Autumn Pasture Research Articles

Pasture phytocomplexes of Pridonye: Ecological situation

The purpose of the work is to establish the ecological situation in the pasture phytocomplexes of the Don basin. The objects of research were plant communities on floodplain sod-meadow granular soils and on the sands of the Ilovlinsky massif of the Volgograd region. The occurrence of species on the Drude scale, the vital state of plants, the projective cover of vegetation, and the feed mass consumed were determined. It is established that the main mass of vegetation is oppressed or is in a satisfactory condition. The dominant phytocomplexes are representatives of the Asteraceae families that are resistant to anthropogenic loads and lodging, with a wide ecological amplitude (30% on floodplain sod-meadow granular soils, 38% on sands) and Poaceae (13% on floodplain sod-meadow granular soils, 29% on sands). On floodplain sod-meadow granular soils with a projective vegetation cover of 45%, the feed mass of autumn pastures was 51.2 g/m2, on sands with an average projective vegetation cover of 21%, the feed mass was 24.4 g/m2.

Persistence of perennial ryegrass, tall fescue and cocksfoot following annual sowings: influence of grass species, ryegrass cultivar and pasture age on yield, composition and density

Persistence is an important component of perennial pasture-grass productivity. Defining traits that affect persistence is essential for improving pasture longevity through plant breeding and for identifying persistence traits that should be included in cultivar ranking indices. Compared with conventional longitudinal studies, where a single sowing is monitored over time, repeated annual sowings allow the effects on persistence of sowing year and the ensuing interactions between environment and age of pasture to be identified. An experiment was commenced in 2015 under sheep grazing in Canterbury and in 2016 under cattle grazing in Waikato, where eight cultivars of perennial ryegrass representing different ploidy, flowering date, and cultivar age (release date), and one cultivar each of tall fescue and cocksfoot were sown in four randomised complete blocks in autumn each year. This paper reports interim data on spring and autumn pasture yield, composition, and density of 3-year-old, 2-year-old and 1-year-old pastures exposed to the same environmental conditions within the same, single year. There were significant effects on yield, botanical composition, basal cover and tiller density due to cultivar, pasture age, and their interaction. When the confounding effect of year-to-year variation was removed by comparing each age cohort in the same year, the underlying differences among grass species and cultivars, and ages of pasture, is starting to reveal the nature of this influence on pasture persistence.

Restricting dairy cow access time to pasture in autumn: The effects on milk production, grazing behaviour and DM intake of late lactation dairy cows

Extending the grazing season in pasture based systems of dairy production can increase farm profitability; poor weather and soil conditions can reduce the number of grazing days. The study objectives were to (i) examine the effect of restricted access to pasture in the autumn on the milk production, grazing behaviour and DM intake (DMI) of late lactation spring-calving dairy cows and (ii) establish the effect of alternating restricted and continuous access to pasture on dairy cow production, DMI and grazing behaviour. Cows were randomly assigned to one of four grazing treatments: (i) 22 h (full-time) access to pasture (22H; control); (ii) Two 5-h periods of access to pasture (2×5H); (iii) Two 3-h periods of access to pasture (2×3H); and (iv) alternating between full-time and 3-h access to pasture with no more than three continuous days on any one regime, e.g. Monday – full-time access, Tuesday − 2x3H access, Wednesday − 2x3H access; Thursday – full-time access, etc. (2×3HV). Restricted access to pasture was offered after a.m. and p.m. milking. Swards of similar quality and pregrazing herbage mass were offered. Treatment had no effect on milk yield (13.2 kg/day), milk fat (48.2 g/kg), protein (39.0 g/kg) or lactose content (42.6 g/kg) and milk solid yield (1.15 kg/day). Similarly, there was no effect of treatment on final BW (483 kg) or final BCS (2.66). There was no significant difference in DMI (15.1 kg DM/cow/day) between treatments. There was an effect on daily grazing time, 22H cows (565 min/cow/day) grazed for longest time, however, when the 2x3HV treatment had full-time access to pasture, they had a similar grazing time (543 min/cow/day) to the 22H cows and were similar to the 2x3H treatment on days with restricted access to pasture (357 min/cow/day). The 22H and 2x5H animals had similar grass DMI/min (29.2 g/min), the 2x3HV were higher (33.9 g/min) but were similar to the comparable treatment when offered 2x3H access time (41.6 g/min) and when offered 22H access time (27.7 g/min). The results from this study show how when offered a grass only diet of autumn pasture grazing behaviour can be modified by restricting pasture access time without reducing dairy cow production in late lactation at low production levels. There was also no effect of alternating access time between 22H and 2x3H on milk production and DMI in the 2x3HV treatment. Restricted access time to pasture in autumn may be a strategy which farmers can use to extend the grazing season.

