Open Paddock Research Articles

Shelter preference and behavior of dairy cows managed outdoors during calving in temperate winter conditions

This study aimed to assess the preference and use of an artificial shelter in dairy cows managed outdoors at calving during winter. We also evaluated whether this preference would be influenced by weather conditions (rain, air temperature, or wind) or the time of the day at calving. Two weeks before their expected calving date, 18 cows were paired based on body weight, body condition score, parity, and expected calving date. Each pair was assigned to an open paddock (42 m2/cow) with a bare soil surface, high mud content, and access to an artificial shelter until calving. The shelter consisted of a 6 × 3 m metal structure, with 3 sides covered with zinc sheets, a polycarbonate roof, and a thick layer of dry sawdust covering the ground surface. Shelter use and cow behavior inside it (lying and sleeping) were continuously recorded via video and analyzed using continuous observation. Observations were divided into 2 periods: the day before calving (24 to 48 h before calving) and the day of calving (24 h before calving until calving). Ninety-four percent (15/16) of the cows preferred to calve inside the artificial shelter, and this preference was not affected by the time of day or weather conditions. Regardless of the day of study (the day before calving or the day of calving), cows spent approximately 64% of their daily time inside the shelter, and once inside, they spent most of the time lying down. Our findings indicate dairy cows prefer using an artificial shelter as a calving and lying place, suggesting that opportunities for protection should be provided when they are managed outdoors in muddy paddock conditions.

Observations on the utilisation of a restored wildlife corridor by echo‐locating microbats in North Queensland's Wet Tropics

SummaryMicrobat studies are uncommon in the Wet Tropics of north‐east Queensland, despite the group comprising 20% of the bioregion's mammal fauna. The significance of fragmentation and habitat connectivity to the echolocating insectivore group is unknown. Over a 12‐month period in 2021–2022, microbat presence was recorded in a 25‐year‐old restored wildlife corridor 1.2 km in length. We deployed Anabat detectors in the restored corridor, in adjacent open paddocks and in mature rainforest at either end of the corridor. Species in reference forest and corridor vegetation were consistently ‘clutter‐adapted’ bats, with low aspect ratio wings; there was little overlap with high aspect ratio species of the open pasture. Low aspect ratio microbats appear to respond to the similarity in structure between restored and adjacent natural vegetation. Re‐establishing structural and functional connectivity may improve the local persistence of ‘clutter‐adapted’ microbats.

Effect of heat stress amelioration during dry period on biological responses, proinflammatory cytokines and milk production in subsequent lactation of Surti buffaloes

Present study was conducted on 12 dry Surti buffaloes to assess the effect of heat stress amelioration during dry period on their biological responses and milk production in subsequent lactation. Buffaloes were divided into control (n=6) and treatment (n=6) groups. Treatment buffaloes were housed only during their dry period in shed having wall-mounted fans, roof whitewashed with microfine lime powder and open paddock covered with 75% green net. At -8, -3, +1 and +3 weeks of calving, blood collection and recording of observations (physiological, skin thermography and BCS) were done. Milk composition and daily milk yield were recorded at every 2 weeks up to 11 weeks of lactation, respectively. Shed modification was successful in lowereing air temperature and THI indicating thermal comfort for treatment buffaloes as also revealed by lower temperatures of rectum, tympanic membrane, surface like forehead, eye, udder, coronet and lower respiration rate. Treatment group maintained significantly higher BCS, glucose, total protein, GSH, TAS, in vitro lymphocyte proliferation, neutrophil phagocytic activity and lower levels of urea, creatinine, NEFA, BHBA, SOD, MDA, cortisol, TNF-α, IL-1β, IL-6 and HSP70. These results are indicative of minimum negative energy balance, stress and higher immune response. Milk yield and fat were higher in treatment group. Providing thermal comfort to buffaloes in dry period helped in abating the negative effects of heat stress not only during dry period but also during subsequent lactation along with improved milk yield.

