Association between Anti-Müllerian Hormone Concentration and Inflammation Markers in Serum during the Peripartum Period in Dairy Cows.

The relationships between changes in anti-Müllerian hormone (AMH) concentration and various traits, including milk somatic cell counts (SCC), were evaluated. Blood samples were collected from 43 Holstein cows 14 days before (D-14) and 10 (D10) and 28 days after (D28) parturition, and vaginal discharge score (VDS) and polymorphonuclear leukocyte (PMNL) percentages were assessed in endometrial samples at D28. Cows were separated into four quartiles (Q1-Q4) based on changes in AMH concentration during the peripartum period (AMH ratio: D28/D-14). Correlations between AMH ratio and each parameter were evaluated and classified into high-AMH (Q4, 1.83 ± 0.12, n = 11) and low-AMH (Q1, 0.83 ± 0.05, n = 11) groups. The AMH ratio was positively correlated with magnesium and non-esterified fatty acids levels, and the albumin/globulin ratio at D10 and D28, but negatively correlated with serum amyloid A (SAA) at D10. SAA and γ-globulin levels were significantly higher in the low-AMH group at D28. There was no significant difference in VDS, PMNL percentage, and milk SCC between the two groups. The decreasing AMH ratio from the prepartum to the postpartum period corresponds to high inflammation biomarker levels. Whether it subsequently affects the reproductive prognosis of postpartum cows needs further investigations.

Efficacy of a single blood anti-Müllerian hormone (AMH) concentration measurement for the selection of Japanese Black heifer embryo donors in herd breeding programs.

We evaluated the relationship between plasma anti-Müllerian hormone (AMH) concentrations in Japanese Black (JB) heifers at 7-10 months of age and the number of embryos recovered after superovulation treatment in selected ovum pick-up donors, concomitantly with changes in their AMH concentrations before and after parturition. Plasma AMH concentrations in heifers were positively correlated with the total number of follicles (r = 0.647, P < 0.01) and embryos (r = 0.681, P < 0.01) recovered from the animals postpartum, when selected as donor cows, but did not correlate with the total number of transferable embryos. No difference was observed between the plasma AMH concentration at the heifer period and the postpartum period. Additionally, serum AMH concentrations of heifers weakly correlated with the number of follicles and embryos recovered by virgin flush after superovulation treatment at 13-15 months of age. Therefore, a single blood AMH concentration measurement may accelerate intensive JB cattle breeding.

Efficacy of a single measurement of plasma anti-Müllerian hormone concentration for ovum pick-up donor selection of Japanese Black heifers in herd breeding programs.

In this study, we evaluated the efficiency of a single measurement of plasma anti-Müllerian hormone (AMH) concentration in heifers in determining the number of oocytes recoverable by ovum pick-up (OPU), and compared AMH concentrations among sister heifers from the same parents. For this, blood samples from 50 embryo-transfer-derived female Japanese Black (JB) heifers (mean: 8.7 age in months) were collected and plasma AMH concentration was measured. At 13-15 months of age, both the number of follicles (2-9 mm) and the number of collected oocytes after OPU were counted and compared. Results indicated that the heifers with the highest AMH concentration had the highest number of follicles in their ovaries and gave the highest number of collected oocytes with OPU, thereby indicating that a single measurement of plasma AMH concentration is informative for the selection of OPU-donor heifers in herd breeding programs. The practice of performing a single AMH measurement may accelerate the intensive breeding of JB herds.

Gas Chromatography-Mass Spectrometry for Metabolite Profiling of Japanese Black Cattle Naturally Contaminated with Zearalenone and Sterigmatocystin.

The objective of this study was to evaluate the metabolic profile of cattle fed with or without zearalenone (ZEN) and sterigmatocystin (STC)-contaminated diets using a gas chromatography-mass spectrometry metabolomics approach. Urinary samples were collected from individual animals (n = 6 per herd) from fattening female Japanese Black (JB) cattle herds (23 months old, 550-600 kg). Herd 1 had persistently high urinary ZEN and STC concentrations due to the presence of contaminated rice straw. Herd 2, the second female JB fattening herd (23 months old, 550-600 kg), received the same dietary feed as Herd 1, with non-contaminated rice straw. Urine samples were collected from Herd 1, two weeks after the contaminated rice straw was replaced with uncontaminated rice straw (Herd 1N). Identified metabolites were subjected to principal component analysis (PCA) and ANOVA. The PCA revealed that the effects on cattle metabolites depended on ZEN and STC concentrations. The contamination of cattle feed with multiple mycotoxins may alter systemic metabolic processes, including metabolites associated with ATP generation, amino acids, glycine-conjugates, organic acids, and purine bases. The results obtained from Herd 1N indicate that a two-week remedy period was not sufficient to improve the levels of urinary metabolites, suggesting that chronic contamination with mycotoxins may have long-term harmful effects on the systemic metabolism of cattle.

Three cases of idiopathic eosinophilic enteritis with chronic obstinate diarrhea in Japanese Black fattening cattle.