Effect of slope aspect on vegetation characteristics in mountain rangelands of Tajikistan: considerations for future ecological management and restoration

Tajikistan’s rangelands are mostly mountainous and consist of summer and winter pastures. Vegetation structure and composition in these diverse landscapes are generally influenced by environmental factors. The objective of this study was to assess the effects of aspect on vegetation characteristics of two mountainous pastures (summer and winter) over two seasons (autumn and spring) in Tajikistan. A three-way ANOVA was conducted using GLM procedures to test the main effects and interactions of these factors on vegetation attributes. The biomass production (kg DM ha−1) was significantly greater on the north-facing aspects for both summer and winter pastures in spring (483.4, 326.1) and autumn (57.2, 143.9), compared with south-facing aspects (57.2, 143.9 in spring and 18.5, 48.2 in autumn, respectively). Plant cover and plant density were also greater on north than south-facing slopes for summer and winter pastures in spring and autumn. Aspect significantly affected species diversity, botanic composition, and plant life forms of both pastures mainly for grasses and geophytes. There were greater vegetation responses on north than south-facing slopes, implying that aspect is important when designing mountain rangeland restoration. Given this complexity, land managers should thoroughly assess the conditions of the target site before defining restoration objectives and interventions.

Assessment of Spatio-Temporal Variation and Driving Mechanism of Ecological Environment Quality in the Arid Regions of Central Asia, Xinjiang.

Grassland ecosystems are increasingly threatened by pressures from climate change and intensified human activity, especially in the arid region of Central Asia. A comprehensive understanding of the ecological environment changes is crucial for humans to implement environmental protection measures to adapt to climate change and alleviate the contradiction between humans and land. In this study, fractional vegetation coverage (FVC), leaf area index (LAI), gross primary productivity of vegetation (GPP), land surface temperature (LST), and wetness (WET) were retrieved from Moderate-Resolution Imaging Spectroradiometer (MODIS) satellite remote sensing products in 2008 and 2018. Principal component analysis (PCA) was used to establish the MODIS data-based ecological index (MODEI) in the study area, and the spatial differentiation characteristics and driving mechanism of ecological quality in the last ten years were explored. The results showed that: (1) FVC, GPP, LAI, and WET had positive effects on the ecological environment, while LST had a negative impact on the ecological environment. FVC and GPP were more significant than other indicators. (2) The MODEI showed a spatial pattern of “excellent in the north and poor in the south” and changed from north to south in the study area. (3) From 2008 to 2018, the average MODEI of Fuyun County increased from 0.292 to 0.303, indicating that the ecological quality in Fuyun County became better overall. The improved areas were mainly located in the summer pastures at higher elevations. In comparison, the deteriorated areas were concentrated in the spring and autumn pastures and winter pastures at lower elevations. The areas where the ecological environment had obviously improved and degraded were distributed along the banks of the Irtysh River and the Ulungur River. (4) With the increase in precipitation and the decrease in grazing pressure, the MODEI of summer pasture was improved. The deterioration of ecological environment quality in spring and autumn pastures and winter pastures was related to the excessive grazing pressure. The more significant changes in the MODEI on both sides of the river were associated with implementing the herdsmen settlement project. On the one hand, the implementation of newly settled villages increased the area of construction land on both sides of the river, which led to the deterioration of ecological quality; on the other hand, due to the increase in cropland land and the planting of artificial grasses along the river, the ecological quality was improved. The study offers significant information for managers to make more targeted ecological restoration efforts in ecologically fragile areas.

On-farm examination of sainfoin supplementation effects in dairy cows in a roughage-based feeding system: Indicators of protein utilisation

