Birth weight threshold for identifying piglets at risk for preweaning mortality.

Several studies have suggested there is a critical relationship between piglet birth weight and preweaning mortality. Thus, the objective of the current work was to identify a birth weight threshold value for preweaning mortality. Birth weight and survival data from two studies involving a combined total of 4,068 piglets from 394 litters on four commercial farms (three European, one U.

The effects of maternal dietary supplementation of cholecalciferol (vitamin D) and 25(OH)D on sow and progeny performance.

A total of 69 sows (DNA Line 200 × 400) and their progeny were used to determine if feeding a combination of vitamin D and 25(OH)D influences neonatal and sow vitamin D status, muscle fiber morphometrics at birth and weaning, and subsequent growth performance. Within 3 d of breeding, sows were allotted to one of three dietary treatments fortified with 1,500 IU/kg vitamin D (CON), 500 IU/kg vitamin D + 25 μg/kg 25(OH)D (DL), or 1,500 IU/kg vitamin D + 50 μg/kg 25(OH)D (DH). When pigs were sacrificed at birth, there were no treatment effects for all fiber morphometric measures ( > 0.

Effects of In-Feed Copper, Chlortetracycline, and Tylosin on the Prevalence of Transferable Copper Resistance Gene, tcrB, Among Fecal Enterococci of Weaned Piglets.

Heavy metals, such as copper, are increasingly supplemented in swine diets as an alternative to antibiotics to promote growth. Enterococci, a common gut commensal, acquire plasmid-borne, transferable copper resistance (tcrB) gene-mediated resistance to copper. The plasmid also carried resistance genes to tetracyclines and macrolides.

Effects of chlortetracycline and copper supplementation on the prevalence, distribution, and quantity of antimicrobial resistance genes in the fecal metagenome of weaned pigs.

Use of in-feed antibiotics such as chlortetracycline (CTC) in food animals is fiercely debated as a cause of antimicrobial resistance in human pathogens; as a result, alternatives to antibiotics such as heavy metals have been proposed. We used a total community DNA approach to experimentally investigate the effects of CTC and copper supplementation on the presence and quantity of antimicrobial resistance elements in the gut microbial ecology of pigs. Total community DNA was extracted from 569 fecal samples collected weekly over a 6-week period from groups of 5 pigs housed in 32 pens that were randomized to receive either control, CTC, copper, or copper plus CTC regimens.

Nasal carriage of mecA-positive methicillin-resistant Staphylococcus aureus in pigs exhibits dose-response to zinc supplementation.

Zinc (Zn) is often supplemented at elevated concentrations in swine diets, particularly in piglets, to prevent enteric infections and promote growth. Previous studies from Denmark have suggested a genetic linkage and a phenotypic association between Zn resistance, encoded by czrC, and methicillin-resistance conferred by mecA in Staphylococcus aureus. Such an association has not been reported in the U.

Use of serum biomarkers to predict the development and severity of osteochondrosis lesions in the distal portion of the femur in pigs.

Objective: To evaluate the use of serum biomarkers of cartilage and bone metabolism to predict the occurrence and severity of osteochondrosis (OC) lesions in the distal portion of the femur in growing swine.

Animals: 71 gilts.

Procedures: At an abattoir, serum samples for analysis of 10 biomarkers indicative of cartilage and bone metabolism were obtained prior to processing of the pigs.

Occurrence of tcrB, a transferable copper resistance gene, in fecal enterococci of swine.

High concentration of copper, fed as copper sulfate, is often used to increase growth rates in swine. Bacteria exposed to copper may acquire resistance, and in Enterococcus faecium and Enterococcus faecalis, a plasmid-borne transferable copper resistance (tcrB) gene that confers copper resistance has been reported. Our objectives were to determine the occurrence of tcrB in fecal enterococci from weaned piglets fed diets with a normal supplemental level (16.

Effect of dietary nutrients on osteochondrosis lesions and cartilage properties in pigs.

Objective: To evaluate dietary ingredients involved in cartilage and bone metabolism and their influence on osteochondrosis lesions in swine.

Animals: 80 crossbred gilts (mean initial weight, 39 kg).

Procedures: Pigs (10 pigs/treatment) were fed a corn-soybean meal basal (control) diet or the basal diet supplemented with additional minerals (copper and manganese or silicon), amino acids (proline and glycine; a combination of leucine, isoleucine, and valine; or methionine and threonine), or fatty acids (provided by fish oil) for 84 days.

Effects of administration of antimicrobials in feed on growth rate and feed efficiency of pigs in multisite production systems.

Objective: To evaluate effect of various regimens for administration of antimicrobials in feed on growth rate and feed efficiency (feed/gain) of pigs in multisite production systems.

Design: Controlled trial.

Animals: 24,099 growing pigs in 3 multisite production systems.