2000 Nebraska Swine Report

This publication was prepared by the staff in Animal Science and cooperating Departments for use in Extension, Teaching and Research programs. It deals with the results that were done in reproduction, breeding, health, nutrition, economics and housing of swine

Letter to the Editor

I am a co-author of papers published in the Journal of Animal Science by Moeller et al. (2004) and Serenius et al. (2006) that report data from the National Pork Producers Council Maternal Line Evaluation project (MLE). In his letter to the editor, DeBuse (2007) claims that the authors of these papers misrepresented the line submitted by Newsham Hybrids (USA) Inc. (NH; Colorado Springs, CO) to the MLE. Below are the facts, as I know them, regarding the design and implementation of the MLE. The MLE tested crossbred females that represented maternal lines available to producers. It was designed to detect differences between lines for longevity traits, with probabilities of type 1 and type 2 errors of 0.05 and 0.75, respectively, requiring 531 females per line. The number of sires depended on the effective population size of the nucleus populations. Each participant was required to submit a minimum of 590 gilts per line to assure 531 breeding gilts. To assure that the nucleus populations were materially closed, 90% of the litters born during the last 5 years were required to have a sire that was born within the population, and 90% of the litters were required to have a dam that was born in the population

Crossbred Boars Can Be Used to Improve Reproductive Efficiency

Lack of sexual aggressiveness and infertility in boars are problems that have been experienced to some degree by nearly every swine producer. The impact of these problems on the efficiency of swine production depends on their frequency; but even relatively few boar reproductive problems can upset the production schedule of units that are farrowing continuously. Recent research provides convincing evidence that at 7 to 9 months of age crossbred boars are more aggressive breeders than purebreds and that conception rates are higher for females mated to crossbred boars. The purpose of this report is to examine the research that compares purebred and crossbred boars and to briefly evaluate the economic impact crossbred boars can have on the efficiency of production

CROSSBREEDING IN SWINE: EXPERIMENTAL RESULTS

A review of recent swine crossbreeding experiments is presented and integrated with earlier work. Variation among experiments in observed heterosis for specific crosses was large for reproduction and sow productivity traits. However, standard errors of estimates were also large. It seems likely that heterosis, expressed in absolute values or in percentage units, is different for specific crosses. It is unclear whether these differences are large enough to warrant the use of unique parameter values for comparisons of alternate mating systems. In addition to average heterosis values, average direct and maternal genetic effects are given

Did perception of the economy affect attitudes to immigration at the 2010 British General Election?*

Objective Immigration and the economy were the most salient issues in British politics at the 2010 general election, yet the relationship between them remains unclear. This article questions whether perception of the economic situation influenced hostility to immigration to Britain during the 2010 general election campaign. Method This article employs a logistic regression model using the 2010 British Election Study to test the effect of economic perception and other previously identified factors on hostility to immigration. Results The results show that perception of the economy did have an effect on hostility to immigration at the 2010 British general election. However, the effect is negligible. Conclusion The findings highlight the influence of other factors in predicting hostility to immigration, particularly identity and culture, party identification, and policy-based factors. The prominence of analyzing the effect of economic concerns in determining attitudes to immigration appears misplaced

Economic solutions are unlikely to ease immigration concerns

Immigration is a huge element of contemporary political debate, and it continues to divide and polarise opinion, while fuelling the rise of UKIP and other radical parties across Europe. Here, Craig Johnson and Sunil Rodger argue that while hostility to immigration may be in part to do with economics, a sunny economic outlook is unlikely to reassure immigration-sceptics of its worth

Plasma FSH Concentration in Young Boars and Gilts from Lines that Differ in Ovulation Rate and Litter Size

Four experiments were conducted to determine whether boars and gilts from selected lines that differ in ovulation rate and litter size also differ in plasma concentrations of Follicle Stimulating Hormone (FSH). Plasma FSH was studied because it is a potential indicator trait of ovulation rate. Plasma concentrations of FSH in young boars and gilts differed between the select and the control line. It is likely that this difference is due to a correlated response to selection for ovulation rate. Therefore, plasma concentration of FSH in young boars and gilts may be a trait that can be used effectively to indirectly select for ovulation rate. Additional data to more precisely estimate the genetic relationships are needed before selection for FSH is recommended

EC88-217 Crossbreeding Systems for Commercial Pork Production

Extension circular 88-217 is about crossbreeding system for commercial, pork production

The Impact of Residence Design on Freshman Outcomes: Dormitories Versus Suite-Style Residences

This study was designed to measure affective, behavioural, and cognitive variables in a sample of 3159 first-year students, and to compare these variables by the type of residence building in which the student lived. Students living in suite-style buildings reported a greater sense of belonging, and higher activity levels than students living in dormitory- style buildings. Furthermore, sense of belonging was predicted by high extraversion and low conscientiousness. This suggests that introverted, conscientious students living in traditional dormitory-style buildings may be most at-risk of feeling “out-of-place” in residence.Cette étude a été crée pour évaluer les variables émotionnelles, comportementales, et cognitives dans une panel de 3159 étudiants dans leur première année d’université, et pour comparer ces variables par le type d’édifi ce de résidence dans laquelle les étudiantes vivaient. Etudiants vivant dans les immeubles de style suite ont rapporte un sens d’appartenance plus grand, et des niveaux plus élevées d’activité que celles qui vivait dans les immeubles de style foyer. En plus, un sens d’appartenance a été prédit par haute extraversion et des niveaux bas de conscience. Cela suggère que les étudiants introverties et consciencieux qui vivent dans les immeubles traditionnelles de style foyer seront peut-être les plus exposer à sentir « hors-de-place ». &nbsp

Responses to 19 generations of litter size selection in the Nebraska Index line. I. Reproductive responses estimated in pure line and crossbred litters

Our objective was to estimate responses in reproductive traits in the Nebraska Index line (I) after 19 generations of selection for increased litter size. Responses were estimated in dams producing pure line, F1, and three-way cross litters. A total of 850 litters were produced over six year-seasons, including 224 pure line litters, 393 F1 litters produced from I and C females mated with DanbredNALandrace (L) or Duroc- Hampshire (T) boars, and 233 litters by F1 L x I and L x C females mated with T boars. Contrasts of means were used to estimate the genetic difference between I and C and interactions of line differences with mating type. Farrowing rates of lines I (û = 91.0%) and C (û = 92.8%) did not differ. Averaged across all genetic groups, mean number born alive per litter was 10.1 pigs, and number and weight of pigs weaned per litter, both adjusted for number nursed and weaning age of 12 d, were 9.7 pigs and 34.4 kg, respectively. Averaged across mating types, direct genetic effects of I were greater than C (P \u3c 0.05) for total born (3.53 pigs), number born alive (2.53 pigs), number of mummified pigs (0.22 pig), and litter birth weight (2.14 kg). The direct genetic effect of line I was less than C (P \u3c 0.05) for litter weaning weight (-1.88 kg). Interactions of line effects with crossing system were significant (P \u3c 0.05) for total number born, number of stillborn pigs, number weaned, and litter weaning weight. In pure line litters, I exceeded C by 4.18 total pigs and 1.76 stillborn pigs per litter, whereas the estimate of I–C in F1 litters was 2.74 total pigs and 0.78 stillborn pig per litter. The contrast between I and C for number weaned and litter weaning weight in pure litters was 0.32 pig and -0.28 kg, respectively, compared with 0.25 pig and -2.14 kg in F1 litters. Crossbreeding is an effective way to use the enhanced reproductive efficiency of the Index line