Search

El objetivo fue comparar el efecto de la castración quirúrgica al nacimiento vs immunocastración, sobre las características de la canal y carne en machos Holstein en engorda; se utilizaron 720 machos Holstein aproximadamente de 7 a 8 meses de edad con peso inicial de 240.82 kg. Se formaron 2 tratamientos con 4 corrales de 90 animales en cada uno: toros castrados quirúrgicamente que fueron castrados 24 h después del nacimiento y toros inmunocastrados vacunados con Bopriva aplicando cuatro dosis, al día 1, 21, 101 y 181 de engorda. Se tomaron pesos individuales en cada vacunación. Los animales se sacrificaron a los 242 días de engorda. A partir de la segunda vacunación se observaron diferencias (P0.05) entre tratamientos mientras que los valores de b*, C* y H* fueron más altos (P

Forty-eight Pelibuey × Katahdin (27.87±4.71 kg) intact lambs were used in a growth-performance trial lasted 87 days to assess the effects of treatments. Lambs were assigned to one of six weight groupings in 24 pens (6 replicas per treatment). Basal diet was comprised by cracked corn (14% CP and 2.08 Mcal ENm/kg) and was supplemented as follows: 1) No additives (Control); 2) supplemented with a blend of essential oils at dose of 150 mg EO/kg diet DM (EO, CRINA® Ruminants, DSM Nutritional Products); 3) supplemented with 150 mg EO plus 560 mg alpha-amylase/kg diet DM (EO+ENZ, RONOZYME® Rumistar, DSM Nutritional Products), and 4) supplemented with antibiotic virginiamycin (VM, Stafac 500, Phibro Animal Health) at dose of 28 mg virginiamycin/kg diet DM. Growth performance and dietary energetics were very similar (P > 0.97) between EO and VM. In such way that, compared to Control, lambs supplemented with EO and VM tended (P = 0.09) to shown greater final weight (3.1%) and average daily gain (ADG; 5.9%) without difference on DMI (P = 0.99); thus, gain-to-feed ratio (GF) and observed dietary net energy (NE) were average improved in 5.7% (P < 0.01). Compared to Controls, combining EO plus ENZ tended to increased DMI (6.8%, P = 0.09), but increased in 10.4% ADG (P < 0.01) and in 4.4% (P = 0.02) feed efficiency. Lambs supplemented with EO shown lower (P ≤ 0.10) kidney-pelvic-heart fat than Controls and VM lambs. Compared to Controls, additive supplementation decreased (P ≤ 0.03) the relative weight of intestines, the effect being more pronounced with EO supplementation. Compared to VM, supplemental EO (alone or combined with enzyme) shown lower (10.1%, P ≤ 0.04) visceral fat. Supplemental essential oils is a viable alternative to virginiamycin in finishing high-energy diets for lambs. Combining essential oils plus amylase can be a strategy to promote better daily gain weights allowing target final weight at shorter time.

Objective: The objective of this experiment was to evaluate the effect of shade allocation and shade plus fan on growth performance, dietary energy utilization and carcass characteristics of feedlot cattle under tropical ambient conditionsMethods: Two trials were conducted, involving a total of 1,560 young bulls (289±22 kg BW) assigned to 24 pens (65 bulls/pen and 6 pens/treatment). Pens were 585 m2 with 15 m fence line feed bunks. Shade treatments (m2 shade/animal) were: i) limited shade (LS) to 1.2 m2shade/animal (LS1.2); ii) limited shade to 2.4 m2 shade/animal (LS2.4); iii) total shade (TS) which correspond to 9 m2/animal, and iv) total shade equipped with fans (TS+F). Trials lasted 158 and 183 days. In both studies, the average weekly maximum temperature exceeded 34°C.Results: Increasing shade allocation tended (p = 0.08) to linearly increases average daily gain (ADG), and dry matter intake (DMI, quadratic effect, p = 0.03). This effect was most apparent between LS1.2 and LS2.4. Shade allocation, per se, did not affect gain efficiency or estimated dietary net energy (NE). Compared with TS, TS+F increased (plongissimus area and marbling score, with values being lower (p2.4 than for LS1.2 or TS. Likewise, marbling score was lower for TS+F than for TS. Percentage kidney, pelvic, and heart (KPH) linearly decreased with increasing shade. In contrast, KPH was greater for TS than for TS+F.Conclusion: Providing more than 2.4 m2 shade/animal will not further enhance feedlot performance. The use of fans in combination with shade increases ADG and gain efficiency beyond that of shade, alone. These enhancements were not associated with increased DMI, but rather, to an amelioration of ambient temperature humidity index on maintenance energy requirement.

