Supplementation of steers grazing Stylosanthes hamata pastures at Katherine, Northern Territory

1988 ◽  
Vol 28 (6) ◽  
pp. 669 ◽  
Author(s):  
WH Winter
Keyword(s):  
Rock Phosphate ◽  
Perennial Grass ◽  
Dry Season ◽  
Fertility Level ◽  
Wet Season ◽  
Active Growth ◽  
Weight Losses ◽  
Stylosanthes Hamata ◽  
Brahman Steers ◽  
Native Perennial Grass

Native perennial grass pastures were oversown with Stylosanthes hamata cv. Verano at 3 fertility levels, i.e, without fertiliser or with suboptimal levels of superphosphate or rock phosphate. Brahman steers, of varying ages, grazed the pastures and their responses to fertility level and direct supplementation with phosphorus and sulfur were determined over 4 years. Phosphorus supplementation doubled liveweight gains during the early and late wet season periods to about 0.9 and 0-7 kg/day, respectively. Pasture fertility level did not affect gains in the early wet season in most years but superphosphate increased the late wet season gains by about 0.1 kg/day. Small weight losses usually occurred in all treatments during the early dry season, with losses increasing with animal age. Weight losses were highest during the late dry season, particularly for the older, phosphorus supplemented, steers. This response was attributed to size rather than to age or supplementation per se. Sulfur supplementation had no effect upon liveweight gain or upon the pastures at any time. In unfertilised pastures, Verano increased to about 25% of the dry matter composition whilst pastures fertilised with superphosphate and rock phosphate became legume dominant after 2 and 3 years, respectively. Fertiliser also increased the nitrogen, phosphorus and sulfur concentrations in the forage, particularly the Verano, with superphosphate more effective than rock phosphate. In pastures where steers were supplemented with phosphorus there was a higher proportion of the naturalised legume Alysicarpus vaginalis and a lesser quantity of forage on offer. Blood inorganic phosphate and rib cortical thickness were reliable indicators of responsiveness of steers to phosphorus supplementation when measured during, or immediately after, the period of active growth.

Evaluation of management options for increasing the productivity of tropical savanna pastures. 3. Trees

1989 ◽  
Vol 29 (5) ◽  
pp. 631 ◽  
Author(s):  
WH Winter ◽  
JJ Mott ◽  
RW McLean
Keyword(s):  
Dry Season ◽  
Perennial Grasses ◽  
Fertility Level ◽  
Wet Season ◽  
Management Options ◽  
Themeda Triandra ◽  
Weight Losses ◽  
Nitrogen Concentrations ◽  
The Mean ◽  
Stocking Rates

The effect of killing trees upon the production and quality of native perennial grasses, Themeda triandra, Chrysopogon fallax, Sehima nervosum, and Sorghum plumosum, and oversown legumes from the genus Stylosanthes, was studied over 4 years at Katherine, in the semi-arid tropics of northwestern Australia. The pastures were either unfertilised or received low inputs of superphosphate, and for each fertility level were grazed at 3 stocking rates. At no time were legume yields affected by killing the trees but, in the first 3 years, the amount of grass was approximately twice as much when the trees were killed. During this period the mean grass yields declined 4-5 fold from about 2.2 t/ha. By the fourth year the advantage from tree killing upon grass yield was apparent only at the lowest stocking rates at each fertility level. Nitrogen concentrations of the grasses and legumes, with the exception of S. hamata, were increased 7 and 10% respectively above the mean annual values of 0.89 and 1.75% where the trees were killed, while the phosphorus and sulfur concentrations were not affected. Tree killing had no effect upon wet season liveweight gains during the last 2 years of the experiment. However, there were some benefits during the dry season when weight losses were lower for most treatments during the early dry season (June-September) and also lower for the lowest stocking rate treatment without fertiliser during the late dry season (October-November).

Diet selection and liveweight performance of steers on Stylosanthes hamata-native grass pastures

1980 ◽  
Vol 31 (2) ◽  
pp. 379 ◽  
Author(s):  
CJ Gardener
Keyword(s):  
Stem Elongation ◽  
Perennial Grass ◽  
Diet Selection ◽  
Similar Rate ◽  
Dry Season ◽  
Wet Season ◽  
Native Grass ◽  
Stylosanthes Hamata ◽  
Large Bulk ◽  
Native Pasture