Eosinophilic enteritis (EOE) is a type of inflammatory bowel disease and is characterized clinically by chronic obstinate diarrhea. Three Japanese Black (JB) fattening cattle (2 males and 1 female) on different cattle farms presented with chronic episodic diarrhea without fever or dehydration. Soft reddish spherical carneous tissues (1-3 cm) were occasionally excreted within the diarrheic feces. Administration of antibiotics, antidiarrheal drugs and vermicides had no therapeutic effect, but dexamethasone improved the fecal characteristics. The symptoms persisted until the animals were slaughtered at 27-30 months of age. Histopathological examination of the intestines revealed marked eosinophilic infiltration in the lamina propria and submucosa. From these findings, we diagnosed these cattle as the first cases of EOE in JB cattle.

Measurement of sterigmatocystin concentrations in urine for monitoring the contamination of cattle feed.

This study aimed (1) at determining the levels of the fungal toxin sterigmatocystin (STC) in the feed and urine of cattle and (2) at evaluating the effects of supplementing the feed with a mycotoxin adsorbent (MA) on STC concentrations in urine. Two herds of female Japanese Black cattle were used in this study. The cattle in each herd were fed a standard ration containing rice straw from different sources and a standard concentrate; two groups of cattle from each herd (n = six per group) received the commercial MA, mixed with the concentrate or given as top-dressing, whereas a third group received no supplement and served as control. Urine and feed samples were collected at various time points throughout the experiment. STC concentrations were measured using liquid chromatography-tandem mass spectrometry (LC-TMS). STC concentrations in straw were higher in Herd 1 (range 0.15-0.24 mg/kg DM) than in Herd 2 (range <0.01-0.06 mg/kg DM). In Herd 1, STC concentrations in urine significantly declined 2 weeks after replacing the contaminated feed, whereas MA supplementation had no effect. In conclusion, mycotoxins in urine samples are useful biological markers for monitoring the systemic exposure of cattle to multiple mycotoxins, as well as evaluating the effectiveness of interventions.

Acute colic possibly caused by phytobezoar derived from napier grass in 5 Japanese black cows reared in the same farm.

For 6 years, 5 Japanese Black cows of the same herd showed anorexia, depression, and dehydration with no feces in the rectum. Biomedical examination of 3 animals showed severe hypokalemia and hypochloremia. Although the first 3 animals died or were slaughtered (causes unknown), necropsy results showed that the cow in case 4 had intestinal obstruction due to phytobezoar derived from napier grass, fed mainly to the cattle as roughage. Therefore, farmers were recommended to avoid the hard root-stem portion of napier grass as roughage. Consequently, less phytobezoar was recovered from the fifth cow, and no similar clinical case of intestinal obstruction was observed thereafter. This is the first report on intestinal obstruction caused by phytobezoars derived from napier grass.

Successful treatment of bacillary hemoglobinuria in Japanese Black cows.

Four pasture-fed Japanese Black cows showed the main clinical symptoms of severe hemoglobinuria at different periods between 2003 and 2007. Hematological analyses at the first consultation revealed severe anemia, and biochemical analyses indicated both severe hemolysis and disruption of hepatic function. Although the first 2 patients died, the hemoglobinuria and general condition of the remaining 2 cows, who were immediately initiated on large doses of antibiotics, improved within 3 days. Clostridium haemolyticum was detected by polymerase chain reaction (PCR) analysis of the blood sample of 1 of the infected cows. Anti-fascioliasis medicine is administered, and since then, no case of hemoglobinuria has been observed. The cows were diagnosed with bacillary hemoglobinuria, and they represent the first few cases in Japan.

Effects of gamma-aminobutyric acid administration on health and growth rate of group-housed Japanese black calves fed using an automatic controlled milk feeder.

The efficacy of a gamma-aminobutyric acid (GABA) preparation in improving general health condition and growth rate was evaluated in suckling Japanese Black beef calves housed together and fed using an automatic milk feeder. The GABA preparation was administered from 4 to 10 d postpartum until weaning. A significant difference in mean body weight was observed at 3 and 8 weeks after introduction of the GABA preparation. The calves in the GABA group tended to require less medication than those in the control group (3.0 d/calf for BABA; 7.6 d/calf for the control; P=0.06). The health statuses of the 2 groups may be reflected in their blood parameters. GABA may possibly have etiotropic effects in group-housed calves fed using an automatic milk feeder.

Severe hypoplasia of the omasal laminae in a Japanese Black steer with chronic bloat--a case report.

An 11-month-old Japanese Black steer with chronic bloat underwent clinical and histological analyses. During the observation period, it showed normal appetite and fecal volume but persistent chronic bloat symptoms. Compared to controls, the steer's feces contained undigested large straws. Necropsy revealed normal rumen, reticulum, and abomasum but a small omasum. The rumen, reticulum, and abomasum mucosa was normal, with well-developed ruminal papillae. However, severe hypoplasia of the omasal laminae was observed along with hypoplasia reticular groove and ruminoreticular fold. The contents of the reticulum, omasum, and abomasums comprised undigested large sized hay particles. The omasum papillae showed no pathological abnormalities. This is a rare case of a steer with chronic bloat probably caused by severe hypoplasia of the omasal laminae.