RESUMEN
Chediak-Higashi Syndrome (CHS) is a well-characterized, autosomal recessively inherited lysosomal disease caused by mutations in lysosomal trafficking regulator (LYST). The feline model for CHS was originally maintained for ~20 years. However, the colonies were disbanded and the CHS cat model was lost to the research community before the causative mutation was identified. To resurrect the cat model, semen was collected and cryopreserved from a lone, fertile, CHS carrier male. Using cryopreserved semen, laparoscopic oviductal artificial insemination was performed on three queens, two queens produced 11 viable kittens. To identify the causative mutation, a fibroblast cell line, derived from an affected cat from the original colony, was whole genome sequenced. Visual inspection of the sequence data identified a candidate causal variant as a ~20 kb tandem duplication within LYST, spanning exons 30 through to 38 (NM_001290242.1:c.8347-2422_9548 + 1749dup). PCR genotyping of the produced offspring demonstrated three individuals inherited the mutant allele from the CHS carrier male. This study demonstrated the successful use of cryopreservation and assisted reproduction to maintain and resurrect biomedical models and has defined the variant causing Chediak-Higashi syndrome in the domestic cat.
Asunto(s)
Síndrome de Chediak-Higashi/patología , Proteínas de Transporte Vesicular/genética , Alelos , Animales , Gatos , Línea Celular , Síndrome de Chediak-Higashi/genética , Modelos Animales de Enfermedad , Exones , Femenino , Fibroblastos/citología , Fibroblastos/metabolismo , Genotipo , Masculino , Linaje , Polimorfismo Genético , Proteínas de Transporte Vesicular/metabolismoRESUMEN
INTRODUCTION: Outcome-based programmes provide a framework to support educators and learners in understanding content and end points within taught courses. Management of these outcomes in the Dental Degree at Newcastle University has been a challenge in relation to quality assurance and enhancement, having over 1500 detailed student-level outcomes (SLO). This research aimed to explore the implications of adopting a more superficial "course" level of outcome (CLO), when reviewed against a reference set of external LO requirements. MATERIALS AND METHODS: A purposive sample of five courses within the undergraduate dental programme was selected. The mapping of both SLOs and CLOs was reviewed in relation to their total number and the mapping connections to the reference outcomes. RESULTS: There was a mean reduction of 79% in outcomes when comparing SLOs to CLOs. The number of mapping connections between CLOs and the reference set reduced in three courses and increased in two, when compared to SLOs. DISCUSSION: From a purely numerical perspective, changing the detail of learning outcomes has led to a change in mapping connections. As the delivered curriculum has remained unchanged, this demonstrates a potential impact of differing interpretations of learning outcomes. Further review of learning outcomes in relation to the domains categorised within the reference outcome document suggested more mapping links were obtained in clinically focused courses than academic or theoretical courses. CONCLUSION: A demonstrable impact in mapping connections was observed when the detail within the learning outcomes was changed. This has implications for programme leaders in structuring LOs for a curriculum.
Asunto(s)
Éxito Académico , Curriculum , Educación en Odontología/métodos , Competencia Clínica , Educación en Odontología/normas , Evaluación Educacional , Humanos , Aprendizaje , Modelos Educacionales , Estudiantes de Odontología , Reino UnidoRESUMEN
Explicitly-stated learning outcomes are an expected, integral part of contemporary under- and postgraduate learning programmes in dentistry. Writing learning outcomes, however, can be challenging and undertaken with a risk of not understanding what is meant by them and what well-constructed outcomes are meant to do. Written badly, learning outcomes will not help capture the goals of educational interventions or, perhaps worse, they end up as nothing more than a complex, frustrating hoop-jumping exercise in both their conception and utilisation. Underlying misconceptions of the purpose of learning outcomes or how to develop them are likely contributors to this situation. We would argue that if one understands the background, construct and intended purpose of learning outcomes we are more likely to write them so that they can actually be applied and therefore used effectively.
Asunto(s)
Educación en Odontología/métodos , Educación en Odontología/normas , Evaluación Educacional , Humanos , AprendizajeRESUMEN
In response to the Educational Standards of the UK's General Dental Council, Newcastle University, School of Dental Sciences introduced a patient feedback card to gather and incorporate patient feedback into their undergraduate assessment framework. The cards ask for patient response to two questions about their experience, and also ask patients to identify 'Just One Thing' (JOT) the student could do to improve this. JOT cards completed during a two week period were collected to evaluate and analyse the nature of patient responses within this model. Over 90% of JOT cards scored the students as 'Excellent' with the remainder scoring the student as 'Good' or giving no response. Many of the free text comments complimented the students and also provided focused suggestions for improvement. While the overwhelming positive responses may suggest that this model for collecting feedback may not be effective at discriminating between students with varying levels of interpersonal/communication skills, the free text comments were seen to be of value in building confidence or identifying areas for improvement.
