Changes in pig diet particle size profile and nutrient content during on-farm storage and distribution to the feeders

The present study assessed the effect of silo emptying and feed transport by conveyor systems on particle size and nutrient content of the feed delivered to the pigs. Experiment 1 sampled feed from four feeders along the conveyor system of two barns. Samples were taken immediately after filling the feed silo (Begin) and when the silo was almost empty (End). In Experiment 2, three barns with drag-type conveyors, three with auger-type conveyors and two with spiral-type conveyors were sampled. Along the different conveyors, samples at 10, 20, 50 and 85 m distance from the feed silo were taken from the feeders. In each barn, sampling was repeated for two subsequent batches of feed delivered. In all samples, particle size profile was determined and nutrient content was analysed. In Experiment 2, mineral content was also determined. In Experiment 1, the size of the different particle fractions decreased from Begin to End. An interaction (p < 0.05) between sampling time and conveyor type was detected for the 10% smallest particles. In Experiment 2, an effect of sampling time on the 10% largest particles was detected (p < 0.05). The effect of sampling time on several nutrients was observed in Experiments 1 and 2, but the affected nutrients differed between both experiments. Results implied that it was mainly emptying of the silo that affected mash particle size profile and nutrient content. The potential impact of these changes on pig performance requires further investigation.     

Effect of avoparcin on performance,body composition and meat quality of finishing bulls

Three experiments were carried out with Belgian white-blue bulls housed in tie stalls. They received maize silage in the first trial and maize silage supplemented with a restricted amount of potatoes in two other trials. Besides the basal feed an appropriate concentrate was given at 7.5 g per kg liveweight per day. In Experiments I and II half the animals received 150 mg avoparcin per kg concentrate. In Experiment III, three concentrates were administered, containing 0, 75 and 150 mg avoparcin per kg.For the three trials, daily gain amounted to 1.07 and 1.08 kg; 1.11 and 1.07 kg; and 1.11, 1.14 and 1.13 kg, respectively, for the control and avoparcin-fed animals. Treatment differences were not significant. Daily feed intake was depressed from 75.6 to 73.3 g; 75.9 to 71.9 g; and from 75.3 to 72.9 and 71.4 g dry matter per kg W^0.75, respectively. Avoparcin improved dry matter consumption per kg gain by 4% in Experiment I, 3% in Experiment II and 6 and 7% in Experiment III. Differences in intake were significant only in Experiment III (P<0.05). Carcass parameters did not differ significantly and meat quality characteristics were mostly very similar.     

Constraints on the tailflick assay: morphine analgesia and tolerance are dependent upon locus of tail stimulation

In three experiments, the locus of tail stimulation in the tailflick assay was found to be an important parameter in determining morphine action. Rats were intravenously infused (Experiment I), injected with morphine subcutaneously (Experiment II), or implanted subcutaneously with morphine pellets (Experiment III). Analgesia was evaluated periodically following drug administration using the tailflick test and 3 adjacent 1 in. tail areas. In all three experiments, the distal tail section was more sensitive to the analgesic effects of morphine than more proximal sections. In Experiments I and III, tolerance to the effects of morphine developed more slowly at the distal tail location. These results indicate that the locus of stimulation in the tailflick assay can profoundly affect the development of analgesia and tolerance to morphine.     

Realtion of heart rate control to heartbeat perception

The relation of heartbeat perception to voluntary control of heart rate (HR) and to learning of enhanced HR control during feedback was studied in three experiments. In Experiment I heartbeat perception was unrelated to voluntary control of HR but was negatively correlated with HR learning. Experiments II and III showed that heartbeat perception was unrelated to either initial voluntary control or learning and suggested that sampling error accounted for the negative correlation in Experiment I. Experiment I also demonstrated that learned increases in HR are retained for at least 10 weeks following feedback training. Autonomic Perception Questionnaire scores were not predictive of voluntary HR control or learning.     

