RESUMEN
Considering the relevance of meat discoloration for meat production chain and the conflicting results regarding the influence of feeding regimes on color of fresh beef and the lack of meta-analytic studies on this subject we investigated the effect of grain-fed and pasture-fed regimes on color of beef longissimus from Bos cattle through a systematic review with meta-analysis. A systematic search from 2001 to 2021 was performed in two databases and 126 papers were eligible for meta-analysis. Pasture-fed longissimus beef exhibited higher a* (8.21%) and C* (8.61%) values, and lower h* values (17.18%) than grain-fed counterparts, indicating a greater color for longissimus beef from pasture-fed animals. Among the pasture-fed regimes, those containing alfalfa, bermudagrass, cowpea and pearl millet were the most effective for color improvements. Our findings indicate potential feeding regimes to mitigate global economic losses from meat discoloration and suggest the necessity to develop suitable processing strategies to improve the color of beef from grain-fed Bos cattle.
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Alimentación Animal , Carne , Músculo Esquelético , Alimentación Animal/estadística & datos numéricos , Animales , Bovinos , Color , Grano Comestible , Carne/análisisRESUMEN
Changing consumer shopping behaviors, and specifically the shift towards online procurement of goods and services, have altered the retail landscape of nearly all goods, including pet products and services. Whilst it is known and commonly discussed that less retail business for products and medications is being conducted in clinics than in the past, it is not well documented where that commerce is now taking place, and by what customer segments. For cats, dogs, and other pets, specialty food and food in general was purchased by a high percentage of respondents at the physical store. Sixteen-percent of dog owners, 17 % of cat owners and 14 % of other animal owners purchased prescription food at the veterinarian. Ten percent of dog owners, 10 % of cat owners, and 9 % of other animal owners purchased prescription food from the physical store. A high percentage of cat and dog owners purchased flea and tick preventative, heartworm preventative and prescription medications at the veterinarian, followed by the physical store. Using a choice experiment, both dog and cat owners were willing-to-pay a statistically significant positive amount for having their veterinarian, or a veterinarian in their community (who was not their veterinarian) on the veterinary telemedicine call or video when compared to a veterinarian from outside the community. In relation to the willingness to pay (WTP) for a telemedicine veterinary consultation with a veterinarian outside of the pet owners' community, dog owners were willing to pay $38.04 more for a telemedicine veterinary consultation with their regular veterinarian, and $13.38 more for a telemedicine veterinary consultation with a veterinarian in the dog owners' community. Cat owners had a WTP of $38.12 per call or visit for having their veterinarian as the consultant which was statistically higher than their WTP for a veterinarian in their community, $12.74 when compared to a veterinarian outside their community. When comparing the mean price adjusted WTP between cat and dog owners, there were not any statistically significant differences found. Quantifying pet owner willingness to pay for commonly discussed attributes of telemedicine, such as whether a local veterinarian is consulted (versus a veterinarian from outside the community), facilitates veterinary practice management decision making as practices adjust product and service offerings to meet the changing consumer demand of pet owners in today's marketplace.
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Alimentación Animal/economía , Telemedicina/economía , Medicina Veterinaria/economía , Alimentación Animal/estadística & datos numéricos , Animales , Gatos , Perros , Sistemas en Línea , Mascotas , Medicina Veterinaria/clasificaciónRESUMEN
Animals keep a safe distance to humans and thus humans rarely physically encounter wild animals. However, birds have been known to feed from the hand of humans. Such behaviour must reflect the trade-off between acquisition of food and the risk of being captured by a potential predator feeding from the hand. Relying on YouTube, an international video-sharing platform, we found 36 European bird species recorded feeding from the hand of humans. We compared ecological traits between these species and all other 490 European bird species, which were not recorded as feeding from a human hand. We found that species with a large number of innovative behaviours, a higher rate of introduction success, larger breeding range, larger population size, and urban tolerance have a higher probability of feeding from the hand of a human. These associations were also supported after control for the similarity among taxa due to common phylogenetic descent. In conclusion, these findings suggest that frequent feeding from the hand of a human results in the transition from natural environments to novel urbanized environments with consequences for population size increasing and range expansion.