Sourcing and Management Practices by the Live-Goat Suppliers and Retailers in Lagos State, Nigeria

The sourcing and management practices of the live-goat suppliers and retailers in Lagos State, Nigeria were evaluated. Sources of the live-goat and the husbandry practices on them by suppliers and retailers were determined, using three-stage sampling procedures. Three livestock markets each from Lagos East, West and Central Senatorial Districts were purposively selected. Nine suppliers and 18 retailers were randomly selected in each market resulting to 81 and 162 respondents, respectively. Data on sourcing, handling, and holding period of live-goat were collected using two well-structured questionnaires for the suppliers and retailers of goats. Results showed that most suppliers (89.3%) purchased goats from open markets outside the state. The suppliers (52.0%) and retailers (80.0%) tethered goats. Most suppliers (77.3%) and retailers (90.0%) held goats for a maximum of three weeks, fed goats on dry grass sold in the open markets and some from open paddock. Routine administration of analgesic, dewormer, salt licks and water mainly sourced from boreholes and rivers were practices by both the suppliers and retailers. The age and level of education of the suppliers and retailers significantly influenced (p < 0.05) the management systems, handling, pest control, deworming, watering and additives used by the suppliers and retailers of goats. Most retailers (90.0%) belonged to markets regulated by different sectorial market associations while the local and state government officials in the markets performed no regulatory roles. Therefore, live-goat in Lagos State were sourced from other parts of Nigeria, handled, and managed by the suppliers and then retailers prior to their disposal in a manner directly influenced by the age and levels of education of the practitioners.

Provision of shelter during the prepartum period: Effects on behavior, blood analytes, and health status in dairy cows in winter

This study aimed to assess the effect of shelter provision during the prepartum period on lying, ruminating, and feeding behavior in outdoor-housed dairy cows exposed to winter weather conditions in a temperate climate. We also aimed to determine whether shelter provision during the prepartum period influenced blood analytes related to energy metabolism, body cleanliness, and health status. In this study, 2 cohorts of 12 multiparous Holstein prepartum cows were tested in winter. Twenty-five days before their expected calving date, the cows in each cohort were paired and randomly assigned to an open paddock without shelter or to one with access to an artificial shelter until calving. Shelter use, lying time, number of lying bouts, duration of lying bouts, rumination time, and feeding time were continuously recorded during the 3 wk before calving. Cows were assessed weekly for body cleanliness throughout the 3-wk prepartum period. A blood sample was taken from the coccygeal vein of each cow at wk -3, -2, -1, 1, 2, and 3 relative to calving date, and were assayed for nonesterified fatty acids (NEFA), β-hydroxybutyrate, and haptoglobin concentrations. Cases of clinical health disorders after calving were also recorded. The cows spent 60% of their daily time in the shelters, and for 75% of that time they were lying down. Cows with access to shelter during the prepartum period lay down around 3.2 h/d more than cows without shelter on wk -3 and -2 relative to calving. The cows with shelter access spent less time feeding during the morning (wk -3: 29.7 min; wk -2: 12.1 min; wk -1: 17.3 min) and afternoon (wk -3: 18.2 min; wk -2: 21.9 min) than cows without shelter access. As well, cows with shelter access showed a higher body cleanliness score (∼92 vs. ∼48%) and lower NEFA concentrations (wk -2: 0.27 vs. 0.44 mmol/L; wk -1: 0.46 vs. 0.64 mmol/L) in the precalving period, and lower haptoglobin concentrations in the first week postpartum (0.34 vs. 0.79 mg/mL) than cows without shelter access. We observed no treatment differences in daily rumination time, β-hydroxybutyrate concentrations, or postpartum health disorders. Despite the small number of dairy cows used in this study, these findings suggest that having access to a shelter during the prepartum period increases lying time, improves body cleanliness, and reduces adipose mobilization. Therefore, it is important to provide a protected area for the welfare of prepartum dairy cows exposed to winter climate conditions.

