Growth and morphologic response of rumen methanogenic archaea and bacteria to cashew nut shell liquid and its alkylphenol components

The growth and morphology of rumen methanogenic archaea (15 strains of 10 species in 5 genera, including 7 strains newly isolated in the present study) and bacteria (14 species in 12 genera) were investigated using unsupplemented in vitro pure cultures and cultures supplemented with cashew nut shell liquid (CNSL) and its phenolic compound components, anti-methanogenic agents for ruminant animals. Growth of most of the methanogens tested was inhibited by CNSL and alkylphenols at different concentrations ranging from 1.56 to 12.5 μg/ml. Of the alkylphenols tested, anacardic acid exhibited the most potent growth inhibition. Three gram-negative bacterial species involved in propionate production were resistant to CNSL and alkylphenols (>50 μg/ml). All the methanogens and bacteria that were sensitive to CNSL and alkylphenols exhibited altered morphology; disruption of the cell surface was notable, possibly due to surfactant activity of the tested materials. Cells division was inhibited in some organisms, with cell elongation and unclear septum formation observed. These results indicate that CNSL and alkylphenols, particularly anacardic acid, inhibit both rumen bacteria and methanogens in a selective manner, which could help mitigate rumen methane generation.     

Analysis of mesh breaking loads in cotton gill nets: Possible solution to ghost fishing

ABSTRACT:   A small number of fishers in Chiba Prefecture of eastern Japan use cotton gill nets to catch Japanese spiny lobster Panulirus japonicus. To examine the advantages of cotton gill nets, we analyzed changes in mesh breaking load of a new cotton gill net used in a fishing operation. A new cotton gill net was also soaked in a seawater tank to simulate ghost fishing conditions. The average mesh breaking load of new cotton mesh was 50.3 N. This value decreased to 19.0 N after 38 days (∼912 h), and after 82 days (∼1968 h) the mesh could be easily torn (breaking load 0.07 N). Under fishing conditions, the cumulative soak time was only 744.4 h over 19 months. The average breaking load at the end of this period was 43.1 N, a strength 86% that of the presoaked mesh. The mesh breaking load of a cotton gill net continuously soaked for 744.4 h was 26.1 N, as estimated from tank experiment data. Thus, a cotton gill net maintains reasonable strength under typical use conditions, but will degrade if lost at sea.     

Age and growth of alfonsino Beryx splendens from the Kanto District, central Japan, based on growth increments on otoliths

ABSTRACT:   Age and growth of alfonsino Beryx splendens (Lowe) were studied using counts of presumed daily incremental growth rings on the transverse section of otoliths of fish collected from the Kanto District, central Japan. Microstructural growth increments were observed from the core to the outermost margin of the broadest of approximately 50 branches formed on the surface of an otolith. Of 98 otoliths examined, 46 were readable. The number of increments and fish lengths ranged from 448 (218 mm fork length [FL]) to 3701 (411 mm FL). The ages of these fish were estimated to be 1 year, 2 months and 10 years, 2 months, respectively, assuming that an increment was formed daily. The von Bertalanffy growth equation combined for males and females was expressed as follows: L _t  = 542 {1 −  exp  [−0.133( t  + 2.00)]}, where L _t is fork length (mm) at yearly age t . The results of the present study were compared with those of other researchers who had studied alfonsino from central Japan.     

Seasonal change and distribution of grass nutritive values and minerals in an open pasture surrounded by forest

The forage quality of pasture species is spatially heterogeneous. In this study, we evaluated the dynamics and spatial structure of forage quality and attempted to relate the observed variation to differences in light availability and soil properties. We compared grass forage quality in open grasslands with forest edge environments and established plots in open Japanese grasslands surrounded by secondary forests. We sampled Anthoxanthum odoratum L. and soil from each plot in May and September. These samples were analyzed to determine the crude protein (CP), neutral detergent fiber, and mineral concentrations. We calculated Moran’s I coefficients across discrete lag distance classes to construct autocorrelograms. The CP model showed a non-random pattern in May at a lag distance of 40 m, but a clustered pattern in September at a small scale. The mineral models produced similar clustered spatial patterns. We found no strong correlation between aboveground (plant) and belowground (soil) mineral contents. CP and some mineral element concentrations in the plants collected in September were significantly greater at the forest edge than in open grasslands. The forest edge therefore appears to be a valuable place to provide grazing animals with adequate protein and mineral intake during the later part of the growing season.     

