depth (CD) reduced in BZ, CT, and VG groups (P < 0.05) at 42 D, while jejunum VH increased in EN and BZ groups (P < 0.05) at 49 D compared to NC group (P < 0.05). Meat quality detection at 49 D found all AGP groups with the higher cook loss of the breast muscle, while CT group with the higher cook loss of thigh muscle. Consequently, the overall effects of 4 AGP combinations in the whole period were not significant on growth performance. Their poor growth performance during the withdrawal period should be partly attributed to the falling off a cliff of most digestive enzyme activities from 42 to 49 D. Attention should be paid to the adverse effects of AGP supplementation on meat quality, especially cook loss.

Comparison of performance and feed digestibility of the non-antibiotic feed supplement (Novacid) and an antibiotic growth promoter in broiler chickens.

Antibiotic growth promoters have been widely used in poultry to improve overall performance. The emergence of antibiotic resistance has resulted in sanctions imposed on the use of antibiotics in poultry diets, and alternatives such as herbal extracts are being considered to improve growth performance. The aim of this study was to compare the performance and feed digestibility of the feed supplement Novacid, which contains organic acids, glucomannan, and phytochemicals, with that of the antibiotic growth promoter bacitracin methylene disalicylate (BMD) in commercial broiler chickens. Six hundred 1-d-old Ross × Ross 308 male broiler chicks were randomly and equally assigned to six treatment groups with five replicates each (20 chicks per replicate). The chicks were fed a corn-soybean meal basal diet, and divided into two groups: unchallenged and challenged with E. coli (400 mg/kg Escherichia coli inoculation). Each of these groups was divided into three study groups: untreated, treated with 0.05% Novacid, and treated with 400 mg/kg BMD. At day 42, inclusion of Novacid or BMD significantly (P < 0.05) improved the performance in the unchallenged groups relative to the control group. However, in E. coli-challenged groups, Novacid and BMD did not improve performance. Ileal digestibility of crude fat, crude protein, and gross energy were reduced in the Novacid group (P < 0.05). BMD and Novacid were equally effective in controlling ileal nutrient digestibility and feed coliform count (P < 0.05). Novacid reduced cecal E. coli and Salmonella count compared to BMD and control. Thus, a phytochemical feed supplement with organic acids and glucomannan could be an effective substitute for antibiotic growth promoters in broiler diets, but cannot replace antibiotics to counter potent infectious agents such as E. coli.

Effects of feeding Original XPC™ to broilers with a live coccidiosis vaccine under industrial conditions: Part 2. Cecal microbiota analysis.

Biological supplements in poultry feed are of continued interest due to the improvements in growth performance, protection from pathogen invasion, and benefits in overall host health. The fermentation metabolites of Diamond V Original XPC™ (XPC) have previously been shown to improve commercial performance and reduce Salmonella in poultry. The current study sought to characterize the cecal microbiota using culture-independent analysis based on 16S rRNA gene in Coccivac-D sprayed broilers supplemented with XPC and/or Salinomycin (SAL). Ross 708 male broilers (n = 640) were assigned to one of 4 treatments: Cocci-vaccine (T1), Cocci-vaccine + XPC (T2), Cocci-vaccine + SAL (in the grower diet only) (T3), and Cocci-vaccine + SAL (in the grower diet only) + XPC (T4). Analysis with a PCR-based denaturing gradient gel electrophoresis (DGGE) indicated a shift in the microbial populations present at the various sampling ages - 16, 28, and 42 days. Phylogenetic analysis indicated further consistency in microbial communities directly related to bird age. Identification of microbial communities present and the assessment of their respective quantities using an Illumina MiSeq indicated treatment with XPC had no significant impact on microbial diversity (Chao1 index, observed operational taxonomic unit (OTU) and phylogenetic diversity (PD) whole tree). Sampling age revealed significantly greater diversity at 16 and 28 d (P < 0.05) as compared to the 42 d for the Shannon diversity index, while showing significantly decreased richness and diversity in the 42 d sampling age (Chao1 and observed OTU; P < 0.05). The results of the current study indicate that the chicken intestinal microbiota are impacted more by temporal changes rather than by the feed additive studied.

