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The poultry sector is an important and vibrant segment of agriculture in Pakistan with a significant contribution to the national GDP (1.3%). Commercial poultry production in Pakistan started in the 1960's and has been providing a significant portion of daily proteins to the Pakistani population ever since. During its evolution the industry enjoyed promotional policies of the Government, but has faced several challenges such as disease outbreaks and retail price fluctuations. Despite its important role in the country's economy, not a single scientific study is available on its evolutionary history. The data available in this regard are scattered and lack reliability. This review is an effort to encompass the history of the overall growth of the poultry industry in Pakistan, its present status (2012 statistics) and future directions and challenges. This article may serve as the basic source of information on Pakistan's poultry industry achievements. It will also guide poultry experts and policy makers for developing strategic planning for further growth of the industry.
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A high-temperature procedure to hydrogenate diamond films using molecular hydrogen at atmospheric pressure was explored. Undoped and doped chemical vapour deposited (CVD) polycrystalline diamond films were treated according to our annealing method using a H2 gas flow down to ~50 ml∕min (STP) at ~850 °C. The films were extensively evaluated by surface wettability, electron affinity, elemental composition, photoconductivity, and redox studies. In addition, electrografting experiments were performed. The surface characteristics as well as the optoelectronic and redox properties of the annealed films were found to be very similar to hydrogen plasma-treated films. Moreover, the presented method is compatible with atmospheric pressure and provides a low-cost solution to hydrogenate CVD diamond, which makes it interesting for industrial applications. The plausible mechanism for the hydrogen termination of CVD diamond films is based on the formation of surface carbon dangling bonds and carbon-carbon unsaturated bonds at the applied tempera-ture, which react with molecular hydrogen to produce a hydrogen-terminated surface.
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Several mathematical or statistical and artificial intelligence models were developed to compare egg production forecasts in commercial layers. Initial data for these models were collected from a comparative layer trial on commercial strains conducted at the Poultry Research Farms, Auburn University. Simulated data were produced to represent new scenarios by using means and SD of egg production of the 22 commercial strains. From the simulated data, random examples were generated for neural network training and testing for the weekly egg production prediction from wk 22 to 36. Three neural network architectures-back-propagation-3, Ward-5, and the general regression neural network-were compared for their efficiency to forecast egg production, along with other traditional models. The general regression neural network gave the best-fitting line, which almost overlapped with the commercial egg production data, with an R(2) of 0.71. The general regression neural network-predicted curve was compared with original egg production data, the average curves of white-shelled and brown-shelled strains, linear regression predictions, and the Gompertz nonlinear model. The general regression neural network was superior in all these comparisons and may be the model of choice if the initial overprediction is managed efficiently. In general, neural network models are efficient, are easy to use, require fewer data, and are practical under farm management conditions to forecast egg production.
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Poultry growth is usually modeled with the Gompertz model or another nonlinear statistical model using average BW data over certain periods of time for a given strain of birds under specific farm management conditions. Constant selection in the genetic pool, nutritional factors, and environmental concerns, however, make such models limited in their utility because of the difficulty of fitting the growth curve across time, bird strains, and other determining variables. Moreover, generating data for every strain of birds under continually changing variables is difficult, expensive, and time consuming. The current model addresses 2 objectives: to simulate data using published literature for different growth periods, and to develop artificial intelligence models with various neural network architectures. By breaking down the actual broiler growth data into 5-d intervals, with known means and SD, normal distributions were generated for broiler growth using @Risk software. These simulated data were then used to recognize data patterns and model growth curves by using various neural networks. Three neural networks, namely, BackPropagation-3 (3 layers of back propagation, with each layer connected to the previous layer), BackPropagation-5 (5 layers of back propagation, with each layer connected to the previous layer), and Ward-5 (5 hidden slabs with various activation functions, using NeuroShell 2 Ward software) were used in this research. Once the networks were sufficiently trained, they were exposed to actual growth data to predict broiler growth over the next 50 d. The Back-Propagation-3 neural network gave the best fitting line, with predictions fitting tightly to the actual data points. The R2 was 0.998, and nearly perfect. The R2 for the BackPropagation-5 and Ward-5 neural networks were 0.967 and 0.973, respectively. To test the approach further, the same methodology was applied in guinea fowl growth prediction, resulting in R2 of 0.96 both for the general regression and Ward-5 neural networks.
