Application of broken-line analysis to assess floor space requirements of nursery and grower-finisher pigs expressed on an allometric basis.

Few issues in swine production are as complex as floor space allowances. One method for pork producers to calculate floor space allowance (A) is to convert BW into a 2-dimensional concept yielding an expression of A = k * BW(0.667). Data on ADG, ADFI, and G:F were obtained from published peer-reviewed studies. Five data sets were created: A = grower-finisher pigs, fully slatted floors, and consistent group size; B = grower-finisher pigs and fully slatted floors (group size did not need to be consistent); C = grower-finisher pigs, partially slatted floors, and consistent group size; D = grower-finisher pigs, partially slatted floors (group size did not need to be consistent); and E = nursery pigs, fully slatted or woven wire floors (group size did not need to be consistent). Each data set was analyzed using a broken-line analysis and a linear regression. For the broken-line analyses, the critical k value, below which a decrease in ADG occurred, varied from 0.0317 to 0.0348. In all cases the effect of space allowance on ADG was significant (P < 0.05). Using the linear analyses based on data with k values of < 0.030, the critical k values for the 4 grower-finisher data sets did not differ from those obtained using the broken-line analysis (0.0358 vs. 0.0336, respectively; P > 0.10); however, none of the linear regressions explained a significant proportion of the variation in ADG. The slopes for the nonplateau portion of the broken-line analyses based on percent values varied among data sets. For every 0.001 decrease in k (approximately 3% of the critical k value), ADG decreased by 0.56 to 1.41%, with an average value of 0.98% for the 5%-based analyses. The use of an allometric approach to express space allowance and broken-line analysis to establish space requirements seem to be useful tools for pig production. The critical k value at which crowding becomes detrimental to the growth of the pig is similar in full- and partial-slat systems and in nursery and grower-finisher stages. The critical point for crowding determined in these analyses approximated current recommendations to ensure the welfare of pigs.

One hundred three consecutive patients with anorectal malformations and their associated anomalies.

OBJECTIVE: A long-term retrospective analysis of 103 infants with anorectal malformations (ARMs) was conducted to describe any associated congenital anomalies and surgical classifications. DESIGN: Retrospective medical record review. SETTING: This case series was conducted on all infants with ARMs born at, or referred to, any of 3 major medical centers in Wichita, Kan, for close to a 22-year period. PATIENTS: The 103 infants in this study represent a consecutive sample of patients with ARMs. Patients were separated into 2 groups: isolated ARMs without associated anomalies (n = 30), and ARMs with associated anomalies (n = 73). The male-female ratio was 2:1. MAIN OUTCOME MEASURES: Patients with associated anomalies were further classified into groups of ARMs with minor anomalies; major anomalies; chromosomal abnormalities; and malformation syndromes, associations, or sequences. Only anomalies that occurred more than once were reported. Malformations were also classified according to major organ systems. RESULTS: The incidence of ARMs in our study was approximately 1 in 2500 live births. Additional anomalies were found in 71% of infants with ARMs. Associated anomalies by major organ system included genitourinary anomalies (49%), musculoskeletal anomalies (43%), craniofacial anomalies (34%), cardiovascular anomalies (27%), gastrointestinal anomalies (18%), respiratory anomalies (13%), and central nervous system anomalies (12%). The most common chromosomal abnormalities were trisomies (8%), and ARMs were associated with VATER complex (vertebral defects, anal atresia, tracheoesophageal fistula with esophageal atresia, and radial and renal anomalies) in 11 cases (11%) and VACTERL (vertebral, anal, cardiac, tracheal, esophageal, renal, and limb anomalies) in 4 cases (4%). CONCLUSIONS: Patients with ARMs have a high incidence of associated congenital anomalies. Evaluation of the most commonly affected organ systems in these infants is essential because it is these associated anomalies that account for most of the morbidity and mortality that is associated with this condition.

Effect of vaccine-induced immune activation on the performance of early-weaned pigs.

Two groups of 96 pigs were studied to determine the influence of weaning age, nursery site and a challenge to their immune system on their performance. The weaning ages were 11 to 16 days and 16 to 21 days. One nursery was on-site and the second nursery was off-site. Immune activation was stimulated by the administration of infectious bovine rhinotracheitis virus (IBR) vaccine to half of the pigs at each site. Serum virus neutralisation titres to IBR and total immunoglobulins were monitored in some of the pigs in each group. Performance was measured in terms of feed intake, average daily gain in weight, and feed conversion ratio (FCR). The mean serum immunoglobulin concentrations of all the groups of pigs tended to decrease in the first two weeks after weaning and then increase. Twelve of 20 pigs vaccinated with IBR had neutralisation titres to the virus. The site of the nursery did not significantly affect average daily gain in weight, feed intake or FCR. Pigs weaned at 16 to 21 days of age had a significantly better daily gain in weight than the pigs weaned at 11 to 16 days of age. Immune stimulation of the older weaned pigs did not influence their performance, but it had a significantly (P < 0.016) negative effect on the performance of the younger weaned pigs.