• Title/Summary/Keyword: Models, animal

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Modeling and Forecasting Livestock Feed Resources in India Using Climate Variables

  • Suresh, K.P.;Kiran, G. Ravi;Giridhar, K.;Sampath, K.T.
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.4
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    • pp.462-470
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    • 2012
  • The availability and efficient use of the feed resources in India are the primary drivers to maximize productivity of Indian livestock. Feed security is vital to the livestock management, extent of use, conservation and productivity enhancement. Assessment and forecasting of livestock feed resources are most important for effective planning and policy making. In the present study, 40 years of data on crop production, land use pattern, rainfall, its deviation from normal, area under crop and yield of crop were collected and modeled to forecast the likely production of feed resources for the next 20 years. The higher order auto-regressive (AR) models were used to develop efficient forecasting models. Use of climatic variables (actual rainfall and its deviation from normal) in combination with non-climatic factors like area under each crop, yield of crop, lag period etc., increased the efficiency of forecasting models. From the best fitting models, the current total dry matter (DM) availability in India was estimated to be 510.6 million tonnes (mt) comprising of 47.2 mt from concentrates, 319.6 mt from crop residues and 143.8 mt from greens. The availability of DM from dry fodder, green fodder and concentrates is forecasted at 409.4, 135.6 and 61.2 mt, respectively, for 2030.

ALTERATION MODELS TO PREDICT LACTATION CURVES FOR DAIRY COWS

  • Sudarwati, H.;Djoharjani, T.;Ibrahim, M.N.M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.8 no.4
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    • pp.365-368
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    • 1995
  • Lactation curves of dairy cows were generated using three models, namely; incomplete gamma function (model 1), polynomial inverse function (model 2) and non-linear regression (model 3). Secondary milk yield data of 27 cows which had completed 6 lactations were used in this study. Milk yield records (once a week) throughout the lactation and from the first three months of lactation were fitted to the models. Estimation of total milk yield by model 3 using the data once a week throughout the lactation resulted in smaller % bias and standard error than those generated from model 1 and 2. But, model 2 was more accurate in predicting the 305-day milk yield equivalent closer to actual yields with smaller bias % and error using partial records up to 3 months. Also, model 2 was able to estimate the time to reach peak yield close to the actual data using partial records and model 2 could be used as a tool to advise farmers on appropriate feeding and management practices to be adopted.

ENERGY UTILIZATION MODELS OF CATTLE GRAZING IN OIL PALM PLANTATIONS II. VALIDATION OF MODELS

  • Dahlan, I.;Mahyuddin, M.D.;Yamada, Y.
    • Asian-Australasian Journal of Animal Sciences
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    • v.8 no.1
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    • pp.67-73
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    • 1995
  • This study showed that models of energy utilization(EU) developed for grazing cattle in oil palm plantations is valid as the simulated results shows an agreement with actual data of calves and cows body weight changes collected from Brahman x Kedah-Kelantan herd on Pengeli Timor Plantation. Simulation runs on EU models demonstrated that the growth pattern of male and female calves and the weight changes of cows are similar and showed slight variation from the actual data but with no significant difference (p > 0.05). Parameter values such as metabolizability (q), dry matter digestibility(DMD) of herbage and voluntary intake of grazing cattle (VIG) and faecal output/body weight ratio (F) of the animals which were collected from the field are essential in bearing the pattern of body weight changes of the calves and cows in relation to increase in time, physiological status and quality of herbage grazed by these animals in the production system. The EU models is suitable for determining the metabolizable energy requirements and to predict the production of grazing cattle according to quality of the feed on offer.

