Effects of nomadic grazing system and indoor concentrate feeding systems on performance, behavior, blood parameters, and meat quality of finishing lambs.

The objective of the study was to evaluate the effects of three production systems on growth performance, behavior, blood parameters, carcass characteristics, and meat quality. A total of 30 lambs (n = 10 lambs/treatment) were randomly assigned to three production systems that included rotational grazing (NG) and two different levels of concentrate (CON), one with medium (roughage/concentrate ratio 50:50% based on DM, MC) and one with high concentrate (roughage/concentrate ratio 30:70% based on DM, HC) during the 90-day fattening period. At the start of the experiment, all lambs averaged 90 ± 4 days of age (mean ± SD) and were slaughtered at an average of 180 ± 3 days (mean ± SD). CON-fed lambs had higher average daily gain and loin thickness than NG-fed lambs. The NG lambs spent more time eating, drinking, and standing, but less time resting and rumination than the CON-fed lambs. In addition, plasma lipid, ß-hydroxybutyrate, and urea levels were higher, while phosphorus levels were lower in NG-fed lambs than in CON-fed lambs. CON-fed lambs had better carcass yield, but gastrointestinal tract and rumen weights were lower than NG lambs. CON-fed lambs had higher pH values 0 h post mortem than the NG lambs; however, there was no effect of treatment on pH 24 h post mortem. The post-mortem color of the LD muscle of NG lambs had a higher lightness and yellowness index and a lower redness index than that of the LD muscle of CON-fed lambs. The results of this study showed that lambs fed CON had better carcass yield than lambs fed NG, although feed intake, feed conversion ratio (FCR), growth performance, carcass yield, and meat quality of lambs fed MC and HC were similar.

Nutrient intake, digestibility, and serum metabolites in dairy cows fed diets differing in starch concentration with palmitic acid or stearic acid supplementation postpartum.

The present study determined the effect of supplementing palmitic acid (PA) and stearic acid (SA) on the nutrient intake, digestibility, and serum metabolites of dairy cows fed two different starch levels during the postpartum period. Forty-four multiparous Holstein cows were used in a completed randomized block based on their parity and previous milk yield. Dietary treatments were arranged in a 2 × 2 arrangement with two dietary starch levels (HS: 260 g/kg of diet dry matter (DM) vs LS: 210 g/kg of diet DM) and two fat supplements rich in PA or SA at 15 g/kg of diet DM. Increasing the starch concentration of the postpartum diet improved organic matter (OM), ether extract (EE), crude protein (CP), and starch intake. Moreover, HS diets resulted in higher apparent digestibility of OM and CP but lower starch digestibility than LS diets. Feeding HS diets increased fecal starch output compared with LS diets. There was starch levels and FA supplements interaction for serum albumin and total antioxidant capacity (TAC), with higher concentrations in HSSA and LSPA compared to HSPA and LSSA. Significant correlations between performance and blood metabolites were observed in weeks 3 and 4. In week 3, a negative correlation was observed between serum TAC with milk protein (r = - 0.51) and lactose percentage (r = - 0.49) in the HS diet. However, non-esterified FA was correlated with the fat to protein ratio in the LS diet (r = 0.54). Moreover, in week 4, serum TAC was negatively related to the body condition score of the cows fed LS diet (r = 0.50), while there was no relationship for cows fed HS diets. In conclusion, feeding HS diets to postpartum cows increased nutrient intake and the digestibility of OM and CP compared with LS diets. The addition of SA to the HS diet may be more beneficial than PA in improving the oxidative status of dairy cows in the postpartum period.

Effects of group housing and incremental hay supplementation in calf starters at different ages on growth performance, behavior, and health.

The present study examined the effects of age at group housing and age at incremental hay supplementation in calf starters from 7.5 to 15% (dry matter, DM) and their interaction on growth performance, behavior, health of dairy calves, and development of heifers through first breeding. A total of 64 calves (n = 16 calves/treatment, 8 male and 8 female) were randomly assigned to 4 treatments in a 2 × 2 factorial arrangement, with age at group housing (early = d 28 ± 2, EG vs. late = d 70 ± 2, LG; 4 calves per group) and age at incremental hay supplementation of calf starters from 7.5 to 15% of DM (early = d 42 ± 2 d, EH vs. late = d 77 ± 2, LH) as the main factors. All calves (female and male) were weaned at 63 days of age and observed until 90 days of age. Heifer calves were managed uniformly from 90 days of age until first calving to evaluate the long-term effects of treatment. No interactions were observed between age at group housing and age at incremental hay to calves on starter feed intake, performance, calf health and behavior, and heifer development through first breeding, which was contrary to our hypothesis. The age at which incremental hay supplementation was administered had no effect on starter feed intake, growth performance, or heifer development until first calving. When EG calves were compared with LG calves, nutrient intake (starter, total dry matter, metabolizable energy, neutral detergent fiber, starch, and crude protein), average daily gain, and final body weight increased. In addition, frequency of standing decreased and time and frequency of eating increased in EG calves compared to LG calves. Overall, early group housing leads to improved growth performance in dairy calves with no negative effects on calf health compared to late group housing.