Relation of heart rate control to heartbeat perception

The relation of heartbeat perception to voluntary control of heart rate (HR) and to learning of enhanced HR control during feedback was studied in three experiments. In Experiment I heartbeat perception was unrelated to voluntary control of HR but was negatively correlated with HR learning. Experiments II and III showed that heartbeat perception was unrelated to either initial voluntary control or learning and suggested that sampling error accounted for the negative correlation in Experiment I. Experiment I also demonstrated that learned increases in HR are retained for at least 10 weeks following feedback training. Autonomic Perception Questionnaire scores were not predictive of voluntary HR control or learning.     

Effects of dietary conjugated linoleic acid supplementation on performance and immune function of weaned pigs

Two experiments were conducted to evaluate the effect of dietary conjugated linoleic acid (CLA) on performance and immune responses of weaned pigs. In Exp. I, 72 crossbred pigs weaned at 19 to 23 days of age and weighing 7.20 +/- 0.11 kg were randomly allotted to four diets supplemented with CLA at 0, 1, 2 or 3%. On day 14, pigs were injected with ovalbumin (1mg per kg BW) and blood samples were collected on day 7 and 14 after injection to test the specific OVA antibody. In Exp. II, 36 crossbred pigs weaned at 26 to 30 days of age and weighing 8.12 +/- 0.14 kg were randomly divided into two diets containing either 0 or 2% CLA. On day 14 and 28, blood samples were obtained to determine the lymphocyte proliferation and PGE2 levels in both trials, and CD4+, CD8+ T cells subsets and interleukin-1beta production were tested in Exp. II. In Exp. I both average daily gain and average daily feed intake of weaned pigs were improved quadratically and feed efficiency was increased linearly by CLA supplementation. Lymphocyte proliferation response to concanavalin A was increased quadratically as dietary CLA concentration increased on day 14 and 28. Ovalbumin antibody production levels were increased linearly on day 7 after injection of ovalbumin and increased quadratically on day 14 after injection, which follows the increased CLA levels, whereas CLA reduced linearly the production of prostaglandin E2 (PGE2). The results of Exp. II indicated that CLA improved performance, lymphocyte proliferation, and increased the CD8+ lymphocyte population, while reduced the production of PGE2 and interleukin-lbeta (IL- 1beta). These results suggest that the supplementation of CLA enhanced lymphocyte proliferation function, possibly by regulating the PGE2 production, and improved growth performance of pigs. Further studies are needed to determine the mechanism of CLA-induced inhibition of IL-1beta production.     

不同铁源对哺乳仔猪生长、代谢和环境的影响

为了探索不同铁源对哺乳仔猪生长、代谢和环境的影响,选用15窝共158头哺乳仔猪随机分为Ⅰ、Ⅱ、Ⅲ组,分别饲喂含硫酸亚铁、柠檬酸铁和蛋氨酸铁的3种饲粮(饲粮铁含量为146mg·kg-1)进行补铁效果试验.结果表明,Ⅱ、Ⅲ组仔猪在35日龄试验结束时的体重、日增重、体况行为等级、血液血红蛋白值、血浆转铁蛋白含量、血浆和肝脏铁含量等指标均显著(P<005或P<001)高于Ⅰ组;饲料消耗、腹泻发生率、排粪量、粪中含铁量和排铁量则显著(P<005或P<001)低于Ⅰ组.Ⅲ组35日龄体重和日增重也显著(P<005)高于Ⅱ组,但其余指标在Ⅱ组和Ⅲ组之间无显著差异(P>005),说明蛋氨酸铁和柠檬酸铁可明显改善仔猪的健康状况、生长发育、饲料报酬和血液生理生化指标,促进铁在猪体内的吸收和利用,降低排粪量和粪中排铁量,不失为给哺乳仔猪补铁的高效而安全的铁源     

Effect of Dietary Supplementation With α-Galactosidase Preparation and Stachyose on Growth Performance,Nutrient Digestibility and Intestinal Bacterial Populations of Piglets