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The objective of this study was to compare carcass characteristics of a newly introduced breed, the Waguli (Wagyu x Tuli), with the carcass characteristics of the Brahman breed. Brahman cattle are used extensively in the Southwest of the United States because of their tolerance to adverse environmental conditions. However, Brahman carcasses are discounted according to the height of their humps because of meat tenderness issues. The Waguli was developed in an attempt to obtain a breed that retained the heat tolerance of the Brahman but had meat quality attributes similar to the Wagyu. Twenty-four animals were used. Six steers from each breed were fed a 94% concentrate diet and 6 steers from each breed were fed an 86% concentrate diet. Eight steers, 2 from each group, were harvested after 128 d, after 142 d, and after 156 d on feed. Waguli steers had larger LM, greater backfat thickness, greater marbling scores, and greater quality grades than the Brahman steers (P < 0.05). The Japanese Wagyu breed is well known for its highly marbled and tender meat, and these traits are also present in the Waguli. The Waguli had significantly lower Warner-Bratzler shear force values than the Brahman steers after 7 and 10 d of postmortem aging (P < 0.05); this difference decreased after 14 d postmortem (P = 0.2), when tenderness of the slower aging Brahman had increased to acceptable levels. Toughness of the Brahman has been associated with high levels of calpastatin in Brahman muscle, and the Waguli LM had significantly less calpastatin activity (P = 0.02) at 0 h postmortem than the Brahman LM. At 0-h postmortem, the total LM calpain activity did not differ between the Brahman and Waguli (P = 0.57). Neither diet nor days on feed had any significant effect on the 0-h postmortem calpain or at 0-h postmortem calpastatin activity, nor an effect on Warner-Bratzler shear-force values. In conclusion, LM muscle from the Waguli steers had a high degree of marbling, lower shear force values, and low calpastatin activity, all of which are related to more tender meat.
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Alimentación Animal , Composición Corporal/fisiología , Proteínas de Unión al Calcio/metabolismo , Calpaína/metabolismo , Carne/normas , Músculo Esquelético/metabolismo , Tejido Adiposo/metabolismo , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Cruzamiento , Proteínas de Unión al Calcio/efectos adversos , Bovinos , Tecnología de Alimentos , Masculino , Músculo Esquelético/anatomía & histología , Fenotipo , Distribución Aleatoria , Factores de TiempoRESUMEN
Egg price forecasting of shelled eggs is a complex problem. Traditionally, future egg price has been predicted using a combination of regression analysis and experienced-based intuition to build a model, which is then fine-tuned to prevalent market conditions. Even after collecting reliable and expensive data, the subsequent analysis, in many cases, does not produce a high confidence to explain the variations in egg price. In the current project, a different approach using neural networks was used to forecast egg price. A neural network is a mathematical model of an information-processing structure that is loosely based on our present understanding of the working of human brain. An artificial neural network consists of a large number of simple processing elements connected to each other in a network. Urner Barry egg quotes from 1991 to 2002 as well as number of hens, egg storage capacity, and number of eggs placed for hatching from the USDA databases (1993 to 2000) were used to forecast egg price. Regression analysis explained only 37% of the variation in egg price due to the above-mentioned 3 factors. Neural networks, on the other hand, recognize the pattern in previous years' egg prices and then predict the future price more efficiently. The 3 networks used in this research (Ward, back-propagation, and general regression neural networks) fit the forecast line more tightly to the previous year's egg price line than did regression analysis. In the case of general regression neural networks, the R2 value was as high as 60%. Results suggest that neural networks may be a more reliable method of egg price forecasting than simple regression analysis if reliable data are collected and manipulated for such models.
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Huevos/economía , Predicción/métodos , Agricultura/economía , Animales , Pollos , Modelos Lineales , Modelos Económicos , Redes Neurales de la Computación , Factores de TiempoRESUMEN
Ten healthy Labrador Retrievers (4 females and 6 males aged 3-6.5 years [mean, 4.5 years]) training with a professional trainer were studied. The dogs were in training during the entire study. Dogs were monitored within 5 minutes after retrieving birds on land and in water on 2 consecutive days during training and on 2 consecutive days at the Atlanta Retriever Club Fall Field Trial. Baseline samples were taken in the morning on a separate day before the dogs were loaded onto a truck. Venous samples were analyzed with a portable blood analyzer. Measurements included hematocrit, sodium, potassium, chloride, blood urea nitrogen (BUN), glucose, lactate, blood pH, Pco2, Po2, HCO3, and TCO2 plus rectal temperature, pulse rate, and respiratory rate. Ambient temperatures were recorded. Distances and times were estimated. Compared to baseline, significant increases occurred in rectal temperature, pulse rate, respiratory rate, chloride, lactate, and pH postexercise (P < .05): sodium, potassium, BUN, Pco2, and TCO2 were significantly decreased postexercise. Blood pH was markedly higher after retrieves on land than after retrieves in water. Estimated mean speeds were 11.4 mph (18.3 km/h) during a triple retrieve on land and 5.6 mph (9.0 km/h) during a retrieve in water. Maximal ambient temperatures were 84-86 degrees F (29-30 degrees C). In summary, Labrador Retrievers training with a professional trainer had evidence of hyperthermia, respiratory alkalosis, hypocapnia, and mild metabolic acidosis monitored within 5 minutes postexercise during training and field trial competition when maximal ambient temperatures were 85 degrees F (29 degrees C). The results provide a baseline against which physiologic responses of dogs with poor performance can be compared.
