Serum amino acid profiles in clinically normal Noma horses.

Plasma or serum amino acids are used to evaluate nutritional status and metabolic disorders. In this study, we aimed to set reference values of serum amino acid concentrations in the Noma horse, a Japanese native horse. Thirty-one horses were classified into six age groups: neonatal foal (0-4 days), foal (0.5-1 years), youth (5 years), middle age (10 years), old (15 years), and extra-old (>20 years). Horses >5 years of age were analyzed together as the adult group. In the adult horses, there were no significant differences among the serum amino acid concentrations of each age group. The foal group had higher concentrations of alanine, aspartic acid, glutamic acid, α-aminoadipic acid, and 3-methyl-histidine than the adult group. The neonatal foal group had higher serum concentrations of phenylalanine, lysine, alanine, proline, aspartic acid, glutamic acid, ß-alanine, and ß-amino-iso-butyric acid and lower tryptophan concentrations and Fischer's ratios than the adult group. The neonatal foal group had higher ß-amino-iso-butyric acid concentrations and lower tryptophan and 3-methyl-histidine concentrations than the foal group. Therefore, reference values might be set separately in neonatal foals, foals, and adult horses. The data for the serum amino acid concentrations can be used for health care through physiological and pathological evaluations in Noma horses.

Postmortem magnetic resonance imaging findings of tricuspid atresia with ventricular and atrial septal defects and subvalvular pulmonic stenosis in a Japanese native Noma horse.

The necropsy of a 2-day-old Noma horse that died of weakness showed an enlarged cardiac base and a narrow cardiac apex, suggesting cardiac malformation. The excised heart underwent imaging to investigate its luminal structure. On three-dimensional magnetic resonance imaging, the right atrium and right ventricle were discontinuous. The right atrium communicated with the left atrium and the left ventricle communicated with the right ventricle. The lumen narrowed near the pulmonary artery valve. Since the same findings were observed on gross examination, the foal was diagnosed with tricuspid atresia with ventricular and atrial septal defects, along with subvalvular pulmonic stenosis.

Relationships between the age and blood test results or body sizes in Noma horses.

The objective of this study is to analyze the relationships between the age and blood test results or body sizes in Noma horses by using the results of periodical health examination. Out of 45 hematological or physical items examined, statistically significant, but loose correlations were observed in 14 items. Red blood cell count, activities of aspartate aminotransferase, alkaline phosphatase, and creatinine kinase, concentrations of calcium and inorganic phosphorus decreased with aging. Conversely, mean corpuscular volume, mean corpuscular hemoglobin, lipase activity, γ-globulin and chloride concentrations, body height, chest circumference and cannon bone circumference increased with aging. The changes in a few items seemed unique to Noma horse. However, most age-related changes found in this study might be considered as a common trend in horse breeds rather than distinctive characteristic in Noma horse.

Effect of seasons and sex on the physical, hematological, and blood biochemical parameters of Noma horses.

This study aimed to evaluate the influence of seasons and sex on body size and hematological and biochemistry parameters of Noma horses, a native Japanese breed. Body size was larger in winter than in summer. Laboratory testing variables, including erythrocytic parameters and urea nitrogen, total cholesterol, and creatinine kinase levels, were higher in winter, while the eosinophil count was higher in summer. These seasonal differences may be related to increased energy consumption of horses due to heat stress. The higher eosinophil counts may have been related to the dermatitis observed in summer. Stallions tended to have smaller bodies compared with mares. Future studies are necessary to investigate the effect of stress in seasonal and sex-based groups.

Association between somatic cell count or morbidity of chronic subclinical mastitis and longevity in dairy herds in Eastern Hokkaido, Japan: a cross-sectional study.

An epidemiological analysis was conducted on production records in Hokkaido, Japan, to investigate the potential association between improved milk quality and longevity outcomes. The study found significant variations in herd somatic cell count levels and chronic subclinical mastitis morbidity based on geographical area and herd size. The analysis also revealed a positive correlation between herd somatic cell count and chronic subclinical mastitis morbidity. Although the hypothesis of a causal link between milk quality and longevity was examined, no such association was found. However, intensive assistance for identified high-risk areas and farms is expected to enhance overall milk quality.