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Alimentación Animal/estadística & datos numéricos , Aves/fisiología , Ecosistema , Conducta Alimentaria/fisiología , Métodos de Alimentación/veterinaria , Abastecimiento de Alimentos/métodos , Mano/fisiología , Animales , Humanos , Población UrbanaRESUMEN
BACKGROUND: Obesity is a growing problem in UK equine population. Achieving weight loss in obese horses and ponies at risk of laminitis is an important but often challenging objective. METHODS: We hypothesised that supplementing poor winter pasture with a mix of barley straw and hay (50:50) rather than hay alone (group B) would lead to weight loss in grazing equids over winter. For this purpose, a group of 40 horses were fed either the straw mix (group A) or hay alone (group B) over winter. RESULTS: Over the study period, all animals in group A (n=25) lost weight with a mean weight change of -27±17 kg, while in group B (n=15) only 3 out of 15 lost weight (20 per cent), and overall, group B gained weight (+6±18 kg). CONCLUSIONS: This study suggests that straw is a cost-effective and low-energy roughage, which may be a useful alternative to hay alone when trying to induce weight loss in grazing equids over winter. There were no episodes of colic or laminitis during the study period in either group.
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Alimentación Animal/estadística & datos numéricos , Enfermedades de los Caballos/dietoterapia , Obesidad/veterinaria , Pérdida de Peso , Alimentación Animal/economía , Animales , Análisis Costo-Beneficio , Ingestión de Energía , Femenino , Caballos , Masculino , Obesidad/dietoterapia , Estaciones del Año , Resultado del Tratamiento , Reino UnidoRESUMEN
The objective of this study was to evaluate the effects of the inclusion of different levels of licuri cake on the consumption of dry matter and nutrients and ingestive behavior of feedlot crossbred steers. Forty-four crossbred steers with an average age of 24 months and a mean live weight of 358.19 ± 41.57 kg were used in the study. The animals were aleatorically distributed in a completely randomized design made up of four treatments, with 11 animals used per treatment: the control treatment (without the inclusion of licuri cake in the diet) and treatment with the inclusion levels of 8.5, 17, and 25.5% of licuri cake, respectively, in the total dry matter of the diet. The inclusion of licuri cake influenced the intake of dry matter, crude protein, ether extract, neutral detergent fiber corrected for ash and protein, and non-fibrous carbohydrates corrected for ash and protein, each of them showing quadratic behavior. There was an effect of the tested diets on the time spent on food intake and number of idle periods, which presented a quadratic effect, with maximum and minimum values obtained for the inclusion levels of the licuri cake of 16.92% and 11.00%, respectively. There was no effect of the tested diets on the time spent on rumination and idleness. The feed efficiency of the dry matter, the duration of the feeding period, and the duration of the idleness period were influenced by the inclusion of the licuri tart in the diet, presenting a linear decreasing effect. There was an increasing linear effect for the number of feeding periods and the duration of rumination periods. Given the results obtained, it can be concluded that the licuri cake changes the consumption and behavioral parameters of feedlot steers, being recommended its use in up to 8.5% of inclusion in the total dry matter of the diet.
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Alimentación Animal/estadística & datos numéricos , Arecaceae , Bovinos , Dieta/veterinaria , Conducta Alimentaria , Alimentación Animal/análisis , Animales , Fibras de la Dieta , Ingestión de Energía , Masculino , NutrientesRESUMEN
The current study compared the growth performance, carcass and meat quality effects of feeding 150â¯g/kg DM of dried citrus pulp (DCP) or grape pomace (DGP) as alternative dietary fibre sources to 7â¯months-old Angus steers for 90d. Twenty-four steers were assigned to three dietary treatments (8 steers/treatment) in completely randomised design. Each steer was treated as an experimental unit. Feeding the DGP and DCP diets resulted in greater (Pâ¯≤â¯0.05) average daily gain and live weight compared to the control diet. Steers fed the DGP diet had higher (Pâ¯≤â¯0.05) dry matter intake, warm and cold carcass weights than those fed the DCP and control diets. Shear force and income over feed costs were greatest for the DGP diet followed by the DCP and control diets (Pâ¯≤â¯0.05). Current findings suggest DGP is a better fibre source than DCP resulting in enhanced growth performance, carcass attributes and economic viability of feedlot steers.