El objetivo fue predecir mediante ultrasonografía las características de la canal de 28 ovejas Pelibuey (41.01 ± 8.43 kg) de desecho alimentadas en sistema intensivo, clínicamente sanas, no gestantes y no lactantes. Las mediciones ultrasónicas de espesor de grasa dorsal (EGD), área, (ALD), profundidad (PLD) y ancho (ALD) del músculo Longissimus dorsi, entre la 12.a y 13.a vertebra torácica y entre la 3.a y 4.a vértebra lumbar, se realizaron 24 h antes del sacrificio. Al sacrificio se pesó la canal caliente, así como los órganos internos y la grasa interna. Las canales se dividieron a la mitad, se refrigeraron (1°C; 24 h) y se pesaron en canal frío. Luego fueron diseccionadas y pesadas en sus principales componentes. Con los datos se calcularon los coeficientes de correlación entre variables y las relaciones se estimaron mediante modelos de regresión. Se observó que las mediciones ultrasónicas de grasa dorsal, torácica y lumbar tuvieron un r2 positiva de entre 0.51 y 0.66 (P

Author(s): Rivera-Villegas, A; Estrada-Angulo, A; Castro-Perez, BI; Urias-Estrada, JD; Rios-Rincon, FG; Rodriguez-Cordero, D; Barreras, A; Plascencia, A; Gonzalez-Vizcarra, VM; Sosa-Gordillo, JF; Zinn, RA | Abstract: ObjectiveWe compare the effects of three different approved sources of supplemental zilpaterol on growth-performance responses and carcass characteristics of finishing lambs.MethodsTwenty four Pelibuey×Katahdin lambs (46.75±2.43 kg) were used in a 33-day feeding trial. Lambs were fed a dry rolled corn-based finishing diet. Treatments consisted of the non-supplemental basal diet (Control) versus the basal diet supplemented with 125 mg zilpaterol/kg of diet (as fed basis) from three commercial sources marketed in Mexico: Zilmax (ZIL), Grofactor, and Zipamix.ResultsCompared to controls, zilpaterol (ZH) supplementation did not affect dry matter intake (DMI), but increased carcass adjusted daily weight gain (ADG, 36.7%), gain efficiency (34.2%), and dietary net energy (26.0%), and decreased (23.4%) the ratio of observed:expected DMI. Compared to controls, supplemental ZH increased hot carcass weight (6.4%), dressing percentage (3.2%), m. longissimus thoracis (LM) area (15.6%), and shoulder muscle:fat ratio (28.7%), but decreased kidney-pelvic-heart fat, and fat thickness. Supplemental ZH increased 10.9% and 14.3% whole cut weight of loin and leg, respectively, and the proportion (as percentage of cold carcass weight) of leg (4.3%). These increases were reflected in greater forequarter and hindquarter weights. Lambs fed ZH increased (4.6%) empty body weight (EBW) and reduced (14.7%) liver/spleen weight (as g/kg EBW). Likewise, ZH supplementation tended (p = 0.08) to lower (8.9%) visceral fat. Growth performance, energetic efficiency, hot carcass weight, dressing percentage, LM area and whole cuts were not different across supplemental ZH sources. However, compared with non-supplemented controls, only ZIL appreciably decreased carcass fat distribution, including fat thickness, percentage kidney pelvic and heart fat, shoulder fat, and visceral fat.ConclusionSupplemental ZH increases ADG, gain efficiency, carcass dressing percentage, and LM area. The magnitude of these responses was similar among ZH sources. Nevertheless, compared with non-supplemented controls, only ZIL appreciably decreases carcass fat. The basis for this is uncertain, but indicative that some practical differences in zilpaterol bio-equivalency may exist across commercial sources tested.

