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Herbal supplements containing diverse phytochemicals have been proven to improve digestibility, beneficial serum metabolites, milk yield, and quality in cows. However, the temperature sensitivity of phytochemicals in herbs complicates their practical use as livestock supplements. In response, this study aimed to assess how shade-dried plantain, lemongrass, and their combination influence cow performance, digestibility, serum and milk antioxidants, and milk fatty acids. Forty multiparous mid-lactating Holstein-tropical crossbred cows were randomly assigned to four groups (n = 10) for 63 days in a completely randomized design with covariates adjustment. The control group received a basal diet (14.9% crude protein, 11.0 MJ metabolizable energy/kg dry matter (DM)) without herbs. The herbs-supplemented groups received shade-dried powder (per cow/day) of either 100 g plantain (plantain), 100 g lemongrass (lemongrass), or 50 g each of plantain and lemongrass (combined), along with the basal diet. Compared with the control, the plantain or lemongrass group presented improved performance, i.e., DM consumption (3–4%), milk (10–11%) and its components yield (p ≤ 0.05). Similar to the control, the combined group had no effect on performance or digestibility, whereas the digestibility of all nutrients in the plantain or lemongrass group substantially increased. Herbs-supplementation reduced serum bad-cholesterol and urea-nitrogen while increasing good-cholesterol and albumin compared with the control (p < 0.01). Notably, 4–8% serum and 8–23% milk antioxidants were greater in the herbs-supplemented groups than the control, while the lemongrass had the optimum milk β-carotene. Substantially, herbs-supplementation resulted in a 6–10% higher unsaturated fatty acids (USFAs), whereas the combined group presented a 3.56-fold greater n-3 fatty acids than the control. Significantly, the plantain or lemongrass group presented better benefit‒cost‒ratio than the combined and control. Therefore, shade-dried herbs-supplementation improved the beneficial serum metabolites, serum and milk antioxidants, and milk USFAs in cows. Additionally, shade-dried plantain or lemongrass enhanced cow DM consumption, digestibility, milk yield, and profitability. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to compare the body weight (BW), milk yield, nutritional status, and profitability of moderate genetic (MG) and high genetic (HG) merit of Holstein crossbred (HC) cows in a tropical region under the existing farming system. Materials and Methods: Data was gathered from 204 nursing cows of MG (n = 99) and HG (n = 105) merit of HC cows throughout a year in the dairy zone Keraniganj, Bangladesh. HC cows of MG and HG merit contained 50.0%-67.7% and 75.0%-87.5% Holstein blood, respectively. Data on genetic merit, BW, lactation stage and number, daily milk yield, feed intake, feed, and milk price were documented. All variables were except genetic merit analyzed using one-way analysis of variance. Results: HC cows of MG and HG merit had 433 and 493 kg BW (p < 0.01), and daily produced 11.99 and 14.06 kg milk (p = 0.07) with having 0.99 and 1.15 feed efficiency (p = 0.06), respectively but dry matter intake did not vary (p > 0.05). HC cows of both genetic merit daily offered surplus metabolizable energy and digestible crude protein through roughage and concentrate than their requirement (p > 0.05). The milk production cost of both genetic merit HC cows was alike (p > 0.05), whereas almost two times more profit was obtained in HG merit HC compared to MG merit HC cows (p < 0.05). Conclusion: HC cows of HG merit showed superior potentiality of milk yield, profit, and feed efficiency, whereas MG merit HC cows revealed inferior feed efficiency and milk yield. [ABSTRACT FROM AUTHOR]

