Genetic associations for gilt growth, compositional, and structural soundness traits with sow longevity and lifetime reproductive performance.

The objective of this study was to estimate genetic associations for gilt growth, compositional, and structural soundness with sow longevity and lifetime reproduction. Performance and pedigree information from 1,447 commercial females from 2 genetic lines were included in the data analyzed. Growth was expressed as days to 113.5 kg BW (DAYS) and compositional traits included loin muscle area (LMA), 10th rib backfat (BF10), and last rib backfat (LRF). Structural soundness traits included body structure traits [length (BL), depth (BD), width (BWD), rib shape (BRS), top line (BTL), and hip structure (BHS)], leg structure traits [front legs: legs turned (FLT), buck knees (FBK), pastern posture (FPP), foot size (FFS), and uneven toes (FUT); rear legs: legs turned (RLT), leg posture (RLP), pastern posture (RPP), foot size (RFS), and uneven toes (RUT)], and overall leg action (OLA). Lifetime (LT) and removal parity (RP) were considered as longevity traits whereas lifetime reproductive traits included lifetime total number born (LNB), lifetime number born alive (LBA), number born alive per lifetime day (LBA/LT), and percentage productive days from total herd days (PD%). Genetic parameters were estimated with linear animal models using the average information REML algorithm. Second, to account for censored longevity and lifetime reproduction records, genetic parameters were estimated using Markov Chain Monte Carlo and Gibbs sampling methods. Similar estimates were obtained across the analysis methods. Heritability estimates for growth and compositional traits ranged from 0.50 to 0.70 and for structural soundness traits from 0.07 to 0.31. Longevity and lifetime reproductive trait heritability estimates ranged from 0.14 to 0.17 when REML was used. Unfavorable genetic correlations were obtained for DAYS with LT, RP, LNB, LBA, and PD% and for LRF with PD%. However, LMA was favorably associated with LT, RP, and LNB. Moderate to high correlations were obtained for BL and BRS with all longevity and lifetime reproductive traits. Correlations of BWD with LT and RP were moderate. Associations for leg soundness traits with longevity and lifetime reproductive traits were mainly low and nonsignificant (P ≥ 0.10). However, RLP was moderately correlated with LBA/LT and PD%. Current results indicate that selection for fewer DAYS has an antagonistic effect on lifetime performance. Furthermore, great BL, flat BRS, narrow BWD, and upright RLP seem detrimental to sow longevity and lifetime reproduction.

Genetic parameters for growth, body composition, and structural soundness traits in commercial gilts.

The objective of this study was to estimate genetic parameters for growth, body composition, and structural soundness traits in commercial gilt lines. The data included 1,449 gilts: 462 females from a grandparent maternal line and 987 from a parent maternal line. Growth was expressed as number of days to a constant 113.5 kg BW (DAYS) and compositional traits included loin muscle area (LMA), 10th rib backfat (BF10), and last rib backfat (LRF). Subjective structural soundness evaluation was completed using a 9-point scale and included: body length (BL), body depth (BD), body width (BWD), rib shape (BRS), top line (BTL), and hip structure (BHS); front legs: legs turned (FLT), buck knees (FBK), pastern posture (FPP), foot size (FFS), and uneven toes (FUT); rear legs: legs turned (RLT), leg posture (RLP), pastern posture (RPP), foot size (RFS), and uneven toes (RUT); and overall leg action (OLA). Genetic parameters were estimated with multivariate linear animal models, using the average information REML algorithm. Heritability estimates for growth and body composition traits ranged from 0.50 to 0.70, for body structure traits from 0.15 to 0.31, for leg structure traits from 0.07 to 0.31, and the estimate for OLA was 0.12. Several moderate to high genetic correlations were obtained among body structure traits, whereas correlations among leg structure traits were mainly low and nonsignificant. A strong correlation was found between FPP and OLA (P < 0.001); more upright FPP coincided with inferior OLA. Furthermore, FBK and FFS appeared to be favorably associated with OLA (0.05 < P < 0.10). Body structure trait correlations among each other and with leg soundness traits were primarily favorable. Correlations indicated that great BL and high BTL coincided with each other and deterioration of other structural soundness traits. Although genetic correlations obtained for DAYS and backfat measurements with structural soundness traits had an unfavorable trend, they were mainly low to moderate (i.e., simultaneous genetic improvement would be possible, including adversely associated traits). Due to greater heritabilities, faster genetic change could be expected for compositional and body structure traits than leg structure traits. Because of the genetic relationship among the trait groups, using information across traits when making selection decisions could result in genetic improvement among leg soundness traits.

Whole-genome association analyses for lifetime reproductive traits in the pig.

Profits for commercial pork producers vary in part because of sow productivity or sow productive life (SPL) and replacement costs. During the last decade, culling rates of sows have increased to more than 50% in the United States. Both SPL and culling rates are influenced by genetic and nongenetic factors. A whole-genome association study was conducted for pig lifetime reproductive traits, including lifetime total number born (LTNB), lifetime number born alive (LNBA), removal parity, and the ratio between lifetime nonproductive days and herd life. The proportion of phenotypic variance explained by markers was 0.15 for LTNB and LNBA, 0.12 for removal parity, and 0.06 for the ratio between lifetime nonproductive days and herd life. Several informative QTL regions (e.g., 14 QTL regions for LTNB) and genes within the regions (e.g., SLC22A18 on SSC2 for LTNB) were associated with lifetime reproductive traits in this study. Genes associated with LTNB and LNBA were similar, reflecting the high genetic correlation (0.99 ± 0.003) between these traits. Functional annotation revealed that many genes at the associated regions are expressed in reproductive tissues. For instance, the SLC22A18 gene on SSC2 associated with LTNB has been shown to be expressed in the placenta of mice. Many of the QTL regions showing associations coincided with previously identified QTL for fat deposition. This reinforces the role of fat regulation for lifetime reproductive traits. Overall, this whole-genome association study provides a list of genomic locations and markers associated with pig lifetime reproductive traits that could be considered for SPL in future studies.

