Influence of the main cereal and feed form of the rearing phase diets on performance, digestive tract, and body traits of brown-egg laying pullets from hatch to 17 weeks of age

We hypothesize that pullets could respond similarly, independent of feed form, to the feeding of diets based on corn or wheat supplemented with adequate NSP enzymes. Also, pullets would quickly adapt their gastrointestinal tract and modify productive performance accordingly, when switched from crumbles to mash feeds. The aim of this research was to evaluate the effects of feeding crumbles for different periods of time, followed by feeding mash to 17 wk of age, on performance, gastrointestinal tract development, and body measurements of brown-egg laying pullets fed diets based on corn or wheat

Feed form and energy concentration of the diet affect growth performance and digestive tract traits of brown-egg laying pullets from hatching to 17 weeks of age

The influence of feed form and energy concentration of the diet on growth performance and the development of the gastrointestinal tract (GIT) was studied in brown-egg laying pullets. Diets formed a 2 x 5 factorial with 2 feed forms (mash vs. crumbles) and 5 levels of energy differing in 50 kcal AMEn/kg. For the entire study (0 to 17 wk of age) feeding crumbles increased ADFI (52.9 vs. 49.7 g; P  0.05) by energy content of the diet. At 5, 10, and 17 wk of age, the relative weight (RW, % BW) of the GIT and the gizzard, and gizzard digesta content were lower (P < 0.05 to P < 0.001) and gizzard pH was higher (P < 0.05 to P < 0.001) in pullets fed crumbles than in pullets fed mash. Energy concentration of the diet did not affect any of the GIT variables studied. In summary, feeding crumbles improved pullet performance and reduced the RW of the GIT and gizzard, and increased gizzard pH at all ages. An increase in the energy content of the diet improved FCR from 0 to 17 wk of age. The use of crumbles and the increase in the AMEn content of the diet might be used adventageously when the objetive is to increase the BW of the pullets. However, crumbles affected the development and weight of the organs of the GIT, which might have negative effects on feed intake and egg production at the beginning of the egg laying cycle

Correlation between ileal digestibility of amino acids and chemical composition of soybean meals in broilers at 21 days of age

The correlations between chemical composition and coefficient of standardized ileal digestibility (CSID) of crude protein (CP) and amino acids (AA) were determined in 22 soybean meal (SBM) samples originated from USA (n = 8), Brazil (BRA; n = 7) and Argentina (ARG; n = 7) in 21-day old broilers. Birds were fed a commercial maize-SBM diet from 1 to 17 days of age followed by the experimental diets in which the SBM tested was the only source of protein (205 g CP/kg) for three days. Also, in vitro nitrogen (N) digestion study was conducted with these samples using the two-step enzymatic method. The coefficient of apparent ileal digestibility (CAID) of the SBM, independent of the origin, varied from 0.820 to 0.880 for CP, 0.850 to 0.905 for lysine (Lys), 0.859 to 0.907 for methionine (Met) and 0.664 to 0.750 for cysteine (Cys). The corresponding CSID values varied from 0.850 to 0.966 for CP, 0.891 to 0.940 for Lys, 0.931 to 0.970 for Met and 0.786 to 0.855 for Cys. The CSID of CP and Lys of the SBM were positively correlated with CP (r = 0.514; P menor que 0.05 and r = 0.370; P = 0.09, respectively), KOH solubility (KOH sol.) (r = 0.696; P menor que 0.001 and r = 0.619; P menor que 0.01, respectively), trypsin inhibitor activity (TIA) (r = 0.541; P menor que 0.01 and r = 0.416; P = 0.05, respectively) and reactive Lys (r = 0.563; P menor que 0.01 and r = 0.486; P menor que 0.05) values, but no relation was observed with neutral detergent fiber and oligosaccharide content. No relation between the CSID of CP determined in vivo and N digestibility determined in vitro was found. The CSID of most key AA were higher for the USA and the BRA meals than for the ARG meals. For Lys, the CSID was 0.921, 0.919 and 0.908 (P menor que 0.05) and for Cys 0.828, 0.833 and 0.800 (P menor que 0.01) for USA, BRA and ARG meals, respectively. It is concluded that under the conditions of this experiment, the CSID of CP and Lys increased with CP content, KOH sol., TIA and reactive Lys values of the SBM. The CSID of most limiting AA, including Lys and Cys, were higher for USA and BRA meals than for ARG meals

Effects of fiber inclusion on growth performance and nutrient digestibility of piglets reared under optimal or poor hygienic conditions

