In order to investigate the effect of E. coli vaccination on the immune function of Holstein cows, we examined immune cell subsets in the peripheral blood and colostrum as well as antibody levels in the plasma and whey. Eleven multiparous dry cows were divided into three groups based on the frequency of vaccination: cows vaccinated three times (n = 4, vaccinated at -6, -4, and -2 weeks of due date); vaccinated once (n = 4, at -4 weeks of due date) and unvaccinated (n = 3). Blood samples were obtained 7 times at -6, -4, and -2 weeks of the due date and 3 days and 1, 2, and 3 weeks after calving. Colostrum was obtained at the first milking on the day of calving. At 3 days after calving, the number of peripheral CD4⁺T cells was significantly higher in cows vaccinated three times (1,643±316 cells/mℓ) compared to cows vaccinated once (933±339 cells/mℓ)(p<0.05). At Week 3, the number of peripheral CD4⁺T cells was significantly higher in cows vaccinated three times (1,250±230 cells/mℓ) compared to unvaccinated cows (778±29 cell/mℓ). The number of peripheral CD8⁺T cells in cows vaccinated three times was significantly higher than in the other two groups from Week -4 to Week 3. The number of peripheral γ/δ T cells in cows vaccinated three times (303±100 cells/mℓ)was significantly lower than in that in cows vaccinated once (573±145 cells/mℓ) at Week 2. Plasma IgG1 in cows vaccinated once (7.4±1.6mg/mℓ) was significantly lower than in unvaccinated cows (10.7±3.6mg/mℓ) at Week 1. IgA in colostrum was higher in cows vaccinated once (11.4±1.6mg/mℓ, p<0.05) and in cows vaccinated three times (10.1±3.3mg/mℓ, statistically not significant) than in unvaccinated cows (4.8±2.9mg/mℓ). These results suggest that three-time vaccination for E. coli enhanced peripheral cellular immunity and that both single and three-time vaccination regimens enhanced humoral immunity in the mammary gland. E. coli vaccination during the dry period may be useful for protection against infection in the mammary gland and thus in colostrum-fed calves.

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The aim of the present study was to examine the effect of nutrition on the pregnancy rate in Japanese Black cows. The experiments were carried out during two periods. In Period I, 61 dry cows were self-fed roughage, which was composed of two types of silage and hay, and adjusted to have a TDN sufficiency ratio of over 130% and a DMI sufficiency ratio of over 100%. In Period II, 29 dry cows were used, and according to the result of MPT in Period I, shelled corn was added to the roughage to yield a TDN sufficiency ratio of over 120 %, a DCP sufficiency ratio of less than 200 % and a DMI sufficiency ratio of over 100% . In both periods, feeds were analyzed for composition at every harvest and mixed using a TMR mixer. The amount of feed was adjusted to satisfy the requirements so that the body weight could be maintained from two months before embryo transfer (ET). Fresh and frozen embryos were used for ET. MPT was conducted on randomly selected cows one month after ET. The mean TDN sufficiency ratios were significantly different between PeriodsⅠandⅡ (p<0.01; 137% vs. 113 %). The mean DCP sufficiency ratios were also significantly different between PeriodsⅠandⅡ(p<0.01; 310% vs. 147%), as the protein content was reduced in PeriodⅡ. The DMI sufficiency ratios in Periods I and II were 106 and 114%, respectively. The mean NFC concentration was significantly different between PeriodsⅠandⅡ (p<0.01; 7.9% vs. 17.6%). Serum FFA, BHB and UN were significantly different between PeriodsⅠandⅡ (BHB: 419.6 vs. 296.1μmol/ℓ, p<0.01; BUN: 14.6 vs. 10.3 mg/dℓ, p<0.01; FFA: 68.2 vs. 43.0μEq/ℓ, p<0.05). These results indicate that the feed in Period I contained little NFC and a high level of DCP and therefore these cows had insufficient energy due to poor fermentation in the rumen. The total pregnancy rates after ET were significantly different between Periods ⅠandⅡ [p<0.05; 37.7% (23/61) vs. 65.5% (19/29)]. These results suggest that MPT was effective for feeding management to improve the pregnancy rate, and the pregnancy rates was negatively affected by imbalance of NFC and DCP, or excessive intake of DCP, in Japanese Black cows. In addition, it was found that feeding of too much forage grasses could cause excessive intake of CP.