Effect of heat ameliorative measures on microclimate, physiological, blood biochemical parameters and milk production in lactating Surti buffaloes

The present investigation was carried out to evaluate the effect of heat ameliorative measures (fans, foggers, green agro shadenet) on physiological, haematological, biochemical and milk production parameters in Surti buffaloes. Lactating Surti buffaloes (36) were equally divided into two groups and kept in two sheds. Group I animals were housed in a shed without any modification while Group II animals housed in a shed fitted with fans and foggers inside the shed and roof top white washed with microfine lime and open paddock was covered with green shade net and foggers were fitted. There were significant differences in the THI values of both inside and outside of the sheds at majority of periods during the hot-dry season. The floor and roof temperature of control shed at almost all-time intervals was significantly higher than the floor temperature of treatment shed. Significant difference in rectal temperature was observed at 14 and 28 days while respiration rate was significantly lower in animals of treatment shed. In treatment group, total erythrocyte count and haematocrit was significantly low at day 21 and mean platelet volume was significantly high at day 42. Significantly high levels of cholesterol, chloride and sodium at day 21 and glucose, protein, triglyceride, GSH, TAS and sodium at day 42 were observed in treatment group. Weekly milk yield (kg) during hot-dry season was significantly higher for treatment group than control group at 3rd, 4th and 5th weeks of the experiment. Evening milk yield of treatment group was significantly higher than the control and the cumulative milk yield (for 42 days) was also significantly higher for treatment group than control group (180.08 vs.150.80 kg). It can be concluded that microclimate modifications help in reducing heat stress and has beneficial effect on physiological responses, blood biochemical parameters and total milk production in lactating Surti buffaloes during hot dry season.

Diurnal variation and oscillatory patterns in physiological responses and HSP70 profile in heat stressed yaks at high altitude

ABSTRACTThe present study was carried out at altitude of 3000 m above sea level (asl) to evaluate the impact of heat stress on yak adaptability. Sixteen healthy yaks of different age were randomly divided into two groups, calf (GI; n = 8) and adult (GII; n = 8). Experimental yaks were exposed to heat stress in the open paddock. THI ranged between 61.60 and 64.17 which were beyond the comfortable limit for yak. Post-exposure, rectal temperature increased (p < 0.01) by 2.97 °F and 2.42 °F in calf and adult yaks as compared to pre-exposure (100.08 ± 0.04 °F, 100.06 ± 0.05 °F). Respiration rate increased (p < 0.01) by 2.96 and 2.40 fold in calf and adult yaks with increased pulse rate on post-exposure to heat stress. The oscillatory patterns of physiological responses indicated that the level of heat stress increment was higher (p < 0.05) in calves than adult yaks. Plasma HSP70 increased (p < 0.01) by 7 fold in calf and 5 fold in adult yaks in comparison to pre-exposure level of 83.67 ± 1.11pg/ml and 80.65 ± 1.35 pg/ml. Thus, the yaks were experiencing heat stress at high altitude of 3000 m asl during the warmer months of the year and calves were more prone to heat stress as compared to adults.

Relationship of temperament with oestrous behaviour, resumption of ovarian cyclicity and milk yield in post-partum Murrah buffaloes.