Two experiments were conducted to estimate the standardized ileal digestible (SID) Trp:Lys ratio requirement for growth performance of nursery pigs. Experimental diets were formulated to ensure that lysine was the second limiting AA throughout the experiments. In Exp. 1 (6 to 10 kg BW), 255 nursery pigs (PIC 327 × 1050, initially 6.3 ± 0.15 kg, mean ± SD) arranged in pens of 6 or 7 pigs were blocked by pen weight and assigned to experimental diets (7 pens/diet) consisting of SID Trp:Lys ratios of 14.7%, 16.5%, 18.4%, 20.3%, 22.1%, and 24.0% for 14 d with 1.30% SID Lys. In Exp. 2 (11 to 20 kg BW), 1,088 pigs (PIC 337 × 1050, initially 11.2 kg ± 1.35 BW, mean ± SD) arranged in pens of 24 to 27 pigs were blocked by average pig weight and assigned to experimental diets (6 pens/diet) consisting of SID Trp:Lys ratios of 14.5%, 16.5%, 18.0%, 19.5%, 21.0%, 22.5%, and 24.5% for 21 d with 30% dried distillers grains with solubles and 0.97% SID Lys. Each experiment was analyzed using general linear mixed models with heterogeneous residual variances. Competing heteroskedastic models included broken-line linear (BLL), broken-line quadratic (BLQ), and quadratic polynomial (QP). For each response, the best-fitting model was selected using Bayesian information criterion. In Exp. 1 (6 to 10 kg BW), increasing SID Trp:Lys ratio linearly increased (P 24.0%]) SID Trp:Lys ratio. For G:F, the best-fitting model was a BLL in which the maximum G:F was estimated at 20.4% (95% CI: [14.3%, 26.5%]) SID Trp:Lys. In Exp. 2 (11 to 20 kg BW), increasing SID Trp:Lys ratio increased (P < 0.05) ADG and G:F in a quadratic manner. For ADG, the best-fitting model was a QP in which the maximum ADG was estimated at 21.2% (95% CI: [20.5%, 21.9%]) SID Trp:Lys. For G:F, BLL and BLQ models had comparable fit and estimated SID Trp:Lys requirements at 16.6% (95% CI: [16.0%, 17.3%]) and 17.1% (95% CI: [16.6%, 17.7%]), respectively. In conclusion, the estimated SID Trp:Lys requirement in Exp. 1 ranged from 20.4% for maximum G:F to 23.9% for maximum ADG, whereas in Exp. 2 it ranged from 16.6% for maximum G:F to 21.2% for maximum ADG. These results suggest that standard NRC (2012) recommendations may underestimate the SID Trp:Lys requirement for nursery pigs from 11 to 20 kg BW

Efecto del sexo y la inclusión de glicerol en el pienso sobre la distribución de ácidos grasos en el triglicérido en ganado porcino

Concentration of C16:0 was higher and C18:1 y C18:2 lower in boars than in gilts in the subcutaneous fat of hams. Dietary inclusion of glycerol decrease C18:2 and PUFA concentration, thus decreasing fat unsaturation. Saturated fatty acids are concentrated in the external position of the triglyceride (Sn-1,3), while PUFA and MUFA are located preferentially in the inner position (Sn-2). No interaction was observed between position and either sex or dietary treatment. The PUFA/SAT index was affected by position, sex and dietary treatment, However, rations in which MUFA were involved were not significant. The C18:0/C18:2 index showed an interaction dietary treatment*position, in which the ratio is increased by dietary glycerol only in the Sn-1,3 position.Los machos castrados tuvieron una concentración más alta de C16:0 y más baja de C18:1 y C18:2 en la grasa subcutánea del jamón. La inclusión de glicerol en el pienso durante la fase de acabado produce una menor concentración de C18:2, del total de PUFA y, en consecuencia, una menor insaturación de la grasa. Los ácidos grasos saturados se concentraron especialmente en las posiciones externas (Sn-1,3), mientras que los MUFA y PUFA lo hicieron preferentemente en la posición central (Sn-2). No se observaron interacciones de la posición de los ácidos grasos individuales debidas al sexo o a la alimentación. La relación PUFA/SAT resultó significativa respecto a la posición, el sexo y la alimentación. Sin embargo, los índices en los que participan los MUFA son mucho más constantes e independientes del sexo y la alimentación. El cociente C18:0/C18:2 muestra una interacción glicerol*posición, de modo que dicho cociente aumenta específicamente en la posición 1,3 cuando los cerdos reciben glicerol, pero no se afecta (o lo hace con muy poca intensidad) en la posición 2

Supersymmetric null-surfaces

Single trace operators with the large R-charge in supersymmetric Yang-Mills theory correspond to the null-surfaces in $AdS_5\times S^5$. We argue that the moduli space of the null-surfaces is the space of contours in the super-Grassmanian parametrizing the complex $(2|2)$-dimensional subspaces of the complex $(4|4)$-dimensional space. The odd coordinates on this super-Grassmanian correspond to the fermionic degrees of freedom of the superstring.Comment: v4: added a reference to the earlier work; corrected the formula for the stabilizer of the BMN vacuum; added the discussion of the complex structure of the odd coordinates in Section 3.

