Effect of wood kraft pulp feed on digestibility,ruminal characteristics,and milk production performance in lactating dairy cows

The effect of wood kraft pulp (KP) feed on dietary digestibility, ruminal fluid pH, rumen fermentation characteristics, and milk production performance in lactating dairy cows was examined. Four lactating dairy cows were used for the feeding experiment by the cross‐over design. The control group and KP group were set up as treatments. The control group was fed total mixed ration (TMR) (40% roughage and 60% concentrate) and the KP group was fed TMR containing 12% KP that replaced half of the rolled corn in the control diet. The dry matter intake, digestibility of the feed components, and milk yield were not significantly different between control group and KP group. The number of times that the ruminal fluid pH was below 6.1 tended to decrease in the KP group compared to the control group (p < 0.10). The acetic acid ratio in the ruminal fluid of the KP group increased compared to the control group (p < 0.05) and the propionic acid ratio in the ruminal fluid of the KP group decreased compared to the control group (p < 0.05). The acetate:propionate acid ratio was increased in the KP group compared with the control group (p < 0.05). Lipopolysaccharide levels in the ruminal fluid of the KP group tended to decrease compared to the control group (p < 0.10). Based on these results, it was indicated that the use of KP feed for lactating dairy cows induced the same rumen fermentation characteristics as those in cows given a large amount of roughage without depressing milk productivity. Therefore, KP could be a valuable feed resource substitute for grains, which would also reduce the risk for subacute rumen acidosis.     

Comparison of Ethylene Glycol and Propylene Glycol for the Vitrification of Immature Porcine Oocytes

Our aim was to optimize a cryoprotectant treatment for vitrification of immature porcine cumulus-oocyte complexes (COCs). Immature COCs were vitrified either in 35% ethylene glycol (EG), 35% propylene glycol (PG) or a combination of 17.5% EG and 17.5% PG. After warming, the COCs were in vitro matured (IVM), and surviving oocytes were in vitro fertilized (IVF) and cultured. The mean survival rate of vitrified oocytes in 35% PG (73.9%) was higher (P<0.05) than that in 35% EG (27.8%). Oocyte maturation rates did not differ among vitrified and non-vitrified control groups. Blastocyst formation in the vitrified EG group (10.8%) was higher (P<0.05) than that in the vitrified PG group (2.0%) but was lower than that in the control group (25.0%). Treatment of oocytes with 35% of each cryoprotectant without vitrification revealed a higher toxicity of PG on subsequent blastocyst development compared with EG. The combination of EG and PG resulted in 42.6% survival after vitrification. The maturation and fertilization rates of the surviving oocytes were similar in the vitrified, control and toxicity control (TC; treated with EG+PG combination without cooling) groups. Blastocyst development in the vitrified group was lower (P<0.05) than that in the control and TC groups, which in turn had similar development rates (10.7%, 18.1% and 23.3%, respectively). In conclusion, 35% PG enabled a higher oocyte survival rate after vitrification compared with 35% EG. However, PG was greatly toxic to oocytes. The combination of 17.5% EG and 17.5% PG yielded reasonable survival rates without toxic effects on embryo development.     

Development of prediction equation for methane‐related traits in beef cattle under high concentrate diets

The objective of this study was to develop a prediction equation for methane‐related traits in beef cattle and evaluate this equation using datasets with different cattle breeds and roughage rates. Enteric methane emission (CH₄, l/day) was measured using open‐circuit respiration chambers. Dry matter intake (DMI, kg/day), body weight (BW, kg), daily gain (DG, kg), total digestible nutrients (TDN, %DMI), and roughage rate (Rrate, %) were used as independent variables, and methane‐related traits—CH₄, CH₄ per DMI (CH₄/DMI, l/kg), and methane conversion factor (MCF, %)—were used as dependent variables. The best‐fit equations to predict methane‐related traits using a total of 76 records were CH₄ = –676.7 + 0.04194 × BW + 29.88 × DMI + 7.883 × TDN + 4.367 × Rrate, CH₄/DMI = –52.24 – 1.193 × 10^–3 × BW – 5.905 × DG + 1.077 × TDN + 0.5008 × Rrate, and MCF = –11.43 – 5.308 × 10^–4 × BW – 1.223 × DG + 0.2336 × TDN + 0.1157 × Rrate. The predictive ability of the developed equations differed between roughage rates but not between breeds. For CH₄, the predictive ability of the developed equations was better compared with previously reported equations in the low roughage rate dataset, but not in the high roughage rate dataset. Our results suggest that the developed equations of methane‐related traits can be applied in beef cattle fed with low roughage diets.     