Use of parasites as biological tags for separating stocks of the starspotted dogfish Mustelus manazo in Japan and Taiwan

ABSTRACT:   The parasite fauna of Mustelus manazo from seven localitiesin Japan and Taiwan was assessed for the feasibility of using parasitesas biological tags for the identification of different host stocks.Examination of 1038 host specimens resulted in 13 parasite speciesrecorded: one nematode, two myxosporeans, two copepods and eightcestodes. Although relatively low overall prevalence of the firstfive species at different localities showed some significant differences,the samples collected in Tokyo Bay bore the lowest similarity (19.2%).These results support previous studies, which suggested the existenceof a unique host stock in Tokyo Bay. Accordingly, combinations ofprevalence data may provide useful information on stock identification.Cestodes probably have the greatest potential for use as biologicaltags. Detailed examination of 25 specimens of M .  manazo fromAomori and Tokyo Bay disclosed eight species of intestinal cestodes.A canonical discriminant analysis based on these species separatedthe two localities clearly.     

Effects of 'Five freedoms' environmental enrichment on the welfare of calves reared indoors

We provided comfortable resting areas in pens and tools for self-grooming and suppressing aggressive behavior for environmental enrichment in Japanese black and Japanese Shorthorn calves. At the start of the experiment, the black calves ( n  = 10) were 164 days old and 138 kg in weight, and the Japanese Shorthorn calves ( n  = 10) were 176 days old and 164 kg in weight. Calves of each breed were divided into two groups (the enrichment group and the non-treatment group), and each group was housed in a 4 m × 7.2 m pen. The effect of enrichment on calf welfare was estimated on the basis of daily weight gain and behavior. The brush stimulated the grooming behavior in calves although the mean time of using the brush decreased during the experiment. The partition of the feed trough and the wooden wall in the pen decreased the agonistic behavior in Japanese Shorthorn calves ( P  < 0.01) and increased the affiliative behavior in Japanese black calves ( P  = 0.08). The cleanliness of the bedding increased sternum lying and lying with the head touching the flank or ground in Japanese black calves and decreased the standing resting behavior in both breeds ( P  < 0.05 in all the cases). However, the treatments did not have an effect on daily weight gain. We concluded that the treatments would improve the welfare of calves and function as environmental enrichments.     

Effects of feeding methods on eating frustration in stabled horses

Five feeding methods were tested in stabled horses: (i) cutting hay (hay was cut into 5 cm lengths), (ii) delaying feeding time (feeding was delayed until 1 h after the usual time), (iii) increasing the feeding frequency (hay was divided into two portions; one half was given at the normal time and the other 1 h later), (iv) increasing the feeding locations (hay was available at three locations), and (v) increasing the hay varieties (three species of hay were used). The behavioral durations in the 2 h after the experimental feedings were compared with those after usual feeding. In the cutting hay treatment, hay‐eating time decreased (P < 0.05), whereas bedding‐eating time and resting time tended to increase. In the delaying feeding time treatment, bedding investigation time increased (P < 0.01) and hay‐eating time tended to increase. In the increasing the feeding frequency treatment, hay‐eating time tended to increase. In the increasing the feeding locations treatment, bedding investigation time tended to decrease. In the increasing the hay varieties treatment, resting time tended to decrease and hay‐eating time tended to increase. It was suggested that the former two feeding methods might stimulate and the latter three feeding methods might suppress eating frustration in terms of increasing consummatory behavior (eating) and decreasing appetitive (investigating) and displacement behavior (resting).     

