Lactation responses of Holstein dairy cows to supplementation with a combination of trace minerals produced using the advanced chelate compounds technology

Advanced chelate compounds technology is a novel technology that introduces a new generation of chelates to deliver trace elements better by polymerization of organic acids. In the present study, the over-supplementation effect of Bonzaplex7 supplement, which is designed based on the aforementioned technology, was evaluated on milk yield of dairy Holstein cattle through two experiments. In the first experiment (exp. I), 24 primiparous dairy cows were randomly assigned to one of 3 groups: (1) without over-supplementation (control); (2) daily allowance of 7 g/cow Bonzaplex7 containing Co (12 mg), Cr (3.5 mg), Cu (126 mg), Fe (56 mg), Mn (196 mg), Se (2 mg), and Zn (357 mg) (Bonzaplex7); and (3) daily allowance of the same amounts of all of the trace minerals in amino acid complex form (AA). In the second experiment (exp. II), 170 multiparous dairy cows received either 7 g/day/cow Bonzaplex7 (85 cows, test) or no additional supplement (85 cows, NS). In exp. I, the milk yields in control, Bonzaplex7, and AA were 34.30, 36.46, and 35.83 kg/day, respectively (P = 0.528). No significant differences in milk composition were detected among the groups. In exp. II, however, higher milk fat and energy-corrected milk yield were observed in test compared with NS. Both Bonzeplex7 and AA elevated the plasma concentrations of Cu, Mn, and Se. The results provided evidence that supplementing dairy cows with a combination of trace minerals which produced using the advanced chelate compounds technology has a potential to improve milk fat and to decrease disease susceptibility under stressed conditions.

Feather HSP70: a novel non-invasive molecular marker for monitoring stress induced by heat exposure in broilers

Poultry well-being and economic burden due to heat stress (HS) are of great importance to the poultry industry. Efficient design and effective evaluation of any strategies to alleviate the adverse effects of HS on poultry production require an accurate measurement of stress. However, current methods for monitoring stress in poultry are less than ideal, as they are invasive or subjective, and therefore variable. Here, we demonstrated that HSP70, the well-established intracellular stress chaperone, is expressed in chicken feather and is responsive to HS, and could therefore be used as a stress marker. Growing feathers were collected from the same bird (Cobb500, n = 9) in the morning (barn temperature 24°C) and afternoon (barn temperature 29.5°C) in the summer (2016 June 21) in Arkansas, USA. In the afternoon, the birds were panting and their core body temperatures were significantly higher compared to the morning time, as illustrated by iButton data thermo-loggers. Concomitantly, blood HSP70 mRNA and feather HSP70 expression (mRNA and protein) were significantly increased in the afternoon compared to the morning time. Similarly, HSP70 protein expression in the duodenum was also significantly higher in the afternoon compared to the morning period. Together, these finding identify feather HSP70 as a novel non-invasive molecular signature that mirrors the intracellular and systemic stress, which can be useful to monitor well-being of chickens and other avian species under different challenges.

Noni (Morinda citrifolia) Modulates the Hypothalamic Expression of Stress- and Metabolic-Related Genes in Broilers Exposed to Acute Heat Stress

Heat stress (HS) adversely affects growth performance and inflicts heavy economic losses to the poultry industry. There is, therefore, a critical need to identify new alternative strategies to alleviate the negative effects induced by HS. The tropic medicinal plant, Morinda citrifolia (Noni), is being used in livestock nutrition, however the literature is limited and conflicting for its impact on growth performance. The present study aimed to determine the effect of Noni on feeding and drinking behavior as well as on the hypothalamic expression of stress- and metabolic-related genes in broiler chickens exposed to acute HS. A total of 480 1 day-old male broiler chicks were randomly assigned to 12 controlled environmental chambers. Birds were subjected to two environmental conditions (TN, 25°C vs. HS, 35°C for 2 h) and fed two diets (control vs. 0.2% Noni) in a 2 × 2 factorial design. Feed intake and core body temperature (BT) were recorded during HS period. Blood was collected and hypothalamic tissues were harvested for target gene and protein analyses. Acute HS-broilers exhibited higher BT (~1°C), spent less time eating with a significant decrease in feed intake, and spent more time drinking along with higher drinking frequency compared to those maintained under TN conditions. Although Noni supplementation did not improve feed intake, it significantly delayed (~30 min) and reduced the BT-induced by HS. At molecular levels and under HS conditions, Noni supplementation down regulated the hypothalamic expression of HSP90 and its related transcription factors HSF1, 2, and 4, increased orexin mRNA levels, and decreased the phosphorylation levels of AMPKα1/2^Thr172 and mTOR^Ser2481. Together, these data indicated that Noni supplementation might modulate HS response in broilers through central orexin-AMPK-mTOR pathways.