Two experiments were conducted to investigate the effect of dietary supplementation with f -galactosidase preparation and stachyose on growth performance, nutrient digestibility and intestinal bacterial populations of piglets. In Experiment I 72 crossbred piglets were allotted to three treatments, i.e. 1) control (basal) diet, 2) f -Gal1 and 3) f -Gal5, the basal diet supplemented with 0.01% and 0.05% f -galactosidase preparation ( f -Gal), respectively. Average daily gain, average daily feed intake and feed conversion ratio were not influenced by f -Gal supplementation. In Experiment II 72 crossbred weanling piglets were randomly assigned to four treatments with a complete factorial design, i.e. 1) basal diet, 2) basal diet with 0.01% f -Gal supplementation, 3) basal diet with 1% stachyose supplementation and 4) basal diet with 1% stachyose and 0.01% f -Gal supplementation. Average daily gain and feed conversion ratio were influenced by f -Gal and stachyose supplementation. The ileal digestibility of stachyose, raffinose, gross energy and crude protein was improved significantly by f -Gal supplementation. The microbial populations in the intestine were modified by both f -Gal and stachyose supplementation. The data suggested that stachyose supplementation had an adverse effect on the growth performance of piglets and f -Gal supplementation could ameliorate it, especially in younger pigs.     

Field tests of micropatch and prey-size selection by Snail Kites Rostrhamus sociabilis

Six free-living Snail Kites Rostrhamus sociabilis were tested for preference by density for micropatches and size of apple snails Pomacea dolioides in simultaneous choice situations. Two hypotheses were tested: kites respond differentially to varying densities of larger versus smaller size classes of snails, foraging where the expected yield is greater; and kites are capable of selecting the larger size classes from a variety of available snail size classes. Kites preferred to forage in micropatches with high prey density. Variation among kites with respect to prey-size selection was very small. In Experiments I and III there were significant inverse correlations between kite choice and snail size, but no relationship was demonstrated in the other test. Significant differences were found between mean individual weights of snails taken by kites and those not taken in Experiments I and III. No differences were observed in Experiment II. Selectivity indices show that the larger size classes were taken above their availability, although no statistical relationship existed between kite choice and snail abundance. These results corroborate the two hypotheses and suggest that kites use hierarchical decision making by employing density of snails to select appropriate feeding locations before selecting the largest individuals from those locations.     

Localization of superoxide anion production to mitochondrial electron transport chain in 3-NPA-treated cells

3-Nitropropionic acid (3-NPA), an inhibitor of succinate dehydrogenase (SDH) at complex II of the mitochondrial electron transport chain induces cellular energy deficit and oxidative stress-related neurotoxicity. In the present study, we identified the site of reactive oxygen species production in mitochondria. 3-NPA increased O2- generation in mitochondria respiring on the complex I substrates pyruvate+malate, an effect fully inhibited by rotenone. Antimycin A increased O2- production in the presence of complex I and/or II substrates. Addition of 3-NPA markedly increased antimycin A-induced O2- production by mitochondria incubated with complex I substrates, but 3-NPA inhibited O2- formation driven with the complex II substrate succinate. At 0.6 microM, myxothiazol inhibits complex III, but only partially decreases complex I activity, and allowed 3-NPA-induced O2- formation; however, at 40 microM myxothiazol (which completely inhibits both complexes I and III) eliminated O2- production from mitochondria respiring via complex I substrates. These results indicate that in the presence of 3-NPA, mitochondria generate O2- from a site between the ubiquinol pool and the 3-NPA block in the respiratory complex II.     

Evaluation of a Psychophysiologically Controlled Adaptive Automation System, Using Performance on a Tracking Task

Three experiments were conducted to evaluate the performance of a psychophysiologically controlled adaptive automation system. Subjects were asked to perform a compensatory tracking task while their electroencephalogram (EEG) was recorded and an engagement index was derived from the EEG, using the alpha, beta, and theta bandwidths: /( + ) and /. In Experiment I, EEG was recorded from three different sites: frontal, parietal, and temporal. Although tracking performance did not differ as a function of site, the number of task mode allocations was greater under a negative feedback contingency than under a positive feedback contingency. This effect was seen primarily from frontal sites. Experiments II and III evaluated the adaptive automation system, using extended runs under positive and negative feedback with either a slope (Experiment II) or absolute (Experiment III) criterion used to drive the system. Using either criterion, performance was found to be significantly better under negative feedback. Future evaluation and use of psychophysiologically controlled adaptive automation systems are discussed.     