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Retroalimentación Formativa , Satisfacción del Paciente , Atención Odontológica/normas , Humanos , Estudiantes de OdontologíaRESUMEN
INTRODUCTION: Providers of education programmes are required to demonstrate to students, staff and external regulators the content of the programme and how this aligns to key outcomes. Whilst many programme themes are straightforward to illustrate, other integral themes prove challenging to demonstrate independently. INNOVATION: A virtual course takes elements within the current programme relating to a specific theme, repackages and maps them to provide clear signposting by highlighting each occasion the theme is taught, experienced and assessed. The individual elements remain within their current course, so there is no disruption to the established curriculum, but there is an enhancement in terms of transparently displaying linkages within a theme. DISCUSSION: Using the concept of virtual courses we have found we can respond to new initiatives and requirements of external regulators, as well as providing improved signposting for staff and students. This can be undertaken without the need to redesign a whole curriculum. CONCLUSION: In well-designed and currently effective curricula, we would like to recommend that virtual course development can enhance programme transparency, demonstrate external regulatory requirements and promote quality assurance without disruption to current content.
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Instrucción por Computador/métodos , Educación en Odontología/métodos , Interfaz Usuario-Computador , Curriculum , HumanosRESUMEN
Measurement of circulating luteinizing hormone (LH) concentrations in cats and temporal changes following ovariohysterectomy (OHE) or possibly GnRH vaccination may be informative for assessing their fertility, contraception or sterilization status. In this study, serum LH concentrations were measured in domestic cats (n = 6) immediately prior to and up to 120 days post-OHE. Basal LH concentrations of females previously subjected to OHE (n = 4; ~1.5 years post-OHE) were compared pre- and post-vaccination with a GnRH immunocontraceptive, and to LH concentrations in intact females. Basal serum LH concentrations (2.67 ± 0.43 ng/ml; mean ± SEM) in intact females increased (p < .01) by 30 days post-OHE (5.65 ± 0.87 ng/ml) but then declined (p < .05) to pre-OHE levels (mean range, 3.26-3.62 ng/ml) at days 60-120 post-OHE. Serum LH (3.84 ± 0.51 ng/ml) in four females ~1.5 years after OHE tended to be higher (p = .10) than those of intact females prior to OHE. Three months following first or second GnRH immunocontraceptive vaccine treatment, serum LH values in females previously subjected to OHE decreased (p < .05) to concentrations similar to those observed in intact females. Our preliminary results suggest that OHE of domestic cats causes a marked increase in basal LH levels within the first few weeks after ovariohysterectomy followed by a return to pre-OHE basal values over the next several months. Reduced LH concentrations after GnRH vaccine may indicate the effectiveness of the immunocontraceptive in reducing the circulating levels of GnRH, thereby reducing secretion of LH.
Asunto(s)
Gatos , Anticoncepción Inmunológica/veterinaria , Hormona Liberadora de Gonadotropina/inmunología , Histerectomía/veterinaria , Hormona Luteinizante/sangre , Ovariectomía/veterinaria , Animales , Anticoncepción Inmunológica/métodos , Femenino , Vacunación/veterinariaRESUMEN
Semen banking of domestic cats and wild felids represents a vital resource for their long-term conservation, but current methods require access to advanced training and specialized equipment. A newer method of semen collection, urethral catheterization of medetomidine-treated cats, allows recovery of high sperm numbers, but it is unclear if this approach permits maximal sperm recovery or is feasible using less expensive alpha-2 agonists. Similarly, a newer sperm preservation approach, vitrification, offers advantages of simplicity and minimal equipment needs, but its efficacy in combination with urethral catheterization has not been investigated. Our specific objectives were to (i) evaluate sequential semen recovery with urethral catheterization and electroejaculation in domestic cats, (ii) assess the effectiveness of a weak (xylazine) versus strong (dexmedetomidine) alpha-2 agonist for inducing sperm release, and (iii) compare post-thaw sperm motility, acrosome status and fertilizing capacity of catheter-recovered samples after vitrification or straw freezing. Results indicated that electroejaculation following repeated catheterization allowed recovery of additional spermatozoa (range, 11-32 × 106 sperm/male) and that xylazine was ineffective for inducing meaningful sperm release (range, 0-0.4 × 106 sperm/male). Post-thaw motility and acrosome status of vitrified catheter samples did not differ (p > .05) from that of straw frozen samples. Preliminary results indicated that in vitro fertilization success (9/30, 30%) of vitrified catheter sperm did not differ (p > .05) from that observed with straw frozen samples (17/30, 57%). In conclusion, urethral catheterization of dexmedetomidine-treated cats allows recovery of substantial sperm numbers but electroejaculation still may be warranted for maximal sperm recovery. Xylazine is not suitable as an inexpensive alternative to dexmedetomidine for catheterization. Vitrification of catheter samples results in comparable post-thaw parameters to straw freezing and may be adequate for use with oviductal insemination procedures.