Inclusion of fiber in diets for brown-egg laying pullets: Effects on growth performance and digestive tract traits from hatching to 17 weeks of age

We investigated the effects of fiber inclusion in the diet on growth performance and digestive traits in pullets from hatching to 17 wk of age. The control diets of the 3 feeding periods (0 to 5 wk, 5 to 10 wk, and 10 to 17 wk) were based on corn and soybean meal and did not include any additional fiber source. The experimental diets included 2 or 4% of cereal straw or sugar beet pulp (SBP) at the expense (wt:wt) of the control diet. From 0 to 5 wk of age, fiber inclusion did not affect pullet performance. From hatch to 17 wk of age, the inclusion of straw had little effect on pullet performance but the inclusion of 4% SBP reduced (ADG) (P < 0.05) and reduced feed conversion ratio (FCR; P < 0.001). Pullets fed straw had greater ADG (P < 0.05) and better energy conversion ratio (P < 0.01) than pullets fed SBP. An increase in fiber from 2 to 4% reduced FCR (P < 0.05). Body weight uniformity was not affected by diet. Fiber inclusion increased the relative weight (% BW) of the gizzard at 5 wk (P = 0.056) and 10 wk (P < 0.01) of age, but no differences were detected between fiber sources. At same ages, the relative length (cm/kg BW) of the pullets (P = 0.058 and P < 0.01, respectively) and tarsus (P = 0.079 and P < 0.05, respectively) was higher in pullets fed SBP than in pullets fed straw. Fiber inclusion, however, did not affect any of these traits at 17 wk of age. In summary, the inclusion of 2% straw at the expense (wt:wt) of the whole diet did not affect pullet performance at 17 wk of age. An increase in the level of straw from 2 to 4% reduced FCR but did not affect ADG. The inclusion of SBP, however, reduced pullet growth, with effects being more pronounced at the higher level

Variation among origins in nutrient composition and protein quality of soybean meals

Investigación sobre las variaciones en la composición y en la calidad de las proteinas de la alimentación animal basada en la soja en función de los orígene

Productive performance, carcass and meat quality of intact and castrated gilts slaughtered at 106 or 122 kg BW

A total of 200 (Landrace3Large White dam3Pietrain3Large White sire) gilts of 5063 days of age (23.361.47 kg BW) were used to investigate the effects of castration (intact gilt, IG v. castrated gilt, CG) and slaughter weight (SW; 106 v. 122 kg BW) on productive performance, carcass and meat quality. Four treatments were arranged factorially and five replicates of 10 pigs each per treatment. Half of the gilts were ovariectomized at 58 days of age (8 days after the beginning of the trial at 29.861.64 kg BW), whereas the other half remained intact. The pigs were slaughtered at 106 or 122 kg BW. Meat samples were taken at Musculus longissimus thoracis at the level of the last rib and subcutaneous fat samples were taken at the tail insertion. For the entire experimental period, CG had higher ( P,0.05) BW gain and higher ( P,0.001) backfat and Musculus gluteus medius fat thickness than IG. However, IG had higher ( P,0.05) loin and trimmed primal cut yields than CG. Meat quality was similar for IG and CG but the proportion of linoleic acid in subcutaneous fat was higher ( P,0.001) for IG. Pigs slaughtered at 122 kg BW had higher ( P,0.001) feed intake and poorer feed efficiency than pigs slaughtered at 106 kg BW. An increase in SW improved ( P,0.001) carcass yield but decreased ( P,0.05) trimmed primal cut yield. Meat from pigs slaughtered at the heavier BW was redder (a*; P,0.001) and had more ( P,0.01) intramuscular fat and less thawing ( P,0.05) and cooking ( P,0.10) loss than meat from pigs slaughtered at the lighter BW. In addition, pigs slaughtered at 122 kg BW had less ( P,0.01) linoleic acid content in subcutaneous fat than pigs slaughtered at 106 kg BW. Castration of gilts and slaughtering at heavier BW are useful practices for the production of heavy pigs destined to the dry-cured industry in which a certain amount of fat in the carcass is required. In contrast, when the carcasses are destined to fresh meat production, IG slaughtered at 106 kg BW is a more efficient alternative