味戸 忠春

The objectives of this study were (1) to investigate the distribution of large (≥10 mm) follicle numbers during the estrous cycle and (2) to compare the timing of the estrus expression period after the ovarian examination between cows with one large follicle (1F) and two or more large follicles (2F) with functional corpus luteum (CL) at the ovarian examination in lactating Holstein dairy cows. In experiment 1, we performed 393 ovarian examinations by ultrasonography, addressed the existence of CL (≥20 mm) and large follicle numbers, and classified cows into 1F (n = 229) and 2F (n = 164) groups. The 1F appearance rates were beyond 75% each day during 3 to 12 d after estrus. However, 2F appearance rates were beyond 75% each day during 15 to 24 d after estrus. In experiment 2, we performed 302 ovarian examinations by ultrasonography and classified cows into the 1F (n = 168) and 2F (n = 134) groups. Estrus detection was performed for 24 d after the ovarian examination in each cow. In the 2F group, 75% of estrus occurred within 9 d of the ovarian examination. However, 75% of estrus occurred 10 d after the ovarian examination in 1F. Days from the ovarian examination to estrus were significantly shorter in the 2F (6.0 d; median, 7.2 ± 4.0 d; mean ± SD) than in the 1F (13 d, 12.4 ± 4.3 d) group. In conclusion, focusing on ≥10 mm follicle numbers with CL could be useful for predicting the estrus expression period.

The objectives of this study were to assess the sequential dynamics of the endometrial polymorphonuclear cells (PMN) after calving by endometrial cytology, and clarify the factors that cause prolonged endometrial inflammation in lactating dairy cows. A total of 33 lactating Holstein dairy cows were used from -4 to 8 wk relative to calving (0 wk: the calving week). Endometrial samples were obtained sequentially from 2 to 8 wk. Body condition score and backfat thickness were obtained weekly from -4 to 8 wk. Blood samples collected from -4 to 8 wk were analyzed for indicators of energy status, hepatic function, systemic inflammation, and calcium. Blood amino acids were measured at 2 wk. Daily milk production was determined between 5 and 65 d postpartum. Based on the sequential cytological analysis, the endometrial inflammation threshold was set at ≥5.0% PMN, and the median wk of PMN% lower than 5.0% was 4.5 wk in this study; therefore, we classified the cows into the early group (cows with endometrial inflammation converged within 4 wk: n = 17) and the late group (cows with endometrial inflammation converged at or after 5 wk: n = 16). There were no differences in daily milk production, energy status, hepatic function, blood calcium concentration, and systemic inflammatory response. The late group had lower body condition scores and backfat thickness during the experimental period, and a higher blood concentration of 3-methyl histidine, indicating muscle breakdown, was observed in the late group at 2 wk. Our findings indicated that the lack of body fat reservation during the peripartum period and the increased muscle breakdown after calving were risk factors for prolonged endometrial inflammation.

In Japan, the radiocesium activity concentration in milk must be less than 50 Bq/kg-fresh to meet shipping standards, and the radiocesium concentration of the diet fed to dairy cattle must be less than 500 Bq/kg-dry. After the Fukushima nuclear accident in 2011, we conducted two experiments to investigate whether Prussian blue (PB) could suppress the radiocesium (134Cs + 137Cs) activity concentration in Japanese cattle' milk. In experiment 1, four cattle were fed a diet with a radiocesium activity concentration of 175 Bq/kg-dry, with or without PB supplementation. The PB intake ranged from 0 to 3.0 g/day, and the average radiocesium intake was 3.42 kBq/day in all treatments. The radiocesium activity concentration in milk decreased from 16.4 to 8.6 Bq/kg-fresh, and the transfer coefficient of radiocesium from diet to milk (Fm) decreased from 4.77 × 10-3 to 2.61 × 10-3 with increased PB intake. In experiment 2, three cattle were fed another diet including a radiocesium activity concentration of 927 Bq/kg-dry of with or without PB supplementation. The PB intake ranged from 0 to 18.9 g/day, and the average radiocesium intake was 15.2 kBq/day in all treatments. The milk's radiocesium activity concentration decreased from 24.3 to 4.2 Bq/kg-fresh, and the Fm decreased from 1.68 × 10-3 to 0.28 × 10-3 with increased PB intake. Our results suggest that both the radiocesium activity concentration in milk and Fm can be reduced by PB, and that Fm is affected by diet. We recommend cattle should be fed absorbents such as PB to minimize the risk of milk radiocesium activity concentration exceeding 50 Bq/kg-fresh even if the diet has a radiocesium activity concentration of less than 500 Bq/kg-dry.