Asunto(s)
Gatos , Criopreservación/veterinaria , Felidae , Preservación de Semen/veterinaria , Bancos de Esperma/métodos , Cateterismo Urinario/veterinaria , Acrosoma , Agonistas de Receptores Adrenérgicos alfa 2 , Animales , Dexmedetomidina/administración & dosificación , Eyaculación , Estimulación Eléctrica , Fertilización In Vitro/veterinaria , Calor , Masculino , Preservación de Semen/métodos , Manejo de Especímenes/métodos , Manejo de Especímenes/veterinaria , Recuento de Espermatozoides/veterinariaRESUMEN
Extensive measurements of calf body temperature are limited in the literature. In this study, body temperatures were collected by taping a data logger to the skin over the tail vein opposing the rectum of Holstein calves between 4 and 60d of age during 3 different periods of the summer and fall. The summer period was separated into moderate (21-33°C average low to high) and hot (25-37°C) periods, whereas the fall exhibited cool (11-19°C) ambient temperatures. Tail temperatures were compared in a mixed model ANOVA using ambient temperature, age of calf, and time of day (10-min increments) as fixed effects and calf as a random effect. Measures within calf were modeled as repeated effects of type autoregressive 1. Calf temperature increased 0.0325°C (±0.00035) per 1°C increase in ambient temperature. Body temperature varied in a distinct, diurnal pattern with time of day, with body temperatures being lowest around 0800h and highest between 1700 and 2200h. During periods of hot weather, the highest calf temperature was later in the day (~2200h). Calf minimum, maximum, and average body temperatures were all higher in hot than in moderate periods and higher in moderate than in cool periods.
Asunto(s)
Temperatura Corporal , Temperatura , Animales , Bovinos , Calor , Estaciones del AñoRESUMEN
Calves fed >0.7kg of dry matter from milk replacer (MR) typically have greater growth preweaning but lower growth postweaning. This is partially explained by lower digestibility of starter due to less development of the rumen at and after weaning; however, it is unclear when digestibility matures postweaning to levels typical of mature ruminants. Thus, we fed Holstein calves (initially 2 to 3d of age) 3 MR programs (MOD=0.66kg daily for 39d, and then 0.33kg daily for 3d, n=15 calves; HIMOD=0.88kg daily for 5d, then 1.1kg daily for 23d, then 0.66kg daily for 18d, and then 0.33kg daily for 3d, n=16 calves; HI=0.88kg daily for 5d, then 1.1kg daily for 37d, and then 0.56kg daily for 7d, n=15 calves). The MR consisted of 28% crude protein and 20% fat and was reconstituted to 14% solids and fed at 0630 and 1400 h daily. A 39% starch textured starter (19% crude protein) was fed free-choice for the first 56d of a nursery trial with calves in individual pens. From 56 to 112d, calves were grouped by MR program into pens of 3 to 4 calves and offered a starter with the same ingredient composition blended with 5% chopped grass hay for ad libitum consumption. Digestion was estimated at 11 and 16wk. Measurements in the first and second 56d were analyzed separately in a completely randomized design using repeated measurements when applicable. Preplanned contrasts of MOD versus HIMOD and MOD versus HI were used to separate means. Milk replacer dry matter intake was 26.6, 42.4, and 48.7kg in calves fed MOD, HIMOD, and HI, respectively. Starter intake was less for calves fed HIMOD and HI versus MOD from 3 to 8wk. Efficiency of metabolizable energy and protein used for body weight gain did not differ among programs. During the second 56d, body weight gain and hip width changes were greater for calves fed MOD than HI. Total 112-d body weight gain and total hip width changes were 101.4, 101.3, and 101.7kg, and 9.0, 9.1, and 8.7cm for MOD, HIMOD, and HI, respectively. Digestibility of all nutrients except starch were greater at 16 versus 11wk of age. Digestibility of dry matter, organic matter, neutral detergent fiber, and acid detergent fiber were less for HI versus MOD at 11wk of age explaining much of the why postweaning body weight gain advantages were lost postweaning in calves fed the HI program. Feeding more than 0.66kg of dry matter intake from a MR during the preweaning phase did not increase total body weight or hip width gain from 0 to 4mo of age.
