Effect of Carbohydrates on the Ability of Bull Sperm to Bind to Bovine Oviduct Epithelial Cells

In the present study, we investigated the effect of various carbohydrates on the ability of bovine spermatozoa to bind to the bovine oviduct epithelial cells (OECs). We also examined the fertilization competence and motility of spermatozoa that bind to OECs in the presence of carbohydrates. Frozen-thawed spermatozoa were incubated with OECs, with and without various carbohydrates. The sperms were then divided into two fractions: OEC-binding sperms (B-sperm) and non-OEC binding sperms (NB-sperm). The fertilization rate, ability to bind the zona pellucida, and membrane integrity of the spermatozoa as determined using a hypo-osmotic-swelling test (HOST) were lower in NB-sperm than in the unseparated spermatozoa (control). The motility of the B-sperm was maintained for a longer time than that of the control spermatozoa. The addition of N -acetyl- d -glucosamine (GlcNAc, 5 m m ) to the sperm-OEC mixture increased the number of B-sperm. D -mannose (5 m m ) and D -fucose (5 m m ) had no effect on the number of B-sperm. The motility of B-sperm, which bound to OECs in the presence of GlcNAc, however, was not maintained. When either OECs or the spermatozoa were treated with GlcNAc prior to sperm-OEC co-incubation, only sperm-side treatment enhanced sperm-OEC binding, but B-sperm motility was not maintained. The motility of spermatozoa incubated with GlcNAc was lower than that of controls. These results indicate that GlcNAc enhances sperm binding to OECs, probably via sperm surface modification, but does not promote increased sperm survival.     

Application of cycling index and input-output environs for interpretation of nutrient flows in mixed rice-beef production systems in Japan

The objective of the present study was to apply two methods developed in ecology, the cycling index and input-output environs, to interpret nutrient flows in mixed rice-beef production systems. The cycling index (CI) was a quantitative measure of nutrient cycling. It was defined as the proportion of cycled nutrients to the total amount of nutrient flows. On the other hand, the input-output environs provide a quantitative distribution on a particular input or output. In this study, these methods were applied to the nutrient flows in the mixed rice-beef production systems in Japan. The results of CI provided information on the effects of nutrient cycling on the efficient conversion of nutrient imports to nutrient export. The results of input-output environs indicated that the indices represent indirect effects provided by the interaction between rice and beef production. In conclusion, these methods indicated new findings on nutrient utilization in the systems. The results of this study implied the further applicability of these two methods to the study of nutrient flows in mixed crop-animal production systems.     

A Comparative Study on Egg Yolk IgY Production with Different Adjuvants and their Inhibitory Effects on Staphylococcus aureus

Objectives: Atopic dermatitis (AD) is one of the most common skin disorders in infants and children and is often aggravated by increased Staphylococcus aureus (S. aureus) colonization. An inhibitory effect of a specific egg yolk antibody (IgY) on S. aureus growth was demonstrated in this study. Furthermore, the effects of water- or oil-based adjuvants on the preparation of anti-S. aureus IgY and hen immunization were compared.Methods: Hens were immunized intramuscularly with formalin-killed S. aureus mixed with either a water-soluble polysaccharide λ-carrageenan, oil-based Freund''s complete adjuvant (FCA), or Freund''s incomplete adjuvant (FIA). Anti-S. aureus IgYs (FIA-IgY, FCA/FIA-IgY, and λCarra-IgY) were purified from the egg yolk of immunized hen eggs, and the activity of the IgY against S. aureus antigen was measured by ELISA. The proportion of each IgY that was absorbed by S. aureus was also determined. Then, the effect of purified anti-S. aureus IgY on S. aureus growth inhibition was investigated in vitro.Results: The yolk of eggs and purified FIA-IgY from the FIA group showed the highest antibody activity, followed by FCA/FIA-IgY and λCarra-IgY. The proportion of each IgY that was absorbed by S. aureus antigen was as follows: FIA-IgY (18.1%), FCA/FIA-IgY (12.9%), and λCarra-IgY (7.0%). Only FIA-IgY significantly inhibited S. aureus growth in liquid medium.Conclusion: A specific IgY that was produced using the FIA adjutant inhibited S. aureus growth. Although water-soluble λ-carrageenan showed an adjuvant effect on anti-S. aureus IgY induction in egg yolk, but did not inhibit S. aureus growth. The use of the oil adjuvant FIA was necessary in the preparation of anti-S. aureus IgY as a treatment for AD symptoms.     