Effect of 2% meloxicam injection in Holstein dairy cows on acute clinical mastitis without systemic symptoms.

This study aimed the efficacy of meloxicam (MX) in treating acute clinical mastitis (ACM) without systemic symptoms in Holstein cows by studying improvement in udder pain, changes in prostaglandin E2(PGE2) and bradykinin (BK) levels in the milk, and milk yield (MY) after healing. Forty-two cows with ACM were randomly assigned to the MX treatment group (T group; n=21) and the control group (C group; n=21). At onset of illness (day 0), the T group received a 0.5 mg/kg subcutaneous (SC) injection of MX whereas the C group received 15 mL SC of saline solution as a placebo. Udder tenderness (UT) was measured, and milk samples were collected on days 0-3. There was little change in the MY of the T group before and after healing, whereas MY in the C group was significantly lower than after healing. UT on day 3 in the T group was significantly lower than that in the C group. PGE2 levels significantly decreased from day 0 to day 3 in both groups. A significant negative correlation between PGE2 and linear score was observed on day 1 in the T group, but not in the C group. In ACM without systemic symptoms, the administration MX may be useful for restoring MY and reducing udder pain after healing.

Efficiency of immunocastration with an anti-gonadotropin-releasing hormone vaccine on cryptorchid bulls.

Cryptorchid bulls have low economic value owing to the effects of masculinization. Moreover, surgical removal of an ectopic testis is difficult in certain clinical cases. Recently, immunocastration has garnered popularity as a nonsurgical castration method in pig farming; however, the effects of immunocastration on cryptorchid bulls are yet to be yet. Herein, we investigated endocrine changes due to immunocastration in cryptorchid bulls and studied its effectiveness. This study included 13 Holstein bulls diagnosed with cryptorchidism and classified into two groups based on pubertal period: <8 months of age (pregroup) and ≥8 months of age (postgroup). Antigonadotropin-releasing hormone (GnRH) vaccine was used for immunocastration, and two vaccine doses were administered. Blood testosterone and anti-Müllerian hormone (AMH) levels were measured and analyzed for endocrine evaluation. The testosterone levels significantly decreased following the start of immunocastration in both groups, thereby confirming the efficacy of antiGnRH vaccination in cryptorchid bulls. The AMH levels significantly increased in the pregroup with two antiGnRH vaccination, suggesting a compensatory response via the neutralization of GnRH antibodies. The AMH levels did not significantly change in the postgroup, indicating the partial suppression of AMH secretion in Sertoli cells during sexual maturation and failure of Sertoli cell maturation. Thus, we successfully restrained the serum testosterone levels in cryptorchid bulls using antiGnRH vaccine. The testosterone levels are a useful indicator of the immunocastration effect on cryptorchid bulls. Hereafter, a vaccine program that can sustain the castration effect on cryptorchid bulls is necessary.

Evaluation of the health status of mammary glands and compositional changes in udder-half milk obtained from dairy goats for milk quality management.

This study evaluated the health status of the mammary glands and milk composition of dairy goats. The California mastitis test (CMT) score, somatic cell counts (SCCs), somatic cell type, electrical conductivity (EC), N-acetyl-ß-d-glucosaminidase (NAGase) activity, mastitis-causing pathogens, and milk composition in 121 udder-half milk samples from 62 crossbreed goats (1-3 years old) at 23-45 days postpartum were compared in four categories with SCCs of <200 × 103 , <300 × 103 , 301-1000 × 103 , and >1010 × 103 cells/ml. The SCC, CMT score, EC, and NAGase activity were significantly lower (p < 0.05) in udder-half milk with SCCs of <200 × 103 and <300 × 103 cells/ml than those in milk with SCCs of 301-1000 × 103 and >1010 × 103 cells/ml. The protein, lactose/ash, and solids-not-fat (SNF) in milk with an SCC of <300 × 103 cells/ml were similar to the previously reported values. The proportion of polymorphonuclear neutrophils was significantly higher (p < 0.05) in milk with SCCs of 301-1000 and >1010 × 103 cells/ml than in milk with an SCC of <300 × 103 cells/ml. Assessing mammary gland health and milk composition based on categorization of udder-half milk by SCC may be useful for milk quality control on goat farms.