A case study was conducted with the objective to determine the effects of the tanniferous legume sainfoin (Onobrychis viciifolia) on protein utilisation of dairy cows, which were exposed to excessive dietary crude protein during autumn pasture grazing in a zero-concentrate feeding system. The study was conducted under practical conditions, deliberately accepting a certain lack of controllable variables. In order to assess a system applicable in practice, relatively small amounts of sainfoin were offered, and graded supply levels were compared by varying the duration of offer instead of dietary concentration. Within one dairy herd of 60 Swiss Fleckvieh cows, 30 individuals were chosen and randomly allocated to three groups balanced for milk yield, milk urea concentration, days in milk and parity. Over a period of 5 weeks, 2 kg per cow and day of sainfoin pellets were provided either intermittently, for 2 × 5 days (SST) in weeks 3 and 5 of the experiment or continuously over 35 days (SLT). A control group (CON) received 2 kg per cow and day of ryegrass pellets during the 5 weeks. The entire herd grazed on a protein-rich natural sward and was kept overnight in an open-space barn receiving fresh grass and hay ad libitum. Experimental pellets were offered individually twice per day in buckets. Feed, milk, faeces and urine samples were collected in weeks 0 (baseline), 3 and 5. Milk was analysed for fat, protein and urea, urine for purine derivatives, creatinine and nitrogen, and faeces for protein, fibre and particle fractions. During three sampling weeks, chewing activity was recorded by sensor halters. Treatment SST increased rumination time in the first half of the day, which was the only treatment effect on intake and rumination behaviour. Milk fat and protein yields were greater in SST compared to CON, but no treatment effect on concentration and yield of milk urea was found. The proportion of particle fractions in faeces was smaller in both sainfoin treatments compared to CON. In urine, the ratio of purine derivatives to creatinine tended to be higher in SST than in CON, and total urinary nitrogen excretion was lower, indicating a slightly better protein efficiency in SST. In summary, the study revealed small positive effects on protein metabolism and yield when sainfoin was applied short-term over two short periods, whereas long-term application had no effect.

Effect of 3 autumn pasture management strategies applied to 2 farm system intensities on the productivity of spring-calving, pasture-based dairy systems

The objective of this study was to investigate the effect of altering autumn pasture availability and farm system intensity on the productivity of spring-calving dairy cows during autumn. A total of 144 Holstein-Friesian and Holstein-Friesian × Jersey crossbred dairy cows were randomly assigned to 2 whole farm system (FS) intensities and 3 autumn pasture availability (PA; measured above 3.5 cm) treatments in a 2 × 3 factorial arrangement. The 2 farm systems consisted of a medium intensity (MI: 2.75 cows/ha, target postgrazing sward height of 4.0-4.5 cm) and high intensity system (HI: 3.25 cows/ha, target postgrazing sward height of 3.5-4.0 cm, + 1.8 kg of concentrate dry matter [(DM)/cow per day]. Within each farm system treatment, cows were further subdivided into 3 different PA management strategies: high PA (HPA), medium PA (MPA), and low PA (LPA). The experimental period lasted for 11 wk from September 1 to housing of all animals on November 20 (±2 d) over 3 yr (2017-2019, inclusive). To establish the different average pasture covers for each PA treatment during autumn and in particular at the end of the grazing season, grazing rotation length was extended by +13 and +7 d for HPA and MPA, respectively, beyond that required by LPA (37 d). There were no significant FS × PA interactions for any of the pasture, dry matter intake, or milk production and composition variables analyzed. There were also no differences in pregrazing sward characteristics or sward nutritive value between FS with the exception of daily herbage allowance, which was reduced for HI system (12.2 vs. 14.2 kg of DM/cow). Milk and milk solid yield were greater for HI groups (15.9 and 1.55 kg/cow per day, respectively) compared with MI (15.4 and 1.50 kg/cow per day, respectively). Mean paddock pregrazing herbage mass was significantly higher with increased PA ranging from a mean of 1,297 kg of DM/ha for LPA to 1,718 and 2,111 kg of DM/ha of available pasture for MPA and HPA, respectively. Despite large differences in pregrazing herbage mass, there was no difference in cumulative pasture production and only modest differences in grazing efficiency and sward nutritive value between PA treatments. On average, closing pasture covers were 420, 650, and 870 kg of DM/ha for LPA, MPA, and HPA, respectively, on December 1. In addition to maintaining similar grazing season lengths and achieving big differences in availability of pasture on farm into late autumn, PA treatment had no significant effect on dry matter intake, milk production, and body condition score during the study period. The results of this study indicate that greater cow performance and pasture utilization can be achieved through a greater daily concentrate allocation along with an increased stocking rate. Moreover, the potential to adapt grazing management practices to increase the average autumn pasture cover in intensive grazing systems is highlighted. In addition, a high dependence on high-quality grazed pasture during late autumn can be ensured without compromising grazing season length while also allowing additional pasture to be available for the subsequent spring.