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Alimentación Animal/estadística & datos numéricos , Fibras de la Dieta/administración & dosificación , Calidad de los Alimentos , Frutas , Extractos Vegetales/administración & dosificación , Carne Roja/análisis , Animales , Bovinos , Dieta/métodos , Masculino , Carne Roja/estadística & datos numéricosRESUMEN
This study was conducted to evaluate the fatty acid profile, sensory properties and lipid oxidation of meat on retail display (RD) from Nellore steers (nâ¯=â¯96) fed diets containing soybean (SOY), sunflower (SUN), or linseed (LIN) oil or a control diet (CON). After slaughtering, samples of the Longissimus muscle were collected for sensory properties (1â¯day), fatty acid composition (1â¯day) and oxidation stability (3â¯days under RDC) evaluations. No differences in total lipids, cholesterol, TBARS, and total SFAs, MUFAs, PUFAs, and PUFA/SFA were observed. However, meat from animals fed vegetable oil had more CLA than that of the CON samples. The flavour, juiciness and overall acceptability were affected by the treatments (Pâ¯<â¯0.05), but no consistent effect of a specific oil source was observed. Meat colour was not affected by diets or days under RD, and 7-ketocholesterol was not detected in any sample. The oil sources used in this work were not effective in consistently changing meat properties.
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Alimentación Animal/análisis , Ácidos Grasos Omega-3/administración & dosificación , Ácidos Grasos Omega-6/administración & dosificación , Calidad de los Alimentos , Metabolismo de los Lípidos/fisiología , Carne Roja/análisis , Alimentación Animal/estadística & datos numéricos , Animales , Bovinos , Humanos , Aceite de Linaza/administración & dosificación , Masculino , Oxidación-ReducciónRESUMEN
The objectives of this study were to compare different models for analysing body weight (BW) and average daily feed intake (ADFI) data collected during a 70-day feedlot test period and to explore whether genetic parameters change over time to evaluate the implications of selection response. (Co)variance components were estimated using repeatability and random regression models in 2,071 Angus steers. Models included fixed effects of contemporary group, defined as herd-year-observation_date-age, with additive genetic and permanent environmental components as random effects. Models were assessed based on the log likelihood, Akaike's information criterion and the Bayesian information criterion. For both traits, random regression models (RRMs) presented a better fit, indicating that genetic parameters change over the test period. Using a two-trait RRM, the heritability from day 1 up to day 70 for BW increased from 0.40 to 0.50, while for ADFI, it decreased from 0.44 to 0.33. The genetic correlation increased from 0.53 at day 1 up to 0.79 at day 70. Selection based on an index assuming no change in genetic parameters would yield a 2.78%-3.13% lower selection response compared to an index using parameters estimated with RRMs and assuming these genetic parameters are correct. Results imply that it may be beneficial to implement RRMs to account for the change of parameters across the feedlot period in feed efficiency traits.
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Alimentación Animal/estadística & datos numéricos , Peso Corporal/genética , Cruzamiento/estadística & datos numéricos , Ingestión de Alimentos/genética , Animales , Teorema de Bayes , Bovinos , Femenino , Masculino , Modelos GenéticosRESUMEN
Growth performances, carcass characteristics and meat quality parameters from growing rabbit fed with two levels of dietary brown seaweed (Laminaria spp) and plant polyphenols were investigated. One hundred and forty-four New Zealand White rabbits were allotted into three dietary treatments containing 0 (C), 0.3% (T1), and 0.6% (T2) of brown seaweed and plant polyphenols mixture for 42â¯days. Growth performances and carcass weight were improved in T1 group. Vitamin A and E content in Longissimus thoracis and lumborum (LTL) and Semimembranosus (SM) muscle were enhanced in the treated groups. In the SM muscle, the oxidative stability was improved in rabbit fed with both dosages of dietary supplement, and the cholesterol content tended to be lower in T1 than in T2 and C groups. The LTL and SM muscle sensory characteristics were improved. In conclusion, dietary integration with a low dosage of brown seaweed and plant polyphenols is a valid strategy for enhance growth performance and produce healthier rabbit meat.