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Perros/fisiología , Condicionamiento Físico Animal/fisiología , Animales , Análisis Químico de la Sangre/veterinaria , Análisis de los Gases de la Sangre/veterinaria , Temperatura Corporal , Perros/sangre , Femenino , Frecuencia Cardíaca , Hematócrito/veterinaria , Masculino , Linaje , Valores de Referencia , RespiraciónRESUMEN
The effect of freezing and bacterial growth on the discoloration of beef was assessed by measuring myoglobin derivatives myoglobin (MB), oxymyoglobin (MBO(2)), and metmyoglobin (METMB) on the surfaces of fresh and frozen-thawed packaged beef cuts stored at 2 degrees C and analyzed after 0, 3, 6, 9, and 12 days of storage. MB, MBO(2), and METMB concentrations were measured spectrophotometrically. Frozen-thawed beef samples experienced less "blooming" (conversion of MB to MBO(2)) and more rapid discoloration than fresh cuts during storage. By day 3, >20% METMB was formed in the frozen-thawed samples, whereas the fresh samples reached this value after day 6 of storage. The rates of MB oxidation were similar (P > 0.05) for sterile and frozen-thawed inoculated (Pseudomonas fluorescens at a rate of 1.5 colony forming units/cm(2).cm(2) area) samples from day 0 through day 6 of storage. For storage periods of less than a week, bacterial growth is not a major cause of meat discoloration. After day 6, the high bacterial growth rate resulted in a rapid increase in METMB formation. Possible mechanisms for MB oxidation in frozen-thawed beef are suggested.
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Carne/análisis , Carne/microbiología , Mioglobina/análisis , Animales , Bovinos , Recuento de Colonia Microbiana , Manipulación de Alimentos , Embalaje de Alimentos , Congelación , Metamioglobina/análisis , Pseudomonas fluorescens/crecimiento & desarrolloRESUMEN
OBJECTIVE: To determine the aetiology, frequency, presentation, and outcome of blunt cervicocerebral arterial dissection presentations. PATIENTS AND METHODS: Cases were retrospectively identified through the stroke registers at Royal Melbourne Hospital (a tertiary teaching hospital) and Geelong Hospital (a regional referral centre). Medical notes were then reviewed. RESULTS: A total of 18 cases were identified, with ages ranging from 28 to 53 years. Fifty five per cent of the injuries sustained were to the internal carotid artery and 45% to the vertebral artery. The majority of the injuries were either spontaneous or associated with trivial forces. Other causes included motor vehicle accidents, falls, and cervical manipulations. Fifty five per cent of patients complained of significant neck pain before presentation. Most patients had delayed presentations, with only 39% presenting on the day of the incident. Seventy eight per cent presented with a neurological deficit. Initial computed tomography was normal in 71% of patients. The majority of patients were managed with anticoagulation, and had minimal functional deficit on discharge. Other treatment modalities included surgery (one patient) and thrombolysis (two patients). One patient was managed conservatively. CONCLUSIONS: The incidence of blunt cervicocerebral arterial dissection is unknown; however it is an uncommon diagnosis. The most common presentation is that of a delayed neurological event. Initial brain computed tomography is usually normal. Minimal adverse outcomes at discharge were noted in patients treated with anticoagulation only.
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Disección de la Arteria Carótida Interna/epidemiología , Disección de la Arteria Vertebral/epidemiología , Heridas no Penetrantes/epidemiología , Adulto , Disección de la Arteria Carótida Interna/diagnóstico por imagen , Disección de la Arteria Carótida Interna/fisiopatología , Disección de la Arteria Carótida Interna/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sistema de Registros , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Disección de la Arteria Vertebral/diagnóstico por imagen , Disección de la Arteria Vertebral/fisiopatología , Disección de la Arteria Vertebral/terapia , Victoria/epidemiología , Heridas no Penetrantes/etiología , Heridas no Penetrantes/fisiopatología , Heridas no Penetrantes/terapiaRESUMEN
An experiment was conducted to determine the effect of feeding method (constant vs variable) and method of formulation (lysine vs protein) on the performance and profits of first cycle, phase 2 DeKalb Delta hens from 40 to 52 wk of age as influenced by egg and feed prices. Treatments 1 to 5 were formulated based on lysine to contain 0.65 to 0.81% TSAA and fed continuously regardless of feed consumption (constant feeding). Treatments 6 to 10 and 11 to 15 were formulated based on lysine to supply 570 to 650 mg TSAA and protein to supply 580 to 660 mg TSAA per hen per d, respectively, and fed based on feed intake. Dietary TSAA level had no overall significant effect on feed consumption, egg production, egg weight, mortality, or body weight. Hens fed diets using the constant method of feeding had significantly higher egg production, egg weight, egg specific gravity, and body weight than hens fed diets formulated based on lysine or protein using the variable method of feeding. When the treatments in the two variable feeding methods were compared, feed consumption was significantly higher for hens fed diets formulated based on protein whereas egg production, egg weight, egg specific gravity, and body weight were not different. It was concluded that method of formulation (lysine vs protein) and TSAA levels required for maximum profits can vary from at least 570 to 821 mg per hen per d depending upon energy and protein cost.