The assessment of the effect of presenting a companion's face picture on social isolation stress using saliva sampling in cows

The effect of presenting a companion's face picture on social isolation stress was assessed by saliva sampling in cows. Three Japanese Black test cows and another companion cow were used. At 09.00 hours, one of the test cows was housed in an experimental pen with the companion in a neighboring pen. At 11.30 hours, the test cow was socially isolated by taking the companion out the neighboring pen. At 12.00 hours, the test cow was exposed to one of four treatments until 15.00 hours; presenting a blank picture (P‐Blank), a white‐ground picture of the companion's face (P‐Com) or an unfamiliar Holstein's face (P‐Hol), or the companion in the neighboring pen and a blank picture (Com). The cows were randomly exposed to all treatments. The cows' saliva were sampled for measuring salivary cortisol and chromogranin A concentrations (Sa‐Cort, Sa‐ChA) at 11.30, 12.00, 12.30 and 14.00 hours. At 12.00 hours, Sa‐ChA was higher than that at 11.30 hours (P < 0.01). At 12.30 hours Sa‐ChA of Com and P‐Com were lower than that of P‐Blank (P = 0.09, P = 0.08). At 14.00 hours Sa‐Cort of Com was lower than that of P‐Blank (P < 0.01), but Sa‐Cort of P‐Com was higher than that of P‐Blank (P < 0.01). It is suggested that P‐Com might decrease isolation stress only a short time, but afterward induced stress in cows.     

Distribution of radioactive cesium in edible parts of cattle

After the disastrous incident of the Fukushima Daiichi Nuclear Power Station, various agricultural, livestock and fishery products have been inspected for radioactive contamination with cesium in Japan. In this study, radioactive cesium was measured in various edible parts of cattle to verify the current inspection method for cattle, in which the neck tissues are generally used as samples. Radioactive cesium concentration in the short plate, diaphragm, liver, lung, omasum, abomasum and small intestine were lower and sirloin, tenderloin, top round meat and tongue were higher than that in the neck. There was no significant difference between the other organs (heart, kidney, lumen and reticulum) and the neck. Ninety‐five percent upper tolerance limits of the relative concentration to the neck were 1.88 for sirloin, 1.74 for tenderloin, 1.87 for top round and 1.45 for tongue. These results suggest that a safety factor of 2 is recommended for the radioactivity inspection of cattle to prevent a marketing of meat with higher cesium than the legal limit. Re‐inspection should be conducted using another part of muscle, for example, top round, when suspicious levels of 50–100 Bq/kg are detected in the neck.     

Display of a peer's face picture enhances the preference for a pen in preference testing in cows

Using preference testing, we investigated the effect of a brush and a peer's face picture on the welfare of breeding beef cows. Four cows were used in experiment 1 and another four cows were used in experiment 2. An experimental barn consisted of two 3.5 square-meter pens, and a corridor measuring 1.6 m wide and 1.3 m long. During the experiment, either side of the pens were treated. In experiment 1, straw bedding was placed in a treated pen (condition B) in the first two trials, a brush was added in the treated pen (condition BB) in the next two trials, and a peer's face picture was displayed in the treated pen (condition BBF) in the last two trials. In experiment 2, condition B was applied for the first two trials, a peer's face picture was displayed in the treated pen (condition BF) in the next two trials, and condition BBF was applied for the last two trials. Each cow was housed alone from 09.00 hour to 15.00 h in the experimental barn during the six trials. The cows stayed in the treatment pen longer than in the non-treatment pen under all conditions in experiments 1 and 2. In experiment 1, the mean total time spent in the treatment pen was longer under condition BBF than under conditions B and BB. In experiment 2, the mean total time spent in the treatment pen was shorter under condition B than under conditions BF and BBF. The mean percentage of time spent ruminating was greater under condition BBF than under condition B. It is concluded that the cows preferred the peer's face picture in the isolated condition of preference testing in this study.