This study was designed to investigate the relationship of temperament with oestrus, resumption of ovarian cyclicity and milk yield in post-partum buffaloes. For this study, 102 post-partum Murrah buffaloes were observed for temperament in open paddock and during milking. Based on the temperament score (1-5 score), they were classified into docile, slightly restless, restless, aggressive and nervous. Oestrous behaviour was monitored twice daily in all the buffaloes along with milk yield (weekly), body weight (BW) and body condition score (BCS) at day 0, 30, 60 and 90 post-partum. Based on the temperament score, the number of buffaloes classified as docile, slightly restless, restless and aggressive was 37 (36.27%), 28 (27.45%), 30 (29.41%) and 7 (6.86%), respectively, but none under nervous category. Number of buffaloes resuming cyclicity in various temperaments groups were as follows: docile (n=35; 94.59%), slightly restless (n=22; 78.57%), restless (n=20; 66.67%) and aggressive (n=7; 85.71%). Temperament was not correlated (p=.128; r=-.152) with oestrous behaviour. But, temperament was correlated (p<.0001; r=.384) with the resumption of cyclicity as docile and slightly restless buffaloes resumed cyclicity (p<.0016) earlier. Temperament of buffaloes was weakly correlated (p=.0017; r=-.306) with milk production with higher (p<.0358) total milk yield in docile (1022±23.75kg) and slightly restless buffaloes (948±35.86kg) as compared to other temperament groups. In summary, temperament of post-partum buffaloes was related with resumption of ovarian cyclicity and milk yield, but not oestrous behaviour.

Predation by Red Foxes (Vulpes vulpes) at an Outdoor Piggery

Simple SummaryPredation of piglets by red foxes is a significant risk for outdoor/free-range pork producers, but is often difficult to quantify. Using remote sensing cameras, we recorded substantial evidence of red foxes taking piglets from around farrowing huts, and found that piglets were most likely to be recorded as “missing” over their first week. These data suggest that fox predation contributed to the marked production differences between this outdoor farm and a similar-sized intensive farm under the same management, and warrant greater control of this introduced, invasive predator.Outdoor pig operations are an alternative to intensive systems of raising pigs; however for the majority of outdoor pork producers, issues of biosecurity and predation control require significant management and (or) capital investment. Identifying and quantifying predation risk in outdoor pork operations has rarely been done, but such data would be informative for these producers as part of their financial and logistical planning. We quantified potential impact of fox predation on piglets bred on an outdoor pork operation in south-western Australia. We used remote sensor cameras at select sites across the farm as well as above farrowing huts to record interactions between predators and pigs (sows and piglets). We also identified animal losses from breeding records, calculating weaning rate as a proportion of piglets born. Although only few piglets were recorded lost to fox predation (recorded by piggery staff as carcasses that are “chewed”), it is likely that foxes were contributing substantially to the 20% of piglets that were reported “missing”. Both sets of cameras recorded a high incidence of fox activity; foxes appeared on camera soon after staff left for the day, were observed tracking and taking live piglets (despite the presence of sows), and removed dead carcasses from in front of the cameras. Newly born and younger piglets appeared to be the most vulnerable, especially when they are born out in the paddock, but older piglets were also lost. A significant (p = 0.001) effect of individual sow identification on the weaning rate, but no effect of sow age (parity), suggests that individual sow behavior towards predators influences predation risk for litters. We tracked the movement of piglet carcasses by foxes, and confirmed that foxes make use of patches of native vegetation for cover, although there was no effect of paddock, distance to vegetation, or position on the farm on weaning rate. Trials with non-toxic baits reveal high levels of non-target bait interference. Other management options are recommended, including removing hay from the paddocks to reduce the risks of sows farrowing in open paddocks, and covering or predator-proof fencing the pig carcass pit. Results of this study will have increasing relevance for the expanding outdoor/free-range pork industry, contributing to best practice guidelines for predator control.

Population biology of Microlaena stipoides in a south-eastern Australian pasture

Microlaena (Microlaena stipoides var. stipoides (Labill.) R.Br.) is a C3 perennial grass that is native to areas of south-eastern Australia. In this region, perennial grasses are important for the grazing industries because of their extended growing season and persistence over several years. This series of experiments focused on the population biology of Microlaena by studying the phenology (when seed was set), seed rain (how much seed was produced and where it fell), seed germination, germinable seedbank, seed predation and seedling recruitment in a pasture. Experiments were conducted at Chiltern, in north-eastern Victoria, on an existing native grass pasture dominated by Microlaena. Seed yields were substantial (mean 800 seeds m–2), with seed rain occurring over December–May. Microlaena has two distinct periods of high seed rain, in early summer and in early autumn. Seed predation is high. Within a 24-h period during peak seed production, up to 30% of Microlaena seed was removed from a pasture, primarily by ants. Microlaena seedlings recruited throughout an open paddock; however, seedling density was low (5 seedlings m–2). Microlaena represented only low numbers in the seedbank (0.01–0.05% of total); hence, any seedlings of Microlaena that germinate from the seedbank would face immense competition from other species. Management strategies for Microlaena-dominant pastures need to focus on the maintenance of existing plants.