A comparison of slice characteristics and sensory characteristics of bacon from immunologically castrated barrows with bacon from physically castrated barrows, boars, and gilts.

The objectives were to compare slice characteristics and sensory attributes of bacon from immunologically castrated (IC) barrows with bacon from other sexes using a trained sensory panel. Bacon was obtained for sensory evaluation from 3 experiments. In Exp. 1, trimmed and squared bellies (n=180) of IC barrows, IC barrows fed ractopamine hydrochloride (IC+RAC), physically castrated (PC) barrows, intact males (IM), and gilts were used. Data were analyzed as a general linear mixed model and pen (n=48) served as the experimental unit. Treatment (sex or diet) was a fixed effect in all 3 experiments. In Exp. 2, untrimmed, natural fall bellies (n=96) from IC and PC barrows fed 0 or 30% or a withdrawal distillers dried grains with solubles (DDGS) program when slaughtered at 5 wk after the second dose (25 wk of age) were used. In Exp. 3, untrimmed, natural fall bellies (n=96) from IC and PC barrows fed the same experimental diets as in experiment 2 but slaughtered at 7 wk after the second dose (27 wk of age) were used. Data from Exp. 2 and 3 were analyzed as a 2×3 factorial arrangement in a randomized complete block design and pen was the experimental unit. Bellies from all 3 experiments were processed using the same protocols. In Exp. 1, IM had the greatest (P<0.0001) boar aroma and flavor scores among all treatments. No differences were detected among the other treatment groups for boar aroma or flavor. Intact males had the least (P<0.0001) desirable cured bacon aroma and flavor among all treatments. No differences were detected among the other treatment groups for bacon aroma or flavor. There were no differences in bacon aroma or off-flavor between IC and PC barrows slaughtered at 5 wk after the second dose regardless of DDGS feeding program. Bacon from PC barrows was saltier (P<0.01) than bacon from IC barrows when slaughtered at 5 wk after the second dose. There were no differences in bacon aroma, off-aroma, bacon flavor, or saltiness between IC and PC barrows slaughtered at 7 wk after the second dose regardless of DDGS feeding program. Total slice area of bacon slices from IC barrows slaughtered at 5 wk after the second dose were less (P<0.01) than PC barrows, but the differences diminished (P=0.16) when slaughtered at 7 wk after the second dose. Overall, panelists successfully detected boar odor and flavor in Exp. 1. Immunological castration was as effective as physical castration at eliminating boar aroma and boar flavor in bacon even when feeding differing DDGS feeding programs or when slaughtered at 5 or 7 wk after the second dose.

An update on alternatives to antimicrobial growth promoters for broilers.

Livestock performance and feed efficiency are closely interrelated with the qualitative and quantitative microbial load of the animal gut, the morphological structure of the intestinal wall and the activity of the immune system. Antimicrobial growth promoters have made a tremendous contribution to profitability in intensive husbandry, but as a consequence of the increasing concern about the potential for antibiotic resistant strains of bacteria, the European Commission decided to ban all commonly used feed antibiotics. There are a number of non-therapeutic alternatives, including enzymes, (in)organic acids, probiotics, prebiotics, etheric oils and immunostimulants. Their efficacy and mode of action are briefly described in this review.

Effect of dietary protein and lysine fluctuations in the absence and presence of ractopamine on performance and carcass quality of late-finishing pigs.