Asunto(s)
Alimentación Animal/análisis , Dieta/veterinaria , Digestión , Sustitutos de la Leche/química , Animales , Bovinos , Fibras de la Dieta/administración & dosificación , Femenino , Rumen , Almidón/administración & dosificación , Destete , Aumento de PesoRESUMEN
Calves fed large amounts of milk replacer (MR) gain more body weight preweaning than calves fed less MR; however, postweaning growth may be reduced because of impaired digestion of nutrients. This was explored in the current research, as was the inclusion of functional fatty acids (NT) that could ameliorate some poor growth and digestion issues in calves fed large amounts of MR. Two MR rates [moderate (MOD) or aggressive (AGG)] with and without NT were compared using 48 male Holstein calves initially 3d old (43±1.5kg of body weight) randomly assigned to treatments. The MOD rate was fed at 0.66kg of dry matter (DM) for 49d. The AGG rate was fed for 4d at 0.66kg of DM, 4d at 0.96kg of DM, then 34d at 1.31kg of DM, followed by 0.66kg of DM for the last 7d. Calves were completely weaned at 49d. The MR contained 27% crude protein and 17% fat. The textured starter was 20% crude protein. Starter and water were fed free-choice for the first 56d when calves were housed in individual pens. From 56 to 112d, calves were grouped (4 calves/pen), maintaining the same MR rate and NT treatments, and fed starter blended with 5% chopped grass hay free-choice with free-choice water. Digestibility was estimated from fecal collections made on d 19 to 23, 40 to 44, and 52 to 56. Data were analyzed as a completely randomized design with a factorial arrangement of MR rate and NT using repeated measures with a mixed procedure. Fiber and starch digestion increased with age and was lower for AGG versus MOD. Calf average daily gain and hip width change were greater before approximately 6wk of age for AGG versus MOD, but this was reversed from approximately 6 to 16wk. Calves fed AGG had lower average daily gain per unit intake of DM, crude protein, and metabolizable energy from 8 to 16wk than calves fed MOD. Preweaning starter intake was less for calves fed AGG versus MOD. Calves fed AGG had greater body weight gain than MOD over 112d, but hip width change did not differ. Feeding NT improved digestibility of organic matter, DM, neutral detergent fiber, and acid detergent fiber (over 50% improvement for neutral detergent fiber and acid detergent fiber), which resulted in 10.7kg (13%) more body weight gain and 1.4cm (16%) more hip width change over 112d. This was a greater improvement in growth than the difference in AGG and MOD programs over 112d.
Asunto(s)
Ácidos Grasos , Sustitutos de la Leche/administración & dosificación , Alimentación Animal , Animales , Animales Recién Nacidos/metabolismo , Bovinos , Dieta/veterinaria , Digestión , DesteteRESUMEN
Two 56-d trials with weaned Holstein dairy calves (initially 72 ± 1.8 kg of body weight, 58 to 60 d of age) fed 95% concentrate and 5% chopped grass hay diets were conducted. Each trial used 96 calves (4 calves/pen). During 15 of the last 21 d of the first trial and 10 of 14 d of the second and third week of the second trial, fecal samples were taken to estimate digestibility using acid-insoluble ash as an internal marker. Digestibility estimates along with 56-d average daily gain (ADG), hip width change, body condition score, and fecal score were analyzed with pen as the experimental unit. In trial 1, a textured diet (19% crude protein) with high starch [52% starch, 13% neutral detergent fiber (NDF)] based on whole corn and oats or a pelleted low-starch (20% starch, 35% NDF), high-digestible fiber diet were used. Within starch level, diets were formulated from supplemental soybean meal or soybean meal with blood meal and Alimet (Novus International Inc., St. Charles, MO) to provide 2 metabolizable protein levels (1 and 1.07% metabolizable lysine plus methionine). The 4 treatments were analyzed as a completely randomized design with a 2 by 2 factorial arrangement (6 pens/diet). In trial 2, all pelleted diets (19% crude protein) were fed. Diets were based on soybean hulls, wheat middlings, or corn, which contained increasing concentrations of starch (13, 27, and 42% starch and 42, 23, and 16% NDF, respectively; 8 pens/diet). Contrast statements were constructed to separate differences in the means (soybean hulls plus wheat middlings vs. corn; soybean hulls vs. wheat middlings). In trial 1, intake of organic matter (OM) did not differ. Digestibility of OM was greater in calves fed high- versus low starch-diets. Digestibility of NDF and starch were less in calves fed the high- versus low-starch diets. Calf ADG and hip width change were greater for high- versus low-starch diets. Source of protein did not influence digestibility or ADG. In trial 2, intake of OM was not different. Digestibility of OM was greater in calves fed corn versus other diets. Digestibility of NDF was greater for calves fed soybean hulls versus wheat middlings. Starch digestibility was not different among treatments. Calf ADG and hip width change were greater in calves fed corn versus other diets. High-starch diets were more digestible and supported more growth in 2- to 4-mo-old dairy calves than replacing starch with digestible fiber. Manipulating metabolizable protein compared with a control diet that was predominately corn and soybean meal did not alter growth or digestibility.