In vitro ruminal fermentation and in situ ruminal degradation of tamarind kernel powder extract residue in wethers

We examined the in vitro fermentation characteristics and in situ dry matter (DM) and crude protein (CP) degradability of tamarind kernel powder extract residue (TKPER), a by‐product of polysaccharides thickener processing. Two types of TKPER (I and II), of which the CP and neutral detergent fiber organic matter basis contents (%) were 41.4 and 42.0 and 1.4 and 0.5, respectively, were compared with dry heat soybean (SB), soybean meal (SBM) and dry soybean curd residue (SBCR). The TKPERs had significantly lower in vitro gas production compared to the other products at each observation time (P < 0.05). The in vitro DM and CP digestibility (%) of TKPER I and II were 67.7 and 64.9, and 64.5 and 58.0, respectively, significantly lower than those of SB and SBM (P < 0.05). We used four wethers (55.6 ± 4.6 kg) with ruminal cannulas to investigate the in situ degradability of TKPER I, SB, SBM and SBCR. At the ruminal outflow rate of 0.05/h, the effective degradability (%) values of the DM and CP of TKPER I were 64.1 and 49.7, respectively, which were similar to those of SBM. In conclusion, TKPER had high CP and exhibited in situ degradability similar to that of SBM, suggesting that TKPER could be used as a protein source feed.     

Occurrence of toxic <Emphasis Type="Italic">Dinophysis acuminata</Emphasis> (Dinophyceae) in Uranouchi Inlet,Japan

In the Uranouchi Inlet, which has a commercial fishery of littleneck clam Ruditapes philippinarum, potentially toxigenic species of Dinophysis acuminata showed an annual occurrence except for the summer of 2000–2002. Relatively high abundances of D. acuminata were observed in April 2000 and November 2002. Some samples of D. acuminata cells, which were collected from the inlet in autumn 2002, contained pectenotoxin-2 (0.9–2.8 pg/cell) and okadaic acid (1.9–2.8 pg/cell). Cell length and hypotheca width of D. acuminata found in the Uranouchi Inlet were 33.7–45.0 and 21.0–31.6 μm, respectively. The length-width ratios ranged 1.21–1.71. Sequences of the 5.8S ribosomal RNA gene and flanking internal transcribed spacers, 1 and 2 of cells of D. acuminata from the inlet fell into a D. acuminata complex clade that included, D. acuminata-D. sacculus-D. acuta reported by others. In the inlet, occurrences of D. acuminata were detected within a broad water temperature range between 13.0 and 26.9°C, and those showing more than 25 cells/L were within 16.4–17.3°C for temperature and 27.6 and 34.1 for salinity. This is the first report that cells of Dinophysis acuminata from southern Japanese coastal waters contained okadaic acid and pectenotoxin-2.     

Effects of combinational treatment with ethephon and gibberellic acid on rice seedling growth and carbohydrate mobilization in seeds under flooded conditions

ABSTRACT

Early seedling growth, including seedling emergence and vigor, is crucial in direct seeded rice. In this study, we examined the effects of gibberellic acid (GA₃) and ethephon (ET) on the early growth of direct seeded rice, and on α-amylase activity and soluble sugar content in the seeds. Rice seeds were treated with water (control), ET, GA₃, or ET+ GA₃ and were allowed to grow for 21 days. The results showed that ET and GA₃ synergistically improved the lengths of mesocotyl, coleoptile, mesocotyl+ coleoptile, and first leaf. Moderate synergistic effects of ET and GA₃ were detected in the second and third leaves. ET+ GA₃ treatment induced higher α-amylase activities during early post-germination growth, which is consistent with the longer coleoptile, mesocotyl, mesocotyl+ coleoptile, and first leaf. In addition, ET+ GA₃ induced higher α-amylase activity in the seeds, and consequently, higher sucrose and glucose concentrations than other treatments. These results partially explain the regulatory mechanism underlying the synergistic interaction of ET and GA₃ on rice seedling growth in terms of starch and sugar metabolism in the seeds, and this knowledge is expected to facilitate the practical use of ET and GA₃ in direct seeded rice systems.     

Photosynthetic traits around budbreak in pre-existing needles of Sakhalin spruce (Picea glehnii) seedlings grown under elevated CO2 concentration assessed by chlorophyll fluorescence measurements

To assess the effects of elevated CO(2) concentration ([CO(2)]) on the photosynthetic properties around spring budbreak, we monitored the total leaf sugar and starch content, and chlorophyll fluorescence in 1-year-old needles of Sakhalin spruce (Picea glehnii Masters) seedlings in relation to the timing of budbreak, grown in a phytotron under natural daylight at two [CO(2)] levels (ambient: 360?μmol mol(-1) and elevated: 720?μmol mol(-1)). Budbreak was accelerated by elevated [CO(2)] accompanied with earlier temporal declines in the quantum yield of PSII electron transport (Φ(PSII)) and photochemical quenching (q(L)). Plants grown under elevated [CO(2)] showed pre-budbreak leaf starch content twice as high with no significant difference in Φ(PSII) from ambient-CO(2)-grown plants when compared at the same measurement [CO(2)], i.e., 360 or 720?μmol mol(-1), suggesting that the enhanced pre-budbreak leaf starch accumulation might not cause down-regulation of photosynthesis in pre-existing needles under elevated [CO(2)]. Conversely, lower excitation pressure adjusted for the efficiency of PSII photochemistry ((1?-?q(P)) F(v)'/F(m)') was observed in plants grown under elevated [CO(2)] around budbreak when compared at their growth [CO(2)] (i.e., comparing (1?-?q(P)) F(v)'/F(m)' measured at 720?μmol mol(-1) in elevated-CO(2)-grown plants with that at 360?μmol mol(-1) in ambient-CO(2)-grown plants), which suggests lower rate of photoinactivation of PSII in the elevated-CO(2)-grown plants around spring budbreak. The degree of photoinhibition, as indicated by the overnight-dark-adapted F(v)/F(m), however, showed no difference between CO(2) treatments, thereby suggesting that photoprotection during the daytime or the repair of PSII at night was sufficient to alleviate differences in the rate of photoinactivation.     