Identification of genetic markers associated with fatness and leg weakness traits in the pig.

Pigs have undergone long-term selection in commercial conditions for improved rate and efficiency of lean gain. Interestingly, it has been observed in both experimental and field conditions that leg weakness has increased over time, concurrent with the selection for improved rate of lean gain, while fatter animals tend to have better leg action, and foot and leg (FL) structure. The exact molecular mechanisms or individual genes responsible for this apparent genetic correlation between fatness and leg weakness and other physical adaptability traits have been less well reported. Based on our recent studies involving candidate genes and leg weakness traits, the present investigation has identified 30 SNPs from 26 genes that were found to be associated with 10th rib backfat in a sow population consisting of 2066 animals. The specific alleles associated with increased backfat tended to be associated with better overall leg action, as shown for the genes including MTHFR, WNT2, APOE, BMP8, GNRHR and OXTR, while inconsistent associations with the single FL structure trait and backfat were observed for other genes. This study suggests that in some cases there may be a common genetic mechanism or linked genes regulating fatness and leg weakness. Such relationships are clearly complex, and the utilization of genetic markers associated with both traits should be treated cautiously.

Serum vitamin D metabolite concentrations in primary hyperparathyroidism.

Forty-nine patients with primary hyperparathyroidism were examined preoperatively and three months after parathyroid operation for their serum vitamin D metabolites and routine laboratory samples related to calcium metabolism. The preoperative serum 24,25-dihydroxyvitamin D level, mean (SE) was 1.86 (0.22) nmol/l and the postoperative level 5.35 (0.63) nmol/l, the difference being highly significant (P less than 0.001). Serum 1,25-dihydroxyvitamin D levels fell significantly (P less than 0.001) from a preoperative level of 175.5 (17.9) pmol/l to 102.8 (10.1) pmol/l postoperatively. The preoperative 25-hydroxyvitamin D level did not change significantly after surgery. The preoperative serum 24,25-dihydroxyvitamin D level was very low, especially in patients with bone disease while serum parathormone was significantly higher than in patients without bone disease.

Antihypertensive effect of diltiazem in a slow-release formulation for mild to moderate essential hypertension.

The antihypertensive efficacy and frequency of adverse reactions following administration of diltiazem in a new slow-release formulation were compared with placebo in 34 patients with mild to moderate essential hypertension in a randomized, double-blind, crossover study. After 6 weeks of treatment with diltiazem (240 or 360 mg/day), average supine blood pressure (BP) decreased from 165 +/- 21/101 +/- 5 mm Hg at baseline to 152 +/- 16/93 +/- 4 mm Hg compared with 160 +/- 19/100 +/- 7 mm Hg with placebo (p less than 0.01/p less than 0.001). Standing BP decreased from 162 +/- 20/107 +/- 6 mm Hg at baseline to 150 +/- 14/101 +/- 5 mm Hg compared to 159 +/- 18/107 +/- 8 mm Hg with placebo (p less than 0.01/p less than 0.001). The supine heart rate after diltiazem was 65 +/- 7 beats/min and after placebo 69 +/- 9 beats/min (p less than 0.01). There were no hematologic side effects. Only minor differences between diltiazem and placebo were observed in some of the biochemical laboratory values. Four patients were withdrawn due to side effects during treatment with diltiazem and 2 with placebo. Diltiazem in a slow-release formulation given twice a day lowered blood pressure significantly as monotherapy in patients with mild to moderate hypertension and was well tolerated.

Clinical and biochemical features in primary hyperparathyroidism.

Sixty-one consecutive patients were examined to determine the current mode of presentation of primary hyperparathyroidism (pHPT). Of these patients, 37.7% were asymptomatic, and the initial indication of pHPT was hypercalcemia, which was found unexpectedly on biochemical screening of the serum in elderly patients. Hypertension was twice as common among patients with pHPT as in the general population (36.1%). The next most common presentations were urinary calculi (18%) and mental depression (18%). The most useful discriminant laboratory tests were serum calcium, phosphorus, chloride, and parathormone (PTH). The calculated coefficient of correlation of PTH to land weight was high (r = 0.571, p less than 0.001). There was very significant correlation between PTH and seriousness of bone disease (r = 0.620, p less than 0.001). After parathyroidectomy, 3.3% of patients remained hypercalcemic, 93% were normocalcemic, and 1.6% were hypocalcemic.

Urinary glycosaminoglycan excretion in normal and stone-forming subjects: significant disturbance in recurrent stone formers.

The overnight (12 h) urinary excretion of glycosaminoglycans, citrate, magnesium, calcium and uric acid were measured in 82 normal subjects and 63 outpatients who had formed at least one urinary stone. No significant difference could be found between the two groups of unselected subjects with respect to any of the urinary parameters. Nonetheless, recurrent stone formers had significantly lower glycosaminoglycans and predictive risk index than normal controls.

Prevalence of urolithiasis in a Finnish district. An epidemiologic study of adults in Tampere.

Information on the prevalence of urolithiasis in a general population was obtained in an investigation of 5252 persons in the Finnish city of Tampere from September 1980 to February 1982. The study was based on a questionnaire delivered to every 37th citizen in the age groups 20-69 years and to 45-year-old and 65-year-old persons taking part in a health screening program. Persons with a history of urolithiasis were compared with healthy controls. The prevalence figures were 3.0% for men and 1.8% for women aged 20-69 years. The corresponding figures for the 45-year-old group were 4.2% and 1.2% and for the 65-year-old group they were 5.2% and 2.2%.