Using mixed silages of sweet sorghum and alfalfa in total mixed rations to improve growth performance, nutrient digestibility, carcass traits and meat quality of sheep

Combining sweet sorghum (SS) with alfalfa for ensiling has the potential to make a high-quality silage with relatively a better nutrient balance. However, the existing data are insufficient about how changes in ratios of SS to alfalfa in different silage mixtures affect animal performance and meat quality. Therefore, the objective of this study was to determine the effect of feeding total mixed rations containing mixed silages of SS and alfalfa on growth performance, nutrient digestibility, carcass traits and meat quality of Karakul sheep. Five total mixed rations were formulated with different SS proportions at 100%, 80%, 60%, 40%, and 20% on a fresh weight basis. Thirty 4-month old male Karakul sheep with 25.5 ± 1.4 kg BW were randomly allocated into five treatment groups, each with six lambs for this experiment. The results indicated that the Karakul sheep consuming total mixed rations containing SS-Alfalfa (SS-AF) silage mixtures with a lower proportion of SS tended to increase nutrient digestibility, growth performance, carcass traits, and meat quality. Feeding diets with SS at 40% and 20% inclusion rate showed a significant linear increase in the apparent digestibility of DM, CP and NDF, as well as subcutaneous fat thickness and water holding capacity (P < 0.5). Moreover, reduction in SS inclusion rate in these diets caused significant (P < 0.05) linear and quadratic increases in DM intake, final BW, average daily gain, carcass weight, and the amino acid contents of meat (P < 0.05). Conversely, feeding diet with lower SS inclusion rate led to decrease in feed conversion ratio and shear force significantly (P < 0.05) for these sheep. It appears that 40% inclusion of SS was the optimal rate in making the SS-AF silage mixture for lambs to achieve a superior production performance and high-quality meat products in Karakul sheep. However, further research is needed to investigate the effect of feeding SS-AF silage mixtures alongside contrasting ingredients on rumen function, ruminal microorganisms and digestive enzyme activity of sheep and other ruminant animals.

Effects of nutrition restriction of fat- and lean-line broiler breeder hens during the laying period on offspring performance, blood biochemical parameters, and hormone levels

To evaluate the effects of maternal undernutrition on the performance, blood biochemical indexes, and hormone levels of broiler chicks, two broiler breeder lines (a fat line and lean line) were given either 100% or 75% of the daily feed intake recommended by the Chinese Ministry of Agriculture from 27 to 54 wk. All hens were fed the same basal corn-soybean diet. Fertile eggs were collected and hatched. All chicks were fed the same basal diet for 56 d. Then, chick performance, blood biochemical indexes, and hormone levels were measured. The results showed that there were interactions between maternal nutrition and line for some parameters, such as the kidney index, glucose, triglyceride, insulin, glucagon, leptin, and triiodothyronine (P < 0.05). Chicks of the fat line had a lower level of serum glucose, triglyceride, albumin, glutamic-pyruvic transaminase, insulin, and thyroxin than those of the lean line (P < 0.05), but the opposite trend was seen for birth weight, heart index, leptin, and triiodothyronine (P < 0.05). Maternal undernutrition decreased the birth weight and thymus index (day 28) of offspring (P < 0.05), but these effects disappeared by day 56. Maternal undernutrition decreased glucose (day 28), urea nitrogen (day 56), creatinine (day 56), glutamic-pyruvic transaminase (day 56), creatinine kinase (day 56), and leptin (day 56) levels in the offspring's serum (P < 0.05) but increased creatinine (day 28), total protein (day 28), glutamic-pyruvic transaminase (day 28), and glucagon (day 28) levels (P < 0.05). In conclusion, different lines have different metabolic processes. Maternal nutrition restriction during the laying period did have effects on the offspring, and the compensation by offspring reduced the effect of maternal nutrition restriction.