Two experiments with finishing pigs were conducted to evaluate the effects of fluctuating dietary CP levels and ractopamine on performance and carcass traits. In Exp. 1, a total of 408 finishing pigs (mixed sex) were assigned to 1 of 4 protein regimens. Average initial and final BW were 89 and 123 kg, respectively. Pigs on treatments 1 to 4 were fed 16, 11, 16, and 13% CP from wk 0 to 2, respectively. From wk 2 to 5, the pigs on regimens 1 to 4 were then fed 15, 18.33, 18, and 20% CP, respectively, with regimens 3 and 4 also containing supplemental ractopamine (9.9 mg/kg) from wk 2 to 5. Overall (wk 0 to 5), BW gain, G:F, loin depth, percentage of lean, and dressing percentage were improved (P < 0.05) in pigs on regimens 3 and 4 compared with those on regimens 1 and 2. No statistically significant overall (wk 0 to 5) protein sequence regimen differences occurred between the standard regimens (1 and 3) and the low-high CP regimens (2 and 4). Experiment 2 involved 172 finishing pigs (mixed sex) in 2 protein regimens. Average initial and final BW were 91 and 136 kg, respectively. The diets consisted of 1) a control (16% CP from d 0 to 14, 18% CP + 4.95 mg of ractopamine/kg from d 14 to 24, and 18% CP + 9.9 mg of ractopamine/kg from d 24 to 35; 2) a low-high CP regimen (12.5% CP from d 0 to 14, 20.33% CP + 4.95 mg of ractopamine/kg from d 14 to 24, and 20.33% CP + 9.9 mg of ractopamine/kg from d 24 to 35. From d 0 to 14, pigs fed the low CP diet (12.5% CP) had reduced (P < 0.05) BW gain and G:F compared with those fed the control diet (16% CP). In contrast, from d 14 to 35, pigs on the low-high regimen had improved (P < 0.08) BW gain and G:F compared with pigs on the control regimen. Despite the wide dietary CP fluctuations for pigs in Exp. 2, performance and carcass traits were similar for both regimens over the 35-d test period. These data indicate that pigs fed deficient levels of CP and Lys for 14 d, followed by increased levels of CP and Lys during a subsequent 21-d period can recover and achieve growth performance and carcass merit equal to that achieved with a conventional protein feeding regimen.

Hyaluronan based porous nano-particles enriched with growth factors for the treatment of ulcers: a placebo-controlled study.

The present study describes the production of hyaluronan based porous microparticles by a semi-continuous gas anti-solvent (GAS) precipitation process to be used as a growth factor delivery system for in vivo treatment of ulcers. Operative process conditions, such as pressure, nozzle diameter and HYAFF11 solution concentrations, were adjusted to optimize particle production in terms of morphology and size. Scanning electron microscopy (SEM) and light scattering demonstrated that porous nano-structured particles with a size of 300 and 900 nm had a high specific surface suitable for absorption of growth factors from the aqueous environment within the polymeric matrix. Water acted as a plasticizer, enhancing growth factor absorption. Water contents within the HYAFF11 matrix were analyzed by differential scanning calorimetry (DSC). The absorption process was developed using fluorescence dyes and growth factors. Immunohistochemical analysis confirmed the high efficiency of absorption of growth factor and a mathematical model was generated to quantify and qualify the in vitro kinetics of growth factor release within the polymeric matrix. In vivo experiments were performed with the aim to optimize timed and focal release of PDGF to promote optimal tissue repair and regeneration of full-thickness wounds.

Comparison of alternative beef production systems based on forage finishing or grain-forage diets with or without growth promotants: 2. Meat quality, fatty acid composition, and overall palatability.

Five beef cattle management regimens were evaluated for their effect on meat quality, fatty acid composition, and overall palatability of the longis-simus dorsi (LD) muscle in Angus cross steers. A 98-d growing phase was conducted using grass silage with or without supplementation of growth promotants (Revalor G and Rumensin) or soybean meal. Dietary treatments in the finishing phase were developed with or without supplementation of growth promotants based on exclusive feeding of forages with no grain supplementation, or the feeding of grain:forage (70:30) diets. Growth promotants increased (P < 0.01) shear force and tended (P = 0.06) to increase toughness of the LD muscle due to limited postmortem proteolytic activity (lower myofibrillar fragmentation index value; P = 0.02). Grain feeding increased DM and intramuscular fat content (P = 0.03 and P = 0.05, respectively) in the LD but decreased the sensory panel tenderness score (P = 0.01). Growth promotants increased (P

Improving culture conditions for temporomandibular joint disc tissue engineering.

