Hiroyuki Hirooka's research while affiliated with Kyoto University and other places

Publications (138)

Article
Heart rate variability (HRV), heart beat-to-beat variations, is a measure of cardiac autonomic functions, and HRV monitoring using sensor technology can be a non-invasive way to assess stress of animals. The objective of this study was to investigate the effect of dietary vitamin A (VA) restriction to enhance beef quality on the physiological statu...
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We investigated the effects of supplementary calcium salt of fatty acid (CSFA) from linseed oil with different oil adsorbents on in vitro gas production and rumen fermentation characteristics in barley substrate condition. A non‐supplementation treatment (CONT) and treatments of six products, CSFA without oil adsorbent (2.1 fatty acid/Ca molar rati...
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This study aimed to determine the taxonomic and functional characteristics of the Japanese Black (JB) steer rumen microbiome. The rumen microbiomes of six JB steers (age 14.7 ± 1.44 months) and six JB sires × Holstein dams crossbred (F1) steers (age 11.1 ± 0.39 months), fed the same diet, were evaluated. Based on 16S rRNA gene sequencing, the beta...
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Body condition score (BCS) is a proxy for evaluating body fat reserves. However, monitoring BCS is a time-consuming and subjective task. Thus, we aimed to develop a method for estimating the BCS of beef cows using three-dimensional (3D) body features of cows’ rump area derived from 3D camera data. Three-dimensional surface data of the rump area fro...
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Although sex sorted sperm technology is commercially available in Japan, adoption of the technology has been limited in dairy farms due to high production cost, low conception rate and incomplete sexing accuracy. In this study, the base scenario with unsexed semen and four alternative scenarios were compared using a bio-economic and environment sim...
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In recent, animal industries are faced with the challenge to meet economic viability for animal production while reducing the environmental impacts. For the implementation of the environmental abatement strategies, it is important as the first step to quantify the cost-effectiveness of such strategies. This study showed the rationale of the two typ...
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To quantify what attributes of wastewater treatment systems are preferred by pig farmers, a discrete choice experiment was conducted by a questionnaire survey of pig farmers in four prefectures, Japan, in the present study. Farmers were offered a series of choice sets including the following five attributes of wastewater treatment systems: ability...
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Heart rate variability (HRV) is the heart beat-to-beat variation under control of the cardiovascular function of animals. Under stressed conditions, cardiac activity is generally regulated with an upregulated sympathetic tone and withdrawal of vagal tone; thus, HRV monitoring can be a non-invasive technique to assess stress level in animals especia...
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The objective of the present study was to develop a deterministic simulation model for evaluating the reproductive performance of Thoroughbred mares. As an application, the model was used to estimate the herd level asymptotic foaling percentage (AFP) for evaluating the performance of mares in stabilized mare herds using the convergent method for es...
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Evaluation of animal behavior provides information on health and well-being in animals. In this preliminary study, we investigated the effectiveness of an accelerometry approach to evaluate changes in health status of cattle by combining physical activity quantified by dynamic body acceleration (DBA) and qualitative behavioral classification data....
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The objective of this study was to develop mathematical equations for describing the change in marbling in Japanese Black steers using longitudinal measurements. Serial ultrasound measurements were taken at 14, 16, 20, and 26 months of age and analyzed using an image analysis software. The longitudinal marbling measurements from the ultrasound imag...
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Calcium salts of long-chain fatty acids (CSFA) from linseed oil have the potential to reduce methane (CH 4 ) production from ruminants; however, there is little information on the effect of supplementary CSFA on rumen microbiome as well as CH 4 production. The aim of the present study was to evaluate the effects of supplementary CSFA on ruminal fer...
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The use of environmentally friendly diets (e.g., low-protein diets supplemented with synthetic amino acids for balancing amino acid contents) in animal production systems is receiving attention as a method to reduce greenhouse gas (GHG) emissions. The objective of the present study was to quantify how dairy and pig farmers have the preference for s...
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Genomic imprinting should be considered in animal breeding systems to avoid lead in bias in genetic parameter estimation. The objective of this study was to clarify the effects of pedigree information on imprinting variances for carcass traits and fatty acid composition in Japanese Black cattle. Carcass records [carcass weight, rib eye area, rib th...
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Wine lees are by-products of wine-manufacturing, but the usefulness as animal by-product feed has not yet been revealed. The present study was aimed to investigate the usability of wine lees as feed for ruminants in fattening conditions by in vitro and in vivo trials. In in vitro experiments (in vitro I and II), the following four treatments were p...
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This study was aimed at investigating the local livestock biomass volume for dairy farms in Town A, located in eastern Hokkaido, Japan, and at presenting a model of a biogas plant that enables maximizing the use of the available livestock biomass. Using a dairy farm with 250 animals in Town A as a model for a biogas plant based on dry-type methane...
