Effect of trehalose supplementation in milk replacer on the incidence of diarrhea and fecal microbiota in preweaned calves

Trehalose, a nonreducing disaccharide consisting of d-glucose with α,α-1,1 linkage, was evaluated as a functional material to improve the gut environment in preweaned calves. In experiment 1, 173 calves were divided into two groups; the trehalose group was fed trehalose at 30 g/animal/d with milk replacer during the suckling period, and the control group was fed nonsupplemented milk replacer. Medication frequency was lower in the trehalose group (P < 0.05). In experiment 2, calves (n = 20) were divided into two groups (control group [n = 10] and trehalose group [n = 10]) based on their body weight and reared under the same feeding regimens as in experiment 1. Fresh feces were collected from individual animals at the beginning of the trial (average age 11 d), 3 wk after trehalose feeding (experimental day 22), and 1 d before weaning, and the fecal score was recorded daily. Fecal samples were analyzed for fermentation parameters and microbiota. The fecal score was significantly lower in the trehalose group than in the control group in the early stage (at an age of 14 to 18 d; P < 0.05) of the suckling period. Calves fed trehalose tended to have a higher proportion of fecal butyrate on day 22 than calves in the control group (P = 0.08). Population sizes of Clostridium spp. were significantly lower (P = 0.036), whereas those of Dialister spp. and Eubacterium spp. tended to be higher in the feces of calves in the trehalose group on day 22 (P = 0.060 and P = 0.083). These observations indicate that trehalose feeding modulated the gut environment and partially contributed to the reduction in medication frequency observed in experiment 1.     

Evaluation of the efficacy of aquaculture feeds for the climbing perch Anabas testudineus: replacement of fishmeal by black soldier fly Hermetia illucens prepupae

Fisheries Science - The growth of the climbing perch Anabas testudineus reared on lower protein feeds with the replacement of fishmeal (FM) by prepupae of the black soldier fly (BSF) Hermetia...     

Annual monitoring of growth of red sea bream by multi-stereo-image measurement

Fisheries Science - In aquaculture, periodic measurement of fish body size is required to suitably assess growth progress. The aim of this study is to monitor the growth of free-swimming red sea...     

Comparative functional anatomy of hindlimb muscles and bones with reference to aquatic adaptation of the sea otter

Although the sea otter (Enhydra lutris) is a complete aquatic species, spending its entire life in the ocean, it has been considered morphologically to be a semi-aquatic animal. This study aimed to clarify the unique hindlimb morphology and functional adaptations of E. lutris in comparison to other Mustelidae species. We compared muscle mass and bone measurements of five Mustelidae species: the sea otter, Eurasian river otter (Lutra lutra), American mink (Neovison vison), Japanese weasel (Mustela itatsi) and Siberian weasel (M. sibirica). In comparison with the other 4 species, E. lutris possessed significantly larger gluteus, popliteus and peroneus muscles, but smaller adductor and ischiopubic muscles. The popliteus muscle may act as a medial rotator of the crus, and the peroneus muscle may act as an abductor of the fifth toe and/or the pronator of the foot. The bundles of the gluteus superficialis muscle of E. lutris were fused with those of the tensor fasciae latae muscle and gluteofemoralis muscles, and they may play a role in femur abduction. These results suggest that E. lutris uses the abducted femur, medially rotated crus, eversion of the ankle and abducted fifth digit or extended interdigital web as a powerful propulsion generator. Therefore, we conclude that E. lutris is a complete aquatic animal, possessing differences in the proportions of the hindlimb muscles compared with those in other semi-aquatic and terrestrial mustelids.     

Ligand-binding characteristics of feline insulin-binding immunoglobulin G

Polyclonal immunoglobulin (Ig) G autoantibodies against insulin have been identified in sera of healthy cats. We purified and fractionated insulin-binding IgGs from cat sera by affinity chromatography and analyzed affinity of insulin-binding IgGs for insulin and their epitopes. Following the passing of fraction A, which did not bind to insulin, insulin-binding IgGs were eluted into two fractions, B and C, by affinity chromatography using a column fixed with bovine insulin. Dissociation constant (KD) values between insulin-binding IgGs and insulin, determined by surface plasmon resonance analysis (Biacore™system), were 1.64e⁻⁴ M for fraction B (low affinity IgGs) and 2e⁻⁵ M for fraction C (high affinity IgGs). Epitope analysis was conducted using 16 peptide fragments synthesized in concord with the amino acid sequence of feline insulin by an enzyme-linked immunosorbent assay. Fractions B and C showed higher absorbance (affinity) of the peptide fragment of 10 amino acid residues at the carboxyl-terminal of the B chain (peptide No. 19), followed by peptide fragments of 6 to 15 amino acid residues of the B chain (peptide No. 8). Fraction C showed a higher absorbance to 7 to 16 amino acid residues of the B chain (peptide No. 5) compared with the absorbance of fraction B. Polyclonal insulin-binding IgGs may form a macromolecule complex with insulin through the multiple affinity sites of IgG molecules. Feline insulin-binding IgGs are multifocal and may be composed of multiple IgG components and insulin.     