Deletion of Von Willebrand A Domain Containing Protein (VWA8) raises activity of mitochondrial electron transport chain complexes in hepatocytes

VWA8 (Von Willebrand A Domain Containing Protein 8) is a AAA+ ATPase that is localized to the mitochondrial matrix and is widely expressed in highly energetic tissues. Originally found to be higher in abundance in livers of mice fed a high fat diet, deletion of the VWA8 gene in differentiated mouse AML12 hepatocytes unexpectedly produced a phenotype of higher mitochondrial and nonmitochondrial oxidative metabolism, higher ROS (reactive oxygen species) production mainly from NADPH oxidases, and increased HNF4a expression. The purposes of this study were first, to determine whether higher mitochondrial oxidative capacity in VWA8 null hepatocytes is the product of higher capacity in all aspects of the electron transport chain and oxidative phosphorylation, and second, the density of cristae in mitochondria and mitochondrial content was measured to determine if higher mitochondrial oxidative capacity is accompanied by greater cristae area and mitochondrial abundance. Electron transport chain complexes I, II, III, and IV activities all were higher in hepatocytes in which the VWA8 gene had been deleted using CRISPR/Cas9. A comparison of abundance of proteins in electron transport chain complexes I, III and ATP synthase previously determined using an unbiased proteomics approach in hepatocytes in which VWA8 had been deleted showed agreement with the activity assays. Mitochondrial cristae, the site where electron transport chain complexes are located, were quantified using electron microscopy and stereology. Cristae density, per mitochondrial area, was almost two-fold higher in the VWA8 null cells (P < 0.01), and mitochondrial area was two-fold higher in the VWA8 null cells (P < 0.05). The results of this study allow us to conclude that despite sustained, higher ROS production in VWA8 null cells, a global mitochondrial compensatory response was maintained, resulting in overall higher mitochondrial oxidative capacity.     

Relationship between concentrations of immunoreactive insulin-like growth factor-I in follicular fluid and various biochemical markers of differentiation in bovine antral follicles

Three experiments were conducted to determine the relationship between concentrations of insulin-like growth factor-I (IGF-I) in ovarian follicular fluid and various biochemical markers of follicular differentiation in bovine follicles. In Experiment I, ovaries were removed on Days 7, 14, 28, 42, or 56 after parturition from a total of 21 cows. In Experiment II, ovaries of 31 cows were removed between Days 20 and 30 postpartum after 48 or 96 h of either saline (0.9% NaCl, 5 ml) or luteinizing hormone-releasing hormone (LHRH, 500 ng/5 ml saline) injections given every 2 h via jugular cannulae. In Experiment III, ovaries of six cows were removed 48-50 h after a 35-mg injection of prostaglandin F2 alpha during the midluteal phase of an estrous cycle. In Experiments I and II, all follicles greater than or equal to 8.0 mm in diameter were removed from each ovary (n = 33 and 46, respectively). In Experiment III, fluid from all follicles greater than 4 mm in diameter were removed individually (n = 10), and fluid from follicles 1-4 mm in diameter were pooled for each cow. Follicles for each experiment were further categorized as either estrogen-active (E-A, concentration of estradiol greater than progesterone in follicular fluid) or estrogen-inactive (E-I, concentration of progesterone greater than estradiol in follicular fluid). Measurements of immunoreactive IGF-I (i-IGF-I) were made after separating IGFs from their binding proteins with an acid-ethanol extraction.(ABSTRACT TRUNCATED AT 250 WORDS)     

Separation of the alpha chains of type I and III collagens by SDS-polyacrylamide gel electrophoresis.

A method for the separation of type III collagen from type I collagen by SDS-polyacrylamide gel electrophoresis has been developed. This is based on the observation that the presence of 3-4 M urea decreases the mobility of the alpha 1 [III] chain to a greater extent than those of the alpha 1[I] and alpha 2 chains, although the alpha 1[I] and alpha 1[III] chains move at the same rate in the absence of urea. An attempt to separate the alpha 1[II] chain of type II collagen from the alpha 1[I] chain was unsuccessful under the experimental conditions employed.     

