Direct and indirect effects of resilient pastures at farm scale

I farm a 550-ha property at coastal Whangarei Heads, Northland, in partnership with my wife Helen. While some land has been in family ownership since the 1850s, our farm has grown over the years through land and farm acquisitions. The farm consists of a dairy platform of 220 ha and 330 ha of dairy beef and dairy support. The farm is kikuyu dominant and summer dry with rainfall varying between 650 and 1100 mm per annum. Summer cropping, in-shed meal feeding, sowing Italian ryegrass and kikuyu mulching are all practices used with the aim of running a sustainable system. Perennial ryegrass pastures have limited persistence and are no longer a focus as more resilient pasture species and varieties are sown.

Carcass, internal organs, duodenal digesta bacteria and economics of broilers fed dry African porridge (Tetraptera tetrapluera ) pod meal

A study was conducted to ascertain the potential of African Porridge pod meal as natural feed additive to improve broiler performance. Its effect on carcass, internal organs, duodenal bacteria and economic benefits were examined. One hundred and twenty (120) 1-day old mixed sex Ross chicks were randomly allotted to 4 dietary treatments (T1 – T4) containing 0.0, 0.25, 0.5 and 0.75%dry African porridge pod meal respectively. Each treatment was replicated three times with 10 birds per replicate in a complete randomized design (CRD). Feed and water were given ad libitum for 8 weeks. Dressed percentage was significantly reduced (P<0.05) by African porridge pod meal which posted 68.96 - 71.93% as against 76.96% by the control. The cut-parts were not improved significantly. Abdominal fat deposition, bile secretion were increased and pancreas enlarged (P<0.05)by 0.50 and 0.75 levels of African porridge pod meal. Feeding of African porridge pod meal did not alter the nutritional value and pH of the meat. The spice showed antibacterial activity against salmonella and E. coli in the duodenum. The economic benefit was not improved, but the same as the control. In conclusion, in terms of carcass yield use of African porridge pod meal could not be advocated, but considering its antibacterial effect it could be used at 0.25% to modulate the gut of broilers.

Effects of Short-Term Dietary Protein Restriction on Blood Amino Acid Levels in Young Men

Pre-clinical studies show that dietary protein restriction (DPR) improves healthspan and retards many age-related diseases such as type 2 diabetes. While mouse studies have shown that restriction of certain essential amino acids is required for this response, less is known about which amino acids are affected by DPR in humans. Here, using a within-subjects diet design, we examined the effects of dietary protein restriction in the fasted state, as well as acutely after meal feeding, on blood plasma amino acid levels. While very few amino acids were affected by DPR in the fasted state, several proteinogenic AAs such as isoleucine, leucine, lysine, phenylalanine, threonine, tyrosine, and valine were lower in the meal-fed state with DPR. In addition, the non-proteinogenic AAs such as 1- and 3-methyl-histidine were also lower with meal feeding during DPR. Lastly, using in silico predictions of the most limiting essential AAs compared with human exome AA usage, we demonstrate that leucine, methionine, and threonine are potentially the most limiting essential AAs with DPR. In summary, acute meal feeding allows more accurate determination of which AAs are affected by dietary interventions, with most essential AAs lowered by DPR.

Oat Beta-Glucan and Postprandial Blood Glucose Regulation: A Systematic Review and Meta-Analysis of Acute, Single-Meal Feeding, Controlled Trials

Objectives The efficacy of oat beta-glucan (OBG), a viscous soluble fibre, on postprandial glycemic outcomes may depend on the nature of the control and the dose and molecular weight (MW) utilized. We undertook a systematic review and meta-analysis of acute clinical trials to determine whether these features mediate the glycemic response to OBG. Methods MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were searched through October 2, 2019. We included acute, single-meal feeding, controlled trials investigating the effect of OBG (concentrate or oat bran) added to a carbohydrate-containing meal compared to a comparable meal (matched control) or a different carbohydrate-containing meal (unmatched control). Two reviewers extracted the data and assessed the risk of bias. The primary outcome was incremental area under the curve (iAUC) for blood glucose. Data were pooled using the generic-inverse variance method with random effects model and expressed as ratio of means with [95% Cis]. Results We included 93 trial comparisons (N = 432). OBG reduced glucose iAUC by 23% (0.77 [0.73 to 0.81]). The effect was not significantly different between matched and unmatched controls (P = 0.17). Dose and MW were significant effect modifiers (P &lt; 0.01). OBG doses per 30 g available carbohydrate of &lt;1.5 g, 1.5 to &lt;2.5 g, 2.5 to &lt;3.5 g, 4.5 to &lt;5.5 g, and &gt;5.5 g OBG led to reductions of 9% (0.91 [0.81 to 1.02]), 14% (0.86 [0.80 to 0.93]), 17% (0.83 [0.76 to 0.90]), 31% (0.69 [0.64 to 0.74)], and 39% (0.61 [0.56 to 0.66]), respectively. Low MW OBG (&lt;300,000 g/mol) had no effect (1.00 [0.94 to 1.07]) but medium MW (300,000 to &lt;1000,000 g/mol) and high MW (&gt;1000,000 g/mol) OBG led to significant reductions of 23% (0.77 [0.69 to 0.87]) and 32% (0.68 [0.63 to 0.73]), respectively. Conclusions Current evidence indicates that the addition of oat beta-glucan to carbohydrate-containing meals reduces the postprandial glycemic response. However, the magnitude of the reduction depends on the dose and the molecular weight of the oat beta-glucan. Funding Sources INQUIS Clinical Research Ltd. (formerly GI Labs), and PepsiCo Global R&D.