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Alimentación Animal/estadística & datos numéricos , Dieta/métodos , Calidad de los Alimentos , Carne/análisis , Polifenoles/administración & dosificación , Algas Marinas , Animales , Conejos/crecimiento & desarrolloRESUMEN
Contamination of feed by mycotoxins is a global epidemic that has a sizeable impact on animal health and causes economic losses. Mycotoxins, including aflatoxins (AFs), zearalenone (ZEN), fumonisins (FUMs), deoxynivalenol (DON), and ochratoxin A (OTA), lead to acute and chronic adverse effects in pigs. Animal feed and feed ingredients are commonly contaminated by one or more mycotoxins worldwide; however, the prevalence of mycotoxin contamination in feed and feed ingredients in Taiwan remains unclear. A total of 820 cornmeal and corn-based swine feed (pregnancy and nursery diets) samples provided by feed and animal producers were analyzed using the enzyme-linked immunosorbent assay method between January 2015 and December 2017 to determine the presence of mycotoxins. The results revealed that the most prevalent mycotoxin in Taiwan was DON, with 91.4% of positive samples between 2015 and 2017, followed by ZEN, AFs, and FUMs, with 70.2%, 58.0%, and 50.4% of positive samples, respectively. A similar prevalence of mycotoxins was observed in cornmeal and corn-based swine feed. Furthermore, 7.7% of the analyzed feed samples contained one mycotoxin, and 91.3% contained multiple mycotoxins. DON was the most prevalent mycotoxin in cornmeal and corn-based swine feed in Taiwan. Moreover, a high incidence of contamination by multiple mycotoxins was observed in swine feed. Awareness of mycotoxin presence in feed and development of mycotoxin detoxification strategies are unmet needs.
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Alimentación Animal/análisis , Contaminación de Alimentos/análisis , Micotoxinas/análisis , Aflatoxinas , Alimentación Animal/estadística & datos numéricos , Animales , Dieta , Ensayo de Inmunoadsorción Enzimática , Contaminación de Alimentos/estadística & datos numéricos , Fumonisinas , Ocratoxinas , Porcinos , Taiwán , Tricotecenos , Zea mays , ZearalenonaRESUMEN
In Nigeria, helminths have over the last decades been established as important parasite of poultry including pigeons. However, the prevalence of these parasites of pigeons in Kano State is yet to be established. The prevalence of helminth parasites of domestic pigeon (Columba livia domestica) in Kano State, Nigeria was investigated in this study. The differences in the prevalence of infection between the pigeons examined on the basis of sex of the pigeon and season of the year were analyzed statistically using the students' "t" -test. The intestinal contents of 144 pigeons were examined for gastrointestinal helminths between February and April representing the dry season and between June and August for the wet season. Pigeons were grouped according to Squabs (chicks) (0-4â¯weeks), Squeakers (Juveniles) (5-8â¯weeks) and Youngsters (Adults) (9â¯weeks onwards). Intestinal parasites found include Cestodes: Raillietina tetragona, 20 (13.80%), R. echinobothrida, 11 (7.64%), Amoebotaenia cuneata, 5 (3.47%), Hymenolopis contaniana, 10 (6.95%), Davainea proglottina, 1(0.69%) and Ornithostrongylus quadriatus 1(0.69%). Nematodes: Capillaria obsignata, 10(6.95%) and Ascaridia columbae, 9(6.25%). Forty-two (29.16%) of the birds had mild infection, 17 (11.81%) had moderate infection, 9 (6.25%) and 2(1.39%) had heavy and severe infection, respectively. The prevalence was higher during the wet season (36.65%) than during the dry season (27.97%). Of all the age groups, only Youngsters, 34 (23.61%) were infected with intestinal helminths. However, there were statistically significant differences between the age, sex and seasons in this study (Pâ¯<â¯0.005). Pigeons raised on semi-intensive had the highest rate of infection (37.50%) and those raised on intensive management had the lowest rate of infection (9.03%). A number of measures are recommended for the control of these helminthic parasites.