ENERGY UTILIZATION MODELS OF CATTLE GRAZING IN OIL PALM PLANTATIONS I. DEVELOPMENT OF MODELS

  • Dahlan, I.;Yamada, Y.;Mahyuddin, M.D.
    • Asian-Australasian Journal of Animal Sciences
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    • v.8 no.1
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    • pp.59-66
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    • 1995
  • Energy obtained by grazing cattle in oil palm plantations is usually used for maintenance of body functions, the construction of body tissues and pregnancy, the synthesis of milk and the conversion to mechanical energy used for activities such as walking, eating and others. In this study, attempt was made to estimate metabolizable energy (ME) requirement of grazing cattle. Models of ME requirement (MER) for maintenance, gain, pregnancy, lactation and activities were developed. ME system and units were used because of wide recognition. Estimation of ME intake in grazing cattle was expressed as MEVI = $14.58{\times}VI{\times}DMD$, and under grazing condition MEVI = $MER_i$. MER was expressed as a function of net energy(NER, MJ) required for the i'th body function. Coefficient of efficiency for conversion of ME into net energy(ki) was adopted from literatures. Quantifying of ME requirement for Kedah-Kelantan cattle under grazing condition was made by using equation MERM = NEM / kn. The estimated values of MER for Kedah-Kelantan cattle is quite reasonable if compared with other estimates as reported in literatures from stall-fed animals. Dynamic MER models for grazing herd was developed in order to estimate ME requirement for maintenance and productions. These ME requirement models can be used for prediction of energy utilization pattern of the herd in the grazing systems.

The Chicken Aorta as a Simulation-Training Model for Microvascular Surgery Training

  • Ramachandran, Savitha;Chui, Christopher Hoe-Kong;Tan, Bien-Keem
    • Archives of Plastic Surgery
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    • v.40 no.4
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    • pp.327-329
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    • 2013
  • As a technically demanding skill, microsurgery is taught in the lab, in the form of a course of variable length (depending on the centre). Microsurgical training courses usually use a mixture of non-living and live animal simulation models. In the literature, a plethora of microsurgical training models have been described, ranging from low to high fidelity models. Given the high costs associated with live animal models, cheaper alternatives are coming into vogue. In this paper we describe the use of the chicken aorta as a simple and cost effective low fidelity microsurgical simulation model for training.

The Development of Predictive Growth Models for Total Viable Cells and Escherichia coli on Chicken Breast as a Function of Temperature

  • Heo, Chan;Kim, Ji-Hyun;Kim, Hyoun-Wook;Lee, Joo-Yeon;Hong, Wan-Soo;Kim, Cheon-Jei;Paik, Hyun-Dong
    • Food Science of Animal Resources
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    • v.30 no.1
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    • pp.49-54
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    • 2010
  • The aim of this research was to estimate the effect of temperature and develop predictive models for the growth of total viable cells (TVC) and Escherichia coli (EC) on chicken breast under aerobic and various temperature conditions. The primary models were determined by Baranyi model. The secondary models for the specific growth rate (SGR) and lag time (LT), as a function of storage temperature, were developed by the polynomial model. The initial contamination level of chicken breasts was around 4.3 Log CFU/g of TVC and 1.0 Log CFU/g of E. coli. During 216 h of storage, SGR of TVC showed 0.05, 0.15, and 0.54 Log CFU/g/h at 5, 15, and $25^{\circ}C$. Also, the growth tendency of EC was similar to those of TVC. As storage temperature increased, the values of SGR of microorganisms increased dramatically and the values of LT decreased inversely. The predicted growth models with experimental data were evaluated by $B_f$, $A_f$, RMSE, and $R^2$. These values indicated that these developed models were reliable to express the growth of TVC and EC on chicken breasts. The temperature changes of distribution and showcase in markets might affect the growth of microorganisms and spoilage of chicken breast mainly.