A total of 90 young crossbreed bulls (initial weight=228.04±7.06 kg) were used in a 171-day feeding trial in order to evaluate the combination of supplemental blend of essential oils (Crina® Ruminants; DSM Nutritional Products) plus 25-hydroxy-vitamin-D3 (HyD®, DSM Nutritional Products; EO+HyD) on growth performance and carcass characteristics in cattle finishing under tropical conditions. Cattle were blocked by weight into 2 blocks and randomly allocated to 2 treatments (9 pens/treatment, 5 bulls/pen). Cattle were fed with a steam-flaked corn-based diets (average diet NEm= 1.95 Mcal/kg during first 84-d, and 2.15 Mcal/kg during the remaining 87-d). Treatments consisted of: 1) EO+HyD supplementation along fattening period (171-d), or 2) supplementation with monensin (Rumensin®, Elanco Animal Health; 20 mg/kg diet) during the first 84-d and monensin (20 mg/kg diet) plus virginiamycin (Stafac®, Phibro Animal Health; 20 mg/kg diet) during remaining time (87-d). The average THI during course of the experiment was 76.67±2.7 with a maximum of 85.46±2.2 and minimum of 68.29±2.6. There were no statistical differences (P > 0.10) between EO+HyD and ionophores/antibiotic supplemented cattle on DM intake (7.575 vs 7.534 kg/d), average daily gain (1.433 vs 1.406 kg), or gain-to-feed ratio (0.189 vs 0.187). However, cattle fed with EO+HyD tended (P = 0.07) to have heavier carcass weight in 5.2 kg (304.9 vs 299.7 kg), showed greater LM area (89.89 vs. 82.77 cm², P < 0.01) and greater estimated retail yield (1.6%, P = 0.02) than cattle receiving ionophores/antibiotic mixture. Cattle receiving EO+HyD showed more percentage of carcass classified as Choice (14.28 vs 13.33%) and “Select” (59.52 vs 44.44%) and lower percentage of carcass classified as “Standard” (26.20 vs 42.23%). The combination of a blend of essential oils plus 25-hydroxy-Vit-D3 (EO+HyD) in finishing phase improve carcass characteristics. Supplemental EO+HyD is a viable alternative to supplemental monensin, or monensin plus virginiamycin used in growing-finishing diets for feedlot cattle.

Objetivo: Revisar distintos factores relacionados con el transporte de ganado bovino asociados a los indicadores de bienestar. Aproximación: Durante el transporte los bovinos son sometidos a factores desencadenantes de estrés que incluyen: i) incremento del manejo, ii) mezcla de animales de diferente procedencia y contacto con personal extraño, iii) desafíos físicos como rampas, superficies resbaladizas, densidad de carga, movimiento, ruido y vibración del vehículo; iv) contacto con ambientes nuevos y no familiares; v) privación de alimento y agua; vi) cambios en la estructura social, vii) cambios en las condiciones climáticas como temperatura, radiación y humedad, viii) imposibilidad de descanso, entre otros aspectos. En este documento se revisan los efectos del transporte en los indicadores de bienestar del ganado bovino y los efectos de la temperatura, la densidad de carga, duración del viaje, provisión de descanso, agua y alimento entre otros.