Effects of grazing exclusion on spring and autumn pastures in arid regions of China: Insights from field surveys and landsat images

Overgrazing has caused serious grassland degradation, and grazing exclusion (GE) has been considered an effective and economic approach for restoring vegetation and soils in degraded grassland. In this study, we evaluated the ecosystem restoration of two types of degraded spring and autumn pasture in arid regions of northwest China, based on field surveys (community structure characteristics, soil C and N) and Landsat images (greenness and wetness). In temperate typical steppe (TS), our findings indicated that GE significantly increased plant height, coverage, biomass, soil C and N, as well as greenness and wetness values from Landsat images, however GE decreased plant density and species diversity. Restoration on greenness and wetness peaked in the fourth and fifth years, respectively, following GE. The restoration of greenness and wetness showed bimodal curves during growing season. In temperate desert (TD), results revealed that community structure characteristics, greenness, and wetness improved after GE, and the restoration of greenness and wetness increased with duration of GE. Soil C and N however, did not recover significantly after six years of GE. The restoration of greenness and wetness remained stable during growing-season months. Our findings suggest that longer GE might be considered in the restoration of TD, whereas short-term (not more than 4–5 years) GE, reduction in the livestock load or mowing regularly may be more appropriate for TS. Decision to adopt measures of GE and the duration of GE should be reasonably determined according to the specific grassland type. This research can provide guidance for the restoration of degraded grassland ecosystems in arid and semi-arid regions all over the world.

高寒典型草原主要物种的株高和盖度预测种群和群落地上生物量

为快速、准确、无破坏地测定草原地上生物量，在祁连山高寒典型草原植物生长旺季，观测了冬季和春秋季放牧地60个样方内各物种的株高、盖度等生长指标。以冬季牧地紫花针茅（Stipa purpurea）、醉马草（Achnatherum inebrians）、赖草（Leymus secalinus）、扁穗冰草（Agropyron cristatum）、二裂委陵菜（Potentilla bifurca）、银灰旋花（Convolvulus ammannii）6个主要物种的株高、盖度、株高和盖度的乘积为自变量，分别预测同物种、其他物种和群落地上生物量。用春秋季牧场的数据验证模型的精确性和稳定性。结果表明：主要物种的生长指标可预测其自身、其他物种和群落地上生物量。对自身种群，株高和盖度乘积的复合因子预测效果最好；4种禾草对其他物种、二裂委陵菜对菊科植物种群，株高、盖度单因子预测效果优于复合因子；6个主要物种单独或2-6个种结合均可预测群落地上生物量，但是以6个物种株高和盖度的乘积同时预测时决定系数最大，可解释群落地上生物量89.5%的变异，为高寒典型草原群落地上生物量最优预测模型。;In order to fastly, accurately and non-destructively to predict the biomass on alpine typical steppe in Qilian Mountains, growth indexes of plants species such as plant height, coverage were observed during the growing season under two different pastures, which are Winter grazing land and spring and autumn grazing land. In total 60 quadrats were measured. Taking the Plant height, coverage, the product of plant height and coverage of 6 major species in winter pasture,such as Stipa purpurea, Achnatherum inebrians, Leymus secalinus, Agropyron cristatum, Potentilla bifurca and Convolvulus ammannii as independent variable, and the main population, other populations and aboveground biomass of the community in the same quadrat were used to develop the predicted model, which was verified and corrected by applying the collected data under Vegetation data of Spring and Autumn Pasture. The results showed that the growth indices of representative species can predict the aboveground biomass of themselves, other species and communities. The composite factor of plant height and coverage product was the best for predicting the population. The single factor of plant height and coverage was better than the compound factor in predicting the other populations of the four grasses and the compositae populations of the Potentilla bifurca. Six main species alone or two to six kinds of combining both predictable community biomass on the ground, but the product of 6 species of plant height and coverage to participate in the prediction of regression curve at the same time, decision coefficient is the largest, can explain community biomass of 89.50% of the variation on the ground, can be used as a typical alpine steppe community biomass optimal prediction model on the ground.

Grazing pressure and tree competition affect cattle performance and native pastures in Eucalypt woodlands of Queensland, north-eastern Australia

Context Well managed grazing pressure will optimise animal and pasture production, and preserve the soil to maintain a viable beef business on native pastures in eucalypt woodlands. Aims A cattle grazing experiment was established to measure animal and pasture performance under management practices used in the Aristida/Bothriochloa native pastures in central Queensland. Methods Performance of Brahman-cross steers and pastures were measured in an experiment with three grazing pressures by two tree densities in a Eucalyptus populnea woodland in north-eastern Australia over 8 years in paddocks of 4–18 ha. Key results At low grazing pressure with trees killed by herbicide (‘cleared’), stocking rate increased 35% as pasture composition and biomass improved over 8 years. At low grazing pressure where treed, stocking rate remained constant, however, at high grazing pressure where treed, it was reduced after 4 years. The annual liveweight gain increased from 0.37 to 0.45 to 0.51 kg/head.day as grazing pressure was reduced from high to medium to low grazing pressure respectively, and across grazing pressures it decreased from 0.49 where cleared to 0.39 kg/head.day where treed. Liveweight gain per hectare increased under low grazing pressure and declined at medium and high pressures. Body condition scores responded positively to lower grazing pressure and a lack of tree competition to pastures. This treatment combination also produced higher animal sale values. Pasture biomass, basal area and ground cover were all affected negatively by increasing grazing pressure. Conclusions Grazing 25% of autumn pasture improved dry matter production, species composition and land condition, and increased steer growth rates, body condition and their market value. This grazing pressure produced an increasing trend in stocking rates relative to the decline at higher grazing pressures. Higher liveweight gain/ha was produced initially at high grazing pressure (75% utilisation), however, after 4 years animal condition and pastures deteriorated, requiring a reduction in stocking rate to maintain the condition of both the remaining animals and the pastures. Managing tree competition to pastures is necessary to maintain the higher animal production potential. Implications This objective information demonstrates the benefits for cattle, pastures and long-term economic outcomes of managing for conservative grazing pressure and controlling tree competition to pasture in this woodland. Applying these findings can improve beef business outcomes and provide management groups with objective educational resources.

