El Modelling potential distribution of the endemic ringtail (Bassariscus astutus saxicola) on an island in the Gulf of California

Objective: Analyze the topography of the island with a digital elevation model (DEM) at 30 m spatial resolution and generate the first distribution model for an endemic carnivore from the islands of the Gulf of California. Design/Methodology/Approach: This study employed the Maxent species distribution model to find the distribution of the ringtail in its habitat on Espíritu Santo Island. In 2015–2016, through four surveys, ringtails were trapped in eight glens on the west of the island. A total of 74 individuals were captured, with nine recaptures. Results: The variables with the greatest contributions to the models were elevation, contributing 71.6%; heat load index 15% and ruggedness 11.8%. The model predicts > 0.5 probabilities of presence of this carnivore in 3,018 hectares of the island. We obtained a high AUC value (0.928), which indicates that the model is accurate, and subsequently confirmed it with a value of pAUC = 1.917. Study Limitations/Implications: The habitat of the ringtail (Bassariscus astutus saxicola) was little known mainly because it is an endemic species. And there was not a published article that will show its distribution within the island. Conclusions: This model shows that topographic variables are useful to explain the potential distribution of the ringtail, mainly because the topography is related to sites that can offer thermal refuge, abundance of food, and escape routes from predators, among other features.

Using unmanned aerial vehicles to record behavioral and physiological indicators of heat stress in cattle on feedlot and pasture

Physiological and behavioral indicators of heat stress in cattle are time and labor-intensive to measure, and difficult to observe in extensive pasture settings. We proposed to record respiration rate and standing behavior using unmanned aerial vehicles. Videos were recorded above steers on feedlot in the morning (0830 – 1130) and afternoon (1400 – 1700) over ten days between July 25 – Aug 10, and cows on pasture over nine days between Aug 19 – 29. In the feedlot, video recordings on 925 individuals (264 black-coated, 413 red, and 248 white) were obtained, varying in breed which included Black Angus, Hereford, Charolais, Canadian Speckle Park, and Simmental. On pasture, video recordings on 267 individuals (116 Black Angus and 151 Hereford) were obtained. Observer software was used to analyze videos. Respiration rate in feedlot cattle was the highest in black cattle, followed by red cattle, then white cattle. Coat color did not affect respiration rate in cows on pasture; temperatures on pasture were lower than in feedlots and the effect of coat color may not manifest until a certain ambient or black globe temperature threshold. The probability that cattle would be standing increased with heat load index in feedlot and pasture settings.

Characteristics of Cowsheds in Vietnamese Smallholder Dairy Farms and Their Associations with Microclimate—A Preliminary Study

In smallholder dairy farms (SDFs), farmers often build cowsheds using local materials and based on self-accumulated experience without due consideration to reducing the risk of heat stress. This study aimed to characterise the heat stress abatement strategies and microclimate within SDF cowsheds from four typical dairy regions of Vietnam (south lowland, south highland, north lowland and north highland) and identify the housing parameters most associated with the microclimate. The study was conducted on 32 SDFs (eight SDFs per region) in autumn 2017. Twelve housing management variables, illustrating cowshed design and heat stress abatement methods of each SDF, were collected. Six microclimate parameters, collected within the cowshed, were temperature (AT), humidity, air speed (AS), heat load index (HLI), Temperature-humidity index (THI) and accumulated heat load units (AHLU) during a day (06:00 h to 18:00 h). Factor analysis and cluster analysis was applied to group cowsheds of SDFs into clusters where SDFs in the cluster had the same cowshed characteristics. Multivariable linear models were applied to define the parameters most likely to inform future research into heat stress mitigation on SDF. Averaged from 08:00 h to 18:00 h, microclimate inside the cowsheds was considered hot (HLI > 79) in the highland and very hot (HLI > 86) in the lowland regions. Cows in the lowland regions accumulated high heat load (AHLU > 50) by 18:00 h. Cowsheds of SDFs varied widely and grouped into seven cowshed types, but no type was more effective than others in reducing heat stress conditions within cowsheds. Using roof soakers together with fans decreased AT and HLI by 1.3 °C and 3.2 units, respectively, at 14:00 h compared to 11:00 h. Each 100 m increase in altitude was associated with decreases of 0.4 °C in AT, 1.3 units in HLI and 0.8 units in THI (p < 0.001). Each meter increase in the eave height of the cowshed roof was associated with decreases of 0.87 °C in AT, 3.31 units in HLI and 1.42 units in THI, and an increase of 0.14 m/s in AS (p < 0.05). The cowshed parameters that should be prioritised for future research into the amelioration of heat stress in SDF cows include using the roof soakers together with fans, increasing altitude, eave roof height and floor area per cow.