BACKGROUND: The temporomandibular joint (TMJ) is extremely important for activities like eating and talking, which can become painful and difficult for patients with TMJ dysfunction. Tissue engineering is a potential alternative to current surgical interventions through replacement of diseased or injured tissue with a functional construct. Since research with TMJ disc cells began relatively recently, optimal culturing conditions must be determined. METHODS: Metabolic additives, L-glutamine, L-alanyl-L-glutamine, sodium pyruvate, and insulin, were examined for their effects on TMJ disc cells in monolayer. Effects of L-proline were examined in three-dimensional (3-D) culture at concentrations of 0, 25 and 100 mg/l. RESULTS: The combination of L-glutamine, sodium pyruvate, and insulin improved cell proliferation rates without affecting collagen production or gene expression. No differences were observed in mechanical properties of the engineered constructs; however, collagen and glycosaminoglycan quantities normalized to cell number decreased at the highest concentration of L-proline. CONCLUSION: This work identified supplements for 2-D monolayer expansion. Other supplements or culture conditions still need to be investigated for 3-D tissue production. This work improves upon porcine TMJ disc cell culturing conditions, taking us closer to being able to engineer the TMJ disc.

Copper resistance in Enterococcus faecium, mediated by the tcrB gene, is selected by supplementation of pig feed with copper sulfate.

The tcr gene cluster mediates in vitro copper resistance in Enterococcus faecium. Here we describe the selection of tcr-mediated copper resistance in E. faecium in an animal feeding experiment with young pigs fed 175 mg copper/kg feed (ppm), which is the concentration commonly used for piglets in European pig production. tcr-mediated copper resistance was not selected for in a control group fed low levels of copper (6 ppm). We also show coselection of macrolide- and glycopeptide-resistant E. faecium in the animal group fed the high level of copper. Finally, we identify the tcr genes in the enterococcal species E. mundtii, E. casseliflavus, and E. gallinarum for the first time.

Clinical approach to wounds: débridement and wound bed preparation including the use of dressings and wound-healing adjuvants.

This is a clinical review of current techniques in wound bed preparation found to be effective in assisting the wound-healing process. The process begins with the identification of a correct diagnosis of the wound's etiology and continues with optimizing the patient's medical condition, including blood flow to the wound site. Débridement as the basis of most wound-healing strategies is then emphasized. Various débridement techniques, including surgery, topical agents, and biosurgery, are thoroughly discussed and illustrated. Wound dressings, including the use of negative pressure wound therapy, are then reviewed. To properly determine the timing of advance therapeutic intervention, the wound-healing progress needs to be monitored carefully with weekly measurements. A reduction in wound area of 10 to 15 percent per week represents normal healing and does not mandate a change in the current wound-healing strategy. However, if this level of wound area reduction is not met consistently on a weekly basis, then alternative healing interventions should be considered. There is a growing body of evidence that can provide guidance on the appropriate use of such adjuvants in the problem wound. Several adjuvants are discussed, including growth factor, bioengineered tissues, and hyperbaric medicine.

Modulation of leptin, insulin, and growth hormone in obese pony mares under chronic nutritional restriction and supplementation with ractopamine hydrochloride.

Horses fed beyond their nutritional requirement and that are physically inactive will develop obesity, which is often accompanied by insulin resistance and heightened risk of laminitis. The use of pharmacologic agents in combination with nutritional restriction may promote weight loss in obese horses unable to exercise because of laminitic pain. This study shows that reducing feed intake of brome grass hay to 75% of ad libitum intake in obese pony mares reduces body weight without induced exercise. Additional supplementation of ractopamine hydrochloride for 6 weeks resulted in a tendency for increased weight loss. Subsequent modulation of obesity-associated hormones, leptin and insulin, as a result of caloric restriction was observed.

Evaluation of the effects of dietary fat, conjugated linoleic acid, and ractopamine on growth performance, pork quality, and fatty acid profiles in genetically lean gilts.