Effects of feeding sodium stearoyl-2-lactylate diets to lactating sows on performance, digestibility of nutrients, composition, and fat globule size in milk

The objective of this study was to determine the effects of feeding sodium stearoyl-2-lactylate (SSL) as a new feeding emulsifier diet with and without soybean oil (SO) on the milk fat globule (MFG) size, milk composition, digestibility of nutrients, and performance in lactating sows. Sixty sows (Large White × Landrace) were randomly assigned to 1 of 4 treatments according to a 2 × 2 factorial arrangement of treatments. Each treatment had 15 replicates composed of 1 sow. The factors included 1) the fat level (0% vs. 3% SO) and 2) the emulsifier content (0% vs. 0.1% SSL). Treatments included 1) Control (without SO and SSL), 2) SO (3% SO without SSL), 3) SSL (0.1% SSL without SO), and 4) SO + SSL (3% SO and 0.1% SSL). During the suckling period, sows in the SO + SSL group lost less back fat thickness ( < 0.05) compared to other groups; sows fed 3% SO diets consumed less feed ( < 0.05) compared to sows fed diets without SO, but there were no significant effects ( > 0.05) of dietary fat and its interaction with a dietary emulsifier on energy intake and the weaning-estrus interval. The digestibility of ether extract in the SO + SSL group was greater than in the SO group ( < 0.05). Moreover, greater digestibility of CP, Ca, and P in the SO+SSL group was observed compared to that of other groups ( < 0.05). Feeding the SO + SSL diet improved the concentrations of milk fat, protein, and total solids on d 11 of lactation compared to other diets ( < 0.05). Also, an interaction between supplemental SSL and SO was observed for the milk fat and total solids concentrations. The average diameter of MFG on d 11 of lactation was significantly decreased by the addition of 0.1% SSL compared to a diet with no SSL supplementation ( < 0.05). No significant differences among the dietary treatments were observed in cholesterol, triglyceride, high-density lipoprotein cholesterol, or low-density lipoprotein cholesterol in sows' plasma ( > 0.05). In conclusion, feeding a 0.1% SSL diet to lactating sows may decrease the average diameter of MFG and improve the digestibility of nutrients and composition of milk.

Correction to: Characterization of bactericidal efficiency, cell selectivity, and mechanism of short interspecific hybrid peptides

Facing rising global antibiotics resistance, physical membrane-damaging antimicrobial peptides (AMPs) represent promising antimicrobial agents. Various strategies to design effective hybrid peptides offer many advantages in overcoming the adverse effects of natural AMPs.

Characterization of bactericidal efficiency, cell selectivity, and mechanism of short interspecific hybrid peptides

Facing rising global antibiotics resistance, physical membrane-damaging antimicrobial peptides (AMPs) represent promising antimicrobial agents. Various strategies to design effective hybrid peptides offer many advantages in overcoming the adverse effects of natural AMPs. In this study, hybrid peptides from different species were investigated, and three hybrid antimicrobial peptides, LI, LN, and LC, were designed by combining the typical fragment of human cathelicidin-derived LL37 with either indolicidin, pig nematode cecropin P1 (CP-1) or rat neutrophil peptide-1 (NP-1). In an aqueous solution, all hybrid peptides had an unordered conformation. In simulated membrane conditions, the hybrid peptide LI displayed more β-turn and β-hairpin structures, whereas LN and LC folded into α-helix structures. The three interspecific hybrid peptides LI, LN, and LC exhibited different levels of antimicrobial activity against Gram-positive and Gram-negative bacteria. LI demonstrated the highest antimicrobial activity and cell selectivity. The results of the swimming motility indicated that LI repressed bacterial motility in a concentration-dependent method. Endotoxin binding assay demonstrated that hybrid peptide LI conserved the binding ability to LPS (polyanionic lipopolysaccharides) of its parental peptides. Fluorescence assays, flow cytometry, and SEM further revealed that hybrid peptide LI acted through different bacteriostatic mechanisms than LL37 and indolicidin and that LI killed bacterial cells via membrane damage. In summary, this study demonstrated that hybrid peptide LI produced by interspecific hybrid synthesis possessed strong cell selectivity and is a promising therapeutic candidate for drug-resistant bacteria infection.