Regeneration dynamics of Great Basin bristlecone pine in southern Nevada

Great Basin bristlecone pine (Pinus longaeva D.K. Bailey) is an important and long-lived tree species found at high elevations in the interior southwest of the United States, but little is known about its regeneration requirements and response to disturbance. We conducted extensive surveys of seedling regeneration and environmental attributes of regeneration sites in undisturbed forest dominated by this species in the Spring Mountains of southern Nevada. Additional surveys tallied new seedling densities and site attributes 4 years after a wildfire in the same area. Seedlings, saplings, and juvenile trees were less abundant than adult trees in the unburned forest, and soils had lower bulk density and greater depth, moisture, and soil organic matter under adult trees than in open areas. Seedling distributions in both unburned and burned forest showed a negative relationship to a heat load index governed by aspect. The density of new seedlings after the fire was negatively related to distance from unburned forest edges. Seedlings were found in clusters and were associated with adult trees (live or dead) in both unburned and burned stands. Seedling emergence from animal-dispersed caches was more frequent in burned habitats than in unburned habitats. These natural regeneration dynamics provide potential guidance for restoration efforts in this ecosystem.

GIS-Based and Statistical Approaches in Archaeological Predictive Modelling (NE Romania)

Archaeological predictive modelling (APM) is an important method for archaeological research and cultural heritage management. This study tests the viability of a new statistical method for APM. Frequency ratio (FR) is widely used in the field of geosciences but has not been applied in APM. This study tests FR in a catchment from the north-eastern part of Romania to predict the possible location(s) of Eneolithic sites. In order to do that, three factors were used: soils, heat load index and slope position classification. Eighty percent of the sites were used to build the model, while the remaining 20% were used to externally test the model’s performance. The final APM was made with the help of GIS software and classified into four susceptibility classes: very high, high, medium and low. The success rate curve and the prediction rate curve reported values of the area under curve (AUC) of 0.72, and 0.75 respectively. The Kvamme’s Gain value for the model has a value of 0.56. Therefore, the final APM is reliable, so FR is a viable technique for APM. The final map can be successfully used in archaeological research, cultural heritage management and protection, preventive archaeology and sustainable development.

10 Finishing beef cattle under cover reduces heat load and improves efficiency during the summer

Heat-stress in finishing cattle presents a significant risk to efficiency and economic viability. The project objective was to quantify the effects of long-term heat stress when finishing cattle during the summer in the southeastern United States. Forty-five Angus crossbred steers (446±23 kg) were blocked by weight and randomly assigned to environmental finishing treatments including: covered with fan (CWF), covered without fan (CNF), or outside without shade (OUT). For 92 d steers were individually fed a typical feedlot ration. Environmental data were continuously recorded including: black globe temperature (BG), heat load index (HLI), and accumulated heat load units (AHLU). Feed intake was recorded daily, and steers were weighed every 20–25 days. When the first treatment averaged 613-kg all steers were slaughtered, and carcass data were collected. Data were analyzed as a Mixed Model (JMP V13; SAS Inst.) and means were separated (Least Squares Means). Average maximal BG was lower for covered finishing than OUT (P < 0.01) however for HLI CWFCNF>OUT, while G:F was similar (P = 0.22) between CWF and CNF, which were greater (P < 0.01) than OUT. Hot carcass weights were heavier for CWF than OUT (P < 0.01) and CNF was similar to both (P ≥ 0.11). There was no difference for USDA Yield Grade (2.6; P = 0.44), or marbling score (Modest20; P = 0.76). Steers finished under cover were more efficient than steers finished in open dry-lots. The addition of cooling fans further improved steer gains over those that were covered without fans.

