Nutritional interventions to prevent and rear low‐birthweight piglets

Selection for hyperprolific sows, as a means of increasing litter size and profit, has resulted in an increased number of low‐birthweight (LBW) piglets. These LBW piglets might suffer from increased morbidity and mortality during the early neonatal period. In addition, they show reduced growth performance, meat and carcass quality, which leads to an important economic loss for the farmer in the post‐natal period. Therefore, nutritional interventions can be undertaken to prevent and rear LBW piglets. In the first part of this review, the preventive strategies at the sow level will be discussed. Approaches in preventing LBW piglets are to optimize the intrauterine environment via supplementing the sow during gestation. In the second part of this review, the interventions at the piglet level will be described. To increase the survival and growth rates of LBW piglets, one must focus on ensuring adequate colostrum and milk intake. Interventions include supplementing piglets, split nursing, split weaning and cross‐fostering. Additional interventions increasing the probability of optimal post‐natal food intake will be discussed.     

Evaluation of an indirect enzyme-linked immunosorbent assay (ELISA) for detection of antibodies to the Apx toxins of Actinobacillus pleuropneumoniae

The reference strains of the 12 serotypes of Actinobacillus pleuropneumoniae express one or two of three different RTX exotoxins designated Apx I, Apx II and Apx III. The toxins are important virulence factors. In the present study, ELISAs with purified Apx I, Apx II and Apx III, respectively, as antigen were evaluated as candidates for serological diagnosis of Actinobacillus pleuropneumoniae infection in pigs. The pigs were inoculated with biotype 1, serotypes 1-12, and biotype 2, serotype 14, respectively. A strong humoral antibody response was seen to all the three antigens in most pigs irrespective of the serotype used for inoculation. However, titers to the exotoxins secreted by the serotype used for inoculation were generally highest. The results show that toxin proteins of Actinobacillus pleuropneumoniae are antigenically related and that a correlation between serotype and secretion of exotoxin is not revealed serologically in the ELISA test.     

Protected wading bird species threaten relict centenarian cork oaks in a Mediterranean Biosphere Reserve: A conservation management conflict

Conservation management conflicts frequently arise when an overpopulation of a protected organism has negative effects on other valuable elements in the same ecosystem. We studied the interactions between a colony of protected tree-nesting wading birds and a remnant population of centenarian cork oaks that was part of the formerly dominant forests in the Doñana Biological Reserve (SW Spain). A significant increase in the tree mortality rates has been recorded in areas that are yearly influenced by the bird colony.We analysed a cohort of surviving trees using a gradient of nesting bird influence. Tree-nesting history, bird isotopic signature (δ¹⁵N), tree health-related parameters (defoliation, δ¹³C and leaf surface coverage by faeces) and several soil variables were evaluated. Bird influence was related to increased soil salinity. This increase correlated to increased water-use efficiency for the leaves and to crown defoliation, suggesting that the heavily occupied trees are under higher stress and in poorer health condition than the unoccupied ones. We tested structural equations models (SEM) that were based on hypothesised bird effects on the health of the trees. Soil-mediated effects of the nesting birds best explained the symptoms of the declining health of the trees, whereas the percent of leaves’ surface that was covered by faeces did not improve the fitted SEM model.For the reserve’s managers, a challenging trade-off exists between preserving the relict trees, which have a high genetic diversity and a key ecological role in these savannah-like ecosystems, and maintaining the current nesting area for these protected, but expanding, wading birds.     

Detection of Mycobacterium avium ssp. paratuberculosis in ileocaecal lymph nodes collected from elderly slaughter cows using a semi-nested IS900 polymerase chain reaction

The aim of this study was to investigate the occurrence of subclinical Mycobacterium avium spp. paratuberculosis (MAP) infections at slaughter by testing ileocaecal lymph nodes with a semi-nested IS900 PCR. Tissue samples were available within the framework of a parallel study investigating BSE-susceptibility factors in members of BSE-cohorts in the German Federal State of Lower Saxony. Ileocaecal lymph nodes were collected over a 2-year sampling period from 99 slaughter cattle of a mean age of 6.5 years (5.5-7.5 years). A recently developed IS900 semi-nested polymerase chain reaction (snPCR) assay offering a sensitivity of 1 genome equivalent was used for the detection of MAP-DNA. Based on this snPCR, 17 out of the 99 samples gave positive results, indicating a MAP occurrence of 17.17% in the random sample. All PCR products were sequenced for screening of polymorphisms. Nucleotide homologies of 98.5-100% were found with respect to the MAP K10 reference sequence IS900 (GenBank: AE16958). PCR analysis of ileocaecal lymph nodes collected from slaughter cattle proved to be a suitable technique to determine MAP occurrence in the local cattle population.     

