Effect of bovine lactoferrin feeding on lipopolysaccharide-induced metabolic and hormonal disturbances in preruminant calves

One of the biological functions of bovine lactoferrin (LF) is modulation of the host defense system, including cytokine production and immune response. The aim of the present study was to investigate the effect of oral administration of LF in calves on lipopolysaccharide (LPS)‐induced metabolic and hormonal changes in inflammatory response. Thirty Holstein calves at 4 day of age were given one of three oral doses of LF (0, 1, 3 g/day) for 10 days (?10 day to ?1 day). They were injected i.v. with LPS (50 ng/kg bodyweight) the day (day 0) after the end of LF treatment. Plasma samples were obtained on ?10, 0 day (immediately before LPS injection), and at 2, 6, 12, 24, 48, 72, and 96 h after LPS injection. Plasma tumor necrosis factor‐α concentrations at 2 h after LPS treatment were lower (P < 0.05) in LF 1 g/day‐fed claves compared with LF 0 g/day (control) calves. On day 0 there were no significant group differences in plasma LF concentration. Plasma concentration of haptoglobin in control calves was elevated by LPS injection. In LF groups, plasma haptoglobin concentrations slightly increased after LPS injection, but those levels at 6–24 h were lower (P < 0.05) than in the control group. The LF treatment inhibited (P < 0.05) the reduction of plasma ferrin concentration in calves following LPS challenge. The concentration of plasma aspartate aminotransferase in calves treated with LF was lower (P < 0.05) than in control calves at 24–96 h after LPS treatment. The concentration of plasma insulin‐like growth factor‐1 (IGF‐1) in all groups was decreased by LPS treatment, while in the LF groups the IGF‐1 level was higher (P < 0.05) than in the control group. Plasma adrenocorticotropic hormone and insulin concentrations in LF groups were lower (P < 0.05) than in control calves at 2 h after LPS injection. These data suggest that LF has a substantial anti‐inflammatory effect on the modulation of the host defense system in preruminant calves.     

Immunohistochemical evaluation of canine ovarian cysts

To clarify the immunohistochemical characteristics of canine ovarian cysts, 109 canine ovarian cysts (57 cysts of subsurface epithelial structures: SES, 26 graafian follicle cysts, 12 cystic rete ovarii and 14 cysts difficult to classify morphologically) were examined regarding their lining cells immunohistochemically using antibodies against placental alkaline phosphatase (PLAP), S100, inhibin alpha, desmin and AE1/AE3. Both cysts of SES and cystic rete ovarii had a positive immunoreaction to desmin and AE1/AE3, whereas all cysts all but graafian follicle cysts were negative for inhibin alpha. PLAP-positive immunoreaction was observed only in cysts of SES. Graafian follicle cysts had a positive immunoreaction to inhibin alpha, but were negative for PLAP, desmin and AE1/AE3. Fourteen cysts were difficult to classify morphologically because these cysts had single-squamous lining cells and lacked other morphological characteristics. However, these unclassified cysts were immunohistochemically divided into two groups, including positive and negative cysts, by the reactivity of PLAP. The PLAP-positive cysts were considered large cysts of SES. These results suggest that PLAP was a useful marker for classification of cysts of SES, although cysts originating from SES are not always positive for this antigen.     

Availability of a Microglia and Macrophage Marker,Iba-1, for Differential Diagnosis of Spontaneous Malignant Reticuloses from Astrocytomas in Rats

In rats, it is sometimes difficult to distinguish malignant reticuloses from astrocytomas in routine histopathological assessment. In the present study, four spontaneous brain neoplasms developing in the cerebrum of one Wistar Hannover rat and three Sprague-Dawley rats were immunohistochemically examined using microglia and macrophage markers. Histopathologically, these neoplasms were localized mainly in the cerebral cortex, hypothalamus or piriform lobe, and the portions showing solid growth did not show characteristic cellular arrangement but had an indistinct boundary with the surrounding brain parenchyma. Neoplastic cells had oval or pleomorphic small nuclei with abundant eosinophilic cytoplasm. Two cases showed neoplastic cell infiltration into the meninges and perivascular spaces. Silver staining showed lack of reticulin fiber production in the stroma of the neoplasms. Immunohistochemically, the neoplastic cells were strongly positive for Iba-1 and sporadically positive for CD68 in all four cases. On the basis of these results, all the neoplasms examined here could be distinguished from astrocytomas and diagnosed as malignant reticuloses. Thus, immunohistochemical demonstration of microglia/macrophage characters, such as using Iba-1, is considered to be helpful for differential diagnosis of malignant reticuloses from astrocytomas among spontaneously occurring primary brain neoplasms in rats.     

