The effect of sodium butyrate supplementation on ruminal and fecal pH and serum lipopolysaccharide-binding protein after ruminal acidosis challenge in nonlactating cows

The objective of this study was to evaluate effects of sodium-butyrate supplementation on gastrointestinal function and the inflammatory response to ruminal acidosis (RA) challenge in cows. Four nonlactating cows with a rumen cannula were assigned to two treatments in a crossover design. Treatments were ruminal administration of sodium-butyrate (BUT) or control (CON). Sodium-butyrate was provided as Gustor BP70 and administered at a butyrate dose of 0.04% per kg body weight. The CON premix was made by replacing sodium-butyrate with wheat bran. Experimental periods were 28 days long with 21-day washout period separating the treatments. On Day 25 of each period, corn starch was ruminally administered at 0.7% per kg body weight as RA challenge. After RA challenge, ruminal pH was lower, and endotoxin concentration was higher for cows provided with BUT than those with CON, but the increase in fecal starch and the decrease in fecal pH were attenuated by BUT. The effect of butyrate supplementation on serum lipopolysaccharide-binding protein after RA challenge was not found. From these findings, butyrate supplementation mitigated rectal acidosis by reducing the flux of fermentable carbohydrate into the large intestine. An anti-inflammatory effect of butyrate was not observed, possibly due to lower pH and higher endotoxin concentration in the rumen.     

Growth and ontogenetic migration of greeneye Chlorophthalmus albatrossis in Tosa Bay, Pacific Coast of South-Western Japan

ABSTRACT:   Growth and ontogenetic migration of greeneye Chlorophthalmus albatrossis were studied in the area from 100–400 m depths in Tosa Bay, from April 1996 to March 1997, using samples collected by an otter trawl net with a 1.3 mm mesh cod end. In the monthly changes of the standard length (SL) composition, four year classes were recognized, although the third- and fourth-year classes were not clearly separated in all the monthly samples. Individuals of 40–50 mm SL settled on the bottom of the 150–200 m depth zone from August to February. By May and June, they grew to 75–80 mm SL modal size, and migrated to 200–300 m depth. In one year after settlement, they grew to 125–130 mm SL, and migrated to 300–350 m depth. They grew to a maximum of 160 mm SL and were not sampled in the winter three years after settlement, suggesting either migration or mortality. Seasonal changes in the gonadosomatic index for combined samples of males and females showed that greeneye did not mature in Tosa Bay. It is suggested that the planktonic larvae are transported from the spawning grounds, the location of which remains unknown.     

Systemic Mycobacteriosis in an Aborted Thoroughbred Fetus in Japan

A male Thoroughbred fetus was aborted on day 251 of pregnancy. Gross and histological examinations detected systemic granulomatous lesions in many superficial and visceral lymph nodes and organs including the liver, tonsils, lungs, thymus, spleen, right thyroid gland and gastrointestinal tract, and suppurative placentitis, pyogranulomatous amnionitis and intralesional acid-fast bacilli were also detected. An examination of the DNA base sequence of the β subunit of RNA polymerase demonstrated that Mycobacterium avium strain 104 had infected several organs. To the best of our knowledge, this is the first report of equine fetal mycobacterial infection in Japan.     

TRIPLE‐PHASE HELICAL COMPUTED TOMOGRAPHY IN DOGS WITH HEPATIC MASSES

The purpose of this study was to determine the utility of triple‐phase helical computed tomography (CT) for differentiating canine hepatic masses. Seventy dogs with hepatic masses underwent triple‐phase CT followed by surgical removal of the hepatic masses. Triple‐phase helical CT scans for each dog included precontrast, arterial phase, portal venous phase, and delayed phase studies. The removed hepatic masses were histopathologically classified as hepatocellular carcinoma (n = 47), nodular hyperplasia (n = 14), and hepatic metastatic tumors (n = 9) in dogs. Of the 47 hepatocellular carcinomas, the most common CT findings included a heterogeneous pattern with hyper‐, iso‐, and hypoenhancement in both the arterial and portal venous phases (40/47, 85.1%). Of the 14 nodular hyperplasias, the most common CT findings were a homogeneous pattern with hyper‐ and isoenhancement in both the portal venous and delayed phases (13/14, 92.9%). Of nine hepatic metastatic tumors, the most common CT findings included a homogeneous hypoenhancement pattern in both the arterial and portal venous phases (8/9, 88.9%). In addition, 5 (55.6%) showed homogeneous hypoenhancement patterns in the delayed phase. Findings from our study indicated that triple‐phase CT is a useful tool for preoperative differentiation of hepatocellular carcinoma, nodular hyperplasia, and hepatic metastatic tumors in dogs.     

Ecology of Rhodococcus equi in horses and their environment on horse-breeding farms

Quantitative culture of R. equi in the feces of dams and foals, in the air of the stalls and in the soil of the paddocks was carried out on three horse-breeding farms during the foaling season. The isolation rates of R. equi from the feces of dams from the 3 farms suddenly increased to approximately 80% at the end of March, when the snow in the paddocks finished melting, and remained at that level during April and May. The mean number of R. equi and the isolation rate of R. equi from the feces of dams on the farms were investigated for 5 weeks before and 5 weeks after delivery. During the 10 weeks, there were no differences in the isolation rate or in the mean number of R. equi from the feces of dams. R. equi was first isolated from the feces of the foals born in February and the middle of March at 3-4 weeks of age, on the other hand, it was first isolated from the feces of foals born in the end of March and April at 1-2 weeks of age. The number of R. equi in the soil collected from the paddocks used by dams during the winter was approximately 10(2)-10(4) g-1 of soil during the experiment. R. equi was isolated from the air in the stalls at the end of March and the number of R. equi in the air increased particularly on dry and windy days.(ABSTRACT TRUNCATED AT 250 WORDS)     

Failure to gulp surface air induces swim bladder adenomas in Japanese medaka (Oryzias latipes)

In order to elucidate the effects of swim bladder inflation failure on swim bladder carcinogenesis, we investigated the sequential histopathological changes of swim bladders at 13, 24, 35, and 53 days post-hatch (dph) in medakas with an uninflated swim bladder, which was experimentally induced by denying access to the air–water interface between 0 and 6 dph. The reactive oxygen species (ROS) levels were measured at 24 dph. An uninflated swim bladder was induced in 47.3% of the fish denied access to the air–water interface (the denied group). The total incidence of swim bladder adenoma was 54.1% in the denied group; however, these tumors were observed in all fish with an uninflated swim bladder. In fact, these tumors were observed from 13 dph and onwards. The TBARS levels of the juveniles showed a 2.6-fold increase in fish with an uninflated swim bladder in the denied group compared to that in the control group. It is speculated that swim bladder inflation failure has some effects on the gas gland to produce ROS, leading to DNA damage in the gas glandular epithelium, which develops into swim bladder adenomas. Consequently, it is concluded that denying access to the air-water interface between 0 and 6 dph in medaka is an easy method of inducing swim bladder tumors in a short-term period, and is a useful method for producing tumor-bearing fish.