La carne de codorniz japonesa (Coturnix coturnix japonica) se destina al consumo humano, por ello es importante mantener su calidad durante el almacenamiento. El objetivo fue evaluar la capacidad de la harina de Pleurotus ostreatus incluida en la dieta, para incrementar la actividad antioxidante total (AAT) de la carne. Para ello, se determinó el contenido de fenoles (CFT) y flavonoides totales (CFVT), así como actividad antiradical-DPPH• y ABTS•+, y poder reductor (PR) del extracto-acuoso de P. ostreatus (EAPO). Las codornices fueron alimentadas durante 35 días con tres dietas: control y suplementadas con P. ostreatus (1 y 2 %). La pechuga (Pectoralis major) se almacenó (10 días/2 °C/oscuridad) y se obtuvo un extracto-acuoso cárnico (EAC) para determinar la AAT. Los resultados mostraron que el EAPO presentó buen CFT y CFVT (27.3 mg EAG/g, y 16.1 mg EQc/g, respectivamente), así como 35 y 49.1 % de actividad antiradical-ABTS•+ y DPPH•, y 35 % de PR. El EAC, presentó valores de CFT, ABTS•+ y DPPH•, superiores al control (P≤0.05), no detectándose diferencias para el CFVT y PR (P≥0.05). En conclusión, la incorporación de P. ostreatus en la dieta de codorniz, incrementó la AAT del EAC durante su almacenamiento.

Forty Pelibuey × Katahdin intact male lambs (23.0 ± 1.8 kg initial shrunk weight) were used in an 84-day feeding trial (5 pens per treatment, randomized complete block design) to evaluate crude protein level (110, 140, 170, and 200 g/kg diet DM) in isocaloric diets (2.03 Mcal NEm/kg) on finishing-phase growth performance, dietary energetics and carcass traits. Increases in protein levels were accomplished by increasing levels of canola and meat meal. Tallow was used to equilibrate energy levels among diets. Increasing dietary protein level increased (linear effect, P = 0.01) 84-d average daily gain, dry matter intake (linear effect, P = 0.03), and gain efficiency (linear effect, P

Simple Summary Concern about the use of antimicrobial compounds in livestock production has promoted research of “generally recognized as safe” additive alternatives. Probiotics (living microorganisms) and prebiotics (certain type of carbohydrates derived from yeast) have been shown to alleviate the negative effects of stress and boost immunity, thereby enhancing efficiency of energy utilization. In some regions (i.e., tropical and arid zones), livestock experience adverse climatic conditions, including elevated ambient temperature and humidity, which affect their productivity. Supplementation with probiotics and prebiotics may help to alleviate these adverse effects. In the present study, supplemental probiotics or/and prebiotics improved dietary energetic efficiency in lambs finished under subtropical climatic conditions. The combination of probiotics with prebiotics reinforced this positive effect. Abstract The aim of this trial was to test the effects of the use of eubiotics (pro- and prebiotics) alone or in combination in the diet of lambs finished under subtropical climate conditions. For this purpose, 40 Pelibuey × Katahdin lambs (29.5 ± 4.8 kg initial live weight) were used in a 93 day growth-performance experiment. Dietary treatments consisted of a cracked corn-based finishing diet supplemented with (1) no eubiotics (control), (2) 3 g of probiotics (live Saccharomyces cerevisiae, SC), (3) 3 g of prebiotics (mannan oligosaccharide plus b-glucans, MOS), and (4) a combination of 1.5 g of SC and 1.5 g of MOS (SC+MOS). Throughout the study, the average temperature humidity index (THI) was 78.60. Compared to controls, supplementation with SC or MOS, alone did not affect average daily gain (ADG), but enhanced feed efficiency by 5.6% and 6.9% (gain-to-feed ratio, G:F) and dietary net energy by 4.6% and 5.9%, respectively. Compared to controls, SC+MOS enhanced ADG (10%), G:F (9.5%), and dietary net energy (7.2%). Lambs fed SC+MOS had also greater ADG, G:F, and dietary net energy compared to lambs fed SC alone. When compared to MOS, the combination enhanced ADG (10.4%, p = 0.04). This effect could be attributed to the increased dry matter intake (7.6%, p = 0.06), as neither G:F nor dietary energy was significantly affected. Compared with controls and SC, supplementation with MOS alone and SC+MOS increased kidney–pelvic–heart fat, while SC supplementation tended (p = 0.08) to reduce 4.1% the relative intestinal mass (as a proportion of empty body weight) when compared to controls. Treatment effects on the other carcass measures were not significant. In the present study, supplemental probiotics and/or prebiotics improved dietary energetic efficiency in lambs finished under subtropical climatic conditions. The combination of probiotics with prebiotics reinforced this positive effect.