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Alimentación Animal/normas , Bovinos/fisiología , Dieta/veterinaria , Carbohidratos de la Dieta/metabolismo , Digestión/fisiología , Lisina/metabolismo , Metionina/metabolismo , Alimentación Animal/análisis , Animales , Fibras de la Dieta/metabolismo , Almidón/metabolismo , Destete , Zea mays/metabolismoRESUMEN
Assessment development is a fundamental element of curriculum management and a requirement for providers of education to consistently demonstrate attainment of educational standards. Development of authentic, valid and reliable assessment is, however, both challenging and resource intensive. In the UK, dental education standards are regulated by the General Dental Council (GDC). The 'safe beginner' is the threshold determined by the GDC for the passing student - but how do we apply this? This article describes an approach the School of Dental Sciences at Newcastle University has adopted to address the challenges associated with developing assessments. Sessional clinical teachers contribute a significant proportion of the clinical supervision within the BDS programme and also have a good appreciation of both the standard and concept of the 'safe beginner'. By implementing a process of active timetable management, we have identified time where this group could contribute to assessment development. We believe that aspects, which could be enhanced by their involvement, include writing, validation, standard-setting and utilisation of assessment. To achieve this, we recognise a requirement for investment in careful manpower planning and training, but consider that it is realistic and beneficial to include sessional clinical teachers in this essential part of learning and teaching.
Asunto(s)
Educación en Odontología/métodos , Evaluación Educacional/métodos , Curriculum , Educación en Odontología/normas , Humanos , Enseñanza , Reino UnidoRESUMEN
Calves fed large amounts of milk replacer (MR) gain more body weight preweaning than calves fed less-aggressive programs; however, postweaning growth may be reduced. Limited research suggests that less than optimal digestion of the postweaned diet due to large amounts of MR with reduced dry feed intake preweaning may contribute to growth impairment postweaning. Current research was conducted to compare growth and postweaning digestion in 3-d-old male Holstein calves fed various MR programs. The MR programs were a conventional [CON; 0.44 kg of dry matter (DM) 21% crude protein (CP), 21% fat powder fed for 42d], moderate (MOD; 0.66 kg of DM 27% CP, 17% fat powder fed for 42d), and aggressive program (AGG; up to 0.87 kg of DM 27% CP, 17% fat powder fed for 49d). All calves were fed a 20% CP textured starter and water ad libitum for 56d. The trial used 96 calves (initially 41 ± 1.9 kg of body weight) received 5 wk apart in 2 groups of 48 calves. During d 51 to 56, fecal samples were collected from 5 calves per treatment randomly selected from calves in the first group. Selected nutrients and acid-insoluble ash (used as an internal flow marker) were analyzed in the starter and feces to estimate digestibility. Data were analyzed as a randomized complete block design with starting time of each group of calves as a block. Repeated measure analysis was performed on overall (0 to 56d) data. Means were separated with a protected least significant difference test. Pen was the experimental unit. Calves fed CON had the least average daily gain [CON=0.35, MOD=0.51, and AGG=0.55 kg/d; standard error of the mean (SEM)=0.018], feed efficiency (CON=0.35, MOD=0.49, and AGG=0.48 gain/feed, SEM=0.016), and change in hip width (CON=3.3, MOD=4.1, and AGG=4.1cm, SEM=0.20) compared with calves fed other programs. Calves fed AGG had the greatest change in BCS and least starter intake compared with calves fed the other programs. Digestibility of organic matter was 79, 78, and 68% and neutral detergent fiber was 54, 51, and 26% for calves fed programs CON, MOD, and AGG, respectively, and were least for calves fed AGG. These results indicate that postweaning digestion is lower than optimal and contributes to lower postweaning growth in calves fed aggressive compared with conventional or moderate MR programs.