In this study, two commercially available oral electrolyte solutions (OES) with high sodium (CF) or with high glucose and glycine (SL), and two prototype OES were evaluated in terms of rehydration and preventing catabolism. Prototype OES based on CF were prepared by doubling the glucose amount (CFG) or by doubling both glucose and glycine (CFGG). Thirty-two diarrheic calves were randomly assigned four groups with eight calves in each group. Blood volume increased with CF and CFGG compared with that of other OES. The catabolic preventive effect was excellent in CFGG and SL. Our results suggest that both the amount of sodium, glucose, and glycine, and ratio of these factors aid dehydration and provide energy.

The objectives of this study were to evaluate the effects of intravenous acetate Ringer's solution, with or without dextrose, on diarrheic calves with either experimentally induced or spontaneous diarrhea. In the experimental model, diarrhea was induced in nine healthy calves by administering cold milk (below 4 degrees C) twice a day for 2 days. The calves were randomly assigned to the isotonic saline (ISS), acetated Ringer's (AR) or acetated Ringer's with 5% dextrose (ARD) groups, with three calves assigned to each group. The calves received 80 ml/kg of their designated solution, at a flow rate of 20 ml/kg/hr. Infusion of ISS, AR and ARD were all found to be safe and effective in increasing plasma volume. Intravenous (IV) infusion of ISS resulted in the acidification secondary to dilution, while AR and ARD infusion inhibited acidification. In addition, prevention of catabolism was observed only with IV infusion of ARD. Sixteen calves with spontaneous diarrhea were enrolled in the clinical study. The calves were randomly assigned to the AR or ARD groups, with eight calves being assigned to each group. The calves received 100 ml/kg of their designated solution, at a flow rate of 25 ml/kg/hr. Intravenous infusion of AR and ARD was found to be effective in increasing plasma volume and inhibiting acidification. Only infusion of ARD prevented catabolism, but it also led to hyperglycemia. Our results suggest that a solution containing dextrose may be beneficial for wasting diarrheic calves.

The aim of the present study was to investigate the relationships between serum amino acid profiles in normal and calves with Mycoplasma bronchopneumonia. Serum free amino acid concentrations in serum obtained from 34 calves with or without Mycoplasma bronchopneumonia were determined by high-performance liquid chromatography. The calves with Mycoplasma were characterized by significantly lower total amino acid and total essential amino acid concentrations and molar ratios of branched-chain amino acid (BCAA) to aromatic amino acid (BCAA/AAA) and BCAA to tyrosine (BTR), and by a significantly higher molar ratio of serine phosphorylation (SPR). The proposed diagnostic cutoffs for BCAA/AAA, BTR and SPR in serum based on ROC analysis for detection of catabolic states associated with Mycoplasma bronchopneumonia were set at <1.75, <2.86 and >0.85, respectively. Our results suggest that determining the profiles of amino acids, especially BTR and SPR, could provide useful diagnostic information in terms of predicting protein catabolism in Mycoplasma bronchopneumonia.

The milk-flow, imaging, and histopathological characteristics of the teat in five cows with toxic mastitis were investigated. Teats were grouped into type I (without gross and histopathological abnormality), type II (no abnormal gross findings, but with histopathological abnormality), and type III (with gross and histopathological abnormality). Normal teats from six cows served as controls. Type II and III teats had lower milk-flow, compared with the controls. Ultrasonography revealed no abnormal findings, except for irregular mucosal surface in type II teats and absence of hyperechoic line along the teat canal in type III teats. The theloscopic findings varied from normal to mucosal abnormalities in type II and III teats. Histopathology demonstrated epithelial changes, congestion, hemorrhage, edema, cellular infiltration, and elastic fiber degradation in type II and III teats, with the type III teats showing severe changes. Toxic mastitis was characterized by impaired milk-flow and various degrees of imaging and histopathological abnormality. © 2011 Elsevier Ltd.