Inactivation of TNF signaling by rationally designed dominant-negative TNF variants

Tumor necrosis factor (TNF) is a key regulator of inflammatory responses and has been implicated in many pathological conditions. We used structure-based design to engineer variant TNF proteins that rapidly form heterotrimers with native TNF to give complexes that neither bind to nor stimulate signaling through TNF receptors. Thus, TNF is inactivated by sequestration. Dominant-negative TNFs represent a possible approach to anti-inflammatory biotherapeutics, and experiments in animal models show that the strategy can attenuate TNF-mediated pathology. Similar rational design could be used to engineer inhibitors of additional TNF superfamily cytokines as well as other multimeric ligands.     

High dietary energy level stimulates growth hormone receptor and feed utilization in large Atlantic salmon (Salmo salar L.) under hypoxic conditions

This study examines how appetite and growth regulation of Atlantic salmon are affected by low dissolved oxygen (LO) and dietary digestible energy levels (DE: high [HE] vs. low [LE]). Long‐term exposure to LO resulted in a reduced feed intake, growth, digestible protein and fat retention efficiencies and increased feed conversation ratio and plasma ghrelin concentrations (p < .05) compared to high dissolved oxygen (HO). Pair‐feeding of rations based on the feed intake of the LO groups, but fed at HO, resulted in a 50% growth improvement in HE diet groups. This suggests that the poor growth under LO was not entirely caused by the reduced feed intake. Salmon adapted to LO by increased haemoglobin concentrations, while osmoregulation was affected by increased plasma chloride concentrations (p < .05). Plasma ghrelin concentration was unaffected by DE (p > .05). Growth regulation was affected by the HE diet, with increased liver and muscle growth hormone receptor ghr1 mRNA (p < .05), regardless of oxygen level. The growth depression due to low oxygen appears to be related to higher metabolic costs, while higher DE upregulates the GH‐IGF system at the ghr1 level and found to be beneficial for growth, feed intake, oxyregulation and osmoregulation under hypoxia.     

Dynamics of the change in free blood serum amino acids of broiler chicks under the effect of lithium salts

The effect of lithium glycinate on the adaptive compensatory reaction in poultry during vaccinal stress is studied and its use as a stress protector is suggested.     

Assessment of Genetic Diversity in Upland Cotton (<Emphasis Type="Italic">Gossypium hirsutum</Emphasis> L.) Breeding Lines by using Amplified Fragment Length Polymorphism (AFLP) Markers and Morphological Characteristics

Genetic diversity in 24 advanced breeding lines of cotton was studied by using six amplified fragment length polymorphism (AFLP) primer-pairs and 14 morphological characters. The six selected AFLP primer-pairs generated a total of 535 amplification products, of which 460 were found to be polymorphic resulting in 85.9% polymorphism. The observed genetic distances using AFLP markers ranged from 30% to 87% with an average of 34%. A wide range of variability was observed for all the morphological traits studied. The range in taxonomic distance was from 0.60 to 2.77. Most of the lines could be clustered in two major clusters in both the analyses. But the correlation coefficient between the pair-wise distances estimated from AFLPs and the average taxonomic distances estimated from morphological characters was found to be 0.04. UPGMA cluster analysis revealed inconsistencies in the clustering patterns, as the co-phenetic correlation coefficient between the dendrograms for morphological and AFLP data indicated a poor fit for the two data types. From combined information, genotypes ‘RST-12’, ‘H 1226’, ‘P 348’, ‘KDCAKD’, ‘CISV 24’ and ‘H1222’ were found to be distinct from rest of the material.     

Establishment and dissemination of hypovirulent strains of Cryphonectria parasitica in Greece

Chestnut blight caused by Cryphonectria parasitica has been one of the major reasons for the decline of chestnut cultivation in Greece over the last 50 years. A previous detailed study of the vc types of the fungus has revealed only four vc types in the entire country, those of EU‐1, EU‐2 and EU‐10 with the dominant being EU‐12 counting for 88% of the isolates. As the loss in orchard trees reached in some chestnut producing prefectures over 35% of the trees, the decision was taken to apply biological control on a nationwide scale. The project was implemented in 17 prefectures during the period 2007–2009. Hypovirulent (hv) strains of C. parasitica which were infected by the CHV‐1 subtype I (Italian subtype) viruses which occur naturally in Greece were used. The necessary hypovirulent inoculum was prepared at the Forest Research Institute during the period 2007–2009 on a large scale, however, with laboratory care. Three million inoculations were made around accessible developing cankers over three consecutive years by trained personnel. An extensive evaluation conducted in 2011 in the 12 of the 17 treated prefectures, where no natural hypovirulence had been found before, demonstrated not only the successful establishment of hypovirulence but also profound dissemination and healing of non‐inoculated cankers. The extent of dissemination varied significantly among sampling plots and among prefectures. The conclusion is drawn that CHV‐1 subtype I has successfully established and spread into chestnut orchards and coppice forests resulting in a gradual decline of chestnut blight.