The Effects of Heat Stress and Dietary Organic Acid and Pure Botanical Supplementation on Growth and Lactation in Dairy Cattle
The Effects of Heat Stress and Dietary Organic Acid and Pure Botanical Supplementation on Growth and Lactation in Dairy Cattle

Author: Ananda Barbara Portela Fontoura

Publisher:

Published: 2022

Total Pages: 0

ISBN-13:

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Heat stress (HS) compromises the gastrointestinal barrier and leads to inflammation in non-ruminants. However, it is unclear whether exposure to environmental conditions that cause HS enhances gastrointestinal permeability with compromised growth and milk production in dairy cattle. Developing nutritional strategies to manage HS in cattle are of importance to the dairy industry. Dietary supplementation of organic acid and pure botanicals (OA/PB) has been shown to improve growth performance by enhancing gastrointestinal health in swine and poultry species. Because the role of dietary OA/PB supplementation in ruminants had not received prior attention, our objectives were to 1) evaluate the effects of HS and dietary OA/PB supplementation on growth in dairy calves, and 2) evaluate the effects of HS and dietary OA/PB supplementation on gastrointestinal permeability and milk production in mid-lactating dairy cows. For study 1, sixty-two weaned heifer and bull calves (62 ± 2 d; 91 ± 10.9 kg) were randomly assigned to one of five groups (n = 11 to 14/group): thermoneutral conditions (TN-Con), HS conditions (HS-Con), TN conditions and pair-fed to HS-Con (TN-PF), HS with low-dose OA/PB (75 mg/kg of body weight [BW]; HS-Low), or HS with high-dose OA/PB (150 mg/kg of BW; HS-High). After a 7-d acclimation period, calves were exposed to TN or HS for a period of 19 d. Blood samples were collected and growth performance was evaluated. We observed that HS-Con calves had reduced growth compared to TN-Con and TN-PF. Regarding dietary OA/PB supplementation, HS-Low partially restored dry matter intake (DMI) without modifying growth performance. Thus, we conclude that dietary OA/PB supplementation does not improve growth performance in heat-stressed calves. For study 2, forty-six multiparous lactating dairy cows (208 ± 4.65 d in milk; 3.0 ± 0.42 lactation; and 39.2 ± 0.26 kg of milk yield) were randomly assigned to one of four groups (n = 10 to 12/group): TN-Con, HS-Con, TN-PF, or HS supplemented with OA/PB (75 mg/kg of BW; HS-OAPB). Cows acclimated in TN for 7-d, and then exposed to HS or remained in TN for 14-d. Blood and milk samples were collected. Changes in milk production and gastrointestinal permeability were evaluated. We observed that HS-Con cows had reduced DMI, energy-corrected milk yield, and milk protein and lactose yields compared to TN-Con, TN-PF and HS-OAPB cows. Milk- and plasma-urea nitrogen were reduced in HS-OAPB compared to HS-Con cows. Gastrointestinal permeability was greater in HS-Con, relative to TN-Con or TN-PF. We conclude that HS increased gastrointestinal permeability and that OA/PB feeding partially restores lactation performance by increasing DMI and improving intestinal barrier, and thereby enhancing milk yield and nitrogen efficiency.

Effects of Heat Stress and Dietary Zinc Source on Performance and Permeability of Mammary Epithelium of Lactating Dairy Cows
Effects of Heat Stress and Dietary Zinc Source on Performance and Permeability of Mammary Epithelium of Lactating Dairy Cows

Author: Xisha Weng

Publisher:

Published: 2017

Total Pages: 186

ISBN-13:

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Heat stress may negatively alter the barrier integrity of mammary epithelium, whereas organic source of dietary zinc has been shown to enhance epithelial integrity. The objective of the first study was to evaluate the effect of environmental heat stress and dietary zinc source (zinc-MET complex vs. zinc hydroxychloride) on lactating Holstein cows' performance and permeability of mammary epithelium. Heat stress impaired cow's performance and increased gene expression of tight junction proteins in mammary tissue. Replacing a portion of zinc hydroxychloride with zinc-MET complex had no impact on cow performance but improved mammary epithelial integrity. The objective of the second study was to examine the effect of repeated mammary tissue collections during lactation on cow performance and udder health of lactating dairy cows. Lactating cows recovered rapidly from mammary tissue collections and no long term impacts of repeated mammary biopsy procedures on DMI, milk yield and composition, or udder health were observed.