Pleurotus ostreatus is an edible mushroom that possesses antioxidant potential. The effect of dietary supplementation with Pleurotus ostreatus on performance, carcass, and meat quality attributes of Japanese quail was investigated. The experiment involving a total of 288 quails 1-d-old, which were fed diets supplemented with P. ostreatus (0, 10 or 20 g/kg of diet) for 35 d, with feed and water for ad libitum consumption. Total polysaccharide (TP), total phenolic and flavonoid content (TPC and TFC), antiradical DPPH• and ABTS•+ activity, as well as polyphenols compositions of P. ostreatus extract were evaluated using high-performance liquid chromatography (HPLC). The pH, color (L*, a* and b*), water holding capacity (WHC), cooking loss weight (CLW), texture and oxidative stability (thiobarbituric acid reactive substances, TBARS; total phenolic content, TPC; antiradical DPPH• and ABTS•+ activity) were measured in breast meat during storage (0, 5, 10 and 15 d; 4 °C without illumination). Statistical differences were not detected on growth performance expressed as body weight gain 228.3 g, feed intake 467.9 g, feed conversion ratio 2.0, feed efficiency 0.49, live weight at the slaughter of the birds 217.2 g, as well as carcass weight 133.0 g and yield 61.3 g of the quail breast (P > 0.05). At day 15 of meat storage, the pH24 (9.0%), a* (14.7%), b* (9.3%), WHC (7.2%), TPC (40.0%), DPPH• (11.0%) and ABTS•+ (33.0%) values were increased in quails fed with P. ostreatus in comparison with the control group; while parameter L* (9.0%), CLW (21.4%), texture (30.7%) and lipid oxidation-TBARS (33.5%) values were reduced (P

To evaluate the effect of immunocastration on carcass and meat characteristics, Holstein bulls aged between 7 and 8months with a live weight of 232±1.19kg were given two separate treatments, placebo (intact bulls) versus Bopriva, and then slaughtered after approximately 239days of fattening. While the testosterone levels in intact bulls remained at 0.42ng/ml throughout the study, by day 181, differences (P0.05) were observed in immunized bulls, with values of 0.21ng/ml. The carcasses of animals treated with Bopriva recorded both a higher hot carcass weight (HCW) and a cold carcass weight (CCW), as well as higher dorsal fat density, marbling and KPH (P0.05); however, no differences (P0.05) were observed in the Longissimus lumborum area. No significant differences (P0.05) were recorded between the treatments for pH, L*, a*, b* C* and H*. The carcasses of the animals treated with Bopriva were heavier, with higher dorsal fat density and marbling score.

Twenty six Katahdin ewes (i.e., female lambs from breeding to 2 mo of their 1st lactation) were used in a completely randomized design (13/treatment) to evaluate effects of replacement of dietary dry-rolled corn grain (DRC) and cottonseed meal (CSM) with hydroponically grown whole plant green wheat (HGW; Triticum aestivum L.) on productive parameters and blood metabolites during mating, gestation and lactation, and on body weight (BW) gain of their lambs in their 1st 60 days of age. The gestation diet contained 70% oat hay, 20% rolled corn grain and 10% cottonseed meal, while the lactation diet contained 50% oat hay, 20% DRC and 30% CSM. Treatments consisted of total replacement of DRC and CSM with HGW in the gestation diet, while in the lactation diet HGW replaced 100% of the DRC and 33% of the CSM. There were no diet effects on reproductive parameters, and substitution of DRC and CSM with HGW did not affect dry matter intake during gestation and lactation. The BW gain of the lambs that were fed HGW did not differ from controls in the first 2 months of gestation, while it was lower ( P 0.05) at the last 3 months of gestation. Feeding HGW did not affect birth BW of lambs or subsequent BW gains through 60 days of age. Plasma non-esterified fatty acids (NEFA) were not affected by the diets fed during gestation, but were 56% lower ( P 0.05) at day 60 of lactation. Plasma glucose was only lower ( P 0.05) at day 90 of gestation, and blood urea nitrogen was only lower ( P 0.05) at day 30 of lactation. There were no effects of diets on plasma insulin, cortisol or progesterone during gestation and lactation. Hydroponically grown green wheat is a suitable substitute for a portion of the DRC and CSM in ewes diets during gestation and lactation without negative effects.