Growth hormone-specific induction of the nuclear localization of porcine growth hormone receptor in porcine hepatocytes

The phenomenon of nuclear translocation of growth hormone receptor (GHR) in human, rat, and fish has been reported. To date, this phenomenon has not been described in a domestic animal (such as pig). In addition, the molecular mechanisms of GHR nuclear translocation have not been thoroughly elucidated. To this end, porcine hepatocytes were isolated and used as a cell model. We observed that porcine growth hormone (pGH) can induce porcine GHR's nuclear localization in porcine hepatocytes. Subsequently, the dynamics of pGH-induced pGHR's nuclear localization were analyzed and demonstrated that pGHR's nuclear localization occurs in a time-dependent manner. Next, we explored the mechanism of pGHR nuclear localization using different pGHR ligands, and we demonstrated that pGHR's nuclear translocation is GH(s)-dependent. We also observed that pGHR translocates into cell nuclei in a pGH dimerization-dependent fashion, whereas further experiments indicated that IMPα/β is involved in the nuclear translocation of the pGH-pGHR dimer. The pGH-pGHR dimer may form a pGH-GHR-JAK2 multiple complex in cell nuclei, which would suggest that similar to its function in the cell membrane, the nuclear-localized pGH-pGHR dimer might still have the ability to signal.

Dietary linseed oil in the maternal diet affects immunoglobulins, tissue fatty acid composition and expression of lipid metabolism-related genes in piglets

This experiment investigated the effects of supplementing the maternal diet with linseed oil (LSO) and soya bean oil (SBO) on immunoglobulins, the fatty acid composition and hepatic expression of lipid metabolism-related genes in piglets. Multiparous sows (twenty-four per diet) were fed on diets containing a supplement of either SBO or LSO during last week of gestation and lactation. The results indicated that supplementation of maternal diet with LSO could improve the weaning weight of piglets and average daily gain (ADG) (p < 0.05). The concentration of immunoglobulin G (IgG) and immunoglobulin A (IgA) was enhanced in sow plasma, colostrum and milk by the addition of LSO (p < 0.05). In addition, the concentration of 18: 3n-3 fatty acids was higher in the milk of LSO sows. Meanwhile, maternal supplementation with LSO increased the levels of plasma IgG, IgA and the tissues n-3 polyunsaturated fatty acid (PUFA) in piglets (p < 0.05). Correspondingly, the mRNA expression levels of hepatic ∆5-desaturase (D5D) and ∆6-desaturase (D6D) were higher, and fatty acid synthase (FAS) was lower in piglets from LSO-fed sows when compared with that in the SBO group. In conclusion, LSO supplementation of the maternal diet increases immunoglobulins, modifies the fatty acid composition and affects the gene of D5D and D6D expression of piglets.

Selenium Deficiency Affects the mRNA Expression of Inflammatory Factors and Selenoprotein Genes in the Kidneys of Broiler Chicks

The aim of this study was to investigate the influence of Se deficiency on the transcription of inflammatory factors and selenoprotein genes in the kidneys of broiler chicks. One hundred fifty 1-day-old broiler chicks were randomly assigned to two groups fed with either a low-Se diet (L group, 0.033 mg/kg Se) or an adequate Se diet (C group, 0.2 mg/kg Se). The levels of uric acid (UA) and creatinine (Cr) in the serum and the mRNA levels of 6 inflammatory factors and 25 selenoprotein genes in the kidneys were measured as the clinical signs of Se deficiency occurred at 20 days old. The results indicated that the contents of UA and Cr in the serum increased in L group (p < 0.05), and the mRNA levels of the inflammatory factors (NF-κB, iNOS, COX-2, and TNF-α) increased in L group (p < 0.05). Meanwhile, the mRNA levels of PTGEs and HO-1 were not changed. In addition, 25 selenoprotein transcripts displayed ubiquitous expression in the kidneys of the chicks. The mRNA levels of 14 selenoprotein genes (Dio1, Dio2, GPx3, Sepp1, SelH, SelI, SelK, Sepn1, SelO, SelW, Sep15, SelT, SelU, and SelS) decreased, and 9 selenoprotein genes (GPx1, GPx2, GPx4, SelPb, Txnrd1, Txnrd2, Txnrd3, SPS2, and SelM) increased in L group (p < 0.05), but the Dio3 and Sepx1 mRNA levels did not change. The results indicated that Se deficiency resulted in kidney dysfunction, activation of the NF-κB pathway, and a change in selenoprotein gene expression. The changes of inflammatory factor and selenoprotein gene expression levels were directly related to the abnormal renal functions induced by Se deficiency.