Feeding low-quality date leaves as a substitute to conventional forages in dairy cows diet: effects on digestibility, feeding behavior, milk yield, and feed efficiency.

This study investigated the possibility of integrating date leaves (DL) as a partial or complete substitute for conventional forage fibre sources into the diet of dairy cows. Nine Holstein cows were assigned to a replicated 3×3 Latin square design, and offered 1 of the 3 diets containing no DL (DL-0), or finely chopped DL partially (50%, DL-50) or completely (100%, DL-100) substituted for lucerne hay and maize silage. The replacement of the forages by DL was established such that the forage NDF (24.5%) was similar across diet despite the decreased forage: concentrate ratio from 0.45:0.55 to 0.33:0.67. Diets were similar in concentration of crude protein and starch, while the indigestible forage NDF (iNDF) increased from 7.2 to 15.4% of DM. Results showed that increasing DL inclusion linearly decreased nutrient intake and digestibility. Moreover, a trend toward a linear decrease in milk yield and percentage of milk protein and lactose were observed with increasing DL proportion in the diet. However, ruminal volatile fatty acids concentration, milk fat content, and feed efficiency were similar across the treatments. A quadratic trend was observed for eating and ruminating time by feeding DL, with the highest values found for cows fed DL-50. Replacing forages with finely chopped DL was effective to meet the fibre requirement, but reduced feed intake and milk yield possibly because of increased forage iNDF. However, conventional forages can be partially replaced with DL in the diet, particularly under forage shortage, because of maintained gross milk yield efficiency and reduced feed cost.

Synthesis and characterization of Zn/Al-LDH@SiO2 nanohybrid: Intercalation and release behavior of vitamin C.

Layered double hydroxide (LDH) nanoparticles (NPs) have potential applications for the loading and controlled release of drugs. This study investigated the synthesis of Zn/Al-LDH using the co-precipitation and ion-exchange methods, coating with SiO2 NPs and precise control of the release of vitamin C (VC). The results showed that more VC could be loaded by ion exchange. The surface of the VC-loaded LDH NPs was coated with SiO2 using the sol-gel and physical mixing methods. The structure, surface morphology, drug loading and thermostability were characterized and the drug release profile and release kinetics of the intercalated LDHs were studied. It was found that the SiO2 NPs more uniformly coated the LDH surfaces using the sol-gel process than the physical mixing method. The release behavior of VC from the intercalated nanohybrid is well described by the Avrami-Erofe'ev and Elovich models in the slow and fast stages. The sol-gel coated LDH@SiO2 nanohybrid system showed sustained drug delivery compared to the physical mixing method. The overall VC release from LDH increased more than 3-fold after coating with SiO2 NPs. Taken together, the Zn/Al-LDH@SiO2 coated by sol-gel should be considered as a potential sustained-release drug delivery system for VC.

Inoculation and co-inoculation of alfalfa seedlings with root growth promoting microorganisms (Piriformospora indica, Glomus intraradices and Sinorhizobium meliloti) affect molecular structures, nutrient profiles and availability of hay for ruminants.

Inoculation of alfalfa seedlings with root growth promoting microorganisms under semi-arid climate condition may improve biomass production and nutritive value. The current study aimed to investigate the effect of inoculation of alfalfa seedlings with Piriformospora indica (Pi) and co-inoculating Pi with Glomus intraradices (Gi + Pi) or Sinorhizobium meliloti (Sm + Pi) on hay yield, chemical composition, molecular structures by Fourier transformed infrared (FTIR) spectroscopy, in situ ruminal degradability and in vitro gas production. Seedlings were grown in experimental pots in a greenhouse until first cut and then transferred outside and cut a further 4 times. Biomass yield was similar across the treatments. Acid detergent fiber (ADF) concentration was higher in Pi than in control hay, and ADF decreased further with co-inoculation (P < 0.05). The ether extract (EE) concentration was lower for Pi and Gi + Pi compared with control hay, and control, Pi and Gi + Pi hays had lower EE concentration compared with Sm + Pi (P < 0.05). The FTIR spectroscopic vibration peak height ratio related to proteins (amide 1 + amide 2): total carbohydrate ratio was lower for the inoculation treatments compared with control hay (P < 0.05). In situ ruminal degradability of dry matter and organic matter were higher for hay of inoculated and co-inoculated seedlings than for control hay (P < 0.05). In conclusion, hay of alfalfa seedlings inoculated and co-inoculated with root growth promoting microorganisms had improved nutritional value compared with hay from non-treated alfalfa seedlings, and co-inoculation was the most effective, however, changes were relatively minor.