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Four Thai native bulls were used to evaluate the availability of mother liquor (ML), by‐product of monosodium glutamate, as a replacement of soybean meal (SBM) consisting of 10% in concentrate. The SBM was replaced by the ML at 0% (C), 20% (T1), 40% (T2), and 60% (T3), and the experiment was a randomized block design experiment. The animals were fe...
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The objective of this study was to estimate genetic parameters for first calving reproductive traits and growth curve characteristics in Japanese Black cattle. The Gompertz growth function was fitted to body weight–age data to obtain the mature weight (MWT) and rate of maturing (ROM) of cows. Data of reproductive traits including the first service...
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Recent developments of small electronic instruments have enabled the classification of animal behavior using simultaneous measurements of various bio-logging data such as acceleration, magnetism, and angular velocity. Following technological progress, studies on the behavioral classification of ruminants combining measurements based on acceleromete...
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Experimental and comparative studies suggest that the striped coats of zebras can prevent biting fly attacks. Biting flies are serious pests of livestock that cause economic losses in animal production. We hypothesized that cows painted with black and white stripes on their body could avoid biting fly attacks and show fewer fly-repelling behaviors....
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In Southwestern China, dairy farms utilized by-product feeds in dairy production and surplus calves were kept for producing beef as a by-product. However, it is unclear how the environmental impacts are in such dairy production system. This study evaluated, for the first time, the global warming potential (GWP), acidification potential (AP), eutrop...
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In recent years, livestock production has to ensure not only productivity and economics but also animal welfare. This review summarized the effects of animal welfare on beef productivity and the consumers’ demand in beef food chain based on European researches mainly. The management practices related with animal welfare can improve beef productivit...
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Variances caused by the differential expression of paternally and maternally imprinted genes controlling carcass traits in Japanese Black cattle were estimated in this study. Data on marbling score (BMS), carcass weight, rib thickness, rib‐eye area (REA) and subcutaneous fat thickness (SFT) were collected from a total of 13,115 feedlot steers and h...
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The objective of this study was to evaluate the environmental impacts of the intensive dairy farms in Songming region in Yunnan Province in Southwestern China. A total of 36 dairy farms with utilization of by-product feeds and high fertilizer application were investigated in the study site. The life cycle assessment (LCA) methodology was used to qu...
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In vitro fermentation experiment and in vivo metabolic experiment were conducted to investigate the effects of sake lees made from steamed rice on digestion, ruminal fermentation, nitrogen balance and blood metabolites in wethers fed high concentrate diets. Rolled barley was replaced with soybean meal (SBM), dried sake lees (SLd) and wet sake lees...
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Mother liquor (ML) is monosodium glutamate by‐product and contains much crude protein (CP). The objective of this study was to investigate the effect of supplementation of two types of MLs having different chemical compositions on in vitro ruminal fermentation characteristics. ML1 had 74% organic matter (OM) and 70% CP and ML2 had 85% OM and 83% CP...
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Heart rate variability (HRV) analysis is a widely used technique to assess sympatho-vagal regulation in response to various internal or external stressors. However, HRV measurements under free-moving conditions are highly susceptible to subjects’ physical activity levels because physical activity alters energy metabolism, which inevitably modulates...
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Animal welfare and environmental impacts have been emphasized in the sustainable production of livestock. Labels are useful tools for clearly providing such attribute information to consumers. The aim of this study was to evaluate how human values influence consumer segments for beef with information on animal welfare and environmentally friendly p...
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The beef fattening production system in Japan typically uses a large amount of imported feed under housing management. Since this system has several economic and environmental problems, the grazing fattening system using Japanese Brown cattle (a local breed which is thought to be suitable for grazing system) has recently been receiving attention. H...
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The sizes of body parts often co-vary through exponential scaling, known as allometry. The evolution of allometry is central to the generation of morphological diversity. To make inferences regarding the evolved responses in allometry to natural and artificial selection, we compared allometric parameters (slope and intercept) among seven species an...
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Increase in production of whole crop rice silage is expected to improve the food self-sufficiency rate in Japan. Introduction of forage rice cultivation under late seeding conditions into the rice-wheat cropping systems is considered a means of cultivation management for high land use efficiency, high productivity, and reduction in cost and labor....
Article
Four Thai native cattle were used in a 4 × 4 Latin square design experiment to evaluate the availability of desalted mother liquor (DML) as replacement of salt in concentrate. Each cattle was assigned to one of the following concentrate feeding treatments: C1, 1% NaCl was added as salt; C2, 2% NaCl was added as salt; D1, 1% NaCl was replaced by DML...
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Four Thai native steers were used to determine the adequate levels of supplementary desalted mother liquor (DML) for energy and nitrogen balances and ruminal fermentation. The crude protein and sodium chloride contents of DML were 25.5% and 60.3% on a dry matter (DM) basis, respectively. A 4 × 4 Latin square design experiment was conducted by addin...