Prevalence and first genetic identification of Cryptosporidium spp. in cattle in central Viet Nam

We investigated the prevalence of Cryptosporidium infection in relation to age and clinical status in cattle in the central region of Viet Nam. A total of 266 fecal samples from diarrheic and non-diarrheic cattle were examined by the modified Ziehl-Neelsen staining method. Prevalence of Cryptosporidium parvum type infections, those of the Cryptosporidium andersoni type, and mixed infection of both types was 33.5% (89/266), 5.6% (15/266), and 3.4% (9/266), respectively. The infection rate of 44.3% (35/79) of C. parvum in calves less than 6 months old was significantly higher than that of 28.9% (54/187) in cattle greater than 6 months old (P < 0.01). Although no C. andersoni oocysts were detected in calves less than 3 months old, no significant difference was observed between the age groups in the prevalence of C. andersoni infection and mixed infection. The percentage of diarrheic and non-diarrheic cattle identified to be shedding C. parvum oocysts was 46.5% (74/159) and 14.0% (15/107), respectively (P < 0.0001). The risk of diarrhea was 1.7 times greater in C. parvum-infected calves than in their non-infected counterparts. DNA sequences of 18S rRNA genes of C. parvum type and C. andersoni type indicated that they were C. parvum bovine genotype and C. andersoni, respectively. This is the first genetic identification of C. parvum bovine genotype and C. andersoni from cattle in Viet Nam.     

Effects of nutritional status on hormone concentrations of the somatotropin axis and metabolites in plasma and colostrum of Japanese Black cows

We aimed to determine the effects of nutritional status on concentrations of somatotropic axis hormones (growth hormone (GH) and insulin‐like growth factor 1 (IGF‐1)), insulin and metabolites (glucose, total protein and nonesterified fatty acids (NEFA)) in the plasma and colostrum in late antepartum cows. Eight pregnant Japanese Black cows were randomly assigned to two experimental groups (n = 4 per group). Control cows (CON) received 100% of their nutritional requirements until parturition, whereas restricted group cows (RES) received 60% of their nutritional requirements. Blood samples were taken during the antepartum period, and blood and colostrum samples were collected on days 0, 1, and 3 after calving. Compared to the CON group, the RES group had higher concentrations of GH and NEFA in plasma, but significantly lower concentrations of glucose and insulin in plasma. The concentrations of GH in plasma after calving were significantly higher, but total plasma protein was significantly lower in RES than in CON cows. Compared to the CON group, the RES group had significantly higher concentrations of GH in colostrum, but significantly lower total concentrations of protein in colostrum. Concentrations of IGF‐1 were not different between the two groups. These findings suggest that maternal nutritional status during late gestation influences concentrations of GH and total protein in the blood and colostrum of Japanese Black cows.     

Degenerative changes of the cranial cruciate ligament harvested from dogs with cranial cruciate ligament rupture

Degenerative cranial cruciate ligament (CCL) rupture is characterized histologically by degenerating extracellular matrix (ECM) and chondroid metaplasia. Here, we describe the progression of chondroid metaplasia and the changes in the expression of ECM components in canine CCL rupture (CCLR). CCLs from 26 stifle joints with CCLR (CCLR group) and normal CCLs from 12 young beagles (control group) were examined histologically and immunohistochemically for expression of type I (COLI), type II (COLII), type III collagen (COLIII) and Sry-type HMG box 9 (SOX9). Cell density and morphology of CCLs were quantified using hematoxylin–eosin staining. The percentage of round cells was higher in the CCLR group than in controls. COLI-positive areas were seen extensively in the connecting fibers, but weakly represented in the cytoplasm of normal CCLs. In the CCLR group, there were fewer COLI-positive areas, but many COLI-positive cells. The percentages of COLII-, COLIII- and SOX9-positive cells were higher in the CCLR group than in controls. The number of spindle cells with perinuclear halo was high in the CCLR group, and most of these cells were SOX9-positive. Deposition of COLI, the main ECM component of ligaments, decreased with increased COLIII expression in degenerated CCL tissue, which shows that the deposition of the ECM is changed in CCLR. On the contrary, expression of SOX9 increased, which may contribute to the synthesis of cartilage matrix. The expression of COLII and SOX9 in ligamentocytes showed that these cells tend to differentiate into chondrocytes.