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Enfermedades de las Aves/epidemiología , Columbidae/parasitología , Helmintiasis Animal/epidemiología , Parasitosis Intestinales/veterinaria , Distribución por Edad , Alimentación Animal/clasificación , Alimentación Animal/estadística & datos numéricos , Crianza de Animales Domésticos/métodos , Animales , Enfermedades de las Aves/parasitología , Infecciones por Cestodos/epidemiología , Infecciones por Cestodos/veterinaria , Métodos de Alimentación/veterinaria , Femenino , Vivienda para Animales/normas , Parasitosis Intestinales/epidemiología , Masculino , Infecciones por Nematodos/epidemiología , Infecciones por Nematodos/veterinaria , Nigeria/epidemiología , Oportunidad Relativa , Prevalencia , Estaciones del Año , Distribución por SexoRESUMEN
We address the hypothesis that individual cow feed intake can be measured in commercial farms through the use of a photogrammetry method. Feed intake and feed efficiency have a significant economic value for the farmer. A common method for measuring feed mass in research is a feed mass weighing system, which is excessively expensive for commercial farms. However, feed mass can be estimated by its volume, which can be measured by photogrammetry. Photogrammetry applies cameras along the feed-lane, photographing the feed before and after the cow visits the feed-lane, and calculating the feed volume. In this study, the precision of estimating feed mass by its volume was tested by comparing measured mass and calculated volume of feed heaps. The following principal factors had an impact on the precision of this method: camera quality, lighting conditions, image resolution, number of images, and feed density. Under laboratory conditions, the feed mass estimation error was 0·483 kg for heaps up to 7 kg, while in the cowshed the estimation error was 1·32 kg for up to 40 kg. A complementary experiment showed that the natural feed compressibility causes about 85% of uncertainty in the mass estimation error.
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Alimentación Animal , Bovinos/fisiología , Industria Lechera/métodos , Fotogrametría/veterinaria , Alimentación Animal/análisis , Alimentación Animal/economía , Alimentación Animal/estadística & datos numéricos , Animales , Ingestión de Alimentos , Femenino , Monitoreo Fisiológico/métodos , Fotogrametría/instrumentación , Sensibilidad y EspecificidadRESUMEN
PURPOSE: Early postnatal nutrition not only holds relevance to infant growth, but also determines the risk of developing obesity and chronic diseases such as diabetes type 2 and cardiovascular diseases in adulthood. It is suggested that a high-protein (HP) diet in early childhood can predispose children to obesity. However, data concerning possible alterations in milk composition and the development of the offspring in response to a maternal HP diet are currently not available. To address this question, we conducted a study using pigs as a model organism. METHODS: At parturition, sows were assigned to two experimental groups. During lactation, the control group received a diet with a protein content of 16%, whereas the diet of the HP group contained 30% protein. After 28 days of lactation, samples were taken from sows and piglets for the quantification of free amino acids and other metabolites and for histology. RESULTS: Serum and milk urea showed the most marked differences between the two groups of sows, whereas serum urea concentration in piglets did not differ. Here, we found that the intake of an HP diet changed a series of metabolites in sows, but had only small effects on milk composition and virtually no effects on growth in the offspring. Interestingly, maternal protein intake during lactation shapes the microbiome of the offspring. CONCLUSION: From our current study, we conclude that even a very high maternal protein intake throughout lactation has no impact on growth and health parameters of the offspring.
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Alimentación Animal/estadística & datos numéricos , Fenómenos Fisiológicos Nutricionales de los Animales/fisiología , Dieta Rica en Proteínas , Lactancia/fisiología , Leche/química , Animales , Animales Lactantes/fisiología , Femenino , Modelos Animales , PorcinosRESUMEN
As commercial free-range and pastured poultry production has gained increased popularity in the United States in recent years, there is a greater need to understand basic husbandry practices including feeding and lighting practices. Because husbandry practices vary greatly between individual commercial pastured poultry and free-range operations, gaining knowledge across a wide cross-section of producers is necessary to better understand current practices. Specifically, because feed is considered the most expensive part of poultry production with respect to operating cost, in collaboration with the American Pastured Poultry Producers Association, an on-line survey of commercial free-range and pastured poultry producers was conducted aimed primarily at evaluating feeding and lighting practices. Data were collected from 14 commercial pastured (n = 13) and free-range (n = 1) producers (6 broiler, 1 layer, and 7 broiler/layer facilities) across 9 U.S. states. Results showed that these operations most commonly use Cornish Cross for broiler production and ISA Brown and Australorp for egg production. Only 1 of the 14 farms calculates feed conversion ratio on a monthly basis. Estimates of Hen Month Egg Production (HMEP) resulted in HMEP percentages that were over 100% in 6 of the 7 farms that provided data. 5 of the 7 farms that have layers used supplemental lighting but do not use a lux meter. These lack of data reflect an important challenge with this segment of the poultry industry. Extension based outreach focused on enabling data collection and record-keeping and analysis are necessary. Despite its small sample size, this study's results provide some valuable insights with respect to feeding equipment and the current state of data collection for this segment of the poultry industry.