The modification of the natural environment in beef production can induce behavioral changes in cattle. In order to assess the behavioral response based on indicators of animal welfare of beef cattle in feedlot in warm desert environmental conditions; a prospective observational study was conducted with a duration of four weeks. Behavioral guidelines, environmental temperature, relative humidity and temperature and humidity index (THI), were recorded at 8:00 h, 12:00 h, and 16:00 h. Environmental temperature, relative humidity and THI average was 28.7 °C, 24.1 %, and 72.8 units, respectively. During observational period, the beef cattle to be subject at comfort condition (THI≤74). By environmental effect at 12:00 h the usual indicators: eating and drinking, are inhibited (P≤0.01), and grooming decreased (8.2 vs. 13.2 x 100; P≤0.01) Agonist indicators: mounts, threats, Flehmen sign and bumps decrease significantly at 12:00 h (P≤0.01), when the ITH value is greater than 75 units. The highest panting rate (25 x 10000) was observed at 12:00. The diurnal behavioral response of cattle in feedlot on warm desert climate is due to biological rhythms to adapt to the environment that ensures their survival.

o evaluate the effect thatimmunocastrationhas on behaviour, testosterone and cortisol levels of feedlot Holstein bulls, 720 intact animals aged between 7 and 8 months, weighing 232±1.19 kg were randomly assigned to two treatments:immunocastrationusing the Bopriva vaccine and a placebo (360 animals per treatment). The bulls were slaughtered at day 239 of treatment. Animals were vaccinated on days 1, 21, 101, and 181, and on those same days testosterone levels were measured; while cortisol, glucose andcreatinkinase measurements were done on day 181 and duringexanguinationat slaughter. Sexual, aggressive and social behaviours were evaluated and it was found that intact bulls showed a higher average ofhead butts, mounting, threats, flehmen sign and sniffing (P0.05). Testosterone levels in intact bulls remained at 0.47ng/mL throughout the study, however, by day 181 differences (P, To evaluate the effect that immunocastration has on behaviour, testosterone and cortisol levels of feedlot Holstein bulls, 720 intact animals aged between 7 and 8 months, weighing 232±1.19 kg were randomly assigned to two treatments: immunocastration using the Bopriva vaccine and a placebo (360 animals per treatment). The bulls were slaughtered at day 239 of treatment. Animals were vaccinated on days 1, 21, 101, and 181, and on those same days testosterone levels were measured; while cortisol, glucose and creatin kinase measurements were done on day 181 and during exanguination at slaughter. Sexual, aggressive and social behaviours were evaluated and it was found that intact bulls showed a higher average of head butts, mounting, threats, flehmen sign and sniffing (P0.05). Testosterone levels in intact bulls remained at 0.47ng/mL throughout the study, however, by day 181 differences (P

Nueve híbridos de sorgo (Sorghum bicolor L. Moench) se analizaron para determinar la relación de sus características físicas [materia seca (MS), peso de mil granos (PMG), tamaño de partícula (TP), densidad relativa(DR), superficie de área (SA), partículas por gramo (PPG), endospermo duro (END-DU), endospermo blando (ENDBL)]; y químicas [nitrógeno total (NT), fibra detergente ácido (FDA), fibra detergente neutro (FDN), contenido de almidón (ALM), almidón soluble (AlmS), almidón insoluble (AlmNS). La digestión ruminal esperada (DRUM) se estimó con las fracciones de AlmS y AlmNS in vitro. El promedio de PMG, TP, DR, SA, PPG y END-DU fue de 24.61 g, 3.17 mm, 1.30 g/cm3, 17.44 cm2/g, 30.33 y 46.68 %, respectivamente El promedio (%) de MS, PC, FDN, FDA, ALM, AlmS y AlmNS fue de 92.47, 8.19, 19.17 y 8.30, 69.58, 6.00 y 47.74 respectivamente. La concentración de taninos fue baja (0.05) entre las variables físicas o químicas con el contenido total de almidón en el grano; sin embargo las variables densidad relativa y superficie de área, permiten incrementar el poder de predicción de la digestibilidad ruminal del almidón (DRUM,%= 74.058 - 0.108END-DU + 0.027SA – 5.887DR, R2= 0.77, P