Effect of oral administration of colostrum on inflammation in the udders of dairy cows suffering from mastitis.

The present study was undertaken to examine whether oral administration of colostrum to mastitic cows reduced inflammation in the udder. Fifty milliliters of a colostrum whey product was administered orally daily for 3 days to cows suffering from mastitis. Milk was collected on day 0 and 7 of colostrum administration. For Experiment 1, milk from 11 udder quarters with high somatic cell counts (SCC) in four cows was used. SCC in milk decreased significantly after colostrum administration, whereas colostrum administration increased sodium and IgA concentrations significantly compared with those before administration. In Experiment 2, cows with clinical mastitis were divided into two groups, with and without colostrum administration, whereas all cows with subclinical mastitis were administered colostrum. Antibiotics were infused into the mammary gland from the first day of colostrum administration for 2-4 days. There was no significant decrease in SCC after colostrum administration in any group. However, udder firmness in both clinical mastitis groups was reduced after administration regardless of colostrum administration. IgA concentration in both clinical mastitis groups was significantly increased after colostrum administration compared to that before administration, although there was no significant difference between them. These results suggest the possibility that oral administration of colostrum attenuates inflammation of the mammary gland. Further studies are required to examine the effect of colostrum more precisely using cows with subclinical and chronic mastitis and longer duration of colostrum administration.

The relationships between environmental parameters in livestock pen and physiological parameters of Holstein dairy cows.

There has been an increase in temperature and the incidence of extreme weather events, such as heat wave, due to global warming, which has promoted the incidence of livestock diseases. Therefore, it is important to examine the effect of changes in environmental parameters on livestock performance. The aim of this study was to examine the relationship between ambient environmental conditions in livestock pen and the physiological parameters of Holstein dairy cows. The results showed that there was a decrease in the red blood cell counts, hemoglobin concentrations, and mean corpuscular hemoglobin concentration of the cows with increasing pen temperature, wet bulb globe temperature (WBGT), and temperature humidity index (THI). Additionally, high daily variation in temperature caused a decrease in the serum albumin levels of the cows. Moreover, the lowest serum calcium, inorganic phosphorus, and magnesium concentrations were observed in November, and were negatively correlated with the 24-hr temperature, WBGT, and THI range of the pen prior to sampling. Multiple regression analysis showed a positive correlation between serum cortisol concentration and 24-hr WBGT range of the pen prior to samplings and packed cell volume. However, serum cortisol and total protein concentrations were negatively correlated. Overall, the findings of the study suggest that large variation in temperature induced stress in the cows, which could be overcome by increased water consumption and improved protein digestion and absorption by the animals, and the addition of minerals, such as calcium to the diet.

An anatomical study of the skull, the dorsal and ventral nasal conchal bullae and paranasal sinuses in normal Noma horses: Computed tomographic anatomical and morphometric findings.