Fox baiting in agricultural landscapes: preliminary findings on the importance of bait-site selection

Context Little is known about the importance of bait-site selection during lethal fox-baiting programmes. Improved bait placement may increase the efficacy of baiting and help reduce fox impacts on wildlife and livestock. Aims To determine whether bait uptake by the red fox (Vulpes vulpes) differed among five landscape elements (roadsides, fence lines, open paddocks, creek lines and remnant vegetation) and at sites with high or low habitat (ground cover) complexity. Methods We measured bait uptake at 300 bait stations distributed evenly among the landscape elements in agricultural landscapes in northern Victoria, Australia. Bait uptake was also compared between sites with low and high habitat complexity in districts subject to no fox control and annual fox control. Key results Among landscape elements, bait uptake was significantly higher in roadside vegetation and along vegetated creek lines than it was along fence lines and in open paddocks (P &lt; 0.05 in each case). Within roadside vegetation, bait uptake was significantly (P = 0.001) lower at sites with a high habitat complexity than at sites with low complexity, particularly in areas subject to annual fox control. Conclusions Bait placement influences bait-uptake rates considerably and greater consideration should be placed on bait-site selection during fox-baiting programmes. Habitat complexity limited bait uptake, which may indicate a reduced capacity of foxes to find baits in complex habitats. Implications Our results should help improve bait-site selection in agricultural landscapes and may increase the efficacy of fox baiting to the benefit of native fauna and livestock.

Effect of roofing materials on micro-climate in loose house for animals during rainy season

Aim: To find out the influence of different types of roofing materials on micro-climate in animal loose housing system during rainy season. Materials and Methods: Different shade materials were used for covered area under each of three treatments. Thatch shading roof (T ), Agro-net shading roof (T ), Asbestos with canvas shading roof (T ). Long axis of the paddock was east-to-west 1 2 3 orientation. The covered area floor space was 1.5 ×1 m (excluding manger) for each animal and open paddock was 2 × 1 m. Height of shed at eaves was 2 meter. Daily temperature (maximum and minimum) and dry bulb and wet bulb temperature of macro and micro- environment under different treatments were recorded at 9:30 AM and 2:00 PM of Indian Standard Time (IST) by using maximum and minimum thermometer and dry and wet bulb thermometer. Both inside and outside surface temperatures of shade materials were measured by infrared digital thermometer (ebro, TFI 220). The statistical procedures followed were two way ANOVA and Paired 'T' test. Results: During the experimental period, maximum temperature was recorded under asbestos and lowest temperature was in agro-net and maximum protection from high temperature was given during peak hot hours in agro-net than asbestos. THI was more (P<0.05) under asbestos than agro-net and thatch.The outside surface temperature at 9.30 AM and 2:00 PM (IST) was significantly lower (P<0.05) in agro-net than thatch and asbestos. Conclusion: Thatch and agro-net were better in warding off the hot and humid environmental condition in comparison to asbestos.

