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Four ruminally fistulated dairy cows were used to determine the flow of soluble non-ammonia N (SNAN) entering the omasal canal. Treatments in a 4×4 Latin square with 2×2 factorial arrangement were grass silage (GS) alone, or silage supplemented with barley (GB; 6.0 kg per day on dry matter (DM) basis), rapeseed meal (GR; 2.1 kg per day), or barley (6.0 kg per day) and rapeseed meal (2.1 kg per day) (GBR). Digesta was collected from the omasal canal at 1.5 h intervals, sequentially centrifuged to eliminate microbes and precipitated with trichloroacetic acid (TCA) followed by centrifugation. A sub-sample of digesta pooled across sampling intervals was subjected to analysis using ninhydrin assay (NHA), Kjeldahl procedure (KP) and amino acid (AA) analyser to determine SNAN. Different N fractions within omasal digesta (OD) were assessed according to NHA as (i) free AA in the supernatant, (ii) peptide in the supernatant hydrolysed with 6 M HCl minus the free AA and (iii) protein obtained following hydrolysis of TCA precipitate. In all cases, fractions were corrected for ammonia N. Digesta collected at each 1.5 h interval was subjected to the same determinations to study the extent of diurnal variation in SNAN fractions. The microbial contribution to SNAN was estimated using 15 N as a microbial marker. Free AA fraction determined using NHA and AA analyser were well correlated (r2=0.93) as were total SNAN determined by NHA and the KP (r2=0.88). Mean SNAN concentration was 15.8, 79.5 and 30.5 mg N l−1 for free AA, peptide and protein fractions, respectively. Peptides constituted the largest proportion of SNAN suggesting that hydrolysis of peptides to AA is the most limiting step in rumen proteolysis rather than hydrolysis of soluble proteins to peptides or deamination of AA to ammonia. The microbial contribution to SNAN was on average 0.61, indicating that a large proportion of the flow of SNAN leaving the rumen is of microbial origin. Mean soluble dietary NAN (SDNAN) flow was 10.8 g N per day, accounting for proportionately between 0.05 and 0.10 of total dietary NAN (TDNAN). Variations in SNAN concentration followed a clear diurnal pattern, with a maximum at 1.0 h post-feeding, that declined until 7.0 h post-feeding. In conclusion, these results suggest that, despite a proportion of microbial contribution, SDNAN represents a significant component of the flow of SNAN leaving the rumen.

Four ruminally fistulated Finnish Ayrshire cows were used to study the effects of different protein supplements on concentration and flow of soluble non-ammonia N (SNAN)into the omasum.The treatments in a 4 × 4 Latin square design were a basal diet of grass silage and barley and the basal diet supplemented with fishmeal, soybean meal and maize gluten meal. Protein supplements significantly increased concentrations of peptide N (P=0.009)and total SNAN (P =0.03)fractions in omasal digesta.Peptide constituted the largest proportion of SNAN flow into the omasum indicating that hydrolysis of peptides to amino acids is the most limiting step in rumen proteolysis.The microbial contribution to SNAN was on an average 0.64 indicating that a large proportion of SNAN flow leaving the rumen was of microbial origin.The estimated SNAN flow per kg dry matter intake from the basal diet and protein supplemented diets indicated that approximately 49,22 and 37 g kg-1 of fishmeal,soybean meal and maize gluten meal protein, respectively, escaped from ruminal degradation as SNAN., Valkuaistäydennyksen vaikutusta lypsylehmän pötsistä virtaavan liukoisen rehuperäisen typen (N)pitoisuuteen ja määrään tutkittiin 4 × 4 latinalaisen neliön koemallin mukaisessa kokeessa. Koe-eläiminä oli neljä pötsifistelöityä lypsylehmää, jotka saivat kontrolliruokinnalla nurmisäilörehua ja ohraa siten, että syönti oli 95 % vapaasta syönnistä ja säilö rehun ja ohran suhde oli 55:45. Muilla ruokinnoilla perusrehuja korvattiin kalajauholla (6 %),soijarouheella (9 %) ja maissigluteenilla (6 %) siten, että ohran ja säilörehun suhteelliset osuudet pysyivät vakioina ja valkuaistäydennyksenä tulevan typen määrä oli samakaikilla valkuaisrehuilla. Valkuaistäydennys lisäsi pötsistä virtaavan peptidi-N:n ja liukoisen rehuperäisen N:n pitoisuuksia satakerran ruokasulassa, mutta erot valkuaisrehujen välillä olivat pieniä. Peptidi-N muodosti suurimman osan liukoisesta rehuperäisestä N:st ä osoittaen, että peptidien hydrolyysi aminohapoiksi on rajoittavin vaihe pötsin proteolyysissä. Mikrobi-N:n osuus liukoisesta rehuperäisestä N:stä oli 0,64 osoittaen, että suuri osa satakertaan virtaavasta rehuperäisestä liukoisesta N:stä oli mikrobista alkuperää. Laskelma liukoisen rehuperäisen N:n virtauksesta syötyä kuivaainekiloa kohti osoitti, että kalajauhosta n.49 g kg -1 soijarouheesta n.22 g kg -1 ja maissigluteenista n.37 g kg -1 virtasi ulos pötsistä hajoamatta liukoisessa muodossa.