Dietary Supplementation of Magnesium Sulfate during Late Gestation and Lactation Affects the Milk Composition and Immunoglobulin Levels in Sows

This experiment was conducted to investigate the effects of dietary supplementation of magnesium sulfate (MgSO₄) during late gestation and lactation on sow and litter performance, fecal moisture, blood biochemistry parameters, immunoglobulin levels and milk composition in sows. Forty-eight sows (Yorkshire×Landrace, 4th to 5th parity) were randomly allocated to 1 of 4 dietary treatments supplemented with 0, 200, 400, or 600 mg/kg MgSO₄ (n = 12). The experiment started on day 90 of gestation and continued through day 21 of lactation. Blood samples were collected on day 107 of gestation, day 0 (farrowing) and 21 (weaning) of lactation for the analyses of the blood biochemistry parameters and immunoglobulin levels. The colostrum and milk samples were obtained on day 0 and 14 of lactation, respectively. Fecal samples were collected from the sows on day 107 of gestation as well as day 7 and 20 of lactation to determine fecal moisture content. The results showed that the survival percentage of piglets and the litter weight at weaning were decreased linearly (p<0.05) and other parameters of the sow or litter performance were not influenced (p>0.05) by MgSO₄ supplementation. The fecal moisture content of the sows were increased (p<0.05) linearly as dietary MgSO₄ increased on day 7 and 20 of lactation. Supplementation with MgSO₄ increased the plasma magnesium (Mg) level linearly (p<0.05) and had a trend to increase total protein level (p>0.05 and p<0.10). However, an increase in the dietary MgSO₄ level resulted in a linear decrease in the colostrum fat content (p<0.05). Dietary MgSO₄ supplementation enhanced the immunoglobulin G (IgG) level (linear, p<0.05) in plasma on day of farrowing and immunoglobulin A (IgA) level in colostrum (quadratic, p<0.05) and milk (linear, p<0.05) of the sows. These results indicated that supplementation with MgSO₄ during late gestation and lactation may have the potential to prevent sow constipation, but may also result in some negative effects.

Effectiveness of maifanite in reducing the detrimental effects of cadmium on growth performance, cadmium residue, hematological parameters, serum biochemistry, and the activities of antioxidant enzymes in pigs

This study was conducted to investigate the toxicity of cadmium and to evaluate the effectiveness of maifanite in preventing cadmium-induced adverse effects. Thirty-two crossbred pigs (Duroc × Landrace × Large white, sex balanced, 17.25 ± 0.07 kg average body weight) were randomly allotted to one of four dietary treatments in a 2 × 2 factorial arrangement, with eight replicates per treatment and one pig per replicate. The dietary treatments included two cadmium (as CdCl2) doses (0.32 and 30.49 mg/kg) and two maifanite doses (0 and 1%). The results showed that pigs treated with cadmium decreased their average daily feed intake (P < 0.05) and increased (P < 0.05) the feed/gain ratio. Cadmium was found in the tissues of pigs that were fed with cadmium-contaminated diets, but the level of cadmium was much lower when maifanite was added to the cadmium-contaminated diets. Ingestion of diets that were artificially contaminated with cadmium (30.49 mg/kg of cadmium) reduced (P < 0.05) the number of lymphocytes, the total erythrocyte count, the hemoglobin level, and the hematocrit. However, the activities of serum aspartate aminotransferase and gamma glutamyltransferase were increased (P < 0.05). The total protein level was lower (P < 0.05) in pigs fed with cadmium-contaminated diets. The contents of malondialdehyde increased (P < 0.05), while the total antioxidant capacity and the activities of total superoxide dismutase, glutathione peroxidase, glutathione S-transferase, and catalase decreased (P < 0.05) in pigs fed with cadmium-contaminated diets. Dietary addition of maifanite can, to some extent, prevent the negative effects associated with feeding cadmium diets (30.49 mg/kg of cadmium) to pigs.

