Histological Characteristics of Conjunctiva-Associated Lymphoid Tissue in Young and Adult Holstein Cattle

The conjunctiva-associated lymphoid tissue (CALT) has been used as a target site for mucosal vaccinations in several animals. In this study, we compared the morphological features of CALT in the eyelid and third eyelid between Holstein calves and adult cows. In the eyelids, CALTs in the form of diffused lymphoid tissue (DLT) and lymphatic follicles (LF) were observed, where DLTs were dominant and LFs were scarce. The CALTs of cows comprised T-, B-cells, macrophages, and antigen-presenting cells (APCs). In particular, B-cells were dominant except in the eyelids of the calves. The epithelial layer covering the CALT is often discontinuous and lacks goblet cells. Cytokeratin18 is strongly expressed in the epithelial layer covering the CALT, except in the third eyelids of adult cows. IgA-positive cells were diffusely distributed in the lamina propria of the conjunctiva of the eyelids and third eyelids. The eyelid CALT area in calves was lower than that in adult cows. Furthermore, the CALT of calves had a lower cellularity of B-cells and a higher cellularity of macrophages than that of adult cows. These histological characteristics indicate that CALT plays a role in the mucosal immune-inductive and effector sites. Furthermore, lower cellularity of B-cells in the CALT of calves indicates that the function of CALT as a mucosal immune induction site is less developed in calves than in adult cows.

Preoperative protocol for right flank laparotomy affects postoperative serum cortisol concentrations in dairy cows

OBJECTIVE

To evaluate analgesic efficacy of 3 different preoperative protocols in cows undergoing right flank laparotomy for displaced abomasum.

ANIMALS

40 cows diagnosed with displaced abomasum.

PROCEDURES

The cows were assigned by block randomization to 1 of 3 preoperative protocols: inverted L-block using 50 mL of 2% lidocaine (ILB; n = 13), ILB plus preoperative flunixin meglumine (2 mg/kg, IV; ILB-F; 13), and dorsolumbar epidural anesthesia using 2% xylazine (0.8 mL) and 2% lidocaine (4 mL; EPI; 14). Venous blood samples were collected for CBC, serum biochemistry, and cortisol preoperatively and at 0 (immediately after), 3, 17, and 48 hours postoperatively.

RESULTS

The mean (95% CI) of the serum cortisol in ILB, ILB-F, and EPI were 108.7 (66.7 to 150.7), 150.7 (116.4 to 185.0), and 139.8 (93.4 to 186.3), respectively. The serum cortisol concentrations decreased over time in all groups (ILB, P = .001; ILB-F and EPI, P < .001). In the ILB group, the cortisol concentration at 17 and 48 hours postoperatively decreased (P = .026 and P = .009, respectively), compared with that preoperatively. In the ILB-F and EPI groups, the preoperative cortisol concentration was the highest and then decreased at 0, 3, 17, and 48 hours postoperatively (ILB-F, 0 hours [P = .001] and 3, 17, and 48 hours [P < .001]; EPI, all [P < .001]).

CLINICAL RELEVANCE

ILB-F and EPI improved intraoperative and immediate postoperative indicators of pain-related stress when compared to standard ILB. EPI requires less anesthetic, which may be beneficial when in short supply.

Antibody response to 1.0 and 0.5 mL doses of an inactivated bacterial vaccine against bovine respiratory disease in young Holstein calves: a field trial

Introduction

Early vaccination of cattle with an inactivated commercial bacterial vaccine against bovine respiratory disease has been reported to increase antibody production and can alleviate the disease. However, its dosage has been little investigated in young Holstein calves. This study addresses the need to establish guide values for vaccine dosage in these animals.

Material and Methods

Healthy calves received an inactivated vaccine for Histophilus somni, Pasteurella multocida and Mannheimia haemolytica intramuscularly at the ages of 1 and 4 weeks. Administered vaccine doses were 1.0 mL for the primary and booster vaccinations (1.0 + 1.0 group), 0.5 mL for the primary and 1.0 mL for the booster vaccination (0.5 + 1.0 group), or 0.5 mL for both vaccinations (0.5 + 0.5 group).

Results

Differences in the vaccine responses between the 1.0 + 1.0 group and 0.5 + 1.0 group were minor. However, the number of calves with a positive vaccine response to H. somni in the 0.5 + 0.5 group was less than half of that in the 1.0 + 1.0 and 0.5 + 1.0 groups. In logistic regression analysis, although the booster vaccination dose was positively correlated with seropositivity for H. somni, the primary vaccination dose was not correlated with vaccine response. The number of calves with positive vaccine responses to M. haemolytica was low even after booster vaccination regardless of the dose.