An 8-wk study of the effects of CLA, rendered animal fats, and ractopamine, and their interactive effects on growth, fatty acid composition, and carcass quality of genetically lean pigs was conducted. Gilts (n = 228; initial BW of 59.1 kg) were assigned to a 2 x 2 x 3 factorial arrangement consisting of CLA, ractopamine, and fat treatments. The CLA treatment consisted of 1% CLA oil (CLA-60) or 1% soybean oil. Ractopamine levels were either 0 or 10 ppm. Fat treatments consisted of 0% added fat, 5% choice white grease (CWG), or 5% beef tallow (BT). The CLA and fat treatments were initiated at 59.1 kg of BW, 4 wk before the ractopamine treatments. The ractopamine treatments were imposed when the gilts reached a BW of 85.7 kg and lasted for the duration of the final 4 wk until carcass data were collected. Lipids from the belly, outer and inner layers of backfat, and LM were extracted and analyzed for fatty acid composition from 6 pigs per treatment at wk 4 and 8. Feeding CLA increased (P < 0.02) G:F during the final 4 wk. Pigs fed added fat as either CWG or BT exhibited decreased (P < 0.05) ADFI and increased (P < 0.01) G:F. Adding ractopamine to the diet increased (P < 0.01) ADG, G:F, and final BW. The predicted carcass lean percentage was increased (P < 0.05) in pigs fed CLA or ractopamine. Feeding either 5% fat or ractopamine increased (P < 0.05) carcass weight. Adding fat to the diets increased (P < 0.05) the 10th rib backfat depth but did not affect predicted percent lean. Bellies of gilts fed CLA were subjectively and objectively firmer (P < 0.01). Dietary CLA increased (P < 0.01) the concentration of saturated fatty acids and decreased (P < 0.01) the concentration of unsaturated fatty acids of the belly fat, both layers of backfat, and LM. Ractopamine decreased (P < 0.01) the i.m. fat content of the LM but had relatively little effect on the fatty acid profiles of the tissues compared with CLA. These results indicate that CLA, added fat, and ractopamine work mainly in an additive fashion to enhance pig growth and carcass quality. Furthermore, these results indicate that CLA results in more saturated fat throughout the carcass.

Are recombinant human bone morphogenetic protein-7 and tobramycin compatible? An experiment in rats.

OBJECTIVES: To evaluate the effects of local antibiotics on bone morphogenetic protein-induced new bone formation in vivo. DESIGN: In the research laboratory, inactive collagenous bone matrix was reconstituted with 1 microg of recombinant human bone morphogenetic protein-7 and implanted subcutaneously in the thorax bilaterally in 30 male Long-Evans rats. INTERVENTION: In group A (n = 2), the inactive collagenous bone matrix alone was implanted, bilaterally, and one of these pellets treated with either 500 microg tobramycin in aqueous solution or 3 tobramycin-impregnated polymethyl methacrylate beads. In group B (n = 4), the reconstituted pellets were not treated with tobramycin. In group C (n = 8), 1 reconstituted pellet in each rat was treated with 500 microg tobramycin in aqueous solution. In group D (n = 8), 3 tobramycin beads were placed in contact with 1 of the 2 reconstituted pellets in each rat. In group E (n = 8), 3 tobramycin beads were placed on the dorsal surface of 4 of the rats. All rats were killed on day 11. MAIN OUTCOME MEASUREMENT: Bone formation was evaluated by alkaline phosphatase assay and histology. Tobramycin elution from the beads after day 11 was measured by placing the explanted beads into a phosphate buffer solution to incubate for 24 hours. RESULTS: There was no difference in the alkaline phosphatase activity between the tobramycin treated and untreated implants. Histologic evaluation of the implants revealed areas of robust new bone formation in both the tobramycin treated and untreated implants. CONCLUSIONS: The results by both alkaline phosphatase assay and histologic evaluation in this rat model indicate that there is no inhibition of recombinant human bone morphogenetic protein-7-induced new bone formation by locally applied tobramycin. Recombinant human bone morphogenetic protein-7 is osteoinductive in the presence of locally applied tobramycin. A composite osteogenic device containing both tobramycin and recombinant human bone morphogenetic protein-7 may be developed that can simultaneously induce bone healing and decrease the risk for infection.