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Alimentación Animal/estadística & datos numéricos , Crianza de Animales Domésticos/métodos , Pollos/fisiología , Iluminación/estadística & datos numéricos , Animales , Pollos/clasificación , Femenino , Masculino , Encuestas y Cuestionarios , Estados UnidosRESUMEN
Determining the efficiency of amino acid (AA) utilization in growing animals is crucial to estimate their requirement accurately. In broiler chickens, the composition of AA in feather is different from feather-free body and the proportion of feathers will change along broiler's growth, which may impact the efficiency of utilization on AA consumed. Therefore, in order to establish a method that predicts the efficiency of utilization for feather-free body and feather, two approaches were evaluated: a multiple linear regression and a multivariate analysis. Additionally, a new factorial model was proposed to predict AA requirements in broiler chickens. Data from 13 trials that evaluated the requirements for lysine (Lys), sulphur AA (SAA), threonine (Thr), and valine (Val) in male broilers were used for the analyses. Both methods of analysis were consistent in showing that the efficiency of utilization in feather-free body and feather were different. Using multiple linear regression, the values of efficiency of utilization estimated in feather-free body were 0.68, 0.72, 0.81, 0.79 (mg of amino acid deposited / mg of amino acid consumed above maintenance) and in feather were 0.58, 0.77, 0.78, and 1.57 (mg/mg) for Lys, SAA, Thr, and Val, respectively. Applying the multivariate approach, the corresponding predicted values were 0.68, 0.67, 4.23, 0.27 (mg/mg) in feather-free body and 1.16, 0.86, 0.16, and 1.10 (mg/mg) in feather, respectively. According to the results, efficiency of utilization may be related, to some extent, on the concentration determined in each tissue. The uncertainty around the amount of AA consumed for gain directed to feather-free body or feather deposition could be a limitation for multivariate analyses. The results indicated that multiple linear regression predictions may be better estimates of utilization efficiency. However, more studies are needed to elucidate the effect of age on deposition and partitioning of dietary AA in different parts of the broiler.
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Aminoácidos/metabolismo , Fenómenos Fisiológicos Nutricionales de los Animales , Composición Corporal , Pollos/crecimiento & desarrollo , Dieta , Proteínas en la Dieta/farmacocinética , Aminoácidos Sulfúricos/metabolismo , Alimentación Animal/análisis , Alimentación Animal/estadística & datos numéricos , Animales , Composición Corporal/efectos de los fármacos , Composición Corporal/fisiología , Pollos/metabolismo , Dieta/estadística & datos numéricos , Metabolismo Energético/fisiología , Modelos Lineales , Lisina/metabolismo , Masculino , Análisis Multivariante , Treonina/metabolismo , Valina/metabolismo , Aumento de Peso/fisiologíaRESUMEN
1. Enzymes have been used commercially for nearly 40 years and save significant costs through sparing of expensive nutrients but the mechanism by which this is achieved is still debated. 2. The research focused on non-starch polysaccharidase (NSPase) enzymes is used as an example of where greater progress could have been made if the details of the work had been described more fully and the analysis of the data generated had been broader in scope and more critical. 3. Lack of standardisation of the details presented in the materials and methods has been identified as a significant barrier to meaningful retrospective analysis and thus limits advances in the understanding of the mode of action of these enzymes. 4. The identity of the enzyme employed and its activity is often lacking, and more importantly the purity is rarely disclosed. Contaminant activities which are neither listed nor assayed could play a significant role in the responses observed. 5. The dose optimum of most enzymes is often considerably higher than that employed in most studies. Thus studies claiming synergy between two 'activities' should ensure that the response is not related to each enzyme simply augmenting the dose of just one activity in the finished feed. This is a common problem, and coupled with the lack of factorial experiments to justify the presence of each enzyme in a multi-enzyme product, it is not surprising that there is still debate as to whether single or multi-enzymes are best suited poultry rations. 6. The three proposed mechanisms for NSPases (viscosity, cell wall and prebiotic) are discussed, and along with their strengths and weaknesses it is suggested that a re-evaluation of each is needed. Viscosity may have to be re-evaluated as being a function not only of the cereal being fed, but of the age of the animal as well. The cell wall theory as described is poorly modelled in vitro and hence the validity of these data is questioned. The prebiotic theory may need significant modification as it appears that the quantities of oligomers produced are insufficient to generate the additional volatile fatty acids (VFA)'s reported. It is likely that all three mechanisms play a role in the responses observed, but the prebiotic mechanism probably plays by far the most important part in low viscosity diets. 7. Future research would be improved if it considered all potential mechanisms when designing a trial. Significant failings are apparent as a result of adherence to tenets in explanation of the results. Most importantly, it should be emphasised that a hypothesis is there to be tested, not defended.