We examined the relationship between concentrations of serum trace minerals and incidence of diseases in Japanese Black calves in 6 prefectures of the Tohoku district, north-east Japan. As our investigation areas, several major breeding areas of Japanese Black cattle were selected in each 6 prefectures, and the mortality rate and incidence of diseases around birth (from 240 days after fertilization to 30 days after birth) was investigated for all parturition (24,873). The concentrations in serum trace minerals (Fe, Zn, Cu, Se) were also determined in 179 calves of 100 days of age or younger. Areas of which serum Se concentrations were much lower than 4.0 µg/dL (lower limit of normal level) showed greater numbers of mortality caused by weak calf syndrome (WCS) and diarrhea than in the other areas, and also showed an increase in the mortality rate during the perinatal period (7.1%). The treatment cost per calf for diarrhea was expensive, and white muscle disease was recognized in 6 calves (0.7%). Serum Fe concentration was lower in area in which the calves historically showed smaller body sizes, at an average of about 25 kg birth weight, and WCS prevalence was significantly higher. These results suggest that the deficiency of Se, capable of trasplacental transfer, in the soil caused a series of deficiencies in the feed-mother cow and neonate, and consequently affected the mortality rate in the neonates. Furthermore, Fe concentration was thought to be influenced by breeding methods, Fe concentration in milk, and feeding methods (e.g. starting age of solid diet, presence of feed additives).<br>It is important to establish an effective feeding system for trace minerals that influence the calf health, noting the soil composition and feeding condition in each area.

馬酔木(Pieris japonica)には、ピエリストキシン(Pieristoxin)やグラヤノトキシン(Grayanotoxin)、アセボトキシン(Asebotoxin)、アンドロメドトキシン(Andromedotoxin)と呼ばれる配糖体が含まれ、山羊、羊および牛における中毒例がしばしば報告されている。今回、福島県下A農場で飼育中の羊および山羊が呼吸困難と突然死を呈し、剖検により胃内から馬酔木の葉が回収されたことから、馬酔木中毒と診断した。剖検所見では、肺における重度の水腫、出血が特徴的であった。牧場の敷地には、観賞用に馬酔木が植えられており、刈り取られた葉が綿山羊に与えられたためであった。

フマル酸を尿酸性化剤として,ペットに応用するため,ネコの血液pHと尿pHに及ぼす影響を調べた。フマル酸100mg/kg体重/日あるいは300mg/kg体重/日を28日間投与した。尿酸性化剤を連用して,尿pHが5.7以下に長期にわたって低下すると血液pHまで低下し,代謝性アシドーシスの誘発が懸念されるが,ネコにフマル酸を28日間投与しても,尿pHは5.9以下には低下せず,また血液pHは正常範囲に維持された。

各種動物の皮膚pHを油分・水分・pH計一体型を用いて測定したところ、ネコが7.07±0.13、イヌが7.75±0.71、ブタが7.22±0.28、子牛が8.46±0.57、未経産牛が7.58±0.61、搾乳牛が6.86±0.23であった。また、搾乳牛を用いて部位と被毛の有無について検討したところ、頸部における皮膚pHは被毛ありが7.93±0.80、被毛なしが7.05±0.56、最後肋間における皮膚pHは被毛ありが8.25±0.92、被毛なしが6.70±0.62.であった。これらのことから、動物種により皮膚pHの異なることと、牛においては発育ステージで皮膚pHが変化すること、さらに、搾乳牛では測定部位よりも被毛の有無により皮膚pHが異なることが確認された。