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The estimation of energy expenditure (EE) of grazing animals is of great importance for efficient animal management on pasture. In the present study, a method is proposed to estimate EE in grazing animals based on measurements of body acceleration of animals in combination with the conventional Agricultural and Food Research Council (AFRC) energy r...
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The objective of this study was to evaluate environmental impacts of a year-round-grazing fattening system in a subtropical region, Okinawa, Japan, using the life cycle assessment (LCA). The fattening system for Japanese Brown steers was an intensive rotational grazing with by-product feeds (brewers grain and broken rice) as total mixed rations (TM...
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The improvement of farm animal welfare through management practices has become important despite the fact that there is a conflict between animal welfare and production efficiency. It may be possible to find associations between production and management practices related to animal welfare, such as management strategies to enhance both production a...
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Biochemical values and mineral concentrations in blood plasma were investigated to evaluate the statuses of health and mineral nutrition among yaks in Mustang District, Nepal. In total, 118 plasma samples of female yaks collected in April and September/October of 2013-2015 were offered. Seventy-four percent of yaks showed lower plasma total-cholest...
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We examined the in vitro fermentation characteristics and in situ dry matter (DM) and crude protein (CP) degradability of tamarind kernel powder extract residue (TKPER), a by-product of polysaccharides thickener processing. Two types of TKPER (I and II), of which the CP and neutral detergent fiber organic matter basis contents (%) were 41.4 and 42....
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The objective of this study was to investigate the relationship between consumers’ purchasing consciousness and the purchasing price of beef, using the results of an internet questionnaire survey focused on female consumers. The following three factors were obtained from the analysis: (1) intrinsic quality value, which is associated with the physic...
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Objective This study was to examine in vivo digestibility, nitrogen balance and ruminal fermentation of tamarind (Tamarind indica) kernel powder extract residue (TKPER) compared to soybean products and by-products in wethers. Methods Four wethers with initial body weight (BW) of 51.6±5.5 kg were assigned in a 4×4 Latin square design to investigate...
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The objectives of this study were to evaluate the environmental and economic impacts of year-round-grazing systems and a conventional housing system for Japanese Brown fattening steers by the life cycle assessment (LCA) method. Four treatments were designed in this study; grazing fattening without feed rice (G group), grazing fattening with feed ri...
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This study was conducted to determine the effects of dietary soybean curd residue (SCR) and soy sauce cake (SSC) on the growth performance, carcass traits and physiochemical and intramuscular fatty acid (FA) characteristics in Japanese Black steers. Ten steers (29.7 ± 0.3 months old, 856.6 ± 24.4 kg body weight) were assigned to either treatment C,...
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The Japanese Agricultural Systems Society was established in April, 1984 and the journal of the Society has published across a wide range of disciplines and at various levels of detail concerning agricultural systems since September, 1984. The Society and the journal have emphasized the need for interdisciplinarity in agriculture and aimed to integ...
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The objectives of this study were to estimate and evaluate potassium (K) and magnesium (Mg) budgets and flows of animal production in the basin of Dianchi Lake, China. Feed sampling and farmer interviews were conducted in field surveys. The supplies of K and Mg from local and external feeds and the retention, production and excretion of animals wer...
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The factors influencing the priority of access to food and the effects of the priority of access to food on their carcass traits were analyzed for Japanese Black (Wagyu) cattle in a semi-intensive fattening production system. The records of 96 clinically healthy steers and heifers were analyzed. The calves at ∼3 to 4 months of age were allocated to...
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Estimating the energy expenditure of farm animals at pasture is important for efficient animal management. In recent years, an alternative technique for estimating energy expenditure by measuring body acceleration has been widely performed in wildlife and human studies, but the availability of the technique in farm animals has not yet been examined...
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We assessed the nitrogen (N) and phosphorus (P) flows in intensified livestock production systems by investigating nutrient budgets and cycling in the basin of Dianchi Lake, one of the most eutrophic lakes in China. We conducted field surveys based on feed samplings and interviews of livestock farmers. The N and P in local and external feeds, anima...
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To investigate the effects of total mixed ration (TMR) silage, which contained brewers grain and rice straw as a substitute for conventional concentrate on feed intake and milk production in middle-to-late lactation buffaloes, four multiparous Murrah buffaloes were assigned to a 3 × 3 Latin square design experiment. The TMR silage, which had higher...
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| Subclinical ketosis is one of the most prevalent metabolic disorders that usually occurs in cows during the first weeks of lactation. This study investigated the relationship between energy level, body condition score and silage butyric acid with incidence of subclinical ketosis (SCK) in dairy cows during the first month of postpartum. Fifty heal...