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Alimentación Animal/análisis , Interpretación Estadística de Datos , Suplementos Dietéticos/análisis , Enzimas/farmacología , Aves de Corral/fisiología , Alimentación Animal/estadística & datos numéricos , Animales , Pollos/fisiología , Dieta , Digestión , Endo-1,4-beta Xilanasas/farmacología , Enzimas/efectos adversos , Ácidos Grasos Volátiles , Polisacáridos/metabolismo , Prebióticos , Estudios Retrospectivos , Triticum/metabolismo , ViscosidadRESUMEN
While food losses (foods which were intended for human consumption, but which ultimately are not directly eaten by people) have been included in animal feed for millennia, the practice is all but banned in the European Union. Amid recent calls to promote a circular economy, we conducted a survey of pig farmers (n = 82) and other agricultural stakeholders (n = 81) at a UK agricultural trade fair on their attitudes toward the use of food losses in pig feed, and the potential relegalisation of swill (the use of cooked food losses as feed). While most respondents found the use of feeds containing animal by-products or with the potential for intra-species recycling (i.e. pigs eating pork products) to be less acceptable than feeds without, we found strong support (>75%) for the relegalisation of swill among both pig farmers and other stakeholders. We fit multi-hierarchical Bayesian models to understand people's position on the relegalisation of swill, finding that respondents who were concerned about disease control and the perception of the pork industry supported relegalisation less, while people who were concerned with farm financial performance and efficiency or who thought that swill would benefit the environment and reduce trade-deficits, were more supportive. Our results provide a baseline estimate of support amongst the large-scale pig industry for the relegalisation of swill, and suggest that proponents for its relegalisation must address concerns about disease control and the consumer acceptance of swill-fed pork.
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Agricultura , Alimentación Animal/provisión & distribución , Agricultores , Alimentos/estadística & datos numéricos , Reciclaje , Residuos Sólidos , Porcinos , Agricultura/legislación & jurisprudencia , Alimentación Animal/estadística & datos numéricos , Crianza de Animales Domésticos/legislación & jurisprudencia , Animales , Actitud , Agricultores/legislación & jurisprudencia , Agricultores/psicología , Agricultores/estadística & datos numéricos , Industria de Alimentos/legislación & jurisprudencia , Industria de Alimentos/métodos , Abastecimiento de Alimentos/legislación & jurisprudencia , Abastecimiento de Alimentos/normas , Humanos , Legislación Alimentaria , Opinión Pública , Reciclaje/legislación & jurisprudencia , Encuestas y Cuestionarios , Reino Unido/epidemiologíaRESUMEN
Anthropogenic food provisioning of wildlife can alter the frequency of contacts among hosts and between hosts and environmental sources of pathogens. Despite the popularity of garden bird feeding, few studies have addressed how feeders influence host contact rates and disease dynamics. We experimentally manipulated feeder density in replicate aviaries containing captive, pathogen-naive, groups of house finches (Haemorhous mexicanus) and continuously tracked behaviours at feeders using radio-frequency identification devices. We then inoculated one bird per group with Mycoplasma gallisepticum (Mg), a common bacterial pathogen for which feeders are fomites of transmission, and assessed effects of feeder density on house finch behaviour and pathogen transmission. We found that pathogen transmission was significantly higher in groups with the highest density of bird feeders, despite a significantly lower rate of intraspecific aggressive interactions relative to the low feeder density groups. Conversely, among naive group members that never showed signs of disease, we saw significantly higher concentrations of Mg-specific antibodies in low feeder density groups, suggesting that birds in low feeder density treatments had exposure to subclinical doses of Mg. We discuss ways in which the density of garden bird feeders could play an important role in mediating the intensity of Mg epidemics.This article is part of the theme issue 'Anthropogenic resource subsidies and host-parasite dynamics in wildlife'.