Real-Time Monitoring of Self-Fed Supplement Intake, Feeding Behaviour, and Growth Rate as Affected by Forage Quantity and Quality of Rotationally Grazed Beef Cattle.

Simple SummaryIn grazing systems, the use of novel technologies such as electronic feeders and automatic weighing systems enables collection of daily data of cattle feeding behaviour and growth. These technologies can be useful to study animal response to varying forage quantity and quality within and throughout grazing periods and seasons. The aim of this 254-day experiment was to investigate the effect of forage type, quantity, and quality on the consumption of a self-fed supplement (molasses-lick blocks (MLB)) and on the growth rate and feeding behaviour of grazing beef cattle. Results indicated that type and amount of forage affect MLB intake and feeding behaviour. Thus, when feed availability is low (e.g., forage on the paddock is depleted), animals increase consumption of and number and duration of visits to the supplementary feed. The use of MLB only improved growth rate of cattle when animals grazed sorghum and pasture or were fed oaten hay. Monitoring the feeding behaviour of animals around MLB reflects changes in forage quantity and quality.Supplement intake and liveweight (LW) data were collected daily and remotely by digital in-paddock technologies (electronic feeder (EF) and walk-over-weighing scale (WOW)) to study the effect of forage quantity and quality on the intake of a self-fed supplement (molasses-lick blocks (MLB)), LW, liveweight change (LWC), and feeding behaviour of grazing beef cattle. Fifty-two crossbred weaners were rotationally grazed or fed for 254 days on different forages: sudangrass (SG), autumn pastures (P), winter pastures with concentrate (P+C), oat crops (OC), lucerne hay (LH), and oaten hay (OH). Forage quantity and quality were measured on the day of entry (high feed availability) and exit (low feed availability) stages of grazing or hay delivery. The intake of MLB was 111% higher (p < 0.05) at low compared to high feed availability, and this was also reflected in the feeding behaviour of animals (e.g., greater feeding frequency and rate). Moreover, there was a large temporal variability of daily MLB intake (Coefficient of variation (CV) = 146.41%). Supplementing MLB improved LWC only with SG, P, or OH (p < 0.05). The behaviour of animals around MLB reflects changes in feed quantity and quality and could be used to enhance cattle grazing and nutritional management in real time.

Slope failure induced by cold snap and continuous precipitation in the seasonal frozen area of Qinghai-Tibet Plateau

A slope failure of roughly 26,000 m3 occurred on September 7th, 2017 in the upper layer of a north-facing slope at Autumn Pasture in Zhimei Village, Chenduo County, Tibetan Autonomous Prefecture of Yushu (34°07′02.26″N, 96°37′10.90″E). Field investigations have indicated there is no continuous or discontinuous permafrost found in this area. The earth slope is susceptible to seasonal frost in freezing season and heavy rainfall in raining season. Hence, we hypothesized that the slope failure was induced by increasing pore water pressure at the basal surface, which resulted from the combined effect of a frozen upper layer and accumulated infiltrated soil water. With the accessible meteorological data from National Oceanic and Atmospheric Administration (NOAA), numerical software (CoupModel) was used to simulate the hydro-thermal state of the source area in order to explore the influence of atmospheric change and the triggering mechanism of slope failure. The simulation results indicate that an unexpected cold snap promoted the freezing process of the shallow soil layer, and the drainage of liquid water was impeded by this frozen layer. Accumulated downslope water at source area, namely the slope toe, led to the increasing of pore water pressure in the deeper parts of the soil. The source area is located in the catchment area, where water accumulated from surrounding slopes. Increased gravity of the upper layer resulting from downslope infiltrating soil water, and decreased shear strength of basal surface both contributed to the slope instability. The failure illustrated the influence of seasonal frost and sustained precipitation on mass wasting in Qinghai-Tibet Plateau (QTP).