Cell selectivity and interaction with model membranes of Val/Arg-rich peptides

Antimicrobial peptides are major components of the innate self-defence system and a large number of peptides have been designed to study the mechanism of action. In the present study, a small combinatorial library was designed to study whether the biological activity of Val/Arg-rich peptides is associated with targeted cell membranes. The peptides were produced by segregating hydrophilic residues on the polar side and hydrophobic residues on the opposite side. The peptides displayed strong antimicrobial activity against Gram-negative and Gram-positive bacteria, but weak haemolysis even at a concentration of 256 µM. CD spectra showed that the peptides formed α-helical-rich structure in the presence of negatively charged membranes. The tryptophan fluorescence and quenching experiments indicated that the peptides bound preferentially to negatively charged phospholipids over zwitterionic phospholipids, which corresponds well with the biological activity data. In the in vivo experiment, the peptide G6 decreased the bacterial counts in the mouse peritoneum and increased survival after 7 days. Overall, a high binding affinity with negatively charged phospholipids correlated closely with the cell selectivity of the peptides and some peptides in this study may be likely candidates for the development of antibacterial agents.

Effect of supplemental Bacillus cultures on rumen fermentation and milk yield in Chinese Holstein cows

Two experiments were conducted to study the effect of supplemental 100 g/day of live Bacillus cultures (2 x 10(11) cell of Bacillus subtilis and Bacillus licheniformis) on rumen fermentation as well as milk yield and composition in Chinese Holstein cows. In experiment 1, investigating 3 x 10 cows, milk yield and milk protein were increased by using B. licheniformis (p < 0.05) in comparison with an unsupplemented group and the B. subtilis group. Body weight was not significantly affected by Bacillus culture supplementation (p > 0.05). Percentage of milk fat and lactose was not significantly different between treatments (p > 0.05). But milk protein increased with B. licheniformis supplementation (p < 0.05). In experiment 2, carried out with three non-lactating ruminally and duodenally fistulated cows, results showed that B. licheniformis supplementation increased microbial crude protein flow into duodenum (p < 0.05) and decreased the ammonia nitrogen concentration in ruminal fluid at 0.5 h, 1 h, 3 h, 6 h after morning feeding (p < 0.05). Bacillus licheniformis supplementation increased total VFA and acetate concentration in ruminal fluid at 0.5 h, 1 h, 3 h, 6 h after morning feeding (p < 0.05). Bacillus subtilis had no significant effect on rumen fermentation characteristics, duodenal microbial N flow and ruminal apparent nutrient digestibility (p > 0.05). Bacillus licheniformis increased ruminal apparent nutrient digestibility of neutral detergent fibre, acid detergent fibre, and organic matter (p < 0.05).

The influence of temperature on the threonine and tryptophan requirements of young broiler chicks

Two experiments were conducted to investigate the influence of a warm environment (35 degrees C) on the threonine and tryptophan requirements of young broiler chicks from 7 to 18 or 21 d of age. Seven hundred forty (experiment 1) and one thousand eight (experiment 2) 1-d-old Cobb x Cobb straight-run broiler chicks were raised in wire-floored battery brooders in moderate temperature rooms (33 to 34 degrees C). For the first 7 d, all chicks were fed a standard corn-soybean-meal-based crumbled starter diet. On d 7, six chicks each (experiment 1) and eight chicks each (experiment 2) were randomly assigned to individual pens. In experiment 1, chicks were fed a corn-peanut meal basal diet supplemented with six levels of threonine (0.630, 0.651, 0.673, 0.715, 0.758, or 0.800% of the diet). In experiment 2, chicks were fed a corn-corn gluten meal based basal diet supplemented with six levels of tryptophan (0.090, 0.115, 0.140, 0.165, 0.190, or 0.215% of the diet). Each dietary treatment was repeated with three pens in each room and three rooms at each temperature. Three rooms were set at a moderate temperature of 25 degrees C, and the other three rooms were set at a warmer temperature of 35 degrees C. Body weight gain, feed consumption, and feed conversion ratio were measured. The threonine requirements of young broiler chicks were 0.733 +/- 0.016% (R2 = 0.59) and 0.752 +/- 0.046% (R2 = 0.25) for body weight gain, and 0.744 +/- 0.016% (R2 = 0.67) and 0.722 +/- 0.016% (R2 = 0.47) for feed conversion ratio at 25 and 35 degrees C, respectively (broken-line linear model). The tryptophan requirements of young broiler chicks were 0.151 +/- 0.004% (R2 = 0.85) and 0.144 +/- 0.003% (R2 = 0.89) for body weight gain, 0.144 +/- 0.003% (R2 = 0.88) and 0.142 +/- 0.003% (R2 = 0.88) for feed consumption, and 0.146 +/- 0.005% (R2 = 0.76) and 0.127 +/- 0.002% (R2 = 0.94) for feed conversion ratio at 25 and 35 degrees C, respectively. On average, the threonine and tryptophan requirements of broiler chicks at 35 degrees C were very similar to those kept at 25 degrees C.