The effect of an intravenous (IV) infusion of Hypertonic saline solution (HSS 7.2%, 2,400 mOsmol/kg·H2O) was evaluated by serum electrolyte concentrations and osmotic pressure in the anesthetized beagles. Sixteen beagles were assigned to 3 experimental groups (2.5, 5 or 15 ml/kg of HSS IV infusion) or a control group (5 ml/kg of isotonic saline solution (ISS) IV infusion) and were monitored for 120 min after the initiation of fluid infusion. The relative plasma volume (rPV) in the 5 ml/kg and 15 ml/kg HSS groups progressively expanded to 143.1 ± 7.4% at 3 min and 156.4 ± 5.9% at 5 min after the initiation of the fluid infusion, respectively. Significant increases were not produced by ISS and 2.5 ml/kg HSS infusion. The serum sodium and chloride concentrations in the ISS group were not altered. The 5 ml/kg HSS infusion induced transient high osmotic and sodium levels, and the serum sodium concentration remained under the 160 mM/l after the completion of the HSS infusion. However, the 15 m//kg HSS infusion induced a constant high osmotic level (340.5-352.8 mOsmol/kg·H2O) and hypernatremia (161.4-174.5 mM/l) from 10 to 90 min after the initiation of the fluid infusion. The 15 ml/kg HSS infusion induced significant decreases in the partial pressure of oxygen (PaO2), reaching 63.7 ± 8.0 mmHg at 120 min after the initiation of the fluid infusion compared with an immediately before fluid infusion value. On the basis of these findings, 5 ml/kg HSS infusion can be safely administered to healthy beagles for expanding the plasma volume without inducing hypernatremia. A 5 ml/kg HSS infusion is thus recommended for the initial field resuscitation of dogs.

The effect of an intravenous (IV) infusion of hypertonic saline solution (HSS; 7.2%, 2, 400 mOsmol/kg·H2O) was evaluated by serum electrolyte concentrations and osmotic pressure in the anesthetized beagles. Sixteen beagles were assigned to 3 experimental groups (2.5, 5 or 15 ml/kg of HSS IV infusion) or a control group (5 ml/kg of isotonic saline solution (ISS) IV infusion) and were monitored for 120 min after the initiation of fluid infusion. The relative plasma volume (rPV) in the 5 ml/kg and 15 ml/kg HSS groups progressively expanded to 143.1 ± 7.4% at 3 min and 156.4 ± 5.9% at 5 min after the initiation of the fluid infusion, respectively. Significant increases were not produced by ISS and 2.5 ml/kg HSS infusion. The serum sodium and chloride concentrations in the ISS group were not altered. The 5 ml/kg HSS infusion induced transient high osmotic and sodium levels, and the serum sodium concentration remained under the 160 mM/l after the completion of the HSS infusion. However, the 15 ml/kg HSS infusion induced a constant high osmotic level (340.5-352.8 mOsmol/kg·H2O) and hypernatremia (161.4-174.5 mM/l) from 10 to 90 min after the initiation of the fluid infusion. The 15 ml/kg HSS infusion induced significant decreases in the partial pressure of oxygen (PaO2), reaching 63.7 ± 8.0 mmHg at 120 min after the initiation of the fluid infusion compared with an immediately before fluid infusion value. On the basis of these findings, 5 ml/kg HSS infusion can be safely administered to healthy beagles for expanding the plasma volume without inducing hypernatremia. A 5 ml/kg HSS infusion is thus recommended for the initial field resuscitation of dogs.