Conclusion

The dose of 0.5 mL can be used for primary vaccinations in newborn Holstein calves, but 1.0 mL may be required for booster vaccinations.

mRNA expression of immune factors by milk somatic cells from healthy Holstein lactating cows

This study investigated the mRNA of immune factors expressed by milk somatic cells from 72 healthy lactating Holstein cows on 1 farm. Milk samples were collected aseptically from the right front mammary gland before milking. The milk samples that had a negative reaction to the California mastitis test were used to analyze the mRNA of immune factors. Cows were divided into 2 groups based on the detection of bacteria in milk samples: positive group (n = 22 cows), which showed bacteria in cultures, and negative group (n = 50 cows), which did not show bacteria in cultures. There were significant positive correlations among the relative mRNA levels of interleukin (IL)-6, IL-8, arginase 1, chemokine (C-C motif) ligand (CCL) 1, and chemokine (C-X-C motif) ligand (CXCL) 13, as well as among the relative mRNA levels of IL-10, pentraxin 3, CCL5, and CCL14. Significantly high levels of IL-1β, IL-6, IL-8, arginase 1, Batf, CCL1, CXCL14, and toll-like receptor 4 in the positive group were discovered compared to the negative group. These results suggest that the presence of bacteria in lactating healthy dairy cows may affect mRNA levels of inflammatory mediators expressed by somatic cells.

Effect of supplementation with Saccharomyces boulardii CNCM I-1079 on vaccine response to an inactivated bacterial vaccine in young Japanese Black calves: A field trial

Saccharomyces boulardii group (SB group) calves were fed 2.0 × 1010 CFU/day of S. boulardii in milk replacer after 2 wk of age. All calves received inactivated vaccine for Histophilus somni, Pasteurella multocida, and Mannheimia haemolytica at 3 wk of age and 3 wk later. After vaccination, the SB group calves showed significantly higher (mean difference: 1.56-fold) antibody titer against H. somni than the control group. The number of calves with the antibody titer above the cut-off value for M. haemolytica of the SB group was significantly higher than that of the control, and the percentage was twice as high. In addition, the mRNA transcription of IL4 and IL10 in peripheral blood mononuclear cells at the booster of the SB group was significantly higher than those of the control. In conclusion, S. boulardii may have positively affected immune responses to the inactivated multi-bacterial vaccine in young calves in the field.

Effect of live yeast Saccharomyces cerevisiae supplementation on immune factors in Japanese Black calves during the growth periods

The aim of this study was to investigate changes in expression levels of immune factors of peripheral blood mononuclear cells (PBMC) after oral supplementation of live yeast Saccharomyces cerevisiae to healthy Japanese Black (JB) calves. This study examined JB calves (N=28): 14 calves (SC Group) received 10 g/calf/day of Saccharomyces cerevisiae (SC) (Acti-Saf Sc 47), and the other calves did not receive supplement (Control Group). Blood samples were collected 9 times during experimental period (1, 2, 3, 4, 5, 6, 7, 8 and 9 months of age), and analyzed for cytokines and chemokines mRNA expression of PBMC using Real-time PCR. The level of beta Hydroxybutanoic acid (BHB) in the SC Group was significantly high at 7 and 8 months of age compared to that in the Control Group. Lymphocyte counts in the SC Group were significantly higher at 2 and 5 to 6 months of age compared to the Control Group. Significant differences were found for IL-12p40 level at 4, 7 and 9 months of age, and for IFN-γ level at 6, 7 and 8 months of age. The level of CXCR3 was significantly higher at 6 to 7 months of age by dietary SC supplementation. These results indicated that SC supplementation improved the cellular immune responses of JB calves.

BXSB/MpJ-Yaa mice develop autoimmune dacryoadenitis with the appearance of inflammatory cell marker messenger RNAs in the lacrimal fluid

BACKGROUND

Dacryoadenitis is characteristic of an autoimmune exocrinopathy, e.g. Sjögren syndrome. We pathologically examined the lacrimal glands of autoimmune-prone BXSB/MpJ-Yaa mice for the appearance of pathological signs of dacryoadenitis progression in autoimmune dacryoadenitis models, particularly focusing on messenger RNAs in the lacrimal fluid.

METHODS

The lacrimal glands of the BXSB/MpJ-Yaa and C57BL/6 mice were histopathologically analyzed in parallel with the evaluation of lacrimation and messenger RNA expression of water channels (Aqp3, Aqp4 and Aqp5). In addition, autoimmune model mice (MRL/MpJ-lpr/lpr and NZB/NZWF1) were used for evaluating cell infiltration and detecting inflammatory cell marker messenger RNAs (Cd68, Ptprc and Cd3e) in the lacrimal fluids by polymerase chain reaction-based methods.

RESULTS

B-cell predominant lymphocytic infiltrations and the destruction of acini were observed in the lacrimal glands of BXSB/MpJ-Yaa mice. There was no significant difference in the quantity of lacrimal fluid between the BXSB/MpJ-Yaa and C57BL/6 mice. In the BXSB/MpJ-Yaa mice, Aqp3 expression increased significantly with the cell infiltration score, whereas expression of Aqp4 and Aqp5 tended to decrease. Aqp3 expression increased significantly with the cell infiltration score in BXSB/MpJ-Yaa mice. Among inflammatory cell markers, Cd68 was more frequently detected in the lacrimal fluid of the BXSB/MpJ-Yaa, MRL/MpJ-lpr/lpr and NZB/NZWF1 mice than in that of the C57BL/6 mice.

CONCLUSION

BXSB/MpJ-Yaa mice clearly developed autoimmune dacryoadenitis. The altered expression of water channels in lacrimal glands might be associated with the preservation of lacrimal fluid excretion in BXSB/MpJ-Yaa mice. The detection of inflammatory cell markers in lacrimal fluid could be used as a diagnostic marker for autoimmune dacryoadenitis.