Comparison of Biological Responses in Rats Under Various Cigarette Smoke Exposure Conditions

A variety of exposure regimens of cigarette smoke have been used in animal models of lung diseases. In this study, we compared biological responses of smoke exposure in rats, using different smoke concentrations (wet total particulate matter [WTPM]), daily exposure durations, and total days of exposure. As a range-finding acute study, we first compared pulmonary responses between SD and F344 strains after a single nose-only exposure to mainstream cigarette smoke or LPS. Secondly, F344 rats were exposed to cigarette smoke for 2 or 13 weeks under the comparable daily exposure dose (WTPM concentration x daily exposure duration; according to Haber’s rule) but at a different WTPM concentration or daily exposure duration. Blood carboxylhemoglobin was increased linearly to the WTPM concentration, while urinary nicotine plus cotinine value was higher for the longer daily exposure than the corresponding shorter exposure groups. Gamma glutamyl transferase activity in bronchoalveolar lavage fluid (BALF) was increased dose dependently after 2 and 13 weeks of cigarette smoke exposure, while the neutrophil content in BALF was not increased notably. Smoke-exposed groups showed reduced body weight gain and increased relative lung and heart weights. While BALF parameters and the relative lung weights suggest pulmonary responses, histopathological examination showed epithelial lesions mainly in the upper respiratory organs (nose and larynx). Collectively, the results indicate that, under the employed study design, the equivalent daily exposure dose (exposure concentration x duration) induces equivalent pulmonary responses in rats.     

Application of cycling index and input-output environs for interpretation of nutrient flows in mixed rice-beef production systems in Japan

The objective of the present study was to apply two methods developed in ecology, the cycling index and input-output environs, to interpret nutrient flows in mixed rice-beef production systems. The cycling index (CI) was a quantitative measure of nutrient cycling. It was defined as the proportion of cycled nutrients to the total amount of nutrient flows. On the other hand, the input-output environs provide a quantitative distribution on a particular input or output. In this study, these methods were applied to the nutrient flows in the mixed rice-beef production systems in Japan. The results of CI provided information on the effects of nutrient cycling on the efficient conversion of nutrient imports to nutrient export. The results of input-output environs indicated that the indices represent indirect effects provided by the interaction between rice and beef production. In conclusion, these methods indicated new findings on nutrient utilization in the systems. The results of this study implied the further applicability of these two methods to the study of nutrient flows in mixed crop-animal production systems.     

Effect of climatic factors on urinary cortisol and peripheral blood leukocytes in lambs grazing on a semi-natural grassland in the Hokuriku District of Japan

The effects of climatic factors on stress and immune functions of grazing lambs in summer and autumn in the Hokuriku District of Japan were evaluated by determining urinary cortisol (U-COR) levels and peripheral blood leukocyte populations and comparing those with lambs kept indoors. Two groups of five lambs, consisting of those grazed on a semi-natural grassland (GRL) and those housed indoors in a domestic animal shelter (INL), were maintained at from July to October. The temperature–humidity index at each location was indicative of heat stress during summer; however, the U-COR elevation was not observed in both groups. The elevation was observed in GRL in autumn and was higher than INL in October. Climatic conditions in autumn were characterized by high humidity and a sudden drop in temperature. U-COR was positively correlated with the relative humidity. The GRL was exposed to low-nutrient conditions for a relatively long time. The CD4⁺/CD8⁺ T cell ratio in GRL decreased in October. Subsequently, the total leucocyte, including granulocytes, monocytes, and lymphocytes, sharply increased. The responses indicated an immune deficiency caused by immunosuppression because of a low nutrition caused by grazing and high-stress conditions in autumn.     