356 Meal feeding compared with continuous feeding enhances insulin and amino acid signaling to translation initiation in skeletal muscle of pigs

Objectives: Meal feeding enhances skeletal muscle protein synthesis and lean growth more than continuous feeding in piglets. This enhanced muscle protein synthesis with meal feeding is associated with increased activation of mTORC1-dependent translation initiation. The mechanism underlying this response is unknown. We aimed to identify insulin and amino acid signaling components involved in the enhanced lean growth that results from meal feeding vs. continuous feeding in term-born pigs. Methods: Newborn piglets were fed for 21 d an equal amount of sow milk replacer (12.8 g protein and 155 kcal/(kg BW.d)) by gastrostomy tube either as intermittent bolus meals every 4 h (MEAL) or by continuous infusion (CON). After 21 d, gastrocnemius muscle was collected from CON, and before (MEAL-0) or 60 min after a meal (MEAL-60). Components of the insulin and amino acid signaling pathways up- and downstream of mTORC1 that regulate protein translation were measured. Results: Phosphorylation of AKT and TCS2 was greater in MEAL-60 than in MEAL-0 and CON (P &lt; 0.05). The association of Sestrin2 with GATOR2 was similar in CON and MEAL-0 but was lower in MEAL-60 (P &lt; 0.05). The abundances of RagA-mTOR, RagC-mTOR, and Rheb-mTOR, but not CASTOR1-GATOR2, complexes were higher in MEAL-60 than in CON and MEAL-0 (P &lt; 0.05). The phosphorylation of S6K1 and 4EBP1 was higher in MEAL-60 than CON and MEAL-0 (P &lt; 0.05). The abundances of Sestrin2, GATOR2, CASTOR1, RagA, RagC, and Rheb and the phosphorylation of eIF2alpha, eEF2, ERK1/2 and AMPK were unaffected by treatments. Conclusions: Our results demonstrate that the enhanced rate of skeletal muscle protein synthesis and lean growth with meal feeding compared with continuous feeding are due to the enhanced activation of both insulin and amino acid signaling pathways that result in the greater stimulation of translation initiation. Support: NIH HD085573, USDA CRIS 6250-51000-055, NIH HD072891, USDA NIFA 2013-67015-20438.

A Novel Automated System Yields Reproducible Temporal Feeding Patterns in Laboratory Rodents

ABSTRACT Background The impact of temporal feeding patterns remains a major unanswered question in nutritional science. Progress has been hampered by the absence of a reliable method to impose temporal feeding in laboratory rodents, without the confounding influence of food-hoarding behavior. Objective The aim of this study was to develop and validate a reliable method for supplying crushed diets to laboratory rodents in consistent, relevant feeding patterns for prolonged periods. Methods We programmed our experimental feeding station to deliver a standard diet [StD; Atwater Fuel Energy (AFE) 13.9% fat] or high-fat diet (HFD; AFE 45% fat) during nocturnal grazing [providing 1/24th of the total daily food intake (tdF/I) of ad libitum–fed controls every 30 min] and meal-fed (3 × 1-h periods of ad libitum feeding) patterns in male rats (Sprague-Dawley: 4 wk old, 72–119 g) and mice [C57/Bl6J wild-type (WT): 6 mo old, 29–37 g], and ghrelin-null littermates (Ghr−/−; 27–34 g). Results Grazing yielded accurate, consistent feeding events in rats, with an approximately linear rise in nocturnal cumulative food intake [tdF/I (StD): 97.4 ± 1.5% accurate compared with manual measurement; R2 = 0.86; tdF/I (HFD): 99.0 ± 1.4% accurate; R2 = 0.86]. Meal-feeding produced 3 nocturnal meals of equal size and duration in StD-fed rats (tdF/I: 97.4 ± 0.9% accurate; R2 = 0.90), whereas the second meal size increased progressively in HFD-fed rats (44% higher on day 35 than on day 14; P < 0.01). Importantly, cumulative food intake in grazing and meal-fed rats was identical. Similar results were obtained in WT mice except that less restricted grazing induced hyperphagia (compared with meal-fed WT mice; P < 0.05 from day 1). This difference was abolished in Ghr−/− mice, with meal initiation delayed and meal duration enhanced. Neither pattern elevated corticosterone secretion in rats, but meal-feeding aligned ultradian pulses. Conclusions We have established a consistent, measurable, researcher-defined, stress-free method for imposing temporal feeding patterns in rats and mice. This approach will facilitate progress in understanding the physiologic impact of feeding patterns.

Phosphatidylcholine from krill increases plasma choline and its metabolites in dogs

Background and Aim: Choline and its metabolites have multiple physiological roles in the body, which are important for muscle function, memory, methylation reactions, and hepatic lipid transport. This study aimed to investigate, if inclusion of phosphatidylcholine (PC) from Antarctic krill (Euphausia superba) can increase the concentration of choline and its metabolites in plasma of sled dogs in comparison to a control group. Materials and Methods: Ten adult Alaskan Huskies of both genders were supplemented with PC from 8% dietary krill meal inclusion for 6 weeks, while another ten dogs received no krill meal supplementation. Blood measurements of the two groups were taken at baseline and end of the study and compared for choline and its metabolite concentrations. Results: The choline concentration of the krill meal-supplemented dogs was significantly higher after 6 weeks of krill meal feeding compared to the control group (mean increase = 4.53 μmol/L in the supplemented versus 1.21 μmol/L in the control group, p=0.014). Furthermore, krill meal-supplemented dogs showed significantly more pronounced increases in betaine (p<0.001), dimethylglycine (p<0.01), trimethylamine-N-oxide (p<0.001), and trimethyllysine (p<0.001) compared to the control group. Significant correlations between changes in choline and changes in its metabolites were observed. Conclusion: The results showed that krill meal supplementation was associated with significantly higher plasma choline concentrations, which correlated with changed concentrations of choline metabolites.