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1.
J Appl Anim Welf Sci ; 23(2): 209-218, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-30905178

RESUMEN

The objective of this study was to find a practical means of reducing pain associated with surgical castration by evaluating the effects of oral meloxicam and topical lidocaine, separately and in combination, on behavioral indicators of pain in piglets. Two hundred thirty-five piglets were surgically castrated between three and seven days of age. Immediately following castration, piglets received one of four treatments: (1) No pain mitigation (C; control; n = 58); (2) NSAID only (M; meloxicam; n = 59); (3) Topical anesthetic (L; lidocaine spray; n = 60); or (4) NSAID and topical anesthetic (X; meloxicam and lidocaine spray; n = 59). Behaviors were recorded by direct observation of individual piglets using five-minute scan samples over a five-hour period, for three days post-castration. Results of the experiment demonstrate the administration of oral meloxicam and topical lidocaine spray at the time of castration under the current methods did not mitigate pain associated with the procedure (P = 0.09; C: 2.1 ± 0.1, L: 2.4 ± 0.1, M: 2.1 ± 0.1 and X: 2.1 ± 0.1).


Asunto(s)
Lidocaína/administración & dosificación , Meloxicam/administración & dosificación , Dolor Postoperatorio/veterinaria , Sus scrofa/cirugía , Administración Oral , Administración Tópica , Anestesia Local/veterinaria , Anestésicos Locales/administración & dosificación , Bienestar del Animal , Animales , Animales Recién Nacidos/cirugía , Antiinflamatorios no Esteroideos/administración & dosificación , Masculino , Orquiectomía/veterinaria , Dolor Postoperatorio/prevención & control
2.
Neuropharmacology ; 156: 107396, 2019 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-30366001

RESUMEN

Disproportionate anger and reactive aggression in response to provocation are core symptoms of intermittent-explosive disorder (IED). Previous research shows a link between the propensity for aggression in healthy individuals and altered functioning of prefrontal-limbic and default-mode networks (DMN) at rest when no provocation is present. In a pilot study, we used resting-state functional magnetic resonance imaging to investigate the effects of pronounced reactive aggression in men, exemplified by IED, on the functional organization of resting-state brain networks including subcortical nodes such as the habenula previously implicated in aggression in preclinical models. Graph theory was applied to resting-state networks to determine alterations in global efficiency and clustering in high reactive aggressive men compared to low reactive aggressive men (controls). Further, we computed within-group correlations between trait aggression and graph measures, as well as within-group whole-brain seed-to-voxel regression analyses between trait aggression and habenula resting-state functional connectivity (rsFC). Reactive aggressive men compared to controls showed higher global efficiency in the left habenula, the left pulvinar in the thalamus, the left dorso-lateral prefrontal cortex, and the right temporal pole, as well as a trend for decreased clustering in DMN nodes. In the reactive aggressive group, high levels of trait aggression were linked to lower global efficiency of the left habenula, and to lower rsFC between the left habenula and the left ventro-lateral prefrontal cortex, a core region involved in inhibitory control. Together with preclinical evidence, our findings in men underline the relevance of aberrant habenula-prefrontal connectivity for the severity of aggressive behavior. This article is part of the Special Issue entitled 'Current status of the neurobiology of aggression and impulsivity'.


Asunto(s)
Agresión/fisiología , Habénula/fisiología , Corteza Prefrontal/fisiología , Adulto , Ira/fisiología , Mapeo Encefálico , Trastornos Disruptivos, del Control de Impulso y de la Conducta/fisiopatología , Humanos , Imagen por Resonancia Magnética , Masculino , Vías Nerviosas/fisiología , Proyectos Piloto
3.
J Anim Sci ; 95(3): 1372-1381, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28380534

RESUMEN

The Common Swine Industry Audit (CSIA) was developed and scientifically evaluated through the combined efforts of a task force consisting of university scientists, veterinarians, pork producers, packers, processers, and retail and food service personnel to provide stakeholders throughout the pork chain with a consistent, reliable, and verifiable system to ensure on-farm swine welfare and food safety. The CSIA tool was built from the framework of the Pork Quality Assurance Plus (PQA Plus) site assessment program with the purpose of developing a single, common audit platform for the U.S. swine industry. Twenty-seven key aspects of swine care are captured and evaluated in CSIA and cover the specific focal areas of animal records, animal observations, facilities, and caretakers. Animal-based measures represent approximately 50% of CSIA evaluation criteria and encompass critical failure criteria, including observation of willful acts of abuse and determination of timely euthanasia. Objective, science-based measures of animal well-being parameters (e.g., BCS, lameness, lesions, hernias) are assessed within CSIA using statistically validated sample sizes providing a detection ability of 1% with 95% confidence. The common CSIA platform is used to identify care issues and facilitate continuous improvement in animal care through a validated, repeatable, and feasible animal-based audit process. Task force members provide continual updates to the CSIA tool with a specific focus toward 1) identification and interpretation of appropriate animal-based measures that provide inherent value to pig welfare, 2) establishment of acceptability thresholds for animal-based measures, and 3) interpretation of CSIA data for use and improvement of welfare within the U.S. swine industry.


Asunto(s)
Crianza de Animales Domésticos , Bienestar del Animal/normas , Conducta Animal , Porcinos/fisiología , Animales , Granjas , Estudios de Factibilidad , Carne Roja/normas , Reproducibilidad de los Resultados
4.
J Anim Sci ; 95(11): 4917-4925, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29293700