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Four wethers were used in a 4 × 4 Latin square design experiment to evaluate the availability of two types of winery wastes, winery sediment and grape pomace, as ruminant feeds possessing antioxidant activities. Each wether was assigned to one of the following four treatments: (i) 75 g/kg winery sediment (WS) on a dry matter (DM) basis; (ii) 166 g/...
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The objectives of this study were to evaluate and compare the environmental impacts and feed costs of two beef-fattening experiments using linseed oil soap fatty acids (LS) by the life cycle assessment (LCA) method. Crossbred heifers between Japanese Black sires and Holstein dams were used for two fattening experiments. In the first experiment, thr...
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Four wethers were used in a 4 × 4 Latin square design experiment to evaluate in vivo digestibility of total mixed ration (TMR) silage with food by-products for dairy cows, and the ruminal condition and nitrogen (N) balance were examined. Five by-products (i.e. potato waste, noodle waste, soybean curd residue, soy sauce cake and green tea waste) wer...
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Postnatal mortality (PM) of calves is an economically important trait, because a high mortality rate of calves decreases farm income and significantly increases production costs. In spite of the economic importance of PM, genetic studies on PM have been scarce for Japanese Black cattle. The objectives of this study were to estimate the direct and m...
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The objective of this study was to develop equations to predict carcass tissue weights and percentages and boneless carcass non-trimmed cut weights by using the cold carcass weight (CCW) and three other traits at the 6-7th rib section, which are routinely collected in carcass markets in Japan. Carcasses from 94 Japanese Black steers were used for t...
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Ketosis is a metabolic disorder which usually occurs in cows during1 early lactation in both, industrialized and developing countries. There are no data available about the prevalence of ketosis in major dairy producing provinces in Iran. This study investigated the prevalence of ketosis among 1,002 Iranian Holstein cows from days 5 to 50 post calv...
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Three types of bamboo pellets as a ruminant feed: P1 (ground bamboo (GB) cultured with the fungus Ceriporiopsis subvermispora (CGB) : soybean curd residue (T) : soy sauce cake (S) in a 5:4:1 ratio on a dry matter (DM) basis); P2 (GB : T : S = 5:4:1 on a DM basis); and P3 (CGB : T : S = 5.5:0.8:3.7 on a DM basis) were prepared. Four wethers were ass...
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Domestication of animals has resulted in phenotypic changes by means of natural and human-directed selection. Body composition is important for farm animals because it reflects the status of energy reserves. Thus, there is the possibility that farm animals as providers of food have been more affected by human-directed selection for body composition...
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The effects of changes in culling parity of cows and diet composition on economic and environmental outputs in Japanese beef cow–calf production systems were deterministically analyzed using a herd model simulation. The model simulated the annualized net revenue as an economic indicator and the overall environmental index derived from a life cycle...
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Four wethers were used in a 4 × 4 Latin square design experiment to evaluate the applicability of two types of total mixed ration (TMR) silage with food by-products. Four food by-products (i.e., potato waste, soy sauce cake, soybean curd residue and noodle waste) were obtained and mixed with commercial concentrate (CC) as TMR silage. The two types...
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The suitability of anaerobically-digested manure (ADM) from a biogas plant, as an alternative to chemical fertilizers for rice cultivation was evaluated by a long-term study. At the standard nitrogen (N) application rate (10 g m -2), the aboveground biomass, N uptake, and grain yield in rice plots with ADM application (MF) were not significantly di...
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A pilot study was conducted to evaluate the suitability of stable isotope analysis for inferring the feeding histories of cattle fed known feeds. Stable isotope ratios of carbon and nitrogen (δ13C and δ15N) were measured in meat and hair from cattle and in their feeds at five farms in different regions of Japan, and the correlations of the isotope...
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An experiment was conducted using 17 male buffalo calves to assess the effects of plane of nutrition on slaughtering traits and meat characteristics. To attain 250 kg body weight (BW), the calves were allocated into three groups: high (H), low-high (L-H) and low (L) corresponding to concentrate levels receiving the concentrate at 1.50% of BW, 0.75%...
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An experiment was conducted using 17 male buffalo calves to assess the effects of plane of nutrition on dry matter intake (DMI), daily gain (DG), body size measurement, apparent digestibility and nitrogen (N) balance. To attain 250kg BW, the calves were allocated into three groups: H, L-H and L, receiving the concentrate at 1.50% of BW, 0.75% of BW...
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The objective of the present study was to determine the optimal culling strategy in relation to biological and economic efficiency (BE and EE, respectively) and annualized net revenue (AN) in the Japanese Black cow-calf production system with special reference to the beef quality of culled cows. The herd model focused on two ways of mating: one-mat...
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The effects of sex control and twinning techniques on determination of optimal culling parity of cows in beef cow-calf production systems were deterministically analyzed using a herd model simulation. The model simulated the annualized net revenue as an economic indicator during the whole life cycle of a cow. Biological factors (survivability, grow...