A total of 200 day-old COBB-500 chicks were randomly allocated into four dietary treatments with five replications and ten birds per replicate for 28 days to select the most effective forms of plantain herb for broiler performance and meat quality. The control diet (CL-D) and different forms of plantain diets were based on corn-soybean meal that was iso-caloric and iso-nitrogenous. The different forms of plantain diets were fresh plantain-diet (FP-D): CL-D + fresh-plantain, shade-dried plantain-diet (SP-D): CL-D + shade-dried plantain powder, and blanched-dried plantain-diet (BP-D): CL-D + blanched-dried plantain powder. Plantain herb was given at a 1.0% dry matter basis. Daily feed consumption and weekly body weight were noted, whereas blood samples were taken and a meat panel test was confirmed by specialists in meat on day 28. Birds given the different forms of plantain diets revealed a 6-10% greater body weight gain compared to the CL-D (P < 0.05). Plantain diets in different forms showed a 3–6% better feed, crude protein, and metabolizable energy conversion ratio compared to the CL-D (P < 0.05), but no difference was observed between BP-D and SP-D (P > 0.05). Compared to the CL-D, birds fed the different forms of plantain diets reduced serum triglyceride and total cholesterol by 4–11% and 6–9%, respectively (P < 0.05). Birds that were fed the different forms of plantain diets had a lower meat ether extract and a greater meat saturation index (redness) than the CL-D (P < 0.05). Compared to the CL-D, birds fed the redifferent forms of plantain diets showed better meat juiciness, tenderness, and acceptance (P < 0.05). Therefore, fresh plantain demonstrated superior broiler performance and improved meat quality, whereas both blanched-dried and shade-dried plantain powder might be considered for inclusion in feed formulations to enhance broiler performance and meat quality. [ABSTRACT FROM AUTHOR]

Objectives: Current research aimed to compare the effects of fungal and bacterial phytase with or without citric acid (CA) on growth performance, serum mineral profile, bone quality, and nutrient retention in birds given non-phytate phosphorus (nPP)-deficient diets. Materials and Methods: A total of 216 Indian River broiler chicks were disturbed into six groups, namely, i) positive control (PC), ii) negative control (NC) contained 0.2% lower nPP than that in the PC diet, iii) NC + fungal phytase (Aspergillus niger), iv) NC + fungal phytase with 2% CA, v) NC + bacterial phytase (Escherichia coli), and vi) NC + bacterial phytase with 2% CA. Results: Compared to the PC group, the NC group showed poor performance, serum phosphorus (P) content, P retention, and bone quality. However, with the inclusion of phytase, all these phenomena were improved. The addition of bacterial phytase showed better values compared with fungal phytase. The main effects of phytase were significant for the feed conversion ratio (FCR), metabolizable energy conversion ratio (MECR), and P retention. The addition of CA, either with fungal or bacterial phytases, did not show considerable beneficial effects on overall performances. However, the main effects of CA were significant on the FCR, MECR, and crude protein conversion ratio. Conclusion: Incorporating bacterial and fungal phytase into low-nPP diets enhanced the broiler's performance. The effects of bacterial phytase were more apparent than those of fungal phytase. However, the efficacy of phytase based on the source might relate to dose, and other factors need further investigation. [ABSTRACT FROM AUTHOR]

The survival of a bacterium with a depleted oxygen or nutrient supply is important for its long-term persistence inside the host under stressful conditions. We studied a gene, dps, from Mycobacterium smegmatis, encoding a protein, Dps (for DNA binding protein from starved cells), which is overexpressed under oxidative and nutritional stresses and provides bimodal protection to the bacterial DNA. Characterization of the dps promoter in vivo is therefore important. We cloned a 1-kb putative promoter region of the dps gene of M. smegmatis in an Escherichia coli-Mycobacterium shuttle vector, pSD5B, immediately upstream of the lacZ gene. Promoter activities were assayed in vivo both in solid medium and in liquid cultures by quantitative [beta]-galactosidase activity measurements. To characterize the minimal promoter region, a 200-bp fragment from the whole 1-kb sequence was further cloned in the same vector, and in a similar way, [beta]-galactosidase activity was quantitated. Primer extension analysis was performed to determine the +1 transcription start site of the gene. Point mutations were inserted in the putative promoter sequences in the -10 and -20 regions, and the promoter sequence was confirmed. The promoter was not recognized by purified M. smegmatis core RNA polymerase reconstituted with purified Mycobacterium tuberculosis [[sigma].sup.A] or [[sigma].sup.B] during multiple- and single-round in vitro transcription assays. Promoter-specific in vivo pull-down assays with an immobilized 1-kb DNA fragment containing the dps promoter established that extracellular function sigma factors were associated with this starvation-inducible promoter. Single-round transcription at the dps promoter further supported the idea that only core RNA polymerase reconstituted with [[sigma].sup.F] or [[sigma].sup.H] can generate proper transcripts.

