Effects of live feed containing Panagrellus redivivus and water depth on growth of Betta splendens larvae

Panagrellus redivivus is a nematode with a high protein content and low‐cost production. It is successfully used in the larviculture of shrimp, however, it has not yet been evaluated as feed for Betta splendens larvae. Thus, the objective of this study was to evaluate P. redivivus as feed for betta larvae maintained at different depths of water. The experiment was based on a completely randomized 3 × 2 factorial design, represented by two feed types and one alternating feeding regime plus two water depths (2.5 and 5.0 cm). The Artemia feed promoted the highest weight gain, followed by the alternating feeding regime. The single use of the nematode as live feed produced the poorest weight gain. The water depth and the feeding method influenced the specific growth rate (SGR). At a depth of 2.5 cm, the alternating feeding promoted similar SGR compared to fish fed with Artemia only. Furthermore, at the greater water depth an improvement in SGR was observed in fish fed Artemia only, but the similarity to alternating feeding regime remains. Thus, the inclusion of nematode is an appropriate and lower cost feed strategy for the betta larviculture independent of water depths.     

Microbial biomass as an antioxidant for tilapia feed

Microbial biomass (MB) produced by different industries is thought to be a beneficial supplement in fish feed due to high contents of antioxidants and pigments. However, little is known about their impact on fish health. In this experiment, 960 tilapia (26.84 ± 1.03 g) were fed one of eight experimental diets—a control diet with no MB (C), a control diet with vitamin E (VE) and six diets with three types of MB at two concentrations (0.25% and 0.5%): Rubrivivax gelatinosus (RG25 and RG50), Spirulina platensis (SP25 and SP50) and Saccharomyces cerevisiae (SC25 and SC50). Adding MB to diets decreased plasma total oxidant status, malonaldehyde and leucocyte respiratory burst; increased the total antioxidant status; and did not affect the blood biochemical parameters. In flesh, the use of the MB lowered the thiobarbituric acid‐reactive substances and increased redness (except for SC) and carotenoid deposition (except SC25). So, it was concluded that the use of the MB provided an antioxidant effect in tilapia blood plasma, decreased lipid oxidation and increased pigmentation and carotenoid deposition in the fish flesh, without imparting a negative impact on the animals’ health.     

Micropropagation of <Emphasis Type="Italic">Eucalyptus grandis</Emphasis> × <Emphasis Type="Italic">E. urophylla</Emphasis> AEC 224 clone

Genetic transformation systems require protocols that allow regenerating transgenic plants from transformed tissues. This study aimed to establish a protocol for indirect organogenesis in leaf explants of a Eucalyptus grandis  ×  E. urophylla AEC 224 clone. During callogenesis stage, several concentrations of NAA and then NAA or 2,4-D combined with TDZ were tested in JADS culture medium for 30 days, followed by subculture of the explants in the regeneration medium, containing 5.0 µM BA and 0.5 µM NAA for another 30 days. In these media, the explant oxidation rate was high (95 %). Thus, in order to reduce oxidation, different culture media were compared: WPM, MS, JADS and modified QL, followed by explant transfer onto regeneration medium. The highest percentage of regeneration and the lowest oxidation rate were achieved on WPM medium. Then, NAA and 2,4-D were tested in combination with TDZ and also TDZ and BA combined with NAA in WPM medium. The most efficient culture media in terms of shoot regeneration were WPM supplemented with 0.25 µM TDZ and 0.1 µM NAA during 30 days for callus induction and then with 5.0 µM BA and 0.5 µM NAA for another 30 days. This protocol yielded a regeneration rate of 43 %, with a low oxidation of tissues. A rooting experiment was conducted using half strength MS medium and comparing three concentrations of IBA (2.46, 4.90 and 7.35 µM). The highest rooting percentage (35 %) was obtained on medium containing 2.46 µM IBA. Once the shoots were rooted, acclimatization in a greenhouse was not challenging and plant survival reached 100 %.     

Validation of the Italian version of the UNESP–Botucatu unidimensional composite pain scale for the assessment of postoperative pain in cattle

Objective

The aim of this study was to validate the Italian version of the UNESP–Botucatu Unidimensional Composite Pain Scale (UCPS-IV) for assessing postoperative pain in cattle.

Predatory activity of the nematophagous fungus <Emphasis Type="Italic">Duddingtonia flagrans</Emphasis> on horse cyathostomin infective larvae

This work was performed to determine the predatory capacity in vitro of the nematophagous fungus Duddingtonia flagrans (isolate AC001) on cyathostomin infective larvae of horse (L₃). The experimental assay was carried out on plates with 2% water-agar (2% WA). In the treated group, each plate contained 1.000 L₃ and 1.000 conidia of the fungus. The control group without fungus only contained 1.000 L₃ in the plates. Ten random fields (4 mm diameter) were examined per plate of treated and control groups, every 24 h for seven days under an optical microscope (10× and 40× objective lens) for non-predated L₃ counts. After 7 days, the non-predated L₃ were recovered from the Petri dishes using the Baermann method. The interaction there was a significant reduction (p < 0.01) of 93.64% in the cyathostomin L₃ recovered. The results showed that the D. flagrans is a potential candidate to the biological control of horse cyathostomin L₃.     