Asunto(s)
Alimentación Animal/análisis , Peso Corporal/fisiología , Dieta/veterinaria , Digestión/fisiología , Factores de Edad , Animales , Bovinos , Heces/química , Masculino , Leche , Distribución AleatoriaRESUMEN
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 , DesteteRESUMEN
Energy demands for calves can increase during periods of heat and cold stress. One way to potentially increase energy intake is to increase the energy density of the feed with fat. Trial 1a compared a control starter with no added fat or oil (CON) to starters with 2% tallow (TAL) and 2% soybean oil (SBO). Starters were 20% crude protein (CP) and 45 to 47% starch. Male Holstein calves that were initially 3 to 5d of age were fed a 27% CP, 17% fat milk replacer at 0.66kg of dry matter daily and fully weaned by 42d of a 56-d trial. Trial 1b estimated the digestion of the diets (employed chromic oxide as an indigestible digesta flow marker) using a subset of 5 weaned calves per treatment between d 52 and 56. Trial 2 used Holstein calves initially 59 to 61d of age fed starters CON and SBO blended with 5% chopped grass hay over a 56-d trial. Trial 3 used Holstein calves initially 59 to 61d of age fed starters CON and TAL blended with 5% chopped grass hay over a 56-d trial. Treatments were compared using repeated measures (where appropriate) in a completely randomized design. In trials 1a and 1b, preplanned contrasts compared CON versus TAL and CON versus SBO. Compared with CON, calves fed SBO had reduced starter intake, average daily gain, and digestion of dry matter, organic matter, and CP before 8wk of age. Compared with CON, calves fed SBO had reduced average daily gain and change in hip width from 2 to 4 mo of age. Compared with CON, calves fed TAL had reduced average daily gain and tended to have reduced change in hip width from 2 to 4 mo of age. Calculated metabolizable energy intake was not increased in any trial by added fat or oil. Tallow and soybean oil inclusion at 2% of the starter feed was not advantageous for calf growth before 4 mo of age.
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Bovinos/fisiología , Digestión/efectos de los fármacos , Ingestión de Energía/efectos de los fármacos , Grasas/metabolismo , Aceite de Soja/metabolismo , Alimentación Animal/análisis , Animales , Bovinos/crecimiento & desarrollo , Dieta/veterinaria , Suplementos Dietéticos , Grasas/administración & dosificación , Masculino , Distribución Aleatoria , Aceite de Soja/administración & dosificaciónRESUMEN
The ability to reduce incidence of disease in calves and improve early vaccination strategies is of particular interest for dairy producers. The n-3 fatty acids have been reported to reduce inflammatory diseases in humans but limited research has been done in calves. The objective of this study was to compare supplementation of n-3 fatty acids from fish and flax oil on gene expression of whole blood cells and growth of milk-fed Holstein calves. Forty-eight Holstein bull calves from a commercial dairy were randomly assigned to 1 of 3 diets beginning at 4d old: (1) control milk replacer (MR) with all pork fat, (2) MR with 2% flax oil, and (3) MR with 2% fish oil. All MR were 17% fat, 27% crude protein on a dry matter (DM) basis, with all protein from whey sources. Calves were each fed 654g DM of MR daily for the first 25d and then 327g/d for d26, 27, and 28. On d28, calves were challenged with a Pasteurella vaccine and the temperature response to the vaccine was recorded. Milk and feed intake and fecal scores were recorded daily, and body weight and hip width were recorded weekly. Blood was collected from all calves on d25. One tube of collected blood was incubated with endotoxin (lipopolysaccharide; LPS) for 2h and frozen with a second tube of control blood. Quantitative real-time PCR was used to assess the effects of LPS stimulation on cytokine gene expression. During the 28 d, calves supplemented with flax oil had a greater growth rate and feed efficiency than calves fed fish oil (0.52±0.02 vs. 0.48±0.02g of gain:g of feed). Fish oil tended to decrease LPS stimulation of tumor necrosis factor-α expression. Flax oil, but not fish oil, decreased the expression of IL-4 and tended to decrease expression of osteopontin and IL-8. Flax oil tended to reduce the increase in rectal temperature in response to a Pasteurella vaccine. In conclusion, our data support the idea that supplementation with n-3 fatty acids affects cytokine gene expression.
