Determination of the sevoflurane sparing effect of methadone in cats

ObjectiveTo determine the magnitude and duration of sevoflurane minimum alveolar concentration (MAC) reduction following a single intravenous (IV) dose of methadone in cats.Study designProspective experimental study.AnimalsEight (four females and four males) healthy mixed-breed adult (1–2 years) cats weighing 5.82 ± 0.42 kg.MethodsAnesthesia was induced and maintained with sevoflurane. Intravenous catheters facilitated administration of methadone and lactated Ringer’s solution. After baseline MAC determination in triplicate using a tail clamp technique, 0.3 mg kg^?1 of methadone was administered IV. End-tidal sevoflurane concentration (e′SEVO) was reduced and MAC was redetermined. In an effort to determine the duration of MAC reduction, measurements were repeated in a stepwise manner until MAC values returned to baseline. After the last stimulation, the e′SEVO was increased to 1.2 individual MAC for 15 minutes, then sevoflurane was discontinued and cats were allowed to recover from anesthesia.ResultsBaseline sevoflurane MAC was 3.18 ± 0.06%. When compared with baseline the sevoflurane MAC after methadone administration was significantly reduced by 25, 15 and 7% at 26, 76 and 122 minutes, respectively. The final MAC value (3.09 ± 0.07%) determined 156 minutes after methadone administration was not significantly different from baseline.Conclusions and clinical relevanceIntravenous methadone (0.3 mg kg^?1) significantly decreased MAC of sevoflurane in cats but the effect was short-lived.     

Genetic analysis of the resistance to eight anthracnose races in the common bean differential cultivar Kaboon

Resistance to the eight races (3, 7, 19, 31, 81, 449, 453, and 1545) of the pathogenic fungus Colletotrichum lindemuthianum (anthracnose) was evaluated in F(3) families derived from the cross between the anthracnose differential bean cultivars Kaboon and Michelite. Molecular marker analyses were carried out in the F(2) individuals in order to map and characterize the anthracnose resistance genes or gene clusters present in Kaboon. The analysis of the combined segregations indicates that the resistance present in Kaboon against these eight anthracnose races is determined by 13 different race-specific genes grouped in three clusters. One of these clusters, corresponding to locus Co-1 in linkage group (LG) 1, carries two dominant genes conferring specific resistance to races 81 and 1545, respectively, and a gene necessary (dominant complementary gene) for the specific resistance to race 31. A second cluster, corresponding to locus Co-3/9 in LG 4, carries six dominant genes conferring specific resistance to races 3, 7, 19, 449, 453, and 1545, respectively, and the second dominant complementary gene for the specific resistance to race 31. A third cluster of unknown location carries three dominant genes conferring specific resistance to races 449, 453, and 1545, respectively. This is the first time that two anthracnose resistance genes with a complementary mode of action have been mapped in common bean and their relationship with previously known Co- resistance genes established.     

Association of RFLP markers with trait loci affecting clubroot resistance and morphological characters in Brassica oleracea L.

Summary Resistance to Plasmodiophora brassicae Wor. race 7, the causal agent of the disease clubroot, was examined in an F₂ population of a cross between a clubroot resistant broccoli (Brassica oleracea var. italica) and a susceptible cauliflower (B. oleracea var. botrytis). A genetic linkage map was constructed in the same population based on the segregation of 58 dispersed restriction fragment length polymorphism (RFLP) markers. Associations between the inheritance of RFLP marker genotypes and segregation for disease resistance, morphological and maturity characteristics were examined. For each triat examined, several chromosomal regions marked by RFLP probes appeared to contain trait loci, suggesting that each trait was under polygenic control. RFLP marker linkage to a major factor imparting dominance for clubroot resistance from the broccoli parent was observed in this population. Additionally, RFLP marker linkage to an independently segregating factor contributing clubroot resistance from the cauliflower parent was observed, indicating that it should be possible to use RFLP markers to facilitate selection of transgressive segregants having the combined resistance from both parental sources. In some instances, RFLP markers from the same or closely linked chromosomal regions were associated with both clubroot resistance and morphological traits. Analysis of RFLP marker genotypes at linked loci should facilitate the selection of desired disease resistant morphotypes.     

Glycoalkaloids of Solanum commersonii Dun. ex Poir

Five glycoalkaloids were identified from the aerial parts of wild Solanum commersonii Dun. ex Poir growing in Uruguay and their structures elucidated mainly by chemical and spectroscopic methods. In addition to the already known commersonine, demissine, tomatine and dehydrocommersonine, a new glycoalkaloid, identified as δ₅-demissine, solanid -5-en-3-O- {β-D-Glcp-(1→2)-[β-D-Xylp-(1→3) ]β-D-Glcp-(1→4)-β-D-Galp } was found. Tomatine and dehydrocommersonine have not been reported earlier as components of this plant. The glycoalkaloid composition found in the wild plants studied differ significatively from those described earlier, and have some implications in taxonomy and its use in potato breeding. This revised version was published online in July 2006 with corrections to the Cover Date.     