RESUMEN

Current floor space allowances were determined in research studies conducted 10 to 20 yr ago using pigs that were marketed at a BW of about 113 kg or less. Currently, pork producers are regularly marketing pigs that weigh over 128 kg. Given this precipitous increase in market weight, we conducted 2 experiments to determine if floor space allowances previously determined apply to pigs marketed at greater than 128 kg. Experiment 1 was conducted at 5 university research stations throughout the Upper Midwest region. In this experiment, we evaluated the growth performance, salivary cortisol concentrations, and lesion scores of pigs weighing between 27 and 138 kg provided 0.71, 0.80, 0.89, 0.98, or 1.07 m/pig of floor space. Within each station, group size (range = 6 to 19 pigs) remained constant across floor space treatments but pen size was altered to achieve the desired space allocations. There were 14 replicate pens for each treatment. Overall, increasing floor space allowance increased final BW (linear, = 0.04) and tended (linear, < 0.06) to increase ADG and ADFI. There were no improvements in final BW or ADG beyond 0.89 m/pig. The G:F was not influenced by increasing floor space allocation. Salivary cortisol concentrations and lesion scores were not affected by floor space allowances. Experiment 2 focused on floor space needs of pigs nearing market weight and was conducted at 4 research stations. Pigs weighing about 130 kg were assigned to pens that provided 0.71, 0.80, 0.89, 0.98, or 1.07 m/pig of floor space. Group size ranged from 4 to 11 pigs per pen but was constant across floor space treatments within station. The study lasted 2 wk and there were 8 replicate pens per treatment. As floor space allowance increased, ADG (0.86, 0.95, 0.95, 1.10, and 1.06 kg; linear, < 0.01), ADFI (3.03, 3.26, 3.22, 3.49, and 3.25 kg; quadratic, < 0.05), and final BW (145.6, 145.7, 146.4, 148.3, and 147.9 kg; linear, < 0.01) increased. Based on the results of these 2 experiments, pigs marketed at about 138 kg require at least 0.89 m/pig to support optimal growth performance. However, heavier pigs (about 148 kg) at the end of the finishing period require 0.98 m/pig.


Asunto(s)
Crianza de Animales Domésticos/métodos , Vivienda para Animales , Porcinos/crecimiento & desarrollo , Animales , Peso Corporal , Femenino , Pisos y Cubiertas de Piso , Hidrocortisona/análisis , Distribución Aleatoria , Porcinos/fisiología
5.
J Anim Sci ; 94(11): 4809-4818, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27898938

RESUMEN

Floor space is an important determinant of aggression and stress in group-housed sows, and the aim of the present experiment was to comprehensively examine the effects of floor space in the range of 1.45 to 2.90 m/sow from mixing until 27 d after insemination on aggression, stress, and reproduction of group-housed sows. A previous experiment on the effects of floor space indicated spatial variability across and along the research facility in both sow aggression and stress. To minimize this spatial variability within the research facility, similar-sized pens but with varying groups sizes (10-20) in 4 separate blocks of 3 contiguous pens within each of 9 time replicates (180 sows/replicate) were used to examine 6 space allowances (1.45-2.9 m/sow). Space treatments were appropriately randomized to pens. Although it may be argued that space allowance is confounded with group size in this design, there was no evidence in our previous experiment of group size effects, for pens of 10 to 80 sows, or appreciable interactions between space and group size on aggression, stress, and reproduction. In the present experiment, sows were introduced to treatments within 4 d of insemination and were floor fed 4 times per day (2.5 kg/sow per d). On both Days 2 and 26 after mixing, aggressive behavior (bites and knocks) at feeding and plasma cortisol concentrations were measured. Restricted maximum likelihood mixed model analyses were used to examine the treatment effect after accounting for replicate and random spatial location effects within replicate. There was a consistent linear effect of floor space allowance on aggression at feeding at Day 2 ( < 0.0001) and plasma cortisol concentrations at Day 2 ( = 0.0003), with aggression and stress declining with increasing space. However, there were no effects of space allowance on aggression and stress at Day 26 ( = 0.14 and = 0.79, respectively). These results show that increased floor space in the immediate post-mixing period reduces aggression and stress and that sows may adapt to reduced floor space over time. A strategy of staged-gestation penning, with more space immediately after mixing and less space later in gestation, may address both animal welfare and economic considerations, but this clearly requires further examination.


Asunto(s)
Agresión , Conducta Animal , Vivienda para Animales , Hidrocortisona/sangre , Reproducción , Porcinos/fisiología , Bienestar del Animal , Animales , Femenino , Estrés Fisiológico , Porcinos/sangre
6.
J Dairy Sci ; 98(8): 5280-93, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26004837

RESUMEN

Monitoring in vivo growth of mammary parenchyma (PAR) has historically been difficult, necessitating slaughter studies to measure PAR quantity. Advances in ultrasound (US) technology warrant revisiting its use as a noninvasive tool to monitor PAR growth in vivo. The level of nutrient intake during the first 2mo of life may affect measures of mammary growth and composition. Objectives were to examine the utility of US as an in vivo tool to quantify PAR cross-sectional area in Holstein heifers reared on 1 of 3 diets from birth to 2mo of age, assessing potential dietary effects; assess the relationships between weekly US measurements, teat length, manual palpation of PAR scores, and PAR mass at 2mo of age; and examine mammary composition in experimental animals. Holstein heifers (n=24; 41±1kg of initial body weight) from a single farm were randomly assigned to 1 of 3 milk replacers that differed in source and amount of fat. Milk replacer was fed at 660g of dry matter/d until weaning at 42 d. Heifers had ad libitum access to a common calf starter (20% crude protein) and water for the duration of the 56-d trial. Teat length and palpation scores were obtained weekly. A real-time B-mode US with a 7.5-MHz convex probe was used to examine 2-dimensional PAR area in all 4 glands of heifers once weekly from 2 to 3 d of age to harvest at 56 d. The left front and left rear glands were also examined by US 24h postharvest to validate final US measurements, and then bisected to produce a sagittal plane view of PAR for comparison with US images. Mass and composition of mammary gland tissue were determined at 8 wk using standard methodology. Over the course of this 8-wk trial, average teat length increased from 11 to 17mm. The PAR area started small (6.6±3.2mm(2) per gland) and increased to 42.1±2.5mm(2) per gland by the end of the trial. As anticipated, based on measurements obtained at slaughter, US measurements were more related to amount of PAR (r=0.74) than either teat length (r=0.34) or palpation scoring (r=0.63). Importantly, US is quantitative, whereas palpation scoring is subjective. Diet did not affect mass or composition of PAR in young heifers; total udder PAR mass averaged 1.40±0.80g. In conclusion, we showed that in heifers younger than 2mo of age, obtaining weekly PAR measurements via ultrasound is an effective quantitative tool for measuring changes in PAR area in vivo. Future studies may incorporate and expand upon the methods developed here to determine what quantitative evaluation of PAR in young heifers can reveal about milk production capacity.