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The objective of this study was to define the clinical characteristics that could be used to differentiate urethral obstruction and bladder rupture caused by urolithiasis in beef steers and to reveal the differences in blood profiles in recovered and dead animals. Eighteen steers, which underwent ureterostomy for urethral obstruction, and 20 clinically healthy beef steers (controls) were used. The former steers were divided into two groups, one with urethral obstruction (n=8) and the other with bladder rupture (n=10), based on lower abdominal ultrasonography and cystoscopy. In cases with bladder rupture, the therapy consisted of indwelling bladder catheter, drainage of ascites, intraperitoneal administration of physiological saline solution with antibiotics (ampicillin and cloxacillin, 2g each), fluid infusion of acetate Ringer's solution (5-10ℓ/day) and other necessary treatments. In these steers, the clinical signs such as anorexia, anuria, hypokinesia of the rumen and diarrhea were seen in all cases, and the bladders were strained or slackened on rectal examination. In the urethral obstruction group, plasma total protein (TP) and total bilirubin (T-Bil) were significantly higher, and plasma inorganic phosphate (iP) was significantly lower than those in the control group. In the bladder rupture group, the red blood cell count, hematocrit, plasma TP, glucose, T-Bil, urea nitrogen (UN) and creatinine (Crea) were significantly higher and plasma sodium (Na), chloride (Cl) and plasma iP/UN ratio were significantly lower than those in the control group. Of 10 steers with bladder rupture, 5 died (50%), and blood examination results after 2 - 6 days of ureterostomy revealed significantly higher plasma UN and lower concentrations of plasma Na and Cl than those in the recovered steers. Our results suggest that when anorexia, diarrhea, anuria and absence of tenesmus [or “stranguria"] are accompanied by plasma iP/UN of < 0.15, plasma Cl of < 95 mEq/ℓ, plasma UN of > 35 mg/dℓ, plasma Crea of > 2.5 mg/dℓ, a bladder rupture should be suspected. Taking these findings together, complete blood count, plasma UN, Crea and electrolytes in addition to clinical symptoms are useful indicators for differential diagnoses of urolithiasis and prognostic prediction of bladder rupture.

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In order to improve the practical value of intraruminal radio transmission pH sensors for cattle, we developed an instrument that enabled recovery of the sensor from the proventriculus via oral route thus allowing calibration and battery exchange. The recovery instrument consisted of a stainless steel flexible tube connected to a support pipe and a wire inserted through the flexible tube. The wire had a spherical neodymium magnet at its tip. The tube was capped with resin for easier access to the rumen through the cardia and a protective rubber piece for prevention of losing the sensor during retraction. A chain was attached to the sensor for magnetic attraction. The instrument was tested in 15 Holstein dairy cows. Magnetic attraction was confirmed in all 15 cows, while recovery was successful in nine (60%) of them.

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The present case report describes the clinical characteristics and surgical repair of highly dilated, patent urachus and stenosis of the external urethral meatus in a calf. A 2-month-old female Japanese Black calf (50 kg BW) with a history of no urination from the external urethral meatus since birth was presented to Iwate University Veterinary Teaching Hospital for surgical removal of the urachal remnant. On clinical examination, the calf had a slightly arched back, and urine was seen dribbling through the naval. The abdomen was distended, and the pressure was too high to palpate the deeper abdominal region. Ultrasonographic examination of the abdominal cavity performed on dorsal recumbency revealed a saccular structure (10 cm × 6 cm) just caudal to the navel. The sac was filled with fluid and joined to the urinary bladder by a thin tubular structure. Highly expanded patent urachus was diagnosed, and surgery was performed. Consistent with the ultrasonographic observations, a saccular structure joining the urinary bladder was found and identified as an urachal remnant. The urachal remnant and urinary bladder were both filled up with fluid. When a light pressure was applied to the urinary bladder, urination was not observed through the external urethral meatus, but a thin occluding membrane covering the external urethral meatus was recognized. This membrane was perforated with forceps to open the external urethral meatus. The urine immediately flowed out. Then, the urachal remnant was removed together with the navel, and the urinary bladder was closed with Lembert-Cushing suture. After the peritoneal cavity was lavaged with sterilized saline, the surgical incision was closed. After the surgery, the calf showed spontaneous urination through the external urethral meatus. When the removed urachus was cut open, hypertrophy of the wall was observed with fluid (urine) inside. Escherichia coli was isolated by bacteriological culture.

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