Variance Components and Genetic Parameters Estimated for Fat and Protein Content in Individual Months of Lactation: The Case of Tsigai Sheep

  • Oravcova, Marta
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.2
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    • pp.170-175
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    • 2016
  • The objective of this study was to assess variance components and genetic parameters for fat and protein content in Tsigai sheep using multivariate animal models in which fat and protein content in individual months of lactation were treated as different traits, and univariate models in which fat and protein content were treated as repeated measures of the same traits. Test day measurements were taken between the second and the seventh month of lactation. The fixed effects were lactation number, litter size and days in milk. The random effects were animal genetic effect and permanent environmental effect of ewe. The effect of flock-year-month of test day measurement was fitted either as a fixed (FYM) or random (fym) effect. Heritabilities for fat content were estimated between 0.06 and 0.17 (FYM fitted) and between 0.06 and 0.11 (fym fitted). Heritabilities for protein content were estimated between 0.15 and 0.23 (FYM fitted) and between 0.10 and 0.18 (fym fitted). For fat content, variance ratios of permanent environmental effect of ewe were estimated between 0.04 and 0.11 (FYM fitted) and between 0.02 and 0.06 (fym fitted). For protein content, variance ratios of permanent environmental effect of ewe were estimated between 0.13 and 0.20 (FYM fitted) and between 0.08 and 0.12 (fym fitted). The proportion of phenotypic variance explained by fym effect ranged from 0.39 to 0.43 for fat content and from 0.25 to 0.36 for protein content. Genetic correlations between individual months of lactation ranged from 0.74 to 0.99 (fat content) and from 0.64 to 0.99 (protein content). Fat content heritabilities estimated with univariate animal models roughly corresponded with heritability estimates from multivariate models: 0.13 (FYM fitted) and 0.07 (fym fitted). Protein content heritabilities estimated with univariate animal models also corresponded with heritability estimates from multivariate models: 0.18 (FYM fitted) and 0.13 (fym fitted).

Use of Animals for Nursing Research in Korea (동물 실험을 적용한 국내 간호 연구 동향 분석)

  • Yoo, Hae Young
    • Journal of Korean Biological Nursing Science
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    • v.17 no.4
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    • pp.324-330
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    • 2015
  • Purpose: The purpose of this study was to analyze the trends in Korea of nursing research using animals. Methods: 45 articles were reviewed with descriptive statistics from 2000 to 2015. Results: Nearly 50% of the studies were supported by research funds. Most of the animal species in the studies were rats (81.1%) and mice (15.6%). The major animal models for human disease were cerebrovascular diseases (24.4%), skin problems (17.8%), and nerve injuries (15.5%). Immunohistochemistry (24.3%) was mainly used as an experimental technique. The main intervention and treatments used in the studies were chemical treatments, exercise and surgery. Conclusion: In this review, relevant results were described to identify the trends of nursing research using animal experimentation in Korea. Expansion of various nursing research using animal models can be required for gaining knowledge applicable to the same conditions in humans.

A review of the effects of environmental enrichment on stroke in animal experimental models (뇌졸중 동물 실험 모델에서 환경 강화 효과에 대한 종설)

  • Lee, Kyoung-Hee;Hwang, Ki-Chul
    • Journal of Digital Convergence
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    • v.12 no.8
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    • pp.423-430
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    • 2014
  • The purpose of this article is to present the environmental enrichment(EE) method used to improve the functional recovery and change of brain plastic in animal experimental models of stroke. In animal experimental models of stroke, the environmental enrichment is effective in altering the morphological, biochemical and behavioral characteristics of the brain and thereby improving the functional outcomes. In this review article, we address the effects of EE in achieving a functional recovery in animal experimental models of stroke, thus attempting to describe them in patients with stroke from both occupational and rehabilitation perspectives.

Animal Models for Development of Cognitive Enhancers and Action of Drugs

  • Nomura, Yasuyuki
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1995.04a
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    • pp.35-36
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    • 1995
  • To gain insight into the etiological mechanism of dementia and to develop clinically effective congnitive enhancers, it is required to prepare animal models with symptoms and mechanism resemble to that in human. Dementia is mainly classified into two types : senile type of Alzheimer's disease (STAD) and cerebral ischemia-induced one. As animal models of cerebral ischemia, a couple of types in rats have been introduced : one is the occlusion of bilateral carotid arteries-induced forebrain/global ischemia and the other is the occlusion of middle cerebral arteries-induced focal/regional ischemia.

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