The Effect of Husbandry and Management System on Sudan Desert Sheep Leather Production and Quality

This trail is aimed to demonstrate the effect of husbandry and management system on Sudan desert sheep performance and skin quality. For this purpose a questionnaire was designed and distributed randomly for 20 sheep breeders in each of the five chosen sheep breed area’s (Total of 100 ques.). The questionnaire include beside the personal data, twenty two (22) questions mainly about; system of feeding and application methods in each season, husbandry systems in each season , the main effective treatments on skins quality and common skin diseases and external parasites. The results revealed that, most of Sudan desert sheep owners or breeders were illiterate and most of them were herder 48.0%, while 37.5% were herder and farmer at the same time. All respondents confirmed that the open system depending on natural grazing was the main h usbandry and management system in all study target area. In autumn sheep depends totally on natural pasture grazing, while in winter sheep partly fed on natural grazing and the breeders complete it's feeding depending on the litter that remained from food crops after harvesting. Sudan desert sheep breeder in summer are using their stock of forage hay that collected either during the rainy season from good growing autumn pastures or from agricultural byproducts such as sorghum and sesame straw or groundnut r esiduals. The additional diets is varies by the variation of Sudan desert sheep locations. sometimes when forage are limited and for marketing purposes Sudan desert sheep breeders adding little amount or uncountable amount of sorghum grains, cotton seed ca kes, groundnut seed cake as finisher diet concentrate beside agricultural byproducts such as groundnut byproduct hay, sorghum byproduct hay and sesame byproduct hay for the herd that offered for sale or for fleshing or steaming up ewes during lambing seaso n. Branding is the most common and known damage in skins generally. Also some animal breeder's belief that by means of hot iron branding some animals may acquire immunity against certain diseases. The respondents attributed causes of mechanical damages of skins of animals on range land mainly to the domination of thorny bushes and grass with hairy and spiny seeds in pastures. External parasites and skin diseases cause most of skins damages and wastages in Sudan generally. Sheep pox spreads on sheep skins wi th high rates (88%). On the other hand, mange are resulting in (8%) of sheep skins infections. However, ticks infect most of sheep skins (80%), when Lice infection estimated at 20% of sheep skins.

Supplementation of Merino ewes with vitamin E plus selenium increases α-tocopherol and selenium concentrations in plasma of the lamb but does not improve their immune function

Vitamin E and selenium have been reported to improve immune function across a range of species. Ewes lambing on poor-quality dry pasture in autumn in Western Australia are at risk of being deficient in vitamin E and selenium at lambing thus predisposing their lambs to deficiencies and increasing the risk of infection and disease. This study tested the hypotheses that (i) supplementation of autumn-lambing ewes with vitamin E plus selenium in late gestation will increase the concentrations of vitamin E and selenium in plasma in the ewe and lamb and (ii) that the increased concentrations of vitamin E and selenium in plasma in the lambs will improve their innate and adaptive immune responses and thus survival. Pregnant Merino ewes were divided into a control group (n=58) which received no supplementation or a group supplemented with vitamin E plus selenium (n=55). On days 111, 125 and 140 of pregnancy ewes in the vitamin E plus selenium group were given 4 g all-rac-α-tocopherol acetate orally. On day 111 the ewes were also given 60 mg of selenium as barium selenate by subcutaneous injection. The concentrations of α-tocopherol and selenium were measured in ewes and/or lambs from day 111 of pregnancy to 14 weeks of age±10 days (weaning). Immune function of the lamb was assessed by analysing the numbers and phagocytic capacities of monocytes and polymorphonuclear leucocytes and plasma IgG and anti-tetanus toxoid antibody concentrations between birth and 14 weeks of age±10 days. Maternal supplementation with vitamin E plus selenium increased the concentration of α-tocopherol in plasma (1.13 v. 0.67 mg/l; P<0.001) and selenium in whole blood (0.12 v. 0.07 mg/l; P<0.01) of the ewes at lambing compared with controls. Supplementation also increased the concentration of α-tocopherol (0.14 v. 0.08 mg/l; P<0.001) and selenium (0.08 v. 0.05 mg/l; P<0.01) in lambs at birth compared with controls. There was no significant effect of supplementation on immune function or survival in the lambs.