IgG antibody subclass response against equine herpesvirus type 4 in horses

In this study, IgG subclass responses against equine herpesvirus type 4 (EHV-4) were examined by enzyme-linked immunosorbent assay (ELISA) using a type-specific region of EHV-4 glycoprotein G (gG). ELISA using sera collected from horses experimentally infected with EHV-4 revealed that IgGa and IgGb antibodies were detected at high level, but IgGc and IgG(T) antibody responses were detected at low level or were undetectable. The IgGa antibody response reached its peak on day 10 post-infection, and then dropped. The IgGb antibody response reached its maximum level on day 12 post-infection, and then the level was sustained during at least 28 days after infection. Forty healthy racehorses that had already been infected with EHV-4 possessed antibody against EHV-4. Although IgGa antibodies specific for EHV-4 were not detected in any horses, IgGb antibodies were detected and the levels correlated with total IgG antibodies against EHV-4 gG. The results suggest that EHV-4-specific IgGa and IgGb antibodies are induced in EHV-4-infected horses, and that IgGb antibody, but not IgGa, is long lasting.     

Hypothermic storage of porcine zygotes in serum supplemented with chlorogenic acid

The current study was conducted to investigate the effects of 100% foetal bovine serum (FBS) and 100% porcine follicular fluid (pFF) as a storage medium on the developmental competence of porcine zygotes stored at 25°C for 24 hr. Moreover, we evaluated the additive effects of chlorogenic acid (CGA) in the storage medium. When in vitro‐produced zygotes were stored at 25°C for 24 hr in tubes containing either tissue culture medium (TCM) 199 supplemented with 1 mg/ml bovine serum albumin (BSA), 100% of FBS or 100% of pFF, the rate of blastocyst formation was significantly higher in 100% of FBS than in BSA‐containing TCM 199. When the effects of CGA supplementation in 100% of FBS on the development of zygotes stored at 25°C for 24 hr was evaluated, more zygotes stored with 50 µM CGA developed to blastocysts compared with the other concentrations of CGA. When the formation date and quality of blastocysts derived from zygotes stored in 100% of FBS supplemented with 50 µM CGA were investigated, the highest ratio of blastocysts formation in the storage group appeared 1 day later than in the non‐stored control group. However, a higher proportion of blastocysts with apoptotic nuclei was observed in the stored group as compared to the non‐stored group. In conclusion, 100% of FBS is available for a short storage medium of porcine zygotes. The supplementation of 50 µM CGA into the storage medium improves the rates of blastocyst formation of zygotes after storage, but the quality of embryos from the stored zygotes remains to be improved.     

Effect of light irradiation on dynamics of vitamin A compounds in rotifers and Artemia

ABSTRACT:   The dynamics of vitamin A (VA) compounds in live food during enrichment were examined under different light conditions. Rotifers Brachionus plicatilis and Artemia nauplii ( Artemia ) were enriched with or without 10 mg VA palmitate (VAp) in 1 L of culture medium for 24 h under either bright (2000 lx), or dark (<1 lx) conditions. VAp, retinol (ROH), retinal (RAL) and retinoic acid (RA) contents were analyzed at 0 h (before enrichment) and at 3, 6, 12, 18 and 24 h after the onset of enrichment. Retinoid content in rotifers enriched in darkness was always higher than that enriched under light. VAp content showed two peaks at 3 and 18 h in rotifers enriched in darkness, but it showed one peak at 3 h in rotifers enriched under light. ROH and RA contents increased over the 24-h period in rotifers enriched in darkness, whereas they decreased 12 h onward in rotifers enriched under light. In Artemia , VAp and ROH contents were always higher than when enriched under the bright condition, but their dynamics showed a similar pattern in Artemia enriched under dark and bright conditions.     