Noma horses have the smallest body size among native Japanese horses and are classified as pony breeds by their size. Additionally, the Japanese horse breeds are classified into a single lineage, which includes Mongolian horses. Great intraspecific differences reportedly exist in the head shapes of domesticated horses, which have been investigated in various horse breeds. The present study aimed to evaluate the size of the nasal conchal bullae, and the paranasal sinuses of Noma horses in relation to the skull dimensions using computed tomography. Reconstructed images of the heads of five adult Noma horses were used. Skull and paranasal sinus parameters were measured and analysed in relation to each other and were compared with the data in the literature on the skulls of various horse breeds. In comparison with pony breed, Shetland ponies and donkeys had a shorter nasal length than cranial length, while Noma horses had a longer nasal length than cranial length, similar to the larger breeds. In the nasal conchal bullae, Shetland ponies showed a negative correlation between the head and bullae size, while Noma horses, similar to larger breeds, had a positive correlation. In conclusion, our findings suggest that Noma horses, despite having a body size that belongs to the pony breed, had a distinguishing ratio of the skull and paranasal sinuses similar to that of the larger breeds. Our results provide information on the physiological morphology of the head and comparative anatomy based on genetic diversity in horses.

Forestomach developmental failure in an 11-month-old Japanese Black steer with severely retarded growth and chronic ruminal tympany.

This study reports findings from the pathological examination of the forestomach of an 11-month-old Japanese Black steer with severely retarded growth (41% of expected weight) and chronic ruminal tympany. The ruminal papillae were weakly formed (0.3-0.5 cm long) and unevenly distributed. The cellulae and cristae reticuli were underdeveloped; the cristae were 0.4-0.7 cm in height and milky white. The keratinized layer in the stratified squamous epithelium was thickened. Ruminal pH was 5.25, and ruminal volatile fatty acid concentration was 11.7 mM. The steer's severely retarded growth was considered to be caused by malnutrition due to developmental and functional failure of the forestomach.

Changes in ionized calcium concentration in the blood of dairy cows with peracute coliform mastitis.

We determined the clinical signs and blood ionized calcium (iCa) levels in dairy cows with peracute coliform mastitis (PCM). The clinical scores at the onset of the disease (day 0) and on day 2 and subsequent days were significantly (P<0.01) higher than those of healthy cows. We found a positive correlation (r=0.894, P<0.01) between iCa and total calcium (TCa) concentrations in the blood of healthy cows ; however there was no correlation from day 0 to day 3 in the blood of PCM cows. Multiple regression analysis revealed that the concentration of iCa was correlated with rectal temperature, hematocrit value, platelet count, and albumin level of PCM cows at the onset of disease (r= -0.804, r=0.6576, r=0.6182, r=0.284, P<0.01, respectively). There was no correlation between the TCa concentration and these parameters for PCM cows at day 0. Low blood iCa concentration at day 0 for PCM cows was related to symptoms of septic shock involving hypothermia, activation of the blood coagulation system, and dehydration.

Effects of intramammary infusion of Bifidobacterium breve on mastitis pathogens and somatic cell response in quarters from dairy cows with chronic subclinical mastitis.

The present study assessed the effects of intramammary infusion of Bifidobacterium breve (B. breve) on mastitis-causing pathogens and on the somatic cell counts (SCC) in lactating cows with chronic subclinical mastitis. The bacteriological cure rates of 42 quarters from 42 cows infected with Staphylococcus aureus, Corynebacterium bovis, coagulase-negative staphylococci, and environmental streptococci were 18.2% (2/11), 14.3% (1/7), 58.8% (10/17), and 28.6% (2/7), respectively, on day 14 after B. breve infusion. In a second trial, B. breve was infused into 18 quarters from 18 cows with chronic subclinical mastitis from which pathogens had not been isolated; the rates of quarters showing SCC > 50 × 104 cells/ml prior to B. breve infusion that decreased to < 30 × 104 cells/ml after infusion were significantly (p < .01) increased to 61.1% (11/18) on day 14 compared to that prior to infusion (0/18). The intramammary infusion of B. breve appears to be a non-antibiotic approach for elimination of minor pathogens and decreasing SCC in quarters with chronic subclinical mastitis in dairy cows.

Cellular and soluble components decrease the viable pathogen counts in milk from dairy cows with subclinical mastitis.