Effect of Season on Diet Composition, Dry Matter Intake and Digestibility in Adult Sheep Grazed on Sub-Alpine Pastures of Kashmir Valley

The present study was designed to analyzes the seasonal variations in diet composition, nutrient intake and digestibility of sub-alpine pastures of Kashmir valley in mature sheep. The experiment was conducted in two seasons of summer (June) and autumn (October) at two locations (MRCSG, Shuhama, Location-I and SBF, Dachigam, Location-II) having different vegetative covers. The apparent digestibility of most of the nutrients was higher (P<0.05) in summer than in autumn season. The ME, TDN and DCP contents of the summer pastures were higher (P<0.05) than the autumn pastures at both locations. Dry matter intake from the summer pastures was higher than the winter pastures at both locations and their corresponding digestibilities also followed the same trend. Calcium intake was higher (P<0.05) in summer at location-I compared to location-II. However, P intake (g/d) from both pastures was higher (P<0.05) in summer than autumn season. The TDN intake (g/d) was deficient by 7% and ME intake (Mcal/d) by 5% in comparison to ICAR feeding standard (2013) in summer season at location-I while in autumn season the deficiency increased to 44 and 43%, respectively. Location-II offered adequate nutrients to animals in summer season while in autumn season the deficiency of 24% in TDN intake (g/d) and 22% in ME intake (Mcal/d) was observed. The DCP intake (g/d) was deficit by 12% at location-I in the autumn season while in summer season it was adequate at both the locations. Hence, the pastures at both the locations were deficient in energy especially in autumn season.

Live weight gain, urinary nitrogen excretion and urination behaviour of dairy heifers grazing pasture, chicory and plantain

SUMMARYThe objective of the present study was to investigate live weight (LW) gain, urinary nitrogen (UN) excretion and urination behaviour of dairy heifers grazing pasture, chicory and plantain in autumn and spring. The study comprised a 35-day autumn trial (with a 7-day acclimation period) and a 28-days spring trial (with a 7-day acclimation period). For each trial, 56 Friesian × Jersey heifers were blocked into five dietary treatments balanced for their LW and breeding worth (i.e. genetic merit of a cow for production and reproduction): 1·00 perennial ryegrass–white clover pasture (PA); 1·00 chicory (CH); 1·00 plantain (PL); 0·50 pasture + 0·50 chicory (PA + CH); and 0·50 pasture + 0·50 plantain (PA + PL). A fresh allocation of the herbage was offered every 3 days with allowance calculated according to feed requirement for maintenance plus gain of 1·0 kg LW/day. In both trials, LW gain was lower on CH than other treatments. In the spring trial, UN concentration and UN excretion were lower in CH and PL than other treatments. In autumn, a higher urination frequency was observed over the first 6 h after forage allocation in CH and PA + CH than other treatments. Data from the present study indicate that feeding CH alone limited heifer LW gain. However, heifers grazing swards containing chicory (CH and PA + CH) and plantain (PL and PA + PL) had the potential to lower nitrous oxide emissions and nitrate leaching from soil compared with heifers grazing PA, by reducing N loading in urine patches.

Diurnal variation in urine nitrogen and creatinine concentrations from lactating cows grazing ryegrass-dominant pasture in autumn and late spring–summer

In dairy production systems based on grazed pasture, urine patches are the main source of nitrogen (N) losses via leaching and gaseous emission pathways. The volume and N concentration of urine influences the amount of N in a urine patch. We conducted systematic urine sampling to determine the diurnal variation in concentrations of N and creatinine (a proxy for urine volume), and the N : creatinine ratio, to identify the sampling required for accurately estimating the daily mean concentrations of N and creatinine. Nine groups (n = 6) of multiparous Friesian and Friesian × Jersey cows in autumn (220 ± 26 days-in-milk, milked twice daily) and nine groups (n = 6) in late spring–summer (228 ± 24 days-in-milk, milked once daily) were sequentially withdrawn from the farm herd at approximately weekly intervals and each group was offered a fresh allocation of ryegrass-dominant pasture twice daily after milking for 3 days (including at the equivalent time in the afternoon in late spring–summer when they were milked once daily). For each of the 18 different groups of cows, individual urine samples were collected on Day 3 at 1100 hours, 1500 hours (afternoon milking), 1800 hours and 0700 hours (the following morning milking), and, subsequently, analysed for total N and creatinine concentrations. In autumn, urine-N concentrations were higher (P = 0.0002) at 1800 hours (5.8 g N/L) than they were at 1500 hours or 0700 hours (mean of 4.2 g N/L). In late spring–summer, the concentrations were higher (P &lt; 0.001) at 1100 hours (8.0 g N/L) than they were at 1500 hours, 1800 hours or 0700 hours (mean of 6.3 g N/L). The urine N : creatinine ratio was 214 mol/mol in autumn and 148 mol/mol in late spring–summer, but did not vary among sampling times during the day. The highest concentrations of N were in urine samples collected ~3 h post-allocation of fresh feed when cows had grazed actively and consumed the majority of the herbage available. For accurate estimates of the daily mean urine N concentration, sample collections should be timed to encompass this diurnal variation. For the N : creatinine ratio, which was more stable through the day, the timing of sample collection is less important for estimating a daily mean.