Heat Stress and Animal Productivity
Heat Stress and Animal Productivity

Author: Anjali Aggarwal

Publisher: Springer

Published: 2012-12-28

Total Pages: 188

ISBN-13: 9788132208785

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Dr. Anjali Aggarwal is working as a Senior Scientist at National Dairy Research Institute, Karnal (India). She holds a PhD degree in Animal Physiology and is involved in research and teaching at post-graduate level. Her area of research work is stress and environmental physiology. She has more than 50 publications, two technical bulletins, four manuals and many book chapters to her credit. She has successfully guided many post-graduate and PhD students. Her major research accomplishments are on microclimatic modification for alleviation of heat and cold stress, mist and fan cooling systems for cows and buffaloes, and use of wallowing tank in buffaloes. Her work involves the use of technology of supplementing micronutrients during dry period and early lactation to crossbred and indigenous cows for alleviating metabolic and oxidative stress and improved health and productivity. Studies are also done in her lab on partitioning of heat loss from skin and pulmonary system of cattle and buffaloes as a result of exercise or exposure to heat stress. Dr. R.C. Upadhyay is working as Head, Dairy Cattle Physiology Division at National Dairy Research Institute, Karnal (India). He graduated in Veterinary Sciences and obtained his PhD degree in Animal Physiology. His area of recent research is climate change, stress, and environmental physiology. His major research accomplishment is on climate change impact assessment of milk production and growth in livestock. His work also involves studying methane conversion and emission factors for Indian livestock and use of IPCC methodology of methane inventory of Indian livestock. Heat shock protein-70 expression studies in cattle and buffaloes are also done in his lab. Draught animal power evaluation, fatigue assessment, work-rest cycle and work limiting factors form the highlights of his work. Studies on partitioning of heat loss from skin and pulmonary system of cattle and buffaloes and electrocardiographic studies in cattle, buffalo, sheep and goat are also undertaken in his lab. He has more than 75 research papers, four books and several book chapters to his credit. Technologies developed and research done by him include methodology of methane measurement: open and closed circuit for cattle and buffaloes; inventory of methane emission from livestock using IPCC methodology; livestock stress index: thermal stress measurement based on physiological functions; and draught power evaluation system and large animal treadmill system. He received training in Radio-nuclides in medicine at Australian School of Nuclear Technology, Lucas heights, NSW, Australia in 1985 and Use of radioisotopes in cardiovascular investigations at CSIRO, Prospect, NSW, Australia, during 1985-86. He has guided several post-graduate and PhD students. He is recipient of Hari Om Ashram Award-1990 (ICAR) for outstanding research in animal sciences.

Effects of Heat Stress and Body Weight on the Performance, Health, Survival, and Physiology of Holstein Dairy Cattle
Effects of Heat Stress and Body Weight on the Performance, Health, Survival, and Physiology of Holstein Dairy Cattle

Author: Longfei Han

Publisher:

Published: 2022

Total Pages: 0

ISBN-13:

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Improving heat-stressed animal health and survival through management, nutrition, and genetics is critical to profitability and sustainability on a dairy farm. The objectives of this dissertation were to estimate genetic parameters of heat tolerance in dairy cattle for the health and survival traits; to investigate the long-term impact of heifer development; and to examine the potential role of ghrelin in thermoregulation during heat stress. Five experiments were conducted and summarized. The first experiment investigated the effect of heifer development (measured as body weight at first calving, BWFC) on milk production and survival. First lactation 305-d milk yield and 24-month milk yield were analyzed with a linear model. Survival analysis was performed to estimate the impact of BWFC on survival. Heifers in the top 60% of body weight at first calving had significantly higher first lactation 305-d milk yield than lighter heifers, but no relationship of BWFC and first lactation 305-d milk yield existed within the top 60%. Relationships between BWFC and 24-month milk yield were not significant. Heifers with higher BWFC lost significantly more body weight in early lactation. While BWFC was a significant predictor of first lactation 305-d milk yield, it accounted for 3% of variation, suggesting that BWFC is not a primary contributor to variation in milk yield. Compared to the lightest heifers, heaviest heifers were 49% more likely to be culled at any given time. These data indicated that, among heifers managed similarly, heavier heifers produced more milk in first lactation than lighter heifers, but lost more BW, faced a higher risk of being culled, and did not produce more milk long-term. The second experiment examined 1), the effect of climatic conditions at birth on organic calf stayability to 365 d of age (STAY) and respiratory disease (RESP) by 365 d of age, and 2), the genetic parameters of organic Holstein calf heat tolerance (HT) for STAY and RESP. HT was defined as the rate of change in STAY and RESP when a calf was born under heat stress. The final dataset included 77,090 calves from 16 USDA certified organic farms and included 35,520 Holsteins for genetic analyses. Phenotypic data were combined with climatic data obtained from local weather stations based on the zip code. Phenotypic analyses were performed with a model that included THI, breed, diurnal THI variation (daily maximum THI -- daily minimum THI; DTV), contemporary group, breed, and genetic effects. Estimated breeding values were calculated for Holstein sires with more than 10 daughters in the dataset. By 365 d of age, 80% of the calves stayed in the herd, and 7% of the calves recorded at least one RESP. Calf STAY decreased and RESP increased when calves were born in THI over 65. The additive genetic HT effect was significant for STAY but not RESP. The heritability for STAY and RESP were 0.100 and 0.025, respectively. In conclusion, calf STAY, RESP, and HT for STAY were heritable in organic herds and can be improved through genetic selection. The third experiment investigated the genetic and environmental effect of heat stress at calving on organic cow health and survival. Health trait were mastitis, reproductive disease, disease during the transition period (TRAN); and stayability to 30 DIM (1 = stayed in the herd, 0 = culled or died by 30 DIM; STAY30). The final dataset included 83,394 lactations from 40,712 cows of 6 different breeds of which Holstein (32,007 lactations, 15,938 cows) were most frequent and were used for genetic analysis. Weather condition at calving was defined as cool (average THI