The present study was undertaken to clarify the factors that reduce the viable pathogen count in milk collected from the udders of subclinical mastitic cows during preservation. Milk was centrifuged to divide somatic cells (cellular components, precipitates) and antimicrobial peptides (soluble components, supernatants without fat layer); each fraction was cultured with bacteria, and the number of viable bacteria was assessed prior to and after culture. In 28.8% of milk samples, we noted no viable bacteria immediately after collection; this value increased significantly after a 5-hr incubation of milk with cellular components but not with soluble components (48.1 and 28.8%, respectively). After culture with cellular components, the numbers of bacteria (excluding Staphylococcus aureus and Streptococcus uberis) and yeast decreased dramatically, although the differences were not statistically significant. After cultivation with soluble components, only yeasts showed a tendency toward decreased mean viability, whereas the mean bacterial counts of S. uberis and T. pyogenes tended to increase after 5-hr preservation with soluble components. These results suggest that most pathogens in high somatic cell count (SCC) milk decreased during preservation at 15 to 25°C, due to both the cellular components and antimicrobial components in the milk. Particularly, the cellular components more potently reduced bacterial counts during preservation.

Change in viable bacterial count during preservation of milk derived from dairy cows with subclinical mastitis and its relationship with antimicrobial components in milk.

The objectives of the present study were to investigate the change in the number of viable pathogens during preservation of milk obtained from cows with subclinical mastitis and the association between the decreasing ratio of viable bacteria during preservation and the somatic cell count (SCC) and the values of lingual antimicrobial peptide (LAP), lactoferrin (LF) and lactoperoxidase (LPO). After preservation of milk at room temperature for 0, 0.5, 1, 2, 3, 4 and 5 hr, the bacterial colonies in the milk were counted to determine the number of colony forming units (CFUs). Fresh skim milk was used to determine the values of LAP, LPO and LF. Bacteria were not detected in 19.4% of milk samples, and this percentage increased up to 30% after 5 hr of preservation. The number of Staphylococcus aureus and Streptococcus uberis in milk did not change significantly during the 5-hr incubation, whereas significant decreases were observed in the number of coliforms, coagulase-negative staphylococci, yeasts and Corynebacterium bovis. High SCC significantly decreased CFUs of S. aureus and yeast after preservation of milk for 4 to 5 hr. High LF concentration in milk was associated with decrease in CFU of S. aureus during 4-hr preservation. These results suggest that the viable counts of some pathogens in milk decreased during preservation at room temperature after collection, which may be attributed to the leukocytes and antimicrobial components present in milk.

Changes in acute-phase proteins and cytokines in serum and milk whey from dairy cows with naturally occurring peracute mastitis caused by Klebsiella pneumoniae and the relationship to clinical outcome.

This study was conducted to evaluate the changes in acute-phase proteins and cytokine concentrations in dairy cows with naturally occurring peracute Klebsiella pneumoniae (K. pneumoniae) mastitis and their association with the outcome of the disease. Seventeen Holstein cows with K. pneumoniae mastitis from 8 dairy farms were divided on the basis of outcome after local and systemic therapy into 2 groups comprising 8 euthanized cows and 9 that recovered. Changes in acute-phase proteins and cytokine concentrations in cows with K. pneumoniae mastitis were evaluated at the onset of the disease (day 0) and at days 3, 7 and 14 after therapy and compared with those of 13 healthy dairy cows. The concentrations of haptoglobin (Hp) and interleukin (IL)-6 in serum and α(1)-acid glycoprotein and IL-1ß in serum and whey on day 0 were significantly (P<0.05) higher in the euthanized cows than in those that recovered and the healthy cows. A correlation (r=0.90, P<0.01, n=17) was found between IL-6 and Hp concentrations in sera from recovered and euthanized cows at day 0. This indicated that serum concentrations of Hp and IL-6 at the initial examination were prognostic factors for survival, and the cutoff values were 2,020 µg/ml and 32 ng/ml, respectively. These results suggest that IL-6 and Hp concentrations are involved in the manifestation of K. pneumoniae mastitis and may be possible indicators of the prognosis of peracute K. pneumoniae mastitis.