A graph theoretical method is used to predict the important amino acid residues for further mutation studies of the Dps trimers from Mycobacterium smegmatis. It is shown how the F47 residue is crucial for dodecamerization.

In this work, we have tried to emphasize the connection between mycobacterial growth and regulation of gene expression. Utilization of multiple carbon sources and diauxic growth helps bacteria to regulate gene expression at an optimum level so that the inhospitable conditions encountered during nutrient depletion can be circumvented. These aspects will be discussed with respect to mycobacterial growth in subsequent sections. Identification and characterization of genes induced under such conditions is helpful to understand the physiology of the bacterium. Although it is necessary to compare the total expression profile of proteins as they transit from vegetative growth to stationary phase, at times a lot of insights can be deciphered from the expression pattern of one or two proteins. We have compared the protein expression and sigma factor selectivity of two such proteins in M. smegmatis to understand the differential regulation of genes playing diverse function in the same species. Some newer insights on the structure and function of one of the Dps proteins are also explained. © 2009 IUBMB IUBMB Life, 62(1):67–77, 2010 [ABSTRACT FROM AUTHOR]

The Dps (DNA-binding protein from starved cells) proteins from Mycobacterium smegmatis MsDps1 and MsDps2 are both DNA-binding proteins with some differences. While MsDps1 has two oligomeric states, with one of them responsible for DNA binding, MsDps2 has only one DNA-binding oligomeric state. Both the proteins however, show iron-binding activity. The MsDps1 protein has been shown previously to be induced under conditions of starvation and osmotic stress and is regulated by the extra cellular sigma factors σH and σF. We show here, that the second Dps homologue in M. smegmatis, namely MsDps2, is purified in a DNA-bound form and exhibits nucleoid-like structures under the atomic force microscope. It appears that the N-terminal sequence of Dps2 plays a role in nucleoid formation. MsDps2, unlike MsDps1, does not show elevated expression in nutritionally starved or stationary phase conditions; rather its promoter is recognized by RNA polymerase containing σA or σB, under in vitro conditions. We propose that due to the nucleoid-condensing ability, the expression of MsDps2 is tightly regulated inside the cells. [ABSTRACT FROM AUTHOR]

The Dps (DNA-binding protein from starved cells) proteins from Mycobacterium smegmatis MsDps1 and MsDps2 are both DNA-binding proteins with some differences. While MsDps1 has two oligomeric states, with one of them responsible for DNA binding, MsDps2 has only one DNA-binding oligomeric state. Both the proteins however, show iron-binding activity. The MsDps1 protein has been shown previously to be induced under conditions of starvation and osmotic stress and is regulated by the extra cellular sigma factors σH and σF. We show here, that the second Dps homologue in M. smegmatis, namely MsDps2, is purified in a DNA-bound form and exhibits nucleoid-like structures under the atomic force microscope. It appears that the N-terminal sequence of Dps2 plays a role in nucleoid formation. MsDps2, unlike MsDps1, does not show elevated expression in nutritionally starved or stationary phase conditions; rather its promoter is recognized by RNA polymerase containing σA or σB, under in vitro conditions. We propose that due to the nucleoid-condensing ability, the expression of MsDps2 is tightly regulated inside the cells. [ABSTRACT FROM AUTHOR]