Forty-eight Pelibuey×Katahdin male intact lambs (23.87±2.84 kg) were used in an 84-d feeding trial, with six pens per treatment in a 2×2 factorial design arrangement. The aim of the study was to evaluate the interaction of two dietary energy levels (3.05 and 2.83 Mcal/kg ME) and two dietary protein levels (17.5% and 14.5%) on growth performance, dietary energetics and carcass traits. The dietary treatments used were: i) High protein-high energy (HP-HE); ii) High protein-low energy (HP-LE); iii) Low protein-high energy (LP-HE), and iv) Low protein-low energy (LP-LE). With a high-energy level, dry matter intake (DMI) values were 6.1% lower in the low-protein diets, while with low-energy, the DMI values did not differ between the dietary protein levels. Energy levels did not influence the final weight and average daily gain (ADG), but resulted in lower DMI values and higher gain efficiencies. No effects of protein level were detected on growth performance. The observed dietary net energy (NE) ratio and observed DMI were closer than expected in all treatments and were not affected by the different treatments. There was an interaction (p2.80 Mcal/kg ME). Providing a level of protein above 14.5% does not improves growth-performance, dietary energetics or carcass dressing percentage.

Four male lambs (Katahdin; average live weight 25.9±2.9 kg) with "T" type cannulas in the rumen and proximal duodenum were used in a 4×4 Latin square experiment to evaluate the influence of supplemental dry distillers grain with solubles (DDGS) levels (0, 10, 20 and 30%, dry matter basis) in substitution for dry-rolled (DR) corn on characteristics of digestive function and digestible energy (DE) of diet. Treatments did not influence ruminal pH. Substitution of DR corn with DDGS increased ruminal neutral detergent fiber (NDF) digestion (quadratic effect, p

Rios Rincon, F.G., Barreras-Serrano, A., Estrada-Angulo, A., Obregon, J.F., Plascencia-Jorquera, A., Portillo-Loera, J.J. and Zinn, R.A. 2010. Effect of level of dietary zilpaterol hydrochloride (β2-agonist) on performance, carcass characteristics and visceral organ mass in hairy lambs fed all-concentrate diets. J. Appl. Anim. Res., 38: 33–38. To evaluate the influence of zilpaterol (β2-agonist) supplementation level on growth performance, energy retention, carcass characteristics and visceral organ mass lambs were fed a dry-rolled corn-based finishing diet supplemented with 0, 0.12 or 0.18 mg/kg BW d−1 zilpaterol hydrochloride. Zilpaterol supplementation increased carcass adjusted daily gain (40.0%, P

This investigation was carried out to determine the effect of Essential Fatty Acids proportion (EFAs [n-6, n-3]) in feed through the mixture of soy, olive, canola or chia oil on EFA profile in eggs as well as productive and reproductive performance of Japanese quail. We used 120 quail from 7 to 22 weeks of age, in 15 cages in groups of 6 females and 2 males assigned according to the completely randomized design to 3 treatments with 5 replicates. The treatments were n-6:n-3 proportions 10:1 (control), 4:1 and 1:1. FA profile in yolk, feed intake, laying rate, egg weight, fertility, hatchability, and embryonic mortality were measured. In the egg yolk, n-6 content was similar in the proportions (p>0.05), while n-3 content increased (p0.05). In 4:1 and 1:1 proportion laying percentage was greater, but egg weight was lower (p0.68). Early and total embryonic mortality was lower in 10:1 and 4:1 proportion (p0.30). The results of the experiment indicate that the mixture of soy, olive, canola or chia oil, to obtain n-6:n-3 proportion of 1:1, 4:1 and 10:1 does not modify feed consumption, laying rate, egg weight, fertility, and hatchability; but, 4:1 and 10:1 proportions favor a lower embryonic mortality.