Management Strategies to Reduce Effects of Thermal Stress on Lactating Dairy Cattle
Management Strategies to Reduce Effects of Thermal Stress on Lactating Dairy Cattle

Author: Rosemarie Burgos Zimbelman

Publisher:

Published: 2008

Total Pages: 358

ISBN-13:

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Two strategies to reduce impact of heat stress on high producing dairy cows were examined. The first was to recalculate the temperature-humidity index (THI) using high producing dairy cows under diurnal summer conditions. This re-evaluation confirmed that current THI values underestimate the severity of heat stress levels. Therefore, cooling of dairy cattle during warm summer months should begin at a THI of 68.A second objective involved three studies carried out to evaluate use of niacin in dairy cow rations to improve evaporative heat loss and resistance to heat stress. Niacin is known to cause intense vasodilation in human and lab species. We hypothesized that increasing vasodilation would improve evaporative heat loss in dairy cows. In the first niacin study, supplementation of lactating dairy cows with an encapsulated rumen by-pass form of niacin (NIASHURETM; Balchem Corporation, New Hampton, NY) and proved effective in alleviating some affects of heat stress during mild thermal stress. This was observed through increased evaporative heat loss, increased water intake to support the increased sweating rate, decreased rectal and core temperatures. Past research demonstrated that the possible mechanism for vasodilation affects seen by niacin were most likely due to prostaglandin D secretions. Niacin apparently may act through increased prostaglandin D and E production and secretion by Langerhans cells which then act upon vascular endothelial prostaglandin D receptors to increase vasodilation. Additionally, we and others have now shown that these prostaglandins induced elevated heat shock protein gene expression leading to improved cellular viability under heat stress conditions (42 ðC). No studies have evaluated impact of encapsulated niacin on milk yield and composition during periods of thermal stress under commercial dairy conditions. Therefore, the objective of the last study was to examine the effects of encapsulated niacin during heat stress on milk production and composition as well as core body temperatures under commercial conditions. We concluded that feeding encapsulated niacin did reduce body core temperature but did not increase daily milk yields; however, milk fat and protein percentages were increased thereby, increasing 4% fat- and energy-corrected milk yields significantly when animals were fed encapsulated niacin.

Nutrient Requirements of Laboratory Animals,
Nutrient Requirements of Laboratory Animals,

Author: National Research Council

Publisher: National Academies Press

Published: 1995-02-01

Total Pages: 188

ISBN-13: 0309051266

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In the years since the third edition of this indispensable reference was published, a great deal has been learned about the nutritional requirements of common laboratory species: rat, mouse, guinea pig, hamster, gerbil, and vole. The Fourth Revised Edition presents the current expert understanding of the lipid, carbohydrate, protein, mineral, vitamin, and other nutritional needs of these animals. The extensive use of tables provides easy access to a wealth of comprehensive data and resource information. The volume also provides an expanded background discussion of general dietary considerations. In addition to a more user-friendly organization, new features in this edition include: A significantly expanded section on dietary requirements for rats, reporting substantial new findings. A new section on nutrients that are not required but that may produce beneficial results. New information on growth and reproductive performance among the most commonly used strains of rats and mice and on several hamster species. An expanded discussion of diet formulation and preparationâ€"including sample diets of both purified and natural ingredients. New information on mineral deficiency and toxicity, including warning signs. This authoritative resource will be important to researchers, laboratory technicians, and manufacturers of laboratory animal feed.

Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc
Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc

Author: Institute of Medicine

Publisher: National Academies Press

Published: 2002-07-19

Total Pages: 798

ISBN-13: 0309072905

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This volume is the newest release in the authoritative series issued by the National Academy of Sciences on dietary reference intakes (DRIs). This series provides recommended intakes, such as Recommended Dietary Allowances (RDAs), for use in planning nutritionally adequate diets for individuals based on age and gender. In addition, a new reference intake, the Tolerable Upper Intake Level (UL), has also been established to assist an individual in knowing how much is "too much" of a nutrient. Based on the Institute of Medicine's review of the scientific literature regarding dietary micronutrients, recommendations have been formulated regarding vitamins A and K, iron, iodine, chromium, copper, manganese, molybdenum, zinc, and other potentially beneficial trace elements such as boron to determine the roles, if any, they play in health. The book also: Reviews selected components of food that may influence the bioavailability of these compounds. Develops estimates of dietary intake of these compounds that are compatible with good nutrition throughout the life span and that may decrease risk of chronic disease where data indicate they play a role. Determines Tolerable Upper Intake levels for each nutrient reviewed where adequate scientific data are available in specific population subgroups. Identifies research needed to improve knowledge of the role of these micronutrients in human health. This book will be important to professionals in nutrition research and education.