In vitro development of OPU‐derived bovine embryos cultured either individually or in groups with the silk protein sericin and the viability of frozen‐thawed embryos after transfer

The optimization of single‐embryo culture conditions is very important, particularly in the in vitro production of bovine embryos using the ovum pick‐up (OPU) procedure. The purpose of this study was to examine the development of embryos derived from oocytes obtained by OPU that were cultured either individually or in groups in medium supplemented with or without sericin and to investigate the viability of the frozen‐thawed embryos after a direct transfer. When two‐cell‐stage embryos were cultured either individually or in groups for 7 days in CR1aa medium supplemented with or without 0.5% sericin, the rates of development to blastocysts and freezable blastocysts were significantly lower for the embryos cultured individually without sericin than for the embryos cultured in groups with or without sericin. Moreover, the rate of development to freezable blastocysts of the embryos cultured individually with sericin was significantly higher than that of the embryos cultured without sericin. When the frozen‐thawed embryos were transferred directly to recipients, the rates of pregnancy, abortion, stillbirth and normal calving in the recipients were similar among the groups, irrespective of the culture conditions and sericin supplementation. Our findings indicate that supplementation with sericin during embryo culture improves the quality of the embryos cultured individually but not the viability of the frozen‐thawed embryos after transfer to recipients.     

Fatty Acid Taste Receptor GPR120 Activation by Arachidonic Acid,Eicosapentaenoic Acid,and Docosahexaenoic Acid in Chickens

It has been reported that the supplementation of chicken diet with polyunsaturated fatty acids (PUFAs) such as arachidonic acid (AA), eicosapentaenoic acid (EPA), or docosahexaenoic acid (DHA) affects the qualities of eggs and meat. Previous studies have shown that a functional fatty acid taste receptor, G protein-coupled receptor 120 (GPR120), is broadly expressed in chicken oral and gastrointestinal tissues, and chickens have a gustatory perception of oleic acid, which is a chicken GPR120 agonist. The aim of this study was to elucidate the role of chicken GPR120 in response to PUFAs in chicken diets. Ca²⁺ imaging analyses revealed that chicken GPR120 was activated by AA, EPA, and DHA in a concentration-dependent manner. These results suggest that chickens can detect PUFAs via GPR120 in the oral and gastrointestinal tissues, implying that chickens have a gustatory perception of PUFAs.     

Urinary transforming growth factor-beta1 in feline chronic renal failure

Transforming growth factor-beta1 (TGF-beta1), an inflammatory cytokine, plays a role in tissue fibrosis, such as glomerular sclerosis and tubulointerstitial fibrosis of the kidneys. In the present study, the urinary TGF-beta1 level of cats diagnosed with chronic renal failure (CRF) was measured to investigate its relationship to the pathogenesis of feline CRF. Urinary TGF-beta1 levels (TGF-beta1/creatinine ratio) were significantly increased compared with healthy controls, whereas serum levels of TGF-beta1 were not. These results indicate that TGF-beta1 is expressed in the kidneys of CRF cats, and that it was reflected in the urinary TGF-beta1 level. Therefore, TGF-beta1 may play a role in feline CRF, and urinary TGF-beta1 could be used as a clinical marker for renal fibrosis.     

Evaluation of RNA interference in developing porcine granulosa cells using fluorescence reporter genes

Gene silencing using small interfering RNA (siRNA) may be useful for functional analyses of unidentified genes expressed during cell differentiation. The present study was performed to evaluate RNA interference (RNAi) in porcine granulosa cells stimulated with bovine FSH, by using two fluorescence reporter genes: a plasmid encoding green fluorescent protein (GFP) and a plasmid encoding red fluorescent protein (RFP). The siRNA targeting GFP mRNA sequence (GFP-siRNA) with both plasmids was introduced into cultured cells by lipofection. GFP- and RFP-expressing cells were observed under fluorescence microscopy and analyzed by flow cytometry. Strong fluorescence was observed after introduction of both plasmids into cells. The intensity of green fluorescence generated by GFP was greatly suppressed by introduction of GFP-siRNA, showing an approximate 70% decrease in the ratio of green to red fluorescence. Consequently, we concluded that gene silencing by siRNA can be used to analyze the functions of genes of interest during differentiation of porcine granulosa cells.