Early detection of Trypanosoma evansi infection and monitoring of antibody levels by ELISA following treatment

In present communication, we report an outbreak of Trypanosoma evansi in equine herd n=30 (horse and mules) which, were reared in fly proof stables as well as in open paddock maintained under semi-intensive system of management, and its effective control using trypanocidal drug. The infection was monitored by antibody ELISA up to 180days post-treatment (PT). A total of 8 out of 14 equines (57.14%) which were maintained only in open paddocks were found positive with T. evansi infection parasitologically. The infected animals were treated with quinapyramine methyl sulphate and chloride combination administered at the prescribed dose rate on 3rd day of screening. The parasite could not be detected from any treated animals from day-3 PT up to 6month. Further, we also could not observe relapse of infection, neither in treated group nor in equine herd maintained at the farm. Sero-conversion was observed in all eight animals by 10th day of screening, indicating that immune response was due to recent infection as the animals became chronologically positive. The antibody titre reached at the peak by 10-14th day in all infected animals, and started declining by 17th day of screening, further reached to near cut off level by 180days. Since, antibodies persisted up to 6month PT and antibody detection assays are not able to differentiate between current and past infections in treated cases. The detection of circulating antigen assay and parasitological techniques in combination may be performed for effective diagnosis and management of T. evansi infection.

Applying home-range and landscape-use data to design effective feral-cat control programs

Context Effective feral-cat (Felis silvestris catus) management requires a sound understanding of the ways cats use their environment. Key characteristics of landscape use by cats vary widely among different regions and different conditions. Aims The present study aimed to describe the most important characteristics of landscape use by feral cats on a large, human-populated island, and to use this information to guide the development of feral-cat management programs. Methods We used GPS tracking collars to record the movements of 13 feral cats at two sites on Kangaroo Island, South Australia, for between 20 and 106 days. We described home-range extents by using local convex hulls, and derived management suggestions from examination of home-range and movement data. Key results Median feral-cat home range was 5.11 km2, and this did not differ between sexes or sites. Cats at a fragmented pastoral site tended to favour woody vegetation over open paddocks, but habitat preferences were less clear at a bushland site. Cats that preferentially used treelines at the pastoral site were almost twice as likely to be recorded close to a tree-line junction as expected. Conclusions Control programs for feral cats on Kangaroo Island should deploy control devices at a density no less than 1.7 devices km–2. Spatial coverage should be as large as practicable or repeated frequently. Infrequent programs covering small areas can be expected only to provide short-term reductions in cat abundance. Implications The information gained from the present study will contribute to the development of strategic sustained management plans for feral cats on Kangaroo Island. The principles from which we inferred management guidelines are applicable to other regions and species.

The extent and cost of mallee - crop competition in unharvested carbon sequestration and harvested mallee biomass agroforestry systems

Mallee-based agroforestry has potential to provide farmers with new income sources derived from biofuels, biofeedstocks, and carbon sequestration. Although mallees are planted on &gt;12 700 ha across the south-west of Western Australia, very little commercial harvesting of mallee has occurred to date. The development of biomass processing industries is constrained by lack of robust information regarding the productivity of integrated mallee and agricultural systems. This study addresses this constraint by quantifying the productivity and economics of agricultural crops and pastures growing in the competition zone adjacent to mallee belts at 15 sites across the Western Australian wheatbelt. The sites covered a range of climate and edaphic conditions, three mallee species (Eucalyptus polybractea R Baker, E. loxophleba ssp. lissophloia LAS Johnson and KD Hill, or E. kochii ssp. plenissima (CA Gardner) Brooker), various crop and pasture rotations, and various mallee harvest-management treatments. Mallee–crop competition was negatively correlated with rainfall and positively correlated with mallee age and size, and greater for crops than pasture. Consequently, extent and magnitude of competition were highly variable across sites and years. On average, mallee–crop competition extended 11.3 m from unharvested belts and reduced crop and pasture yields by 36% within 2–20 m of the mallee belts relative to open paddock yields. This is similar to what has been reported for taller tree species. Harvesting mallees reduced competition such that crop and pasture yield was reduced by 22 or 27% relative to open paddock yields for mallees harvested at 3- or 6+-year intervals, respectively. The economic cost of mallee–crop competition on agricultural enterprises was also highly variable between sites, and between years within individual sites. Averaged across all site-years, the opportunity cost of competition was equivalent to forgoing agricultural production for 14.4 m on each side of unharvested mallee belts, or 9–10 m on each side of harvested belts. Farmers with mallee agroforestry systems will need to manage the economic impacts of competition by reducing agricultural input costs in the competition zone, timing crop-grazing rotations with mallee harvests, ensuring that the width of alleys is at least 25 times the height of the mature trees, and possibly root-pruning mallees in unharvested or long harvest interval systems. This research has shown that mallee–crop competition presents a significant cost to farmers and must be considered when designing mallee agroforestry systems. The findings have relevance for the development of appropriate biomass and carbon sequestration pricing benchmarks for mallee plantings.