Functional and morphological changes in the hypothalamus-pituitary posterior lobe system after hypophysectomy in the dog

Acute diabetes insipidus-like symptoms have been reported as a complication after hypophysectomy in dogs. These symptoms are believed to be the consequence of deficiency of arginine vasopressin (AVP) secretion. The symptoms spontaneously resolve within 2 weeks, but the mechanism is unclear. In the present study, AVP secretion related to increases in Na+ concentration and serum osmotic pressure was measured, and immunohistochemical analysis in the paraventricular and supraoptic nuclei was performed after hypophysectomy in normal dog. In the hypertonic saline test, the plasma AVP concentration slightly increased in hypophysectomized dogs, although the increase was markedly smaller than that in normal dogs. An immunohistochemical study of the hypothalamus nucleus revealed that, AVP-positive cells tended to decrease after hypophysectomy. It suggests that excision of the posterior lobe by surgery injured the axon of magnocellular neuron in the hypothalamus. A decrease in the function and the number of AVP-producing and -secreting magnocellular neurons after hypophysectomy, suggests that the clinical improvement of postoperative diabetes insipidus-like symptoms may not be related to the recovery of AVP secretion.     

Application of the slope‐ratio growth assay technique to estimate tryptophan availability in soybean meal fed to young rats

The slope‐ratio assay for rat was used to determine whether tryptophan (Trp) availability in soybean meal (SBM) is affected by the presence of other amino acids (AAs). In a preliminary study, rats were fed graded levels of Trp‐supplemented diets to establish the Trp concentration range over which the weight gain response was linear. This range was found to be from 0.04% to 0.12% Trp. Subsequently, rats were fed basal (0.045% Trp) or Trp‐supplemented diets from three different sources: l ‐Trp alone, SBM, or l ‐Trp mixed with other AAs to reflect AA levels in the test SBM (AA‐mix). Weight gain in rats increased linearly with supplemental Trp intake (p < .05) for all Trp sources. Compared to the slope achieved with l ‐Trp alone, the estimated availability of Trp in SBM was 84.4%, while for the AA‐mix it was 93.4%. It is evident that the 6.6% reduction in l ‐Trp availability in AA‐mix is due to metabolic costs derived from excess levels of other AAs beside Trp, given that the absorption of crystalline l ‐Trp in the small intestine is 100%. In conclusion, the Trp availability of SBM was estimated to be around 90.4% (i.e., 84.4/93.4 × 100) after correcting for the effects of the other AAs in SBM.     

Comparison between immunohistochemistry and genetic clonality analysis for cellular lineage determination in feline lymphomas

Clinical application of genetic clonality analysis by PCR has been available in feline lymphoma. However, it is in under dispute whether the analysis can be applied for cellular lineage determination. To evaluate utility of the analysis for lineage determination, the results between immunohistochemistry and the genetic analysis were compared. Based on the result with immunohistochemistry, sensitivity of the primer for IgH was 89% and specificity was 75%. Sensitivity of the primer for TCRγ was 25% and specificity was 100%. Cross-lineage IgH rearrangement was found in 25% of T-cell lymphomas. The present study suggests that the genetic analysis had better be applied as not a definite but an adjunctive tool for lineage determination in feline lymphomas.     

Changes in morphological phenotypes and essential oil components in lavandin (Lavandula × intermedia Emeric ex Loisel.) transformed with wild-type strains of Agrobacterium rhizogenes

Hairy roots were induced from leaf-derived calli of lavandin (Lavandula × intermedia Emeric ex Loisel.) by infection with wild-type strains of Agrobacterium rhizogenes, A-5 (MAFF 02-10265) and A-13 (MAFF 02-10266). A-5-inoculated calli formed hairy roots more efficiently than A-13 ones. The transgenic shoots could be obtained from hairy root segments mediated by each Agrobacterium strain. However, different plant growth regulators were required for efficient adventitious shoot formation in each strain. In A-5, the most efficient adventitious shoot formation rate of 23.8% was observed in a medium with 4.4 × 10⁻⁶ M of 6-benzylaminopurine. On the other hand, a significantly higher rate of 13.2% was detected in a medium with 4.0 × 10⁻⁷ M of N-(2-chloro-4-pyridyl)-N′-phenylurea in A-13. Most of the regenerated plants showed dwarfism with closed internodes and extensive lateral branching, which were typical characteristics of ‘hairy root syndrome’. On the other hand, only nine of the 45 regenerated plants formed flower buds in early June, a delay of about one month compared with nontransgenic regenerated plants. The floral stalks and spikes of these plants were very short, resulting in a compacted form. Many regenerants showed a significantly lower productivity of essential oil than nontransgenic regenerants. Moreover, the relative percentage of the linalyl-cation-derived compounds, linalool and linalyl acetate, decreased in most of the regenerated plants. Compact plants with the ability of flower bud formation are assumed to be valuable not only for lavandin breeding, but also for clarifying the interaction between rol genes expression and essential oil production.