143 Heat Stress Mitigation Strategies for Boars and Impact of Most Effective on Sperm Parameters.

2018 ◽  
Vol 96 (suppl_2) ◽  
pp. 76-76
Author(s):  
E D Grusenmeyer ◽  
T J Safranski ◽  
M C Lucy ◽  
K Kerns ◽  
P Sutovsky ◽  
...  
Author(s):  
Matthew R Romoser ◽  
Katie L Bidne ◽  
Lance H Baumgard ◽  
Aileen F Keating ◽  
Jason W Ross

Abstract Heat stress (HS) mitigation strategies are critically needed to combat the substantial economic effects on animal agriculture. The manifestations of seasonal infertility include delayed puberty onset, reduced conception rates, decreased litter size, and increased wean to estrus interval. To assess the effects of HS during early gestation and evaluate a benefit of supplemental altrenogest (ALT) as a mitigation strategy, thirty crossbred post-pubertal gilts (157 ± 11 kg) were subjected to estrous synchronization via 14 d oral administration of ALT. Artificial insemination during estrus was performed and gilts were then placed into one of four treatment groups; heat stress (HS; 35 ± 1 οC for 12h/31.60 ± 1 οC for 12h) with (HSALT, n = 7) or without (HSCON, n = 7) 15 mg/d ALT supplementation or thermal neutral (TN; 20 ± 1 οC) conditions with (TNALT, n = 8) or without (TNCON, n = 8) 15 mg/d ALT supplementation until 12 d post-estrus (dpe). Administrating ALT occurred at 0600 h from 3-12 dpe and rectal temperatures (TR) and respiration rates (RR) were recorded. Blood was collected via jugular venipuncture on 0, 4, 8 and 12 dpe. Gilts were euthanized humanely at 12 dpe followed by collection of ovarian tissue, and uterine flushing for conceptus collection. In HS compared to TN gilts, RR and TR were increased (P < 0.01) but unaffected by ALT supplementation. Feed intake (FI) was reduced (P < 0.01) by HS but unaltered by ALT treatment. Corpora lutea (CL) weight was reduced (P < 0.01) in HSCON gilts when compared to TNCON and HSALT gilts despite progesterone (P4) concentrations in serum and luteal tissue not being affected by treatment (P ≥ 0.10). CL diameter was reduced (P ≤ 0.05) in HSALT gilts compared to other treatments. Interleukin-1β (IL1B) uterine flush concentration was not affected (P > 0.20) by environment or ALT supplementation, although moderate (P = 0.06) interaction between environment and ALT existed, as IL1B concentration in TNALT was increased (P = 0.03) compared to TNCON gilts. While environment did not affect conceptus development (P = 0.90), ALT supplementation advanced conceptus elongation (P < 0.01). Collectively, these data demonstrate that HS may affect luteal development prior to pregnancy establishment, and ALT increases conceptus elongation by12 dpe.


2022 ◽  
pp. 1256-1277
Author(s):  
Vishakha Shrimali ◽  
Nibedita Naha ◽  
Sukanta Mondal

Climate change is a global threat to livestock sector to so many species and ecosystem in different parts of the world. Climate change, heat stress, and nutritional stress are the major intriguing factors responsible for reduced fertility in farm animals in tropical countries. Heat and nutritional stresses affect the reproductive performance by decreasing the expression of estrous behavior, altering ovarian follicular development and hormonal profiles, compromising oocyte competence, and inhibiting embryonic development in livestock. Climate is changed by greenhouse gases that released into atmosphere through man-made activities. Livestock contribute 18% of the production of greenhouse gases itself and causes climate change including heat stress, which has direct and indirect impact on fertility of the animals as well as reduce milk production. Adaptation to climate change and lowering its negative effect by alteration of animal micro-environment using different essential technologies are the main mitigation strategies to recover heat stress damage in this respect.


2018 ◽  
Vol 78 ◽  
pp. 131-139 ◽  
Author(s):  
Aamir Nawab ◽  
Fahar Ibtisham ◽  
Guanghui Li ◽  
Barbara Kieser ◽  
Jiang Wu ◽  
...  

2021 ◽  
Author(s):  
Bruce Mutari ◽  
Julia Sibiya ◽  
Eileen Bongweh Nchanji ◽  
Kennedy Simango ◽  
Edmore Gasura

Abstract Background: Navy bean is an important legume crop in Zimbabwe. Its production is limited by multiple constraints including biotic, abiotic and socio-economic. However, in the major navy bean-production regions of Zimbabwe, there is no recent study documenting biotic stress management strategies, farmers’ perceived production, and marketing constraints, and cultivar trait preferences. Thus, this study aimed at identifying farmers’ production constraints, preferred traits and cultivars of navy bean, and strategies used to mitigate some of these constraints.Methods: A Participatory Rural Appraisal approach involving transect walks, focus group discussions (FGDs), and formal surveys with semi-structured questionnaires was conducted in four villages of the Lowveld region of Zimbabwe. In each of the four villages, two FGDs (one for men and one for women) were conducted. A total of 176 (75 males and 101 females) navy bean growing households were interviewed. Data from household interviews and FGDs was analysed using the Statistical Package for Social Scientists computer package.Results: The most important constraints to navy bean production were drought stress (Females – 86 %, Males – 73 %), heat stress (Females – 58 %, Males – 55 %), power outages (Females – 46 %, Males – 54 %), poor soil fertility (Females – 32 %; Males – 33 %) and susceptibility to pod shattering (Females – 32 %, Males – 43 %). Mitigation strategies included mulching (18 %), ridges (12 %), reduced acreage (11 %), and cultivating to retain more soil moisture (11 %) for drought stress, while irrigating at night (32 %), and adjusting planting dates (29 %) were used to manage heat stress. Farmer-preferred traits included tolerance to drought and heat, early maturing varieties and disease resistance. Marketing constraints included non-payment for produce in hard currency, lack of diversity in terms of off-takers, high inflation, low grain producer price, delayed payment and breach of contract by contractors. Conclusion: There will be increased adoption of improved navy bean cultivars if breeding programs address the aforementioned constraints and consider farmer-preferred traits when developing new cultivars. Breeders should work closely with extension officers to ensure that cultivars released are cultivated with appropriate agronomic packages for increased productivity and high adoption.