Asunto(s)
Dieta/veterinaria , Glándulas Mamarias Animales/diagnóstico por imagen , Glándulas Mamarias Animales/crecimiento & desarrollo , Animales , Peso Corporal , Bovinos , Grasas de la Dieta/análisis , Ingestión de Energía , Femenino , Procesamiento de Imagen Asistido por Computador , Leche/química , Cambios Post Mortem , Ultrasonido , Ultrasonografía , Destete
7.
J Anim Sci ; 92(6): 2402-14, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24753379

RESUMEN

Use of lamb BW or chilled carcass weights (CCW), live-animal ultrasound or direct carcass measurements of backfat thickness (BF; mm) and LM area (LMA; cm(2)), and carcass body wall thickness (BWall; mm) to predict carcass yield and value was evaluated using 512 crossbred lambs produced over 3 yr by mating Columbia, U.S. Meat Animal Research Center Composite, Suffolk, and Texel rams to adult Rambouillet ewes. Lambs were harvested at 3 BW endpoints within each year. The predictive value of 3 to 5 additional linear measurements of live-animal or carcass size and shape was also evaluated. Residual correlations (adjusted for effects of year, breed, and harvest group) between ultrasound and direct measurements were 0.69 for BF and 0.65 for LMA. Increasing ultrasound or carcass LMA had positive effects (P < 0.001) on yield of chilled carcass (i.e., on dressing percentage) and, at comparable CCW, on weight of high-value cuts (rack, loin, leg, and sirloin) before trimming (HVW), weight of trimmed high-value cuts (trimmed rack and loin and trimmed boneless leg and sirloin; TrHVW), and carcass value before (CVal) and after (TrCVal) trimming of high-value cuts. By contrast, ultrasound and direct measures of BF had positive effects on yields of CCW and on HVW and CVal but large negative effects on TrHVW and TrCVal. After adjusting for BW at scanning, increases of 1 mm in ultrasound BF or 1 cm(2) in ultrasound LMA were associated with changes of US$-0.32 (P < 0.10) and $1.62 (P < 0.001), respectively, in TrCVal. Carcass BWall was generally superior to carcass BF as a predictor of TrHVW and TrCVal. Carcass LMA was superior to ultrasound LMA but carcass BF was inferior to ultrasound BF for prediction of carcass yield and value. Increasing LMA thus would be expected to improve carcass yield and value. Addition of linear measurements of live-animal or carcass size and shape to the prediction model reduced residual SD (RSD) for TrHVW and TrCVal by 0.4 to 2.2%, but subsequent removal of ultrasound or direct measures of BF and LMA from the prediction model increased RSD by 7.4 to 12.2%. Measurements of CCW, LMA, BF, and BWall would thus be appropriate to support programs for value-based marketing of lamb carcasses and are superior to systems based only on measurements of size and shape in unribbed carcasses.


Asunto(s)
Composición Corporal/genética , Peso Corporal/genética , Ovinos/anatomía & histología , Ovinos/genética , Animales , Composición Corporal/fisiología , Peso Corporal/fisiología , Cruzamiento , Femenino , Masculino , Ovinos/fisiología
8.
J Anim Sci ; 92(7): 2861-8, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24778326

RESUMEN

Quality measures of lamb longissimus dorsi were evaluated in 514 crossbred wether lambs to assess sire breed differences. Wethers were produced over 3 yr from single-sire matings of 22 Columbia, 22 U.S. Meat Animal Research Center (USMARC)-Composite (Composite), 21 Suffolk, and 17 Texel rams to adult Rambouillet ewes. Lambs were reared to weaning in an extensive western rangeland production system and finished in a feedlot on a high-energy finishing diet. One of three harvest groups were randomly assigned to each lamb, and lambs were transported to The Ohio State University abattoir when the mean BW of wethers remaining in the feedlot reached 54.4, 61.2, or 68.0 kg. After harvest, subjective lean quality scores were assigned and LM pH (immediately after and 24 h after harvest), color (quantified as Minolta L*, a*, and b*), intramuscular fat (IMF), cooking loss percentage, and Warner-Bratzler shear force (WBSF) were determined. Statistical models included fixed effects of sire breed, year of birth, and harvest group and random effects of sire (nested within sire breed and year) and maternal grandsire. Year and harvest group were significant (P < 0.04) for all traits, except harvest group was not for WBSF and lean quality (P > 0.28). At comparable numbers of days on feed, Texel-sired wethers had the greatest (more desirable; P < 0.01) subjective lean quality scores while Composite- and Suffolk-sired lambs were intermediate and Columbia-sired lambs had the lowest (less desirable). Minolta L* values were greater (P < 0.02) for Texel- than Columbia-sired lambs, although this difference is not visually discernible by humans. No significant (P > 0.05) sire breed effects were detected for LM pH at or 24 h after harvest, Minolta a* and b*, IMF, percentage of cooking loss, and WBSF at comparable numbers of days on feed. At comparable chilled carcass weight, significant (P < 0.01) sire breed effects were detected for subjective lean quality score. Texel-sired lambs had greater scores than Columbia- and Suffolk-sired lambs, but Composite-sired lambs did not differ from lambs sired by the other sire breeds. Sire breed effects were not detected (P > 0.15) for LM pH at or 24 h after harvest, Minolta L*, a*, and b*, cooking loss percentage, IMF, and WBSF at comparable chilled carcass weight. Therefore, results of the present study indicated that the 4 sire breeds produced crossbred lamb carcasses that had similar and desirable LM quality measurements, meeting consumer expectations.