The effects of an intravenous (iv) infusion of a small volume (5 ml/kg) or large volume (15 ml/kg) of hypertonic saline solution (HSS; 7.2%, 2,400 mOsmol/kg·H₂O) and those of an iv infusion of 5 ml/kg isotonic saline solution (ISS; 300 mOsmol/kg·H₂O) on plasma volume, arterial blood pressure, serum sodium concentrations and osmotic pressure were investigated in conscious heifers. Nine heifers (3 heifers/group) were monitored for 120 min after the initiation of fluid replacement. The relative plasma volume (rPV) in the 5 ml/kg HSS and 15 ml/kg HSS progressively increased to 137.7 ± 2.4% at t=5 min and 145.2 ± 5.4% at t=15 min, respectively. The expanding plasma volume in the 5 ml/kg HSS group remained at an up to 10% higher level until 120 min, but not in the 15 ml/kg HSS group. The 5 ml/kg HSS infusion induced transit high-osmotic (305.3 ± 4.0 mOsmol/kg·H₂O) and sodium levels (155.7 ± 3.5 mM/l) at t=5 min. However, the 15 ml/kg HSS infusion induced constant high-osmotic level (321.7-336.7 mOsmol/kg·H₂O) and hypernatremia (162.8-170.0 mM/l) from t=10 min to the rest of the experiment period. In the ISS and 5 ml/kg HSS groups, no changes in PaO₂ were observed. The 15 ml/kg HSS infusion induced a significant decrease in the partial pressure of oxygen at the t=30 min compared to the t=0 min values. On the basis of these findings, a small volume (5 ml/kg) HSS infusion can be rapidly and safely administered to cattle for expanding the plasma volume without inducing hypernatremia. A 5 ml/kg HSS infusion is thus recommended for the initial field resuscitation of cattle.

Holstein bullocks were used in this study to compare the effectiveness of five commercial parenteral fluids (saline IS, Hartmann's IH, 5%-glucose 5G, Ringers IR, and 1/2 Ringer's and 2.5% glucose combination solutions RG) in correcting the disturbances associated with dehydration induced by fasting for 48 hr. These five commercial fluids (30 ml/kg) were given to bullocks with dehydration induced by fasting for 48 hr. Arterial and venous blood samples were taken before fasting, and at 0, 15, 30, 45, 60, 90, 120, 240, 360 min, and 24 hr after initiation of fluid administration. Fasting for 48 hr induced significant reductions in body weight and relative plasma volume (rPV), of approximately 7.72 and 21.93%, respectively. During the administration period, rPV showed a progressive increase from approximately 88.1% after fasting to 113.0% with no significantly differences between groups. A rapid decrease of rPV when fluid administration has been finished was observed in the 5G and RG groups. The results of the fluid administration trial showed that the 1/2 Ringer's and 2.5% glucose combination solution inhibited the acidification of the blood, produced no change in the electrolyte balance of serum, and induced a proper reabsorption rate of glucose in the renals, and was therefore considered the best choice for the rehydration of adult cattle which have had no appetite for over 2 days.

後肢のふらつき, 起立困難, 痛覚消失などの腰痿症状を示したSPF猫6頭について病理組織学的に検索した. 病変は中枢神経に主座し, 脊髄白質では髄鞘の空胞化・膨化がみられ, アストロサイト, マクロファージの反応, 二次的な軸索崩壊などをともなっていた. 病変の分布および程度は, 腰髄, 胸髄で強く, 頸髄では比較的軽度であった. 病変の強さと腰痿症状のそれとは相関していた. 大脳白質では, 脂肪顆粒細胞の囲管性集簇とアストログリオーシスが認められ, 腰痿症状を示さなかった例で強く発現していた.

1987年10月から1988年4月までの間に1道20県、201戸の農場から集めた30日齢以下の下痢子牛270頭の直腸スワブから大腸菌を分離し、K99線毛抗原、STa産生能及びO抗原群を調べた。K99線毛抗原保有大腸菌は58頭(21.5%)から分離され、さらにSTa産生能も陽性で毒素原性大腸菌(ETEC)と同定された菌株が25戸(12.4%)、33頭(12.2%)から分離された。分離ETECのO抗原群は、O8が1例、O9が14例及びO101が18例で、O9のETECが増加傾向にあると推察された。下痢発症日齢及び糞便性状とETECの検出状況をみると、ETECは5日齢以下で水様便を呈した症例から46.8%という高い率で検出された。ETECの検出率及び検出状況は諸外国の報告とほぼ同様であり、わが国においてもETECが新生子牛の下痢に強く関与していることが明らかにされた。なお、下痢子,牛58頭から分離されたK99線毛抗原保有大腸菌のうち25頭(43.1%)からSTa非産生の大腸菌が分離されたことは注目され、これらの下痢原性が示唆されたが、今後さらに検討を要する。