2019 ◽  
Vol 59 (2) ◽  
pp. 347 ◽  
Author(s):  
Lorena Román ◽  
Celmira Saravia ◽  
Laura Astigarraga ◽  
Oscar Bentancur ◽  
Alejandro La Manna

The negative effect of heat stress on dairy cows, with a temperature humidity index (THI) over 72, has been extensively studied. However, there are few studies on THI values under 72 that compare the effect of heat stress in different lactation stages. The objective of this study was to determine the heat stress effect on two lactation stages with a THI below the threshold 72. Thirty-nine multiparous, non-pregnant Holstein cows with more than 30 kg/cow.day of solid-corrected milk were used in a randomised complete block design to evaluate six treatments. The experimental design had a 3 by 2 factorial arrangement with three heat stress mitigation strategies: No shade (CON), access to shade only, and access to shade combined with sprinkling and ventilation, and two stages of lactation: early (S1) and late (S2), 12 ± 10.3 and 201 ± 45.8 days in milk respectively, for a duration of 81 consecutive days. All treatments, except CON had access to artificial shade from 0900 hours to 0500 hours next day. From 0500 hours to 0900 hours all cows were managed together in a grazing session. Additionally, sprinkling and ventilation cows had two 30-min sessions of ventilation and spray (0900 hours, 1530 hours). The average THI was 70.1 ± 4.46 (minimum THI: 60.4; maximum THI: 81.7) and the average hours above 72 were 7.8 ± 5.98. Animals in S1 presented higher solids-corrected milk reduction (P < 0.0001; 5.4 and 1.9 kg/cow.day), and protein yield (<0.0001; 0.13 and 0.54 kg/cow.day) than animals in S2 when shade was not allowed (CON). It was concluded that under these conditions, animal productivity is more negatively affected in early lactation animals. The use of shade with or without spray and ventilation mitigates heat stress effects on both stages of lactation.


2019 ◽  
Vol 97 (Supplement_2) ◽  
pp. 159-160
Author(s):  
Warren C Rusche ◽  
Ethan J Blom ◽  
Wesley W Gentry ◽  
Robbi H Pritchard ◽  
Allison VanDerWal ◽  
...  

Abstract Heat stress (HS) can be a significant source of risk for Midwestern cattle feeders. Feedlot managers (n = 46) from South Dakota, Minnesota, and Nebraska were surveyed regarding facilities, HS mitigation strategies, perceived success or failure, and strategies they would like to employ. Open yards (OY) were the most common system (62.5%), followed by total confinement (TC; 23.4%) and partial confinement (PC; 14.1%) with 15 respondents (32.6%) reporting multiple systems. Adjusting feed deliveries and introducing feed additives to mitigate HS were utilized by 32.6% and 34.8% of respondents, respectively. Environmental modifications were made to all OY (90% water application, 55% shades, and 25% bedding). Among respondents managing TC or PC facilities, in addition to the shade provided by buildings themselves 12.5% applied water during emergencies and 8.3% utilized fans. Cattle handling during heat events was scheduled to minimize HS by 100% of surveyed feedlots. During HS events, 67.4% adjusted shipping schedules and 32.6% provided additional water supply. Initiation of mitigation strategies were triggered by observed weather conditions (56.5%), indicators of cattle stress (39.1%), HS alerts (26.1%), and the calendar (6.5%). Shade-providing structures (TC, PC, or OY shades) were perceived as the most successful environmental modification (60.9%) followed by water application (50%), extra water supply (32.6%), and bedding (23.9%). Strategies perceived as less successful included water application (23.9%), feed additives (21.7%), and bedding (17.4%). Increased mud was specifically cited by 63.6% of respondents dissatisfied with water application. Respondents indicated providing more shade structures (63%) and confinement buildings (17.4%) for HS mitigation would be beneficial, but primary barriers were cost, time, and not a yet critical need (71.7, 21.7, and 10.9%, respectively). Midwest cattle feeders use many strategies specific to their needs to mitigate HS with those reducing solar load perceived as the most successful.


2018 ◽  
Vol 57 (2) ◽  
pp. 209-220 ◽  
Author(s):  
Shaoxiu Ma ◽  
Andy Pitman ◽  
Jiachuan Yang ◽  
Claire Carouge ◽  
Jason P. Evans ◽  
...  

AbstractGlobal warming, in combination with the urban heat island effect, is increasing the temperature in cities. These changes increase the risk of heat stress for millions of city dwellers. Given the large populations at risk, a variety of mitigation strategies have been proposed to cool cities—including strategies that aim to reduce the ambient air temperature. This paper uses common heat stress metrics to evaluate the performance of several urban heat island mitigation strategies. The authors found that cooling via reducing net radiation or increasing irrigated vegetation in parks or on green roofs did reduce ambient air temperature. However, a lower air temperature did not necessarily lead to less heat stress because both temperature and humidity are important factors in determining human thermal comfort. Specifically, cooling the surface via evaporation through the use of irrigation increased humidity—consequently, the net impact on human comfort of any cooling was negligible. This result suggests that urban cooling strategies must aim to reduce ambient air temperatures without increasing humidity, for example via the deployment of solar panels over roofs or via cool roofs utilizing high albedos, in order to combat human heat stress in the urban environment.


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