Asunto(s)
Músculo Esquelético/anatomía & histología , Ovinos/genética , Adiposidad/genética , Alimentación Animal , Crianza de Animales Domésticos/métodos , Animales , Cruzamiento/métodos , Cruzamiento/normas , Femenino , Calidad de los Alimentos , Masculino , Carne/normas , Carácter Cuantitativo Heredable , Ovinos/anatomía & histología
9.
J Anim Sci ; 92(5): 1980-94, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24663175

RESUMEN

Linear measurements on live lambs and carcasses can be used to characterize sheep breeds and may have value for prediction of carcass yield and value. This study used 512 crossbred lambs produced over 3 yr by mating Columbia, U.S. Meat Animal Research Center (USMARC) Composite, Suffolk, and Texel rams to adult Rambouillet ewes to assess sire-breed differences in live-animal and carcass shape and to evaluate the value of shape measurements as predictors of chilled carcass weight (CCW), weight of high-value cuts (rack, loin, leg, and sirloin; HVW), weight of trimmed high-value cuts (trimmed rack and loin and trimmed, boneless leg and sirloin; TrHVW), and estimated carcass value before (CVal) and after trimming of high-value cuts (TrCVal). Lambs were produced under extensive rangeland conditions, weaned at an average age of 132 d, fed a concentrate diet in a drylot, and harvested in each year in 3 groups at target mean BW of 54, 61, and 68 kg. Canonical discriminant analysis indicated that over 93% of variation among sire breeds was accounted for by the contrast between tall, long, less-thickly muscled breeds with greater BW and CCW (i.e., the Columbia and Suffolk) compared with shorter, more thickly muscled breeds with smaller BW and CCW. After correcting for effects of year, harvest group, sire breed, and shipping BW, linear measurements on live lambs contributed little to prediction of CCW. Similarly, after accounting for effects of CCW, linear measurements on live animals further reduced residual SD (RSD) of dependent variables by 0.2 to 5.7%, with generally positive effects of increasing live leg width and generally negative effects of increasing heart girth. Carcass measurements were somewhat more valuable as predictors of carcass merit. After fitting effects of CCW, additional consideration of carcass shape reduced RSD by 2.1, 3.6, 9.5, and 2.2% for HVW, TrHVW, CVal, and TrCVal, respectively. Effects of increasing carcass leg width were positive for HVW, TrHVW, and TrCVal. We also observed positive effects of increasing carcass length on TrCVal and negative effects of increasing cannon bone length on HVW and CVal. Increasing shoulder width had positive effects on CVal but negative effects on TrHVW. Differences in lamb and carcass shape were significantly associated with carcass yield and value, but the additional accuracy associated with use of these measurements was modest relative to that achieved from use of only shipping BW or CCW.


Asunto(s)
Cruzamiento , Cruzamientos Genéticos , Ovinos/genética , Ovinos/fisiología , Animales , Femenino , Masculino
10.
J Anim Sci ; 91(12): 5680-6, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24249799

RESUMEN

The dietary effects of Cu, Fe, Mn, and Zn levels, and the addition of Zn and Fe to a nonfortified, micromineral basal diet were evaluated in grower-finisher pigs. Growth, feed efficiency, hematology, carcass characteristics, and loin quality were assessed in growing-finishing pigs (n = 222; initial BW = 24 kg). Corn-soybean meal diets fortified with limestone and dicalcium phosphate with added phytase constituted the basal diets. A study was conducted with 6 dietary treatments and 7 replicates in a randomized complete block design. Treatments consisted of: 1) basal diet without added Cu, Fe, Mn, and Zn microminerals, 2) basal + 50% NRC Cu, Fe, Mn, and Zn requirements, 3) basal + 100% NRC Cu, Fe, Mn, and Zn requirements, 4) basal + 25 mg Zn/kg, 5) basal + 50 mg Zn/kg, and 6) basal + 50 mg Fe/kg. The microminerals were added as an organic mineral proteinate and all diets incorporated organic Se at 0.3 mg/kg. Diets were fed ad libitum over 3 growth phases. At 55, 80, and 115 kg BW, 3 pigs per pen were bled and hemoglobin (Hb) and percent hematocrit (Hct) were determined. At 115 kg BW, 3 pigs per pen were killed and carcass characteristics and loin quality measurements were determined. The ADG, ADFI, and G:F for each of the 3 dietary phases and overall period were not affected by dietary micromineral treatments. The concentration of Hb and percent Hct did not differ because of the treatment at each of the 3 phases. There were no treatment differences in carcass characteristics (HCW, backfat, or LM area). Loin pH, color (L*, a*, and b*), and drip loss did not differ by dietary treatment. Subjective marbling, color, and firmness scores, and intramuscular fat content of loins did not differ as the micromineral level increased above the 1998 and 2012 NRC requirements. The LM from pigs fed supplemental Fe had greater (P < 0.05) firmness and wetness scores than pigs fed the basal diet. These results indicate that there is sufficient amount of innate microminerals (Cu, Fe, Mn, and Zn) in a typical corn-soybean meal based diet to meet the grower-finisher pig's requirement for growth and hematological measurements. Although there was no detrimental effect by eliminating these microminerals from diets, it would seem that a dietary level of 50% of the NRC requirement for Cu, Fe, Mn, and Zn would be warranted.


Asunto(s)
Alimentación Animal/análisis , Minerales/farmacología , Porcinos/crecimiento & desarrollo , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Composición Corporal , Cobre/química , Cobre/farmacología , Dieta , Hierro/química , Hierro/farmacología , Manganeso/química , Manganeso/farmacología , Carne/normas , Minerales/química , National Academy of Sciences, U.S. , Necesidades Nutricionales , Estados Unidos , Zinc/química , Zinc/farmacología
11.
J Anim Sci ; 91(10): 4936-44, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23942715