Litterfall and associated nutrient pools extend beyond the canopy of scattered eucalypt trees in temperate pastures

Scattered paddock trees are a keystone feature of temperate grazing landscapes of Australia. However, our understanding of their influence on their immediate environment, and specifically the spatial distribution and characteristics of litter, is still limited. Here, we quantified the spatial pattern of litter around 4 Eucalyptus species (Eucalyptus melliodora A. Cunn. Ex Schauer, E. viminalis Labill., E. blakelyi Maiden and E. michaeliana Blakely) in grazing landscapes on the Northern Tablelands of NSW, Australia. We examined the effect of species and soil parent material (basalt, granite and meta-sediments) on litter chemistry and chemical pools. Between 54–145 kg of litter was found around individual trees and litter density consistently declined with distance from the tree (330 g.m−2 in the inner canopy to 4 g.m−2 in the open paddock). However, an equivalent quantity of litter was found beneath and beyond the canopy indicating that a large quantity of the litter and nutrients fell beyond the edge of the canopy. Overall, leaf litter accounted for 23 to 34% of litterfall and had larger nutrient concentrations and pools than bark or stick litter. Most litter nutrients concentrations were independent of tree species or parent material but our results suggest that P, K and S were removed in foliage prior to abscission whilst Ca and Fe concentrations increased. The spatial patterns of litter distribution around scattered trees coincide with spatial patterns in soil properties that are frequently observed in these environments, and provide strong evidence of a significant link between these factors. Our results suggest that the removal of scattered trees from pastoral landscapes in this region of Australia will result in the loss of a significant litter input to the soil surface and will diminish this potentially important source of soil nutrients.

Effects of Merino flock size, paddock complexity and time of day on response to trained leaders

This study examined if Merino sheep trained to respond to a combined visual and auditory stimulus could influence the movement of naïve Merino sheep flocks when the stimulus was activated. Trained Merino ewes were mixed with naive ewes and wethers in three groups of different sizes. Group ratios were (trained:naïve) Small Mob (SM) 1:5 ratio ( n = 18), Medium Mob (MM) 1:10 ( n = 33) and Large Mob (LM) 1:15 ( n = 48). These groups were tested in 2 phases of increasing complexity. The first phase examined the responses of the different sized flocks (SM, MM and LM) to leader-initiated movement in 3 visually open paddocks (OP) during morning and afternoon grazing. The second phase examined the response of two flocks (SM and LM) at similar times but in 3 visually complex paddocks (CP). Animal groups were tested on 1 day per week in each paddock at pseudo random times. One hundred percent of the SM, 73.5% of the MM and 70% of the LM approached within 6 m of the stimulus in the OP tests. In the CP 100% of the SM and 56.5% of the LM approached the stimulus. The LM's proximity to the stimulus in some of the CP tests was more than 6 m, however, it was not significant compared to the other CP or OP tests. Sixty seven percent of the SM animals and 33% of the LM of naïve sheep were observed to initiate movement toward the stimulus after the 6 tests in phase one. At the end of the first phase of testing the proportion of naïve sheep observed to be eating the previously unknown grain (lupins) was SM 73%, MM 60% and LM 36%, suggesting that naïve sheep will learn to eat a novel grain by following trained animals. Sub-grouping of the flock in this study was not a hindrance to flock movement. This study demonstrated that sheep trained to respond to a stimulus do provide leadership when mixed with naive sheep flocks causing a flock to rapidly change position to congregate around an activated stimulus. These findings suggest that trained animals could be used to manipulate animal movement for farm management purposes.