WRKY transcription factors are encoded by a large gene superfamily with a broad range of roles in plants. Proteins containing a short VQ (FxxxVQxLTG) motif have been recently shown to interact with WRKY transcription factors, implying that AtVQ proteins are important in the plant defense responses in Arabidopsis, either as positive or negative cofactors of WRKY transcription factors. Thirty-nine Oryza sativa genes containing the VQ motif (OsVQs) were identified and the genome structures of OsVQ proteins were characterized through genome-wide analysis in rice. Also, phylogenetic tree analysis was performed with the VQ domain of Arabidopsis and rice. The expression patterns of these OsVQ genes in plants under several stress treatments were assessed, specifically, following infection with the bacterial pathogen Xanthomonas oryzae pv. oryzae (Xoo), treatment with abscisic acid (ABA), or exposure to drought. The cellular localization of a few OsVQ proteins was examined using rice protoplast system. Based on our results, we suggest that OsVQ proteins function as important co-regulators during the plant defense response to biotic and abiotic stresses.

We hypothesized that l-arginine and conjugated linoleic acid (CLA) would have additive effects in decreasing adiposity. Sprague Dawley rats were assigned to the following dietary groups (n = 6/group; 5 wk total): 1) control (2.55% l-alanine plus 1.5% canola oil); 2) arginine (1.25% l-arginine plus 1.5% canola oil); 3) CLA (2.55% l-alanine plus 1.5% CLA); and 4) arginine plus CLA (1.25% l-arginine plus 1.5% CLA). Supplemental amino acids were provided in drinking water and CLA was incorporated into the food pellets. Daily weight gain, food intake, arginine intake, and final body and eviscerated body weights were greater in rats fed supplemental CLA then in rats fed canola oil. The retroperitoneal adipose tissue:body weight ratio was less in rats fed supplemental CLA than in rats fed canola oil, but epididymal adipose tissue, liver, and soleus and extensor digitorum longus muscle weights were unaffected by arginine or CLA. CLA decreased epididymal adipose tissue concentrations of palmitoleic, oleic, and cis-vaccenic acid. CLA and arginine increased palmitate oxidation to CO(2) in epididymal adipose tissue in vitro relative to control rats. Glucose and palmitate incorporation into total lipids in epididymal adipose tissue was lower in rats fed supplemental arginine than in alanine-fed rats. Arginine increased plasma glycerol relative to alanine-fed rats and CLA and arginine independently decreased most serum essential amino acids and alanine, glutamate, glutamine, and ornithine. We conclude that CLA and arginine modulated adipose tissue metabolism by separate, but not additive, effects. Also, CLA and arginine may have depressed muscle protein turnover.

Based on observations that lactic acid bacteria have the ability to activate macrophages, we assessed the potential effects of eight different Lactobacillus strains treated with gastrointestinal enzymes on the production of nitric oxide and various cytokines in macrophages. RAW 264.7 murine macrophage cells were cultured with either precipitates or supernatants of Lactobacillus strains digested with pepsin followed by pancreatin. The increased production of nitric oxide and interleukin (IL)-1beta, IL-6, IL-12 and tumour necrosis factor (TNF)-alpha were observed when cultured with precipitates, and this effect was largely strain-dependent. In contrast, the exposure of RAW 264.7 cells to supernatants produced weaker or nearly undetectable effects in comparison to the effects of exposure to precipitates. The induction of nitric oxide appeared to be unaffected. These results demonstrate that nitric oxide and cytokines were effectively induced when the bacterial precipitate was treated with macrophages. The results of the present study also indicate that Lactobacillus strains treated with digestive enzymes are capable of stimulating the production of nitric oxide and cytokines in macrophages, which may modulate the gastrointestinal immune function of the host when it is given as a feed additive.

The production performance of multiparous lactating Sahiwal cows (n = 24) was evaluated according to both milking frequency and method. Selected animals were randomly divided into four groups containing six animals each under a completely randomized design. Cows in groups A & B were milked by the hand milking method three times per day, respectively. Similarly, cows in groups C & D were milked by the machine milking method two and three times per day, respectively. All animals were maintained under uniform feeding and management conditions. Dry matter intake was high in animal groups milked three times per day, and it remained unchanged between the hand and machine milking methods. Milk yield was higher (P 0.05) among the treatment groups. Collectively, the results show that milking three times per day instead of twice at 8-hour intervals can enhance milk yield in Sahiwal cows using both hand and machine milking methods.