RESUMEN

The present study was conducted as a 3 × 2 factorial experiment in 7 pen replications conducted using progeny (n = 360) of successive farrowings of 1 Landrace breeding female population. Grower-finisher dietary treatments included the addition of Bio-Mos (BM; at 0.2, 0.1 and 0.05% inclusion rates for phase 1 (30.2 to 63.5 kg), 2 (63.5 to 90.5 kg), and 3 (90.5 to 113.6 kg), respectively), the inclusion of a subtherapeutic antibiotic (AB; tetracycline; at 0.0055% inclusion rate in all dietary phases) and a no additive control (CON) diet. Housing systems were a conventional, indoor (IN) facility providing 1.0 m(2)/pig solid concrete and 0.3 m(2)/pig slatted floor with 12 pigs per pen and an outdoor access (OUT) system providing 1.1 m(2)/pig indoor, bedded concrete, and 1.9 m(2)/pig outdoor solid concrete with 6 pigs per pen. Housing systems analyses acknowledge confounding of space with number of pigs per pen. Daily growth rate (ADG), feed intake (ADFI), feed conversion (G:F), ultrasonic carcass composition, blood hematocrit (1 group), and observed illnesses were measured. Dietary × housing treatment interactions were not observed. Pigs reared in OUT had greater ADFI (0.1 kg/d; P = 0.01) resulting in greater ADG (0.04 kg/d; P < 0.0005) and required fewer days to reach a standard 113.6 kg endpoint (4.0 d; P < 0.0005) but had reduced (poorer) G:F (0.01 kg gain/kg feed; P = 0.05) when compared to IN. Pigs fed BM and CON diets had greater ADG (0.02 kg/d; P < 0.05) and required 3 fewer days to 113.6 kg (P < 0.05) when compared with pigs fed AB. Carcass composition measures were not different across dietary or housing treatments. Hematocrit was 2 units greater (P < 0.05) at the end of the trial (d 84) for OUT housed pigs but not different at the start, d 28, or d 56 of the trial. In the present study, the addition of a subtherapeutic antibiotic in swine finisher diets did not improve pig growth, efficiency, or health whereas the addition of BM did not increase growth performance compared to the CON diet in both housing systems, a finding suggesting the potential for improved gut health and or improved appetite in pigs not fed an antibiotic. Whereas pigs reared OUT had greater growth rate and a more desirable hematocrit level, the observed differences may be attributed to stocking density, number of pigs per pen, or outdoor access, effects that are not able to be fully described under the experimental design.


Asunto(s)
Alimentación Animal/análisis , Composición Corporal/fisiología , Vivienda para Animales , Mananos/farmacología , Porcinos/crecimiento & desarrollo , Porcinos/fisiología , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Femenino , Masculino , Mananos/química , Aumento de Peso
12.
J Anim Sci ; 91(9): 4104-15, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23894000

RESUMEN

Reproductive performance of animals affects lifetime productivity. However, improvement of reproductive traits via direct selection is generally slow due to low heritability. Therefore, identification of indicator traits for reproductive performance may enhance genetic response. Previous studies showed that serum IGF-I concentration is a candidate indicator for growth and reproductive traits. The objective of our study was to estimate the variances or covariances of IGF-I concentration with reproductive traits. Data were collected from a divergent selection experiment for serum IGF-I concentration at the Eastern Agricultural Research Station owned by The Ohio State University. The study included a total of 2,662 calves in the 1989 to 2005 calf crops. Variance or covariance components were estimated for direct and maternal genetic effects, maternal environment effects, environment effects, and phenotypic effects using an animal model in a multiple-trait, derivative-free, restricted maximum likelihood (MTDFREML, Boldman et al., 1995) computer program. Direct additive genetic correlations suggest that selection for greater IGF-I concentration (heritability = 0.50 ± 0.07) could lead to increased conception rate (heritability = 0.11 ± 0.06, r = 0.32, P < 0.001) and calving rate (heritability = 0.13 ± 0.06, r = 0.43, P < 0.001) and decreased age at first calving in heifers (heritability = 0.35 ± 0.20, r = -0.40, P < 0.001).


Asunto(s)
Crianza de Animales Domésticos , Bovinos/fisiología , Factor I del Crecimiento Similar a la Insulina/metabolismo , Reproducción , Selección Genética , Animales , Bovinos/genética , Femenino , Fertilización , Tamaño de la Camada , Ohio , Sitios de Carácter Cuantitativo , Radioinmunoensayo/veterinaria , Factores de Tiempo
13.
J Anim Sci ; 91(7): 3429-35, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23658358

RESUMEN

The objective of this investigation was to determine the effect of a reduced nocturnal temperature (RNT) regimen on performance of weaned pigs and energy consumption during the nursery phase of production. The age of weaned pigs assigned to experiments ranged from 16 to 22 d. In Exp. 1, 3 stations conducted 2 trials under a common protocol that provided data from 6 control rooms (CON; 820 pigs) and 6 RNT rooms (818 pigs). Two mirror-image nursery rooms were used at each station. Temperature in the CON room was set to 30°C for the first 7 d, then reduced by 2°C per week through the remainder of the experiment. Room temperature settings were held constant throughout the day and night. The temperature setting in the RNT room was the same as CON during the first 7 d, but beginning on the night of d 7, the room temperature setting was reduced 6°C from the daytime temperature from 1900 to 0700 h. The use of heating fuel and electricity were measured weekly in each room. Overall, ADG (0.43 kg), ADFI (0.62 kg), and G:F (0.69) were identical for CON and RNT rooms. Consumption of heating fuel [9,658 vs. 7,958 British thermal units (Btu)·pig(-1)·d(-1)] and electricity (0.138 vs. 0.125 kilowatt-hour (kWh)·pig(-1)·d(-1)] were not statistically different for CON and RNT rooms, respectively. In Exp. 2, 4 stations conducted at least 2 trials that provided data from 9 CON rooms (2,122 pigs) and 10 RNT rooms (2,176 pigs). Experimental treatments and protocols were the same as Exp. 1, except that the RNT regimen was imposed on the night of d 5 and the targeted nighttime temperature reduction was 8.3°C. Neither final pig BW (21.8 vs. 21.5 kg; SE = 0.64), ADG (0.45 vs. 0.44 kg; SE = 0.016), ADFI (0.61 vs. 0.60 kg; SE = 0.019), nor G:F (0.75 vs. 0.75; SE = 0.012) were different for pigs housed in CON or RNT rooms, respectively. Consumption of heating fuel and electricity was consistently reduced in RNT rooms for all 4 stations. Consumption of heating fuel (10,019 vs. 7,061 Btu·pig(-1)·d(-1); SE = 1,467) and electricity (0.026 vs. 0.021 kWh·pig-1·d-1; SE = 0.004) were lower (P < 0.05) in the RNT rooms compared with CON rooms. This represents a 30% reduction in heating fuel use and a 20% reduction in electrical use with no differences in pig growth performance or health. From these experiments, we conclude that imposing a RNT regimen from 1900 to 0700 h is effective in reducing energy costs in the nursery without compromising pig performance, which will reduce production costs and decrease emissions of greenhouse gases.