Effect of Morinda citrifolia (Noni)-Enriched Diet on Hepatic Heat Shock Protein and Lipid Metabolism-Related Genes in Heat Stressed Broiler Chickens

Heat stress (HS) has been reported to alter fat deposition in broilers, however the underlying molecular mechanisms are not well-defined. The objectives of the current study were, therefore: (1) to determine the effects of acute (2 h) and chronic (3 weeks) HS on the expression of key molecular signatures involved in hepatic lipogenic and lipolytic programs, and (2) to assess if diet supplementation with dried Noni medicinal plant (0.2% of the diet) modulates these effects. Broilers (480 males, 1 d) were randomly assigned to 12 environmental chambers, subjected to two environmental conditions (heat stress, HS, 35°C vs. thermoneutral condition, TN, 24°C) and fed two diets (control vs. Noni) in a 2 × 2 factorial design. Feed intake and body weights were recorded, and blood and liver samples were collected at 2 h and 3 weeks post-heat exposure. HS depressed feed intake, reduced body weight, and up regulated the hepatic expression of heat shock protein HSP60, HSP70, HSP90 as well as key lipogenic proteins (fatty acid synthase, FASN; acetyl co-A carboxylase alpha, ACCα and ATP citrate lyase, ACLY). HS down regulated the hepatic expression of lipoprotein lipase (LPL) and hepatic triacylglycerol lipase (LIPC), but up-regulated ATGL. Although it did not affect growth performance, Noni supplementation regulated the hepatic expression of lipogenic proteins in a time- and gene-specific manner. Prior to HS, Noni increased ACLY and FASN in the acute and chronic experimental conditions, respectively. During acute HS, Noni increased ACCα, but reduced FASN and ACLY expression. Under chronic HS, Noni up regulated ACCα and FASN but it down regulated ACLY. In vitro studies, using chicken hepatocyte cell lines, showed that HS down-regulated the expression of ACCα, FASN, and ACLY. Treatment with quercetin, one bioactive ingredient in Noni, up-regulated the expression of ACCα, FASN, and ACLY under TN conditions, but it appeared to down-regulate ACCα and increase ACLY levels under HS exposure. In conclusion, our findings indicate that HS induces hepatic lipogenesis in chickens and this effect is probably mediated via HSPs. The modulation of hepatic HSP expression suggest also that Noni might be involved in modulating the stress response in chicken liver.

Surface wetting strategy prevents acute heat exposure-induced alterations of hypothalamic stress- and metabolic-related genes in broiler chickens

Heat stress (HS) is devastating to poultry production worldwide, yet its biology and molecular responses are not well defined. Although advances in management strategy have partially alleviated the negative impact of HS, productivity still continues to decline when the ambient temperature rises. Therefore, identifying mechanism-based approaches to decrease HS susceptibility while improving production traits is critical. Recently, we made a breakthrough by applying a surface wetting strategy and showing that it improves growth performance compared with the current conventional cooling system. In the present study, we aimed to further define molecular mechanisms associated with surface wetting in ameliorating HS productivity loss in broilers. Five-week-old broiler chickens were exposed to acute HS (35°C for 2 h) alone or in combination with surface wetting. A control group was maintained at thermoneutral conditions (25°C). Core body temperature (BT) and feed intake were recorded. Blood was collected and hypothalamic tissues (main site involved in the regulation of energy homeostasis) were harvested to determine the expression profile of stress- and metabolic-related genes. Surface wetting prevents HS from increasing BT and plasma corticosterone levels ( < 0.05) and improves feeding and drinking behaviors. At molecular levels, surface wetting blocks the activation of hypothalamic heat shock protein and adenosine monophosphate-activated protein-induced by HS and significantly modulates the expression of feeding-related hypothalamic neuropeptides (agouti-related protein, proopiomelanocortin, orexin, orexin receptor, and leptin receptor). Taken together, our data represent the first evidence that surface wetting alleviates systemic and intracellular stress induced by HS and preserves the intracellular energy status, which, in turn, may result in improved broiler well-being and growth performance.