Rheological evaluations and in vitro studies of injectable bioactive glass-polycaprolactone-sodium alginate composites.

Composite pastes composed of various amounts of melt-derived bioactive glass 52S4 (MG5) and polycaprolactone (PCL) microspheres in sodium alginate solution were prepared. Rheological properties in both rotatory and oscillatory modes were evaluated. Injectability was measured as injection force versus piston displacement. In vitro calcium phosphate precipitation was also studied in simulated body fluid (SBF) and tracked using scanning electron microscopy, X-ray diffraction and FTIR analyses. All composite pastes were thixotropic in nature and exhibited shear thinning behavior. The magnitude of thixotropy decreased by adding 10-30 wt% PCL, while further amounts of PCL increased it again. Moreover, the composites were viscoelastic materials in which the elastic modulus was higher than viscous term. The pastes which were just made of MG5 or PCL had poor injectability, whereas the composites containing both of these constituents exhibited reasonable injectability. All pastes revealed adequate structural stability in contact with SBF solution. In vitro calcium phosphate precipitation was well observed on the paste made of MG5 and somewhat on the pastes with 10-40 wt% PCL, however the precipitated layer was amorphous in nature. Overall, the produced composites may be appropriate as injectable biomaterials for non-invasive surgeries but more biological evaluations are essential.

Effect of micro- and nanomagnetite on printing toner properties.

Toner is a main component of electrophotographic printing and copying processes. One of the most important ingredients of toner is magnetite (Fe3O4) which provides the tribocharging property for toner particles. In this study, nano- and microparticles of Fe3O4 were synthesized using the coprecipitation method and different amounts of lauric acid as a surfactant. The synthesized nano and micro Fe3O4 was then used as the charge control agent to produce toner by emulsion aggregation. The Fe3O4 and toner were characterized by X-ray powder diffraction (XRD), atomic gradient force magnetometry (AGFM), dynamic laser scattering (DLS), particle size analysis, differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). The results show that the optimum amount of surfactant not only reduced particle size but also reduced the magnetite properties of Fe3O4. It was found that the magnetite behavior of the toner is not similar to the Fe3O4 used to produce it. Although small-sized Fe3O4 created toner with a smaller size, toners made with micro Fe3O4 showed better magnetite properties than toner made with nano Fe3O4.

Dry chemical processing and ensiling of rice straw to improve its quality for use as ruminant feed.

In this study, changes in the chemical composition, pH, cell wall and degradability of ensiled rice straw were investigated when treated with alkali, acid, oxidant agents (1-11 %, w/w) and a combination of an oxidant with either an alkali (ALHP) or an acid (ACHP). The findings of the study revealed that ALHP had a lower efficiency in enhancing fibre degradability compared to alkali alone. Oxidant treatment showed no detectable changes in pH, dry matter (DM) and phenolic compound (PC) solubility, or in silica and fibre content, but led to increased esterified groups formed within the cell wall constituents (hemicellulose and lignin). Increasing acid concentration led to an exponential change in both pH and solubility of DM and hemicelluloses while it quadratically increased PC and silica solubility. Moreover, crystallinity, hydrogen bonding and esterification were enhanced under high acid concentrations (11 %), but decreased under mild acid conditions (5 %). Increased alkalinity led to the linear enhancement of DM and PC solubility. Solubility of silica and hemicellulose did not exhibit any significant changes with alkali concentration above 7 %. A gradual enhancement (29 %) was observed in ruminal DM degradability with increasing oxidant concentration, whereas exponential (91 %) and quadratic (23 %) enhancements were observed with alkaline and acid treatments, respectively. Treatment with acid showed observable reductions in the degradability of both cellulose and hemicellulose, whereas oxidant treatment reduced only that of hemicellulose. Treatment with 7 % alkali (pH ∼ 12) followed by ensiling appeared to be a promising process for improving rice straw quality.