Asunto(s)
Crianza de Animales Domésticos/métodos , Conducta Alimentaria , Calefacción/métodos , Sus scrofa/fisiología , Aumento de Peso , Crianza de Animales Domésticos/economía , Animales , Calefacción/economía , Distribución Aleatoria , Sus scrofa/genética , Sus scrofa/crecimiento & desarrollo , Temperatura , Factores de Tiempo
14.
J Anim Sci ; 91(5): 2012-20, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23463555

RESUMEN

Postfabrication carcass component weights of 517 crossbred wether lambs were analyzed to evaluate 4 terminal-sire breeds. Wethers were produced over 3 yr from single-sire matings of 22 Columbia, 22 USMARC-Composite (Composite), 21 Suffolk, and 17 Texel rams to adult Rambouillet ewes. Lambs were reared to weaning in an extensive western rangeland production system and finished in a feedlot on a high-energy finishing diet. When wethers reached a mean BW of 54.4, 61.2, or 68.0 kg, they were transported to The Ohio State University abattoir for harvest. After refrigeration for approximately 24 h, chilled carcass weight (CCW) was measured, carcasses were fabricated according to Style A of Institutional Meat Purchase Specifications, and postfabrication weights were recorded. At comparable numbers of days on feed, Suffolk-sired lambs had heavier (P < 0.04) neck, breast, shoulder, foreshank, rack, loin, leg, sirloin, roast-ready rack, trimmed loin, and boneless leg cuts than progeny of the other sire breeds. Boneless sirloins were heavier (P < 0.01) for Suffolk-sired than Composite-sired lambs but did not differ from those for Columbia- or Texel-sired lambs. Columbia- and Suffolk-sired lambs had heavier (P < 0.01) hindshanks than Texel-sired lambs. Suffolk-sired lambs had heavier (P < 0.01) high-value cuts (rack, loin, leg, and sirloin) and trimmed high-value cuts than progeny of the other sire breeds. Cutting loss (CCW - wholesale cut weights) and high-value trimming loss were greatest (P < 0.02) for Suffolk-sired lambs and least for Texel- and Composite-sired lambs. Sire breed did not affect (P > 0.06) flank weight. Data adjusted to comparable CCW reduced the number of significant sire-breed effects and changed sire-breed rankings of carcass component weights, for which sire breeds differed. After adjusting, Suffolk-sired lambs had lighter (P < 0.05) loins than Columbia- and Composite-sired lambs, Composite-sired lambs had heavier (P < 0.05) high-value cuts than Suffolk-sired lambs, and Suffolk- and Columbia-sired lambs had heavier (P < 0.05) necks than Texel-sired lambs. At predicted backfat thickness of 6.6 mm, Composite-sired lambs had a greater (P < 0.05) percentage of high-value cuts than Suffolk-sired lambs before but not after trimming. Producers can use these results to select terminal-sire breeds that will complement their production system and improve lamb value.


Asunto(s)
Crianza de Animales Domésticos/métodos , Composición Corporal , Ovinos/fisiología , Animales , Peso Corporal , Cruzamientos Genéticos , Masculino , Ohio , Ovinos/genética , Ovinos/crecimiento & desarrollo , Especificidad de la Especie
15.
Transl Psychiatry ; 2: e176, 2012 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-23092980

RESUMEN

Dopamine modulates executive function, including sustaining cognitive control during mental fatigue. Using event-related functional magnetic resonance imaging (fMRI) during the color-word Stroop task, we aimed to model mental fatigue with repeated task exposures in 33 cocaine abusers and 20 healthy controls. During such mental fatigue (indicated by increased errors, and decreased post-error slowing and dorsal anterior cingulate response to error as a function of time-on-task), healthy individuals showed increased activity in the dopaminergic midbrain to error. Cocaine abusers, characterized by disrupted dopamine neurotransmission, showed an opposite pattern of response. This midbrain fMRI activity with repetition was further correlated with objective indices of endogenous motivation in all subjects: a state measure (task reaction time) and a trait measure (dopamine D2 receptor availability in caudate, as revealed by positron emission tomography data collected in a subset of this sample, which directly points to a contribution of dopamine to these results). In a second sample of 14 cocaine abusers and 15 controls, administration of an indirect dopamine agonist, methylphenidate, reversed these midbrain responses in both groups, possibly indicating normalization of response in cocaine abusers because of restoration of dopamine signaling but degradation of response in healthy controls owing to excessive dopamine signaling. Together, these multimodal imaging findings suggest a novel involvement of the dopaminergic midbrain in sustaining motivation during fatigue. This region might provide a useful target for strengthening self-control and/or endogenous motivation in addiction.


Asunto(s)
Encéfalo/metabolismo , Trastornos Relacionados con Cocaína/metabolismo , Trastornos del Conocimiento/metabolismo , Fatiga Mental/metabolismo , Adulto , Encéfalo/efectos de los fármacos , Encéfalo/fisiopatología , Estudios de Casos y Controles , Núcleo Caudado/metabolismo , Núcleo Caudado/fisiopatología , Trastornos Relacionados con Cocaína/complicaciones , Trastornos Relacionados con Cocaína/fisiopatología , Trastornos del Conocimiento/etiología , Trastornos del Conocimiento/fisiopatología , Inhibidores de Captación de Dopamina/farmacología , Función Ejecutiva , Femenino , Neuroimagen Funcional , Giro del Cíngulo/metabolismo , Giro del Cíngulo/fisiopatología , Humanos , Imagen por Resonancia Magnética , Masculino , Fatiga Mental/fisiopatología , Metilfenidato/farmacología , Persona de Mediana Edad , Motivación , Tomografía de Emisión de Positrones , Tiempo de Reacción , Receptores de Dopamina D2/metabolismo , Test de Stroop , Sustancia Negra/metabolismo , Sustancia Negra/fisiopatología , Tegmento Mesencefálico/metabolismo , Tegmento Mesencefálico/fisiopatología , Área Tegmental Ventral/metabolismo , Área Tegmental Ventral/fisiopatología
16.
J Anim Sci ; 90(12): 4346-54, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22829614