Photomovement of the red alga Porphyridium cruentum (Ag.) Naegeli

Photophobic reactions of the red alga Porphyridium cruentum have been studied by single cell observations and by population experiments with the light trap method. In white light traps photoaccumulation is saturated at about 6000 lx. Experiments with monochromatic light demonstrate the necessity of carefully separating the three basic light reactions, viz. phototaxis, photokinesis and photophobic response by an appropriate experimental set-up: In single-beam experiments trap wavelengths >695 nm cause photodispersal which is not due to photophobic entrance reactions, but is exclusively due to the positive photokinetic effect of the trap light. This photodispersal can be cancelled by a photokinetically active background light. In the short wavelength range not only photokinesis, but also phototaxis interferes with photophobic reactions thus affecting the density of photoaccumulations in the light trap. Phototactic and photokinetic interference can be avoided by a blue background light. The action spectrum measured this way indicates activity of photosystem I and photosystem II pigments in the perception of the step-down photophobic stimulus. Varying the wavelength of the background light at constant trap light absorbed mainly by photosystem I or photosystem II respectively, efficient spill-over of light energy from photosystem II to the light reaction of photosystem I could be demonstrated. From the results it is concluded that phobic reactions are induced by a decrease of the electron flow rate in the linear electron transport chain.     

Reduced Adolescent-Age Spatial Learning Ability Associated with Elevated Juvenile-Age Superoxide Levels in Complex I Mouse Mutants

Large-scale, heteroplasmic and generally pathogenic mtDNA defects (as induced by defective mitochondrial DNA polymerase, clonal mutations or DNA deletions) are known to negatively impact on life span and can result in apoptosis and tissue loss in, e.g., skeletal muscle or reduce learning abilities. The functional impact of homoplasmic specific mtDNA point mutations, e.g., in genes coding for the electron transport chain, however, remains a matter of debate. The present study contributes to this discussion and provides evidence that a single point mutation in complex I of the respiratory chain is associated with impairment of spatial navigation in adolescent (6-month-old) mice, i.e., reduced performance in the Morris Water Maze, which goes along with increased production of reactive oxygen species (ROS) in juvenile mice (3 months) but not at the age of phenotype expression. A point mutation in complex III goes along with only a mild and non-significant negative effect on cognitive performance and no significant changes in ROS production. These findings suggest to also consider the ontogenetic development of phenotypes when studying mtDNA mutations and highlights a possible impact of complex I dysfunction on the emergence of neurological deficits.     

Cell cycle analysis of in vitro cultured goral (Naemorhedus caudatus) adult skin fibroblasts

The present study was undertaken to examine cell cycle characteristics of endangered Goral (CITES Appendix I) adult skin fibroblasts. Seven experiments were performed, each with a one-way completely randomized design involving three replicates. Least significant difference (LSD) was used to determine variation among treatment groups. Experiment I focused on the effects of cycling, serum-starved, and fully confluent stages of Goral cells. In Experiments II and III, the effects of different antioxidants like beta-mercaptoethanol (beta-ME, 10 microM), cysteine (2 mM), and glutathione (2 mM) were examined after cells were fully confluent without serum starvation for 24 h and 4 h, respectively. In Experiments IV and V, three protease inhibitors, namely 6-dimethylaminopurine (6-DMAP, 2 mM), cycloheximide (7.5 microg/ml) and cytochalasin B (7.5 microg/ml), were used as in Experiment II. In Experiments VI and VII, the effect of different levels of dimethylsulphoxide (DMSO) at 0%, 0.5%, 1.0% and 2.5% were tested by flow cytometry (FACS). In Experiment I, 68.7% of Goral skin fibroblasts reached the G(0)/G(1) stage (2C DNA content) when subjected to the serum-starved medium, which was more than the cycling (64.9%) and fully confluent groups (61.0%) (P > 0.05). Among the chemically treated group, beta-ME, cysteine and DMSO showed better results for synchronization of G(0) + G(1) phases than cycling, serum-starved and fully confluent groups. It can thus be concluded that beta-ME, cysteine and DMSO at certain concentrations can synchronize the cell cycle effectively, which could have a positive impact on somatic cell nuclear transfer in the goral.     