199 Effects of high heat load conditions on Dorper, Katahdin, and St. Croix sheep from different regions of the USA

Forty-six Dorper, 46 Katahdin, and 43 St. Croix female sheep (initial BW of 58, 59, and 46 kg, respectively, SEM = 1.75; 3.3 ± 0.18 yr of age, 2.6 - 3.7) from 45 commercial farms in four regions of the USA (Midwest, Northwest, Southeast, and central Texas) were used to evaluate responses to high heat load index (HLI) conditions in a central facility. The four trials entailed sequential 2-wk periods with target HLI during day/nighttime of 70/70 (thermoneutral zone conditions during the day and night), 85/70, 90/77, and 95/81, with weekly measures at 0700 (before increased daytime HLI), 1300, and 1700 h (preceding lower nighttime HLI). Rectal temperature (ºC) in period 3 (38.64, 38.66, and 38.48 at 0700 h, 39.08, 39.23, and 38.84 at 1300 h, and 39.20, 39.15, and 38.99 at 1700 h) and period 4 (38.71, 38.90, and 38.51 at 0700 h, 39.18, 39.12, and 38.83 at 1300 h, and 39.45, 39.34, and 39.07 at 1700 h for Dorper, Katahdin, and St. Croix, respectively) (SEM = 0.054, 0.037, and 0.038 at 0700, 1300, and 1700 h, respectively) ranked St. Croix < Katahdin < Dorper. Nonetheless, there were corresponding differences in respiration rate (breaths/min) in period 3 (63.1, 56.8, and 49.6 at 0700 h, 133.8, 125.8, and 115.7 at 1300 h, and 125.5, 114.7, and 106.8 at 1700 h) and period 4 (81.6, 72.2, and 54.5 at 0700 h, 149.2, 143.6, and 137.3 at 1300 h, and 147.0, 141.4, and 134.2 at 1700 h for Dorper, Katahdin, and St. Croix, respectively) (SEM = 3.12, 4.11, and 3.62 at 0700, 1300, and 1700 h, respectively). In conclusion, based on rectal temperature and respiration rate the overall impact of region was minimal and resilience to high HLI was greatest for St. Croix and lowest for Dorper sheep

124 Finishing beef cattle under cover reduces heat load and improves efficiency during the summer

Heat-stress in finishing cattle presents a significant risk to efficiency and economic viability. The project objective was to quantify the effects of long-term heat-stress when finishing cattle during the summer in the southeastern United States. Forty-five Angus crossbred steers (446±23 kg) were blocked by weight and randomly assigned to environmental finishing treatments including: covered with fan (CWF), covered without fan (CNF), or outside without shade (OUT). For 92 d steers were individually fed a typical feedlot ration. Environmental data were continuously recorded including: black globe temperature (BG), heat load index (HLI), and accumulated heat load units (AHLU). Feed intake was recorded daily, and steers were weighed every 20–25 days. When the first treatment averaged 613-kg all steers were slaughtered, and carcass data were collected. Data were analyzed as a Mixed Model (JMP V13; SAS Inst.) and means were separated (Least Squares Means). Average maximal BG was lower for covered finishing than OUT (P < 0.01); however, for HLI CWFCNF>OUT, while G:F was similar (P = 0.22) between CWF and CNF which were greater (P < 0.01) than OUT. Hot carcass weights were heavier for CWF than OUT (P < 0.01) and CNF was similar to both (P ≥ 0.11). There was no difference for USDA Yield Grade (2.6; P = 0.44), or marbling score (Modest20; P = 0.76). Steers finished under cover were more efficient than steers finished in open dry-lots. The addition of cooling fans further improved steer gains over those that were covered without fans.