RESUMEN

The process of lipolysis is essential for regulating the catabolism of cellular fat stores. Therefore, knowledge of lipolysis contributes to improving porcine production, such as reducing back fat, enhancing lean meat, and controlling marbling. Comparative gene identification-58 (CGI-58) plays an important role in the multi-enzyme-mediated process of lipolysis. It was identified as the co-activator of adipose triglyceride lipase (ATGL), which performs the first step in breaking down triacylglycerol and generating diacylglycerol and NEFA. We cloned and sequenced the CGI-58 cDNA and deduced the AA sequences in 3 breeds of swine (Duroc, Berkshire, and Landrace). Homologies were found with the human, mouse, and chicken for the lipid droplet binding domain, the α/ß hydrolase domain, and the lysophosphatidic acid acyltransferase (LPAAT) domain, which demonstrates conservation of CGI-58 across species. An alternatively spliced isoform with an exon 3 deletion was identified. Interestingly, this unique isoform contains the lipid droplet-binding domain but lacks the LPAAT domain due to an open reading frame (ORF) shift that creates a premature stop codon. Furthermore, porcine CGI-58 is expressed in multiple organs and tissues but is most predominant in adipose tissue. Porcine adipose and stromal-vascular (SV) cell fractionation reveals that CGI-58 and ATGL are highly expressed (P < 0.01) in mature adipocytes. The expressions of both CGI-58 and ATGL mRNA were found to increase (P < 0.05) at d 6 of SV cell culture, confirming their upregulation during adipogenesis and differentiation. Also, the results from in vitro cell culture showed that insulin decreased (P < 0.05) the expressions of both CGI-58 and ATGL in a dose-dependent manner. Overall, these results report the cDNA and AA sequences of porcine CGI-58 with identification of its unique alternatively spliced variant. The results of the study also reveal the developmental and hormonal regulation of porcine CGI-58 gene, which contributes to the understanding of the role of CGI-58 in lipid metabolism. These findings suggest that CGI-58 may be a new target for enhancing the quality of pork products as well as offering the potential of CGI-58 for human obesity treatment.


Asunto(s)
1-Acilglicerol-3-Fosfato O-Aciltransferasa/metabolismo , Regulación del Desarrollo de la Expresión Génica/fisiología , Regulación Enzimológica de la Expresión Génica/fisiología , Porcinos/genética , Porcinos/metabolismo , 1-Acilglicerol-3-Fosfato O-Aciltransferasa/genética , Empalme Alternativo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , Isoenzimas/genética , Isoenzimas/metabolismo , Metabolismo de los Lípidos , Biología Molecular , Datos de Secuencia Molecular , ARN Mensajero/genética , ARN Mensajero/metabolismo
17.
Meat Sci ; 92(4): 511-8, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22688438

RESUMEN

Numerous reports have described genetic markers or genomic regions (QTL) associated with pork quality and/or palatability but few validation studies have been reported. Therefore, 156 SNP markers from 45 candidate genes and eight QTL regions were analyzed for association with pork quality and palatability traits from 888 pork loins. Loins were collected at three slaughter facilities and selected to represent a wide range of pork color, pH and marbling. Phenotypic data recorded included objective and subjective measures of color and marbling, purge loss, shear force, and cooking loss. Data were analyzed with SAS PROC MIXED where loin was fit as a random effect. Results indicated some of the markers tested should be useful in industry, while others are not segregating in all populations or linkage disequilibrium between markers and causative genetic variation fluctuates among populations limiting their universal utility. Genes with the largest effects on pork quality were MC4R, IGF2, CAST and PRKAG3.


Asunto(s)
Proteínas Quinasas Activadas por AMP/genética , Proteínas de Unión al Calcio/genética , Calidad de los Alimentos , Carne/análisis , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Sus scrofa/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Biomarcadores/metabolismo , Proteínas de Unión al Calcio/metabolismo , Grasas de la Dieta/análisis , Estudios de Asociación Genética/veterinaria , Calor , Concentración de Iones de Hidrógeno , Factor II del Crecimiento Similar a la Insulina/genética , Factor II del Crecimiento Similar a la Insulina/metabolismo , Isoenzimas/genética , Isoenzimas/metabolismo , Desequilibrio de Ligamiento , Pigmentación , Receptor de Melanocortina Tipo 4/genética , Receptor de Melanocortina Tipo 4/metabolismo , Resistencia al Corte , Agua/análisis
18.
J Anim Sci ; 90(9): 2953-62, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22408088

RESUMEN

To evaluate terminal-sire breeds, harvest BW, prefabrication carcass measurements, and organ weights were evaluated over 3 yr for 518 crossbred wether lambs (ovis aries). Lambs were produced by single-sire matings of 22 Columbia, 22 USMARC-Composite (Composite), 21 Suffolk, and 17 Texel rams to adult Rambouillet ewes. Lambs were raised to weaning under an extensive western rangeland production system and finished in a feedlot on a high-energy finishing diet. Wethers were randomly assigned to be harvested at an average BW of 54.4, 61.2, or 68.0 kg and then transported to The Ohio State University abattoir for harvest. Wether BW was recorded before transport (off-test BW) and before harvest. Prefabrication carcass measurements and organ weights were recorded either after harvest or after an approximate 24-h chill. At comparable numbers of days on feed, Suffolk-sired lambs had heavier (P < 0.01) off-test BW, harvest BW, HCW, chilled carcass weight (CCW), and kidney weights than lambs sired by the other breeds. Suffolk-sired lambs had more (P < 0.01) kidney-pelvic fat than did Columbia-sired lambs; Composite- and Texel-sired lambs were intermediate and did not differ (P > 0.06) from the other crossbred lambs. Texel- and suffolk-sired lambs had larger lm area and greater conformation scores than Columbia-sired lambs (P < 0.03). Texel-sired lambs had greater (P < 0.01) body wall thickness, quality grades, and leg scores than Columbia-sired lambs. Composite- and Suffolk-sired lambs did not differ from each other or from lambs sired by any other breed for body wall thickness (P > 0.18) and were intermediate for quality grades and leg scores. Sire breed did not affect (P > 0.05) shipping shrink, dressing percentage, pelt weight, liver weight, and fat depth. Adjusting data to a comparable off-test BW or CCW modified sire breed rankings for some measurements. Texel-sired lambs were equal or superior to lambs sired by other breeds for HCW, CCW, dressing percentage, pelt weight, LM area, quality grade, and leg and conformation scores. However, Texel-sired lambs also had values for kidney-pelvic fat weight, fat depth, and body wall thickness that were equal to or greater than those of lambs sired by the other breeds, indicating increased fatness at comparable BW. Producers can use these results to select terminal-sire sheep breeds that will complement their production system and improve market lamb value.