Hypoxia inducible factor 1α expression and effects of its inhibitors in canine lymphoma

Hypoxic conditions in various cancers are believed to relate with their malignancy, and hypoxia inducible factor-1α (HIF-1α) has been shown to be a major regulator of the response to low oxygen. In this study, we examined HIF-1α expression in canine lymphoma using cell lines and clinical samples and found that these cells expressed HIF-1α. Moreover, the HIF-1α inhibitors, echinomycin, YC-1 and 2-methoxyestradiol, suppressed the proliferation of canine lymphoma cell lines. In a xenograft model using NOD/scid mice, echinomycin treatment resulted in a dose-dependent regression of the tumor. Our results suggest that HIF-1α contributes to the proliferation and/or survival of canine lymphoma cells. Therefore, HIF-1α inhibitors may be potential agents to treat canine lymphoma.     

Relationship between blood calcium level and ST peak interval of electrocardiographic variables in peripartum Holstein cows

The association between blood calcium levels and electrocardiographic variables was compared in 137 normal parturient and 36 peripartum recumbent Holstein cows to determine whether hypocalcemia in peripartum dairy cows can be rapidly diagnosed using electrocardiograph. Inverse of STc (ST peak interval/SS interval^0.5) and blood ionized calcium or serum calcium concentrations were strongly correlated, and both correlation coefficients were 0.81 (P<0.001). The 95% prediction interval indicated that cows with STc >0.385 ± 0.001 sec are very likely to be hypocalcemic (blood ionized or serum calcium concentrations of <0.9 mmol/l or <7.5 mg/dl, respectively). These findings indicate that hypocalcemia in parturient cows can be non-invasively estimated using the STc.     

Effects of light and microsite conditions on tree size of 6-year-old Cryptomeria japonica planted in a group selection opening

We examined the extent to which direct and indirect measures of light and microsite conditions could explain variation in tree height and diameter at the base of 6-year-old Cryptomeria japonica trees planted in a group selection opening of about 0.32 ha on a steep slope at Shiiba, Miyazaki Prefecture, southern Japan. We first used the gap light index (GLI) and soil thickness (ST) as directly measured indices. For an indirect measure of light, we used a between-cohort competition index (BCI) estimated from the position and total height of residual trees. For indirect measures of microsite, we examined topographic indices (slope, plan and profile curvature, average slope gradient, and relative elevation) derived from digital elevation models (DEMs) with different resolutions ranging from 2 to 10 m. The multiple linear regression using GLI and ST explained about 45% of variation in tree size, while simple regression using only GLI explained about 35%. The contribution of ST was about half of GLI. The multiple regressions using BCI and the topographic indices did not explain any more variation than using BCI alone (R ² of about 0.26). We conclude that microsite conditions with shallower soil and steeper slope have negative effects on tree growth in group selection openings, although the relative importance is smaller than light conditions. More comprehensive studies considering several openings with more heterogeneous topography including different species are needed to generalize our growth prediction using the indirect measures, which are useful for practical forest management.     

Long-term growth analyses of Japanese cedar trees in a plantation: neighborhood competition and persistence of initial growth deviations

The individual growth of tree diameter at breast height (dbh) is analyzed in an even-aged plantation of Cryptomeria japonica from stand age of 45 to 94 years, to examine how the growth of individual trees has been affected by the changes in spacing resulting from thinning operations. At any age, a significant proportion (0.37–0.46) of the variation in dbh growth during a 5–11-year period was explained by dbh at the beginning of the period, probably due to greater leaf mass of larger trees. Next, either one-sided or two-sided competition was added to the model, by calculating the basal area (BA) of neighboring trees around each tree within a given radius or BA for trees having larger dbh than the focal tree within the radius. After preliminary analyses, a radius of 8 m was selected as the critical range for tree competition. Although both types of competition explained a significant proportion (0.09–0.43) of growth variation, one-sided competition was not significant at ages greater than 54 years. Based on the model at 45 years of age, the initial deviation of growth rate for each tree from the predicted rate was calculated and added to the models as a third variable. This raised the coefficient of determination up to 0.50–0.74. These findings have practical significance for forest plantation management, particularly for controlling the growth of standing trees via thinning, to produce high-quality timber in the future.