Comparison of methods for point of care preparation of autologous platelet gel.

A platelet gel (PG) is produced by the addition of calcium chloride and thrombin to a platelet concentrate (PC). PG releases multiple growth factors, which have the ability to initiate and stimulate one growth factor's function in the presence of others. This finding has resulted in the use of PG in orthopedic, plastic, and reconstructive surgery. The study compared the commercial systems available for the preparation of PG. All procedures were performed according to the manufacturers directions. The devices were evaluated with respect to ease of use, collection efficiency, platelet quality, and growth factor release. The SmartPReP requires only four processing steps compared to 12 to 24 required by other devices. The SmartPReP and the CATS were the most reproducible, as evidenced by their low coefficient of variation of 13% and 16%. The mean platelet yield was 72% for the SmartPReP, 58% for the 3iPCCS, 54% for the Sequestra, 31% for the Secquire, 31% for the CATS, 27% for the Interpore Cross, and 42.6% for the Biomet GPS. The mean total amount of PDGF-AB and TGF-B1 obtained from the SmartPReP is greater than other systems evaluated. The SmartPReP produced a consistent PC with a yield that was four times baseline range with the lowest coefficient of variation.

Characterization of a colostrum replacer and a colostrum supplement containing IgG concentrate and growth factors.

The objective of this study was to characterize absorption of colostrum replacer (CR) or supplement (CS) containing fractions of bovine plasma. Immunoglobulin concentrate (IGC) was prepared from bovine blood to a final purity of approximately 90% IgG. Blood was also processed to produce a fraction containing elevated concentrations of IGF-I and TGF-beta (GF). Both IGC and GF were spray-dried and blended with other ingredients to produce CR (30% IgG) or CS (15% IgG) containing 0 or 5% GF. Holstein bull calves were assigned to one of five treatments: 1) Pooled colostrum (MC)--1.9 L of pooled colostrum at 1 and 8 h of age to provide over 150 g of IgG; 2) Low supplement (LC)--1.9 L of CS at 1 and 8 h of age to provide 150 g of IgG; 3) Low supplement + GF (LG)--1.9 L of a CS with GF at 1 and 8 h of age to provide 150 g of IgG; 4) High supplement (HC)--1.9 L of CR at 1 h of age to provide 150 g of IgG and 1.9 L of a commercial milk replacer (MR) at 8 h of age; and 5) High supplement + GF (HG)--1.9 L of a CR with GF at 1 h of age to provide 150 g of IgG and 1.9 L of MR at 8 h of age. Apparent efficiency of IgG absorption was higher for calves fed HC and HG compared with those fed LC and LG and was lower for calves fed LG and HG compared with those fed LC and HC. IgG concentrations at 24 h were highest in calves fed MC compared with other calves and were higher in calves fed HC and HG compared to LC and LG. Calves fed LG and HG had lower IgG concentrations at 24 h of age compared with those fed LC and HC. These results indicate that 150 g of IgG provided in one dose soon after birth is superior to 150 g of IgG fed in two doses 7 h apart. Also, addition of a plasma fraction containing elevated concentrations of IGF-I and TGF-beta decreased IgG absorption in the neonatal calf.

Long-term effects of dextrose prolotherapy for anterior cruciate ligament laxity.