Asunto(s)
Crianza de Animales Domésticos/métodos , Composición Corporal/genética , Ovinos/genética , Ovinos/fisiología , Animales , Cruzamiento , Femenino , Fertilidad , Riñón/anatomía & histología , Hígado/anatomía & histología , Masculino , Ovinos/crecimiento & desarrollo , Destete , Aumento de Peso
19.
J Food Prot ; 75(1): 139-43, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22221367

RESUMEN

Campylobacter has been implicated as a major cause of foodborne illness worldwide. Pigs can be subclinically infected, and fecal contamination of meat during slaughter is a food safety risk. The objective of this study was to determine the association between the concentration of Campylobacter pre- and periharvest with postharvest contamination in swine. Samples were collected from 100 individually identified swine during the pre-, peri-, and postharvest periods. For each animal, the following phases were sampled: on farm (fecal sample), in lairage (hide swab), post-stunning and exsanguination (rectal contents), prechilling (carcass swab), and final product (rib meat) sample. The proportions of samples that were Campylobacter positive were 90, 95, 76, 100, and 49% for fecal, rectal content, hide, carcass, and rib meat samples, respectively. The mean Campylobacter concentrations for each sample were fecal sample, 1.7 × 10(6) CFU/g; rectal content, 1.2 × 10(7) CFU/g; hide swab, 1.4 CFU/cm(2); carcass swab, 1.7 × 10(3) CFU per half carcass; and rib meat, 18 CFU/g. There was a positive correlation between Campylobacter concentrations in fecal samples (R = 0.20, P = 0.065) and concentration of Campylobacter on rib meat, and between rectal content sample concentration (R = 0.20, P = 0.068) and the concentration on rib meat. There was no association between the isolation of Campylobacter on rib meat and the isolation of Campylobacter at any pre- or periharvest stage. This could indicate that the risk of a meat product being contaminated is associated with pigs that shed higher concentrations of Campylobacter before slaughter.


Asunto(s)
Mataderos , Campylobacter/aislamiento & purificación , Contaminación de Alimentos/análisis , Carne/microbiología , Animales , Campylobacter/crecimiento & desarrollo , Recuento de Colonia Microbiana , Heces/microbiología , Microbiología de Alimentos , Humanos , Recto/microbiología , Medición de Riesgo , Piel/microbiología , Porcinos
20.
J Anim Sci ; 90(4): 1356-63, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22147466

RESUMEN

The objectives of this study were to determine the effects of 0, 20, 40, or 60% dietary dried distillers grains with solubles (DDGS) on 1) growing lamb performance, carcass characteristics, and tissue minerals, and 2) nutrient digestibility and retention in growing lambs. In Exp. 1, ninety-six lambs were blocked by sex (ewes, n = 48; wethers, n = 48) and BW, housed in 24 pens (4 lambs per pen), and used in a 92-d feedlot trial (initial BW = 26.4 ± 9.3 kg). Lambs were fed 1 of 4 dietary treatments 1) 0% DDGS, 2) 20% DDGS, 3) 40% DDGS, or 4) 60% DDGS. The DDGS replaced primarily corn, and diets were fed as a complete pellet. There was a quadratic effect of DDGS inclusion on ADG; lambs fed the 20% DDGS diet had the greatest (P = 0.04) gains at 0.358 kg/d. This effect on ADG led to a quadratic (P = 0.03) effect of DDGS on final BW. Increasing dietary DDGS did not affect (P > 0.13) DMI and resulted in a linear (P = 0.02) decrease in G:F. In the liver, S increased linearly (P = 0.05), whereas Cu decreased linearly (P < 0.01) with increasing dietary DDGS; other liver minerals were not affected (P > 0.05). Carcass backfat, yield grade, and marbling score were not affected (P > 0.05) by dietary DDGS. In Exp. 2, twenty-four lambs (initial BW = 43.0 ± 4.4 kg) were used in a metabolism study. Lambs were adapted to the same diets described above for 17 d before a 5-d sampling period during which total feces and urine were collected. Apparent digestibility of dietary DM decreased linearly (P < 0.01) with increasing dietary inclusion of DDGS. Digestibility of fat followed a similar pattern, whereas N, S, and P absorption increased linearly (P < 0.03) with increasing dietary DDGS. The digestibility of NDF was not affected (P > 0.05) by dietary treatment. Apparent retentions (as a percentage of intake) of N, K, Mg, Cu, Fe, and Zn were not affected (P > 0.05) by dietary DDGS inclusion, whereas the retention of S and P decreased (P < 0.04). Daily urine output increased linearly (P < 0.01) and urine pH decreased linearly (P < 0.01) with increasing DDGS (urine pH was 7.46, 5.86, 5.52, and 5.32 for treatments 1 to 4, respectively). These data suggest urine is a major route for excretion of acid when high-S diets containing DDGS are fed. Increases in dietary DDGS resulted in decreased digestion of DM and fat, which may be partially responsible for decreased lamb feedlot performance for 40 and 60% dietary DDGS when compared with 20% DDGS.


Asunto(s)
Digestión/fisiología , Grano Comestible/metabolismo , Carne/normas , Ovinos/crecimiento & desarrollo , Animales , Animales Recién Nacidos/anatomía & histología , Animales Recién Nacidos/fisiología , Dieta/veterinaria , Femenino , Técnicas In Vitro , Ovinos/fisiología , Zea mays/metabolismo
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