Predatory activity of Pochonia chlamydosporia fungus on Toxocara (syn. Neoascaris) vitulorum eggs

Toxocara (Neoascaris) vitulorum is a gastrointestinal nematode parasite of young ruminants, responsible for high mortality rates in parasitized cattle and buffalo calves. The objective of this work was to compare the predatory capacity under laboratory conditions of four fungal isolates of the nematophagous fungus Pochonia chlamydosporia (VC1, VC4, VC5 and VC12) on T. vitulorum eggs in 2% water-agar (2% WA). T. vitulorum eggs were plated on 2% WA Petri dishes which contained cultured fungal isolates and control plates without fungi. After 10 and 15 days one hundred eggs were removed and classified according to the following parameters: type 1, biochemical and physiological effect without morphological damage to the eggshell, type 2, lytic effect with morphological alteration of the eggshell and embryo and type 3, lytic effect with morphological alteration of eggshell and embryo in addition to hyphal penetration and internal egg colonization. The fungal isolates were effective in the destruction of T. vitulorum eggs presenting the type 3 effect at 10 and 15 days after contact with the fungus. No nematophagous fungi were observed in the control group during the experiment. There was no variation in the predatory capacity of the fungal isolates (P?>?0.01) at the intervals of 10 and 15 days. These results indicate that P. chlamydosporia (VC1, VC4, VC5 and VC12) negatively influenced the development of T. vitulorum eggs and can be considered a potential candidate for the biological control of nematodes.     

Ground peach pits: alternative substrate component for seedling production

The exploitation of agro-industrial wastes is a strategy to add value to seedling production and reduce environmental problems.The production chain for processed peaches generates,approximately,21,000 tons of fruit worldwide,and the pits are used mainly to generate energy.The objective of the study was to investigate the use of different proportions of ground peach pits(GPP)as a substrate component for seedling growth of Eucalyptus dunnii in the nursery and field.Different proportions of GPP mixed with either commercial substrate(CS)or with brown peat(BP)were tested.The physical and chemical properties of the substrates,the morphological and physiological attributes of the seedlings and their correlation with substrate properties were evaluated.The GPP increased the density,aeration space and pH and reduced total porosity,liquid retention and electric conductivity of the substrate.The use of this component resulted in hormesis,a biphasic dose–response model in which low levels of exposure to this component stimulated biological performance of plants and high levels of exposure inhibited performance.For improved seedling growth in the nursery and adequate post-planting development of E.dunnii,GPP with CS is recommended at 20%of the total substrate and with BP between 15 and 30%.     

Amino acid digestibility in low-fat distillers dried grains with solubles fed to growing pigs

The objective of this experiment was to determine the standardized ileal digestibility（SID） of amino acids（AA） in 3sources of distillers dried grains with solubles（DDGS） with different concentrations of fat.Twelve growing barrows（initial body weight：76.1 ± 6.2 kg） were randomly allotted to a replicated 6×4 Youden square design with 6 diets and 4 periods.The fat content of the 3 sources of DDGS were 11.5,7.5,and 6.9%respectively.Diets contained 60%DDGS and fat concentration of the diets were 7.5,52,and 5.2%,respectively.Two additional diets containing the 2sources of DDGS with 75 and 6.9%fat were also formulated,and corn oil was added to these diets to increase the concentration of fat in the diets to levels that were calculated to be similar to the diet containing conventional DDGS with 11.5%fat.A N-free diet was also formulated to calculate endogenous losses of crude protein（CP） and AA from the pigs.Pigs were fed experimental diets during four 7-d periods.The first 5 d of each period were an adaptation period and ileal digesta were collected on d 6 and 7 of each period.The apparent ileal digestibililty（AID） and SID of CP and all indispensable AA,except AID Pro and SID of Trp,were greater（P 〈 0.01） in conventional DDGS than in the 2 sources of DDGS with reduced fat.Adding oil to the diets containing the 2 sources of DDGS with reduced fat did not consistently increase SID of AA.In conclusion,conventional DDGS has greater SID values for most AA compared with DDGS that contains less fat and inclusion of additional oil to diets containing low-fat DDGS does not increase AID or SID of AA.The lower AA digestibility in low-fat DDGS could not be overcome by the inclusion of additional fat to the diets.     

Cercosporiosis resistance in coffee germplasm collection

Cercosporiosis, or brown eye spot, is currently one of the main diseases of the coffee tree. It is caused by Cercospora coffeicola Berk. & Cooke. Nevertheless, genetic resistance to this disease has not yet been explored in any depth. Our objectives (a) were evaluate the response of 124 accessions from the germplasm collection of the Minas Gerais State (GC), Brazil, and eight commercial cultivars of C. arabica to cercosporiosis and (b) determine the best way to perform early progenies selections via controlled greenhouse experiments. Three controlled greenhouse experiments (1–3) were run in different seasons to determine the best way to proceed the selection. The seedlings were inoculated with a four isolates mixture obtained from different regions. The experimental data were analyzed individually (1–3), in a joint analysis, and as repetitions of a randomized complete block design. In each analysis we estimated genetic parameters and E-BLUP (empirical best linear unbiased predictor) genotypic values of the access. There was genetic variability to C. coffeicola resistance among the coffee tree accessions germplasm collection. Therefore, genetic improvements could be obtained by selection. Experimental repetitions in different seasons increase the selection efficiency and reliability of resistant genotypes with low cercosporiosis severity. The genotype Sarchimor MG 8840 showed the highest resistance level followed by Guatenano and the Timor Hybrid UFV 377-34, Timor Hybrid UFV 376-14 BE 5, and Wush–Wush × Timor Hybrid UFV 366-08.