Growth of weaned Friesian bull calves on a herb sward or with concentrate supplementation during late summer and early autumn

ABSTRACTGrowth rates of weaned bull calves in late summer/early autumn can be low in a ryegrass/white clover-based system. This experiment compared the liveweight gain of weaned bull calves (n = 18 per treatment per year, in 3 replicates of 6 bulls) grazed on a herb sward comprised of chicory, plantain, red clover and white clover with bulls grazed on either pasture supplemented with 1.8 kg DM/day of concentrate, or pasture without supplementation. The experiment was repeated over three years. Bulls grazed on the herb sward grew faster (P < .05) than bulls grazed on pasture with or without concentrate supplementation. Liveweight gain of bulls grazed on pasture was less than for bulls supplemented with concentrate in two of the three years (P < .05). A herb sward is a better quality alternative to late summer/early autumn pasture, and could be used to increase liveweight gain of bulls during this period.

Effects of summer turnip forage cropping and pasture renewal on nitrogen and phosphorus losses in dairy farm drainage waters: A three-year field study

Spring cultivation of soil under long-term pasture to grow summer forage followed by autumn pasture renewal is a common practice on New Zealand dairy farms. Although this practice is widely used, there is limited research available on the impact that it has on nutrient losses to water. This three-year field study was conducted to quantify the effects of summer forage cropping and autumn re-grassing on nitrogen (N) and phosphorus (P) losses in mole and pipe drainage from a Pallic Soil in the Manawatu region of New Zealand. The two treatments compared were a continuation of long-term grazed pasture, and long-term pasture that was cultivated in spring, sown into turnips as a summer forage for dairy cows, followed by autumn re-grassing. Both treatments where located on artificially drained field plots.Summer forage cropping and autumn re-grassing increased total nitrogen measured in drainage water by 21kgN/ha in total over the three seasons monitored, which was a 84% increase compared to long-term pasture. Approximately three-quarters of this increase happened during the two months following spring cultivation, which was influenced by an atypically wet late spring/early summer period that extended the drainage season. It is estimated that if the spring cultivation had been conducted in a year with a more typical drainage season, then the additional total nitrogen losses are likely to have been about 6.9kgN/ha. Overall losses of total phosphorus in drainage were low for both treatments during the study period, with the forage cropping and autumn re-grassing increasing total phosphorus losses in drainage by 0.36kg P/ha over the duration of the study, which was 77% higher than the long-term pasture treatment.

Comparison of aquaporin-1 expression between yak (Bos grunniens) and indigenous cattle (Bos taurus) in the Qinghai–Tibetan Plateau

Aquaporins (AQPs) are a large family of integral membrane proteins that facilitate the transport of water through the biomembranes. AQP1, one of the 13 AQPs identified in mammals, is distributed in various tissues and organs, and plays an important role in body water homeostasis. The objectives of the present study were to identify the expression of aquaporin-1 (AQP1) in the kidney, rumen and parotid gland of yaks, and to quantify whether the protein abundance of AQP1 is species specific between yak (Bos grunniens) and indigenous cattle (Bos taurus). Three 3-year-old castrated males (156 ± 6.8 kg of bodyweight) of each of three genotypes, namely, yak, indigenous cattle and the crossbred between the two (Bos taurus♂ × Bos grunniens♀), were used; all animals were grazed in the same autumn pasture of the Qinghai–Tibetan Plateau, China. Western blot results detected (1) 28-kDa unglycosylated AQP1 in the kidney, rumen and parotid gland of all three genotypes, 40-kDa glycosylated AQP1 in renal cortex and medulla. (2) Yaks expressed less 28-kDa AQP1 protein in the outer cortex (P &amp;lt; 0.05), significantly more in the outer medulla (P &amp;lt; 0.01), and slightly more in the ventral rumen (P = 0.088) than did cattle. No difference was observed in the dorsal rumen and parotid gland (P &amp;gt; 0.10). In conclusion, the present study is the first to confirm the presence of AQP1 in bovine rumen and parotid gland and identified its expression in yaks. Abundance of AQP1 protein in yak kidney showed some difference from indigenous cattle. This could provide a new perspective to explain some adaptive mechanisms of yaks to the harsh environment in the Qinghai–Tibetan Plateau.