Mitochondrial Complex II Can Generate Reactive Oxygen Species at High Rates in Both the Forward and Reverse Reactions

Respiratory complex II oxidizes succinate to fumarate as part of the Krebs cycle and reduces ubiquinone in the electron transport chain. Previous experimental evidence suggested that complex II is not a significant contributor to the production of reactive oxygen species (ROS) in isolated mitochondria or intact cells unless mutated. However, we find that when complex I and complex III are inhibited and succinate concentration is low, complex II in rat skeletal muscle mitochondria can generate superoxide or H(2)O(2) at high rates. These rates approach or exceed the maximum rates achieved by complex I or complex III. Complex II generates these ROS in both the forward reaction, with electrons supplied by succinate, and the reverse reaction, with electrons supplied from the reduced ubiquinone pool. ROS production in the reverse reaction is prevented by inhibition of complex II at either the ubiquinone-binding site (by atpenin A5) or the flavin (by malonate), whereas ROS production in the forward reaction is prevented by malonate but not by atpenin A5, showing that the ROS from complex II arises only from the flavin site (site II(F)). We propose a mechanism for ROS production by complex II that relies upon the occupancy of the substrate oxidation site and the reduction state of the enzyme. We suggest that complex II may be an important contributor to physiological and pathological ROS production.     

Behavioral chaining in the goat (Capra hircus)

Five male castrated goats were trained to perform a behavioral chain. In Experiment I the goats were trained to run in an indoor U-shaped runway. The chain consisted of jumping over three hurdles, walking on a raised walkway, running through two 55 gallon barrels and entering an operant chamber and pressing a response panel on a fixed ratio 10 for a food reward. In Experiment II, a larger outdoor runway was used and the components of the chain were reordered. Before the beginning of Experiment I the goats were trained by the method of successive approximations to press a response panel. It took five to seven 1 h sessions to shape this response. It took 16 sessions to train the goats to perform all components of the behaviour chain under stimulus control. Once the goats reached this point, there were no significant variations in performance of the operant task or the time to complete the chain. Although the serial and geometric arrangement of the components of the chain were altered in Experiment II, it took nine sessions to train the goat to perform the altered chain. The results of this study demonstrate that goats can be easily trained to perform a complex behavioral chain. Once the chain has been learned, the goats readily adapt to alterations in the arrangement of the components and the location of the runway.     

Apoptotic death in Leishmania donovani promastigotes in response to respiratory chain inhibition: complex II inhibition results in increased pentamidine cytotoxicity

The biochemical changes consequent to respiratory chain inhibition and their relationship to cell death in Leishmania spp. remain elusive. Inhibitors of respiratory chain complexes I, II, and III were able to induce apoptotic death of the bloodstream form of Leishmania donovani. Complex I inhibition resulted in mitochondrial hyperpolarization that was preceded by increased superoxide production. Limitation of electron transport by thenoyltrifluoroacetone and antimycin A, inhibitors of complexes II and III, respectively, resulted in dissipation of mitochondrial membrane potential that was sensitive to cyclosporin A, a blocker of mitochondrial permeability transition pore. Further studies conducted with thenoyltrifluoroacetone showed maximal generation of hydrogen peroxide with a moderate elevation of superoxide levels. Complex III inhibition provoked superoxide generation only. Interference with complex II but not complexes I and III increased intracellular Ca(2+). A tight link between Ca(2+) and reactive oxygen species was demonstrated by antioxidant-induced diminution of the Ca(2+) increase. However, chelation of extracellular Ca(2+) could not abrogate the early increase of reactive oxygen species, providing evidence that Ca(2+) elevation was downstream to reactive oxygen species generation. Ca(2+) influx occurred through nonselective cation and L-type channels and Na(+)/Ca(2+) exchanger-like pathways. Antioxidants such as glutathione and Ca(2+) channel blockers reduced apoptotic death. This study provides a new possibility that concurrent inhibition of respiratory chain complex II with pentamidine administration increases cytotoxicity of the drug. This increased cytotoxicity was connected to a 4-fold elevation in intracellular Ca(2+) that was pooled only from intracellular sources. Therefore, inhibition of complexes I, II, and III leads to apoptosis and complex II inhibition in parallel with pentamidine administration-enhanced drug efficacy.