Genetic diversity of Phaeoisariopsis griseola in the State of Minas Gerais, Brazil

Due to the importance of common bean angular leaf spotin the state of Minas Gerais-Brazil and to the greatvariability of the pathogen, Phaeoisariopsisgriseola, monitoring races becomes an important toolfor breeding programs aiming at genetic resistance.The pathogenic variability of 30 isolates of the P. griseola, collected from various locations in thestate of Minas Gerais, was studied using the followingcommon bean differential series (Don Timóteo,Bolón Bayo, Montcalm, G 5686, Amendoin, G 11796,BAT 332, PAN 72, Cornell 49-242, México 54, Florde Mayo and G 2858). The first trifoliate leaf wasinoculated with a 2 × 10⁴ conidia/mL. Plants weremaintained at 20–22 ^°C and 95% relativehumidity for 48 hours. Symptom evaluation wasperformed 15 days after inoculation. Thirteen raceswere identified demonstrating the wide geneticvariability of the pathogen in the state of MinasGerais. Race 63.63 was the most virulent, whereas race63.23 was the most frequent (10 of 30 isolates), beingwidely distributed among the regions studied. Thevirulence phenotype indicated that the races studiedbelonged to the Mesoamerican group, which wasconfirmed when the 30 isolates were compared to Andeanand Mesoamerican standards using RAPD markers.     

Inhibition of development of exoerythrocytic forms of malaria parasites by gamma-interferon

A specific DNA probe was used to study the effect of recombinant rat, mouse, and human gamma-interferon (gamma-IFN) on the course of sporozoite-induced malaria infections. In mice and rats infected with sporozoites of Plasmodium berghei, mouse and rat gamma-IFN's strongly inhibited the development of the exoerythrocytic forms in the liver liver cells of the hosts, but not the development of the erythrocytic stages. The degree of inhibition of the exoerythrocytic forms was proportional to the dose of gamma-IFN administered, but was independent of the number of sporozoites used for challenge. A 30 percent reduction in the development of exoerythrocytic forms in rat liver was achieved when 150 units (about 15 nanograms of protein) of rat gamma-IFN were injected a few hours before sporozoite challenge; the reduction was 90 percent or more with higher doses of gamma-IFN. The effect was less pronounced if the gamma-IFN was administered 18 hours before or a few hours after challenge. Human gamma-IFN also diminished the parasitemia in chimpanzees infected with sporozoites of the human malaria parasite Plasmodium vivax. The target of gamma-IFN activity may be the infected hepatocytes themselves, as shown by in vitro experiments in which small doses of the human lymphokine inhibited the development of exoerythrocytic forms of Plasmodium berghei in a human hepatoma cell line. These results suggest that immunologically induced interferon may be involved in controlling malaria infection under natural conditions.     

Influence of medium‐chain triglycerides on consumption and weight gain in rats: a systematic review

The use of medium‐chain triglycerides (MCTs) has been studied for years in an attempt to elucidate their effects in food intake and body weight in animals. The aim of this study was to determine whether there is evidence that the use of MCT reduces consumption and body weight gain in rats, a species chosen as it has been widely used as an animal model in different surveys. A search of scientific work was performed in November 2011 on two bases: ‘Web of Science’ and ‘PubMed’. The terms sample size and homogeneity, randomisation, food consumption and weight gain, body composition, enzyme activity and hormonal activity in rats were used as selection criteria. Thirteen papers were selected after the refinement of the research. Twelve studies measured weight gain and among these, seven detected a decrease in weight gain and five found no differences. Twelve papers also measured food intake and among these, four detected a decrease in consumption, one detected an increase and seven found no differences. Based on established criteria for the ranking of scientific papers, it is concluded that there is strong evidence that MCTs can effectively reduce the consumption and subsequent weight gain of animals. However, in the long term, there may not be differences in results depending on the phenotypic adaptation of animals to a new metabolic condition.     

Effect of the type of farrowing room on the welfare and productive performance of lactating sows and of piglets during tropical winter

The objective of this study was to evaluate the behavior and performance of sows and piglets kept in different types of farrowing rooms: conventional farrowing room with jugglers and cages (CFR), CFR with a heated floor for the piglets alongside the sows (CFR+HF) and semi‐outdoor farrowing room without a cage or heating floor but with access to a fenced field (SFR) during the tropical winter. Twenty‐seven multiparous sows were allocated in three treatments and nine repetitions during 21 days. The relative humidity was higher at CFR and CFR+HF. The temperature of thigh and chest in contact with the floor and the neck were higher (P < 0.01) in conventional systems. Sows maintained in the CFR spent (P < 0.01) more time feeding and drinking. The heating floor increased (P < 0.01) the nursing behavior but did not affect (P > 0.09) the sows’ and piglets’ performances. SFR decreased the backfat thickness (P = 0.03) and lactation efficiency, but did not affect milk production (P > 0.12) or piglet performance (P > 0.09). It is concluded that during tropical winter, conventional farrowing systems ensure better piglet performance compared to SFR but this last seems to improve the behavior of sows. The heating floor favors nursing and does not affect the welfare of sows.