CONTEXT: Use of dextrose prolotherapy. Prolotherapy is defined as injection that causes growth of normal cells or tissue. OBJECTIVE: Determine the 1 and 3 year efficacy of dextrose injection prolotherapy on anterior cruciate ligament (ACL) laxity. After year 1, determine patient tolerance of a stronger dextrose concentration (25% versus 10%). DESIGN: Prospective consecutive patient trial. SETTING: Outpatient physical medicine clinic. PATIENTS OR OTHER PARTICIPANTS: Eighteen patients with 6 months or more of knee pain plus ACL knee laxity. This laxity was defined by a KT1000 anterior displacement difference (ADD) of 2 mm or more. INTERVENTION: Intraarticular injection of 6-9 cc of 10% dextrose at months 0, 2, 4, 6, and 10. Injection with 6 cc of 25% dextrose at 12 months. Then, depending on patient preference, injection of either 10% or 25% dextrose every 2-4 months (based on patient preference) through 36 months. MAIN OUTCOME MEASURES: Visual analogue scale (VAS) for pain at rest, pain on level surfaces, pain on stairs, and swelling. Goniometric flexion range of motion, and KT1000-measured ADD were also measured. All measurements were obtained at 0, 6, 12 and 36 months. RESULTS: Two patients did not reach 6 month data collection, 1 of whom was diagnosed with disseminated cancer. The second was wheelchair-bound and found long-distance travel to the clinic problematic. Sixteen subjects were available for data analysis. KT1000 ADD, measurement indicated that 6 knees measured as normal (not loose) after 6 months, 9 measured as normal after 1 year (6 injections), and 10 measured as normal at 3 years. At the 3 year follow-up, pain at rest, pain with walking, and pain with stair use had improved by 45%, 43%, and 35% respectively. Individual paired t tests indicated subjective swelling improved 63% (P = .017), flexion range of motion improved by 10.5 degrees (P = .002), and KT1000 ADD improved by 71% (P = .002). Eleven out of 16 patients preferred 10% dextrose injection. CONCLUSION: In patients with symptomatic anterior cruciate ligament laxity, intermittent dextrose injection resulted in clinically and statistically significant improvement in ACL laxity, pain, swelling, and knee range of motion.

Dietary supplementation with zinc and a growth factor extract derived from bovine cheese whey improves methotrexate-damaged rat intestine.

BACKGROUND: Oral administration of zinc or bovine whey-derived growth factor extract (WGFE) is known to reduce intestinal permeability and ameliorate methotrexate (MTX)-induced mucositis, respectively. OBJECTIVE: We examined the effects of zinc, WGFE, and zinc plus WGFE on gut damage in MTX-treated rats. DESIGN: Rats (n = 16/group) were fed zinc (1000 mg/kg diet), WGFE (32 mg/kg diet), zinc plus WGFE, or control (10 mg Zn/kg diet) diets for 7 d and then injected subcutaneously with MTX (2.5 mg/kg) for 3 d to induce gut damage. Gut histology and intestinal permeability were assessed. RESULTS: The Zn+WGFE diet was associated with both reduced gut damage on day 5 and enhanced recovery on day 7. The WGFE diet ameliorated gut damage, whereas the Zn and Zn+WGFE diets enhanced repair. Gut metallothionein and tissue zinc concentrations were significantly (P < 0.01) higher with Zn and Zn+WGFE on days 5 and 7 than without zinc supplementation. The Zn and Zn+WGFE diets significantly (P < 0.05) decreased gut permeability on days 3-4 compared with the control diet. Intestinal permeability was significantly (P < 0.05) increased on days 5-6. On days 6-7, only the WGFE diet improved gut permeability (by 80%) compared with the control diet. CONCLUSIONS: Dietary administration of WGFE and a pharmacologic dose of zinc reduced intestinal damage and enhanced recovery, respectively. WGFE also improved gut permeability after MTX-induced bowel damage. In combination, zinc and WGFE hastened repair of gut damage, which may have clinical application in chemotherapy-induced mucositis.

An update on angiogenesis therapy.

Angiogenesis is a novel approach for the therapy of various ischemia-related pathophysiologic conditions. Proangiogenic growth factors have shown promising results in preclinical studies using protein- and gene-based therapies. However, their success in clinical trials is hindered by the lack of an optimal delivery strategy that would provide sustained and localized levels of the growth factors in the diseased tissue. Targeted delivery of proangiogenic agents is expected to demonstrate therapeutic efficacy of growth factors at relatively lower doses, without the risk of systemic toxicity in terms of unwanted angiogenesis. To achieve the above objectives, various drug delivery systems are under investigation. This review describes the basic mechanism of action of growth factors, their current status in preclinical and clinical studies, and the issue of drug delivery.