Asunto(s)
Alimentación Animal , Suplementos Dietéticos , Ácidos Grasos Omega-3/administración & dosificación , Aceites de Pescado/administración & dosificación , Aceite de Linaza/administración & dosificación , Animales , Peso Corporal , Bovinos , Dieta/veterinaria , Interleucina-4/genética , Interleucina-4/metabolismo , Interleucina-8/genética , Interleucina-8/metabolismo , Lipopolisacáridos/efectos adversos , Reacción en Cadena en Tiempo Real de la Polimerasa , Porcinos , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Typical fatty acid profiles of milk and milk replacer (MR) differ. Calf MR in the United States are made from animal fat, which are low in short- and medium-chain fatty acids and linolenic acid. Two 56-d trials compared a control MR containing 27% crude protein and formulated with 3 fat and fatty acid compositions. The 3 MR treatments were (1) only animal fat totaling 17% fat (CON), (2) animal fat supplemented with butyrate, medium-chain fatty acids, and linolenic acid using a commercial product (1.25% NeoTec4 MR; Provimi North America, Brookville, OH) totaling 17% fat (fatty acid-supplemented; FA-S), and (3) milk fat totaling 33% fat (MF). The MR were fed at 660 g of dry matter from d 0 to 42 and weaned. Starter (20% crude protein) and water were fed ad libitum for 56 d. Trial 1 utilized Holstein calves (24 female, 24 male) during summer months and trial 2 utilized Holstein calves (48 male) during fall months. Calves (41±1 kg of initial body weight; 2 to 3d of age) were sourced from a single farm and housed in a naturally ventilated nursery without added heat. Calves were in individual pens with straw bedding. Calf was the experimental unit. Data for each trial were analyzed as a completely randomized design with a 3 (MR treatment) × 2 (sex) factorial arrangement of treatments in trial 1 with repeated measures and as a completely randomized design with 3 MR treatments in trial 2 with repeated measures. Preplanned contrast statements of treatments CON versus FA-S and CON versus MF were used to separate means. We found no interactions of MR treatment by sex. Calf average daily gain, hip width change, and feed efficiency differed (CON
Asunto(s)
Bovinos/crecimiento & desarrollo , Ácidos Grasos/farmacología , Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales/efectos de los fármacos , Animales , Animales Recién Nacidos/crecimiento & desarrollo , Animales Recién Nacidos/inmunología , Butiratos/farmacología , Bovinos/inmunología , Virus de la Diarrea Viral Bovina Tipo 1/inmunología , Dieta/veterinaria , Suplementos Dietéticos , Femenino , Inmunidad Humoral/efectos de los fármacos , Inmunidad Humoral/fisiología , Masculino , Vacunas contra la Parainfluenza/inmunología , Vacunas contra la Parainfluenza/farmacología , Virus de la Parainfluenza 3 Bovina/inmunología , Vacunas Virales/inmunología , Vacunas Virales/farmacología , Ácido alfa-Linolénico/farmacologíaRESUMEN
Due to renewed interest in feeding acidified milk replacer (MR) for ad libitum consumption within North America, two 112-d trials were conducted using Holstein calves obtained from one dairy farm at 2 to 3 d of age. In trial 1, a 27% crude protein (whey protein), 17% fat MR powder was reconstituted with water to 14% solids and fed at 0.66 kg of dry matter (DM) per day for 42 d (CON) or acidified to pH 4.2 using citric acid and offered 24h/d for d 0 to 35, then switched to 0.66 kg of DM without acid per d for 7 d (A4). In trial 2, the same MR was fed as CON, ad libitum pH 5.2 MR offered from 0600 to 0800 h and 1600 to 1800 h for d 0 to 21 (R5), ad libitum pH 5.2 MR offered 24h/d for d 0 to 35 (A5), and ad libitum pH 4.2 MR offered 24h/d for d 0 to 35 (A4). After the ad libitum period, calves on R5, A5, and A4 were switched to CON until d 42. Growth measures were made until d 112 in each trial. Data from each trial were analyzed as a completely randomized design with repeated measurements over time using an autoregressive type 1 covariance structure when appropriate. In each trial, calves fed CON had lower average daily gain (ADG) from 0 to 42 d and greater ADG from 42 to 56 d than calves fed the other treatments. In both trials, ADG from 0 to 56 d and 56 to 112 d were not greater for A4 or A5 versus CON. From 56 to 112 d in trial 2, ADG was greater for R 0025 versus A5. Some calves completely rejected the MR at pH 4.2. Calves consumed more of the MR at pH 5.2 than 4.2. Calves fed A4 in trial 1 and treatments A5 and A4 in trial 2 consumed >95% of their MR between 0600 to 0800 h and 1600 to 1800 h. Time spent standing did not differ by treatment in trial 1 and increased from 312 to 332 min/d from d 6 to 56. Under the conditions of these trials, results to 112 d showed no advantage to feeding calves MR acidified to pH 4.2 or 5.2 ad libitum from 0 to 35 d with gradually weaning by 42 d compared with calves fed the control MR fed at 0.66 kg of DM/d. Additionally, when calves were fed MR ad libitum, they consumed >95% of the MR between 0600 to 0800 h and 1600 to 1800 h and standing behavior was not greatly affected.