The patterns of grazed pasture associated with scattered trees across an Australian temperate landscape: an investigation of pasture quantity and quality

Scattered paddock trees occur across agricultural landscapes in Australia. However, in the temperate regions of Australia their numbers are rapidly declining and they may be lost across much of the landscape in 200 years. Here we examined the spatial distribution of green (GDB), senescent (SDB) and total (TDB) dry pasture biomass, and nutrient status of the GDB fraction around scattered Eucalyptus trees on three parent materials (basalt, granite and meta-sediment) in native and sown pastures across a range of grazed temperate landscapes in northern New South Wales. We used a combination of destructive harvests and a handheld active optical canopy reflectance sensor (AOS) with an integrated GPS to examine pasture biomass around scattered trees. The harvested pasture biomass data indicated that under grazed conditions the presence of scattered trees did not introduce significant radial trends in TDB or GDB out to a distance of 3.5 canopy radii regardless of tree species or parent material. The red and near-infrared reflectance-based Normalised Difference Vegetation Index (NDVI), as measured by the AOS, did indicate a consistent azimuthal trend with larger GDB on the southern side of the tree and lower GDB on the northern side in the native pasture. However, this observation must be qualified as the regression coefficient for the relationship between NDVI and GDB was significant but weak (best r2 = 0.42), and SDB reduced its predictive capacity. We also found a higher percentage of GDB under the canopy than in the open paddock. We suggest that the combination of these results may indicate higher grazing pressure under trees than in the open paddock. Pasture nutrient concentration (P, K and S) was higher in both native and sown pastures beneath the tree canopy compared with the open paddock. This study indicates that, in this temperate environment, scattered trees do not adversely affect pasture production, and that they can improve some pasture nutrients.

Foraging behaviour of sheep at pasture with different types of paddock

This experiment was designed to study the foraging behaviour of ewes on a pasture with paddocks with three different types of vegetation, herbaceous (n = 3), woody (n = 2), and semi open (n = 1). Forty sheep were bred on a farm in the Karst region of Slovenia. Ten sheep were focally observed during day light (5 a.m.–9 p.m.). Ewes were observed for 2 days in each paddock with one rotation, so 12 days in total. Grazing time, circadian rhythm of grazing, drinking frequency, and frequency of salt consumption were the observed behaviours. On average, ewes grazed for 10.5 hours a day (mean ± SD = 626.2 ± 47.2 min), with a significant difference between individual variation (P &lt; 0.001). Sheep grazed the most in herbaceous paddocks (P &lt; 0.001), with lower yet similar levels observed in woody and semi open paddock. The frequency of drinking and salt consumption was low. Individual grazing sheep would drink slightly less than once per day, while consuming salt on average 1.25 times per day. Drinking frequency was the highest in the semi open paddock with some trees and bushes, whereas salt consumption was most frequently observed in the woody paddocks.

Shepherding in Colonial Australia

AbstractShepherds were a critical component of the early wool industry in colonial Australia and persisted even after fencing was adopted and rapidly spread in the later nineteenth century. Initially shepherds were convicts, but after transportation ceased in the late 1840s, emancipists and free men were employed. Their duty was the same as in England: look after the flock during the day, and pen them nightly in folds made of hurdles. Analysis of wages and flock sizes indicates that pastoralists achieved good productivity gains with larger flocks but inflation of wages reduced the gains to modest levels. The gold rushes and labour shortages of the 1850s played a minor role in increasing both wages and flock sizes. Living conditions in huts were primitive, and the diet monotonous. Shepherds were exposed to a range of diseases, especially in Queensland. Flock-masters employed non-whites, usually at lower wages, and women and children. Fences only replaced shepherds when pastoralists realised that the new technology of fences, combined with other changes, would give them higher profits. The sheep were left to fend for themselves in the open paddocks, a system used to this day.