Oligoclonality of serum immunoglobulin G antibody responses to Streptococcus pneumoniae capsular polysaccharide serotypes 6B, 14, and 23F

Serum antibodies (Abs) specific for the capsular polysaccharides of Streptococcus pneumoniae provide protection against invasive pneumococcal disease. Previous studies indicate that Abs to pneumococcal polysaccharide (PPS) serotypes 1 and 6B have limited clonal diversity. To determine if restricted diversity was a feature common to other PPS specificities, we examined the light (L)-chain expression and isoelectric heterogeneity of type 6B, 14, and 23F Abs elicited in 15 adults following PPS vaccination. At the population level, both PPS-6B and PPS-14 Abs expressed kappa and lambda chains, although 6B Abs more frequently expressed lambda chains lambda and 14 Abs more frequently expressed kappa chains. In individual sera, Abs were generally skewed towards either kappa or lambda expression. 23F-specific Abs had predominantly kappa chains. Isoelectric focusing analyses showed that sera contained one or at most a few immunoglobulin G Ab spectrotypes to all three respective capsular serotypes, a result indicative of oligoclonality. A sequence analysis of a purified PPS-14-specific Ab having a single spectrotype gave uniform amino-terminal sequences for both the heavy chain (V(H)III subgroup) and the L chain (kappaIII-A27 V region). From these results we conclude that within individual adults, serum Ab responses to PPS serotypes 6B, 14, and 23F derive from a small number of dominant B-cell clones, and consequently variable-region expression is probably individually limited as well. Oligoclonality appears to be a general characteristic of human PPS-specific Ab repertoires, and we suggest that this property could lead to individual differences in Ab fine specificity and/or functional activity against encapsulated pneumococci.

Effect of dietary phytate on growth and selenium status of chicks fed selenite or selenomethionine

1. An experiment was conducted to study the effect of dietary phytate on the selenium status of chicks fed on a semi-purified diet with or without supplements of sodium selenite or selenomethionine (200 micrograms Selenium/kg). 2. Assessment included measurement of growth and activity of glutathione peroxidase (GSHPx) (EC.1.11.1.9), an enzyme that limits damage by free radical species arising from oxygen metabolism by catalysing the reduction of hydrogen peroxide and lipid hydroperoxides. In addition, information was obtained on forms of selenium in blood, liver, kidney, heart and muscle, distinguishing between selenide-Se, reducible-Se and non-reducible-Se. 3. Phytate caused significant reductions in growth, food consumption and food conversion efficiency. Supplementary selenium was without effect on growth but significantly increased GSHPx activity in all tissues. Phytate also increased GSHPx activity in blood and heart, and in muscle in the absence of supplementary selenium, but decreased the activity in kidney. 4. Concentrations of all forms of tissue selenium were significantly increased by supplementary selenium. In general, there was greater deposition from selenomethionine than from selenite and most was in non-reducible form. 5. Phytate increased selenium in all tissues except muscle; it is not clear if this resulted from increased absorption or increased retention. It increased reducible-Se in blood, liver and heart and non-reducible-Se in blood and kidney. Tissue concentrations of selenide-Se were highly variable: presence or absence of phytate contributed to some significant interactions. 6. The results suggest that there is a positive relationship between phytate and selenium status in chicks, in contrast to its negative effect on growth.