Asunto(s)
Alimentación Animal , Conducta Alimentaria , Alimentación Animal/análisis , Animales , Animales Recién Nacidos/fisiología , Animales Recién Nacidos/psicología , Bovinos , Ácido Cítrico/análisis , Industria Lechera/métodos , Conducta Alimentaria/fisiología , Conducta Alimentaria/psicología , Masculino , DesteteRESUMEN
Holstein calves, 2 to 5 d of age initially (42.8 ± 2.1 kg of body weight) from a single dairy farm, were transported 3.5h to southwest Ohio. Calves were housed in 1.2 × 2.4m individual pens with wire mesh sides within a curtain sidewall barn with no added heat. Pens were bedded with long straw and fed 0.68 kg (as-fed) of milk replacer powder reconstituted to a 14% dry matter daily in 2 equal meals at 0615 and 1600 h. Starter and water were offered ad libitum. Calves were weaned at 42 d with measurements made until d 56. Ten calves per period in 4 periods of the year (spring/summer, SS; summer, S; fall, F; winter, W) were used to measure standing and lying behavior using an electronic data logger attached to the medial side of the right rear leg of calves. In period SS, loggers were attached from d 2 to 6, 10 to 17, 25 to 32, and 33 to 56. In periods S, F, and W, the logger was attached from d 4 to 56. Standing time was estimated from 5-min interval recordings. Data from the first 2 d after attachment were not used. Standing time did not differ among periods and averaged 303 ± 52.8 min/d. These measurements were low, and approximately 2h/d less than other measurements found in the literature. Standing time differed among sections of the day and was greatest during a.m. and p.m. feeding, intermediate during midday and evening, and least at night. No interaction of period of year by time of day was noted. Standing time increased by 0.52 ± 0.063 min/d with increasing age of calf (approximately 26 min per 7 wk). Variances of standing time within period of year due to calf and variances across periods were compared and did not differ. In summary, calves averaged approximately 300 min/d standing, and time standing increased by approximately 0.5 min/d with age and did not differ with period of year.
Asunto(s)
Bovinos/psicología , Vivienda para Animales , Animales , Animales Recién Nacidos/fisiología , Animales Recién Nacidos/psicología , Bovinos/fisiología , Femenino , Postura , Estaciones del Año , Factores de TiempoRESUMEN
The objective was to compare a proprietary egg yolk-based cryopreservation medium with a chemically defined soy-based medium, as well as to examine effects of temperature of glycerol addition on sperm parameters and IVF after freezing and thawing of domestic cat sperm. Semen was collected from adult cats (four males and three ejaculates per male), divided in four equal aliquots, and extended in either egg yolk with 4% glycerol added before (EYG) or after (EY) cooling to 5 °C, or soy-lecithin with 4% glycerol added before (SLG) or after (SL) cooling to 5 °C. Extended sperm were frozen in straws over liquid nitrogen vapor. Sperm progressive motility (%) and rate of progressive movement (scale of 0-5) were evaluated at 0, 1, 3, 6, and 24 h post-thaw. Sperm capacitation, acrosome integrity, and DNA integrity were assessed at 15 min post-thaw. Effects of media (EY or SL) on IVF success was also examined (three males and three ejaculates per male). Sperm motility was greater (P < 0.05) in soy-based compared with egg yolk-based media at 3, 6, and 24 h post-thaw. A higher (P < 0.05) percentage of noncapacitated sperm (pattern F) were present in soy-based (SLG, 63.7 ± 9.2%; and SL, 64.1 ± 9.2%) compared with egg yolk-based (EYG, 49.9 ± 7.9%; and EY, 52.4 ± 18.6%) cryopreservation media, regardless of temperature of glycerol addition. Addition of glycerol at 5 °C increased (P < 0.05) percentage of sperm motility at 6 h (EYG 16.3 ± 8.3% vs. EY, 24.0 ± 11.7%; SLG, 36.7 ± 6.5% vs. SL, 42.9 ± 10.1%) and 24 h (EYG, 2.1 ± 3.3% vs. EY, 8.3 ± 3.9%; SLG, 11.3 ± 8.3% vs. SL, 18.8 ± 7.4%) post-thaw in both media. There were no differences (P > 0.05) between cryodiluents in embryo cleavage, percentage of embryos reaching blastocyst, or cell number per blastocyst. The chemically defined, soy-based medium resulted in better preservation of long-term motility and capacitation status of frozen-thawed domestic cat sperm compared with a commercial egg yolk-based extender, without compromising fertilizing ability.