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Abstract: The polysaccharide compositions of cell walls isolated from the laminae and midribs of chicory (cv. Grasslands Puna II) leaves were investigated. The walls, which, except for the walls of xylem tracheary elements in vascular bundles, were non-lignified, were fractionated progressively with 50mM CDTA, 50mM Na2CO3, 1M KOH, 4M KOH, 4M KOH+3.5% H3BO3, and hot water. Monosaccharide and linkage analyses of the polysaccharides in the walls and wall fractions indicated that the polysaccharides were similar to those in the non-lignified walls of other dicotyledons. However, the proportions of pectic polysaccharides were particularly high (67% of the total wall polysaccharides in the laminae). These included homogalacturonans (50% of the total wall polysaccharides in the laminae) and rhamnogalacturonan-I (RG-I). In contrast, the proportions of cellulose, xyloglucans, heteroxylans and glucomannans were particularly low. The xyloglucans were probably fucogalactoxyloglucans. The wall polysaccharides from the leaf laminae differed from those from the midribs in having higher proportions of homogalacturonans, lower proportions of non-pectic polysaccharides, and RG-I with a higher ratio of galactan to arabinan. [Copyright &y& Elsevier]

Chromium (Cr) has been reported to modulate blood biochemistry in dairy cows. However, there is a discrepancy in the literature regarding the effects of dietary Cr supplementation on various blood parameters. This meta-analysis aimed to evaluate the effects of Cr supplementation in dairy cows on blood glucose, insulin, glucagon, nonesterified fatty acid (NEFA), cortisol, and serum total protein (STP) concentrations. Following relevant literature data extraction, a 3-level meta-analytical random effect model was fitted to the data expressed as standardized mean difference (SMD) of outcome measures of control versus Cr-supplemented cows (i.e., difference in mean between control and treatment group or pooled standard deviation). The SMD can be categorized as having a small effect (0.20), a moderate effect (0.50), and a large effect (0.80). The meta-regression identified the potential sources of heterogeneity, including the body weight of cows, experimental duration/duration of Cr supplementation, blood sampling time (3 wk before parturition until 4 wk after parturition categorized as the transition period, else as the nontransition period), and form of Cr complexes. Blood glucose did not differ significantly between control and Cr-supplemented cows with an estimated SMD of μ = 0.0071 (95% confidence interval [CI]: −0.212 to 0.226). The effect of Cr supplementation on blood insulin was also nonsignificant with an SMD of μ = 0.0007 (95% CI: −0.191 to 0.193). Cows receiving Cr supplements had significantly higher levels of glucagon than controls (95% CI: 0.116 to 0.489), with an estimated SMD = 0.303. Combined transition and nontransition data suggest Cr supplementation did not affect the concentration of NEFA. However, in transition cows, Cr supplementation significantly decreased blood NEFA levels as compared with controls (95% CI: −0.522 to −0.0039), with estimated SMD = −0.263. The estimated SMD was μ = −0.1983 (95% CI: −0.734 to 0.337) for cortisol and −0.0923 (95% CI: −0.316 to 0.131) for total protein. In summary, Cr supplementation in the transition cows decreased NEFA concentration. Blood glucose, insulin, cortisol, and STP concentrations were unaffected. However, Cr supplementation increased glucagon concentration. [ABSTRACT FROM AUTHOR]

Although salt-tolerant plants can be used to combat dryland salinity, these plants contain high concentrations of salt (NaCl), which may have deleterious effects if fed to livestock. Twenty-four Merino rams (9 mo of age) with similar body weight were equally allocated to two groups and fed a normal- or high-salt diet (0.5 and 12% NaCl, respectively) for 3 mo. Rams fed the high-salt diet had lower live weight gains, higher water intake, smaller testes (466 ± 48.4 vs 604 ± 51.1 g) and reductions ( P < 0.05 ) in spermatogenesis, ejaculate volumes (0.89 ± 0.18 vs 1.24 ± 0.15 mL/ejaculate), sperm concentration (14.3 ± 2.05 vs 22.3 ± 2.33 × 10 9 sperm/mL) and DNA integrity (DNA fragmentation rate: 5.85 ± 1.09 vs 1.13 ± 0.14%) compared to controls. For in vitro fertilization, although cleavage percentage was not significantly affected, hatching rate was lower (30.8 ± 3.81 vs 52.8 ± 4.08%, P < 0.05 ) for sperm from rams on the high-salt diet. Furthermore, the 12% salt diet decreased plasma concentrations of metabolic (leptin and insulin) and sex (T, FSH and LH) hormones, but did not affect the plasma renin-angiotensin system (RAS) component (REN, Ang II, ACE and ALD). Regarding components of the testicular RAS, the 12% salt diet decreased ( P < 0.05 ) expression of REN, Ang II and AT2 mRNA, although ACE and AT1 were unaffected. Furthermore, the 12% salt diet decreased ( P < 0.05 ) mRNA expression of key genes for spermatogenesis (Hsp70, c-kit and Cyclin A), and sex hormone receptors (AR, FSHR, LHR, CYP11A1 and CYP17A1), but there were no significant effects on key enzymes (LDH, SDH, AKP and ATPase) in the testis. In conclusion, the high-salt diet reduced ram reproductive performance; we inferred that changes in testis RAS may have had an important role in these reproductive defects. [ABSTRACT FROM AUTHOR]