Diet selection in S. hamata-native grass pastures was studied over 25 months at Lansdown, north Queensland, In oesophageally fistulated steers. The results were uscd to interpret the relationship between winter rainfall and liveweight gain of steers on pastures with and without S. hamata. Steers selected green grass leaf early in the wet season (December-February), but preferred S. hamata in March when stem elongation and flowering occurred in the native grasses. They then continued to eat a high proportion of legume during the dry season until rain fell. At Lansdown, this may occur from 4 to 23 weeks after the pastures hay off. After the rain, the steers ignored the large bulk of mouldy dry legume, selecting instead both green and dry grass. Seed and green leaf of S. hamata made their greatest contribution to the diet at the end of the wet season when retained on the standing plant and easily accessible to cattle. Small amounts of seed and dried leaf were licked off the ground before rain fell. The nitrogen content of the diet in the S. hamata-native grass pastures rose to a peak in April and did not fall below 1.0% during the study. The level in July was twice that recorded for the native pasture. Cattle gained weight during the wet season at a similar rate for all pastures. After March steers on S. hamata-native pasture continued to gain weight longer onto the dry season than those on native pasture in three out of four years. Much of the additional weight gains of steers on S. hamata were lost with the advent of winter rain, especially at the high stocking rate from which the perennial grass component had been lost. The value of S. hamata cv. Verano in the greatly differing climatic environments existing in northern Australia is considered.

The growth of Urochloa accessions in grazed swards with Stylosanthes near Townsville, north Queensland

1985 ◽  
Vol 25 (1) ◽  
pp. 61 ◽  
Author(s):  
JG McIvor
Keyword(s):  
Perennial Grass ◽  
Grazing Pressure ◽  
First Year ◽  
Wet Season ◽  
Low Level ◽  
Seasonally Dry ◽  
Stylosanthes Hamata ◽  
Annual Grasses ◽  
Tropical Areas ◽  
High Yields

Six Urochloa accessions (U. mosambicensis cv. Nixon, CPI 46876, CPI 47 167 and U. oligotricha CPI45607, CPI47122, CPI 47 124) were grown with Stylosanthes hamata cv. Verano and S. scabra cv. Seca in individually fenced, fertilized swards near Townsville, Queensland, for 5 years. The swards were grazed by single steers for 2 days at 6-weekly intervals (equivalent to a stocking rate of 1 steedha). Two grazing regimes were used: grazing throughout the year (high grazing pressure); and grazing during the dry season only (low grazing pressure). There was good establishment of Verano but Seca and all Urochloa accessions established poorly. In subsequent years there were few U. oligotricha seedlings but there were substantial numbers of U. mosambicensis seedlings. Most seedlings died during their first year and in the final year of the study the number of perennial Urochloa plants ranged from 1 /m2 (CPI 47 122) to 1 7/m2 (CPI 46876). Yield and proportion of Urochloa were low during the first year but later increased for the U. mosambicensis accessions, particularly CPI 46876, which out-yielded all other accessions in the final 3 years. High yields of Urochloa were associated with low yields of Verano and annual grasses. High grazing pressure reduced the total pasture yield. Verano was always a major component, especially at high grazing pressure. The proportion of Seca increased from an initial low level but then declined again to a very low level. There was very little native perennial grass at high grazing pressure. The proportion of grass in the swards was highest at the start of the wet season and then declined; in contrast, the proportion of legume increased during the wet season. The value of Urochloa species in seasonally dry tropical areas and their management in pastures are discussed.

Effect of feeding forage characteristic of wet- or dry-season tropical C4 grass in northern Australia, on methane production, intake and rumen outflow rates in Bos indicus steers

2017 ◽  
Vol 57 (10) ◽  
pp. 2033 ◽  
Author(s):  
L. A. Perry ◽  
R. Al Jassim ◽  
J. B. Gaughan ◽  
N. W. Tomkins
Keyword(s):  
Methane Production ◽  
Volatile Fatty Acids ◽  
Day Treatment ◽  
Bos Indicus ◽  
Open Circuit ◽  
Dry Season ◽  
Wet Season ◽  
Total N ◽  
Acid Detergent Fibre ◽  
Brahman Steers

Methane production (MP) from Bos indicus steers fed Chloris gayana hay characteristic of the ‘dry season’ (LQH), and a fresh Urochloa mosambicensis grass (PAS) or a C. gayana hay (HQH) characteristic of the ‘wet’ season was determined. A longitudinal feeding trial incorporated a 42-day covariate period (P1) in which Brahman steers (total n = 12) were fed ad libitum LQH (g/kg DM: crude protein (CP) 25; acid detergent fibre expressed exclusive of residual ash (ADFom) 487; DM digestibility (DMD) 380) followed by a 42-day treatment period where steers (n = 4 in each) were randomly assigned to PAS, HQH or remained on LQH (control). The diet composition in P2 was HQH (g/kg DM: CP 88; ADFom 376; DMD 590), PAS (g/kg DM: CP 90; ADFom 324; DMD 630) and LQH (g/kg DM: CP 31; ADFom 461; DMD 410). For each period, on Days 35–41, individual dry-matter intakes (DMI), rumen fermentation parameters and both fluid and particulate fractional rumen outflow rates were measured. On Days 41 and 42, MP was determined using open-circuit respiration chambers. There were diet effects on MP, DMI, volatile fatty acids, and ammonia-N. Both PAS- and HQH-fed steers had greater MP (g/day; P < 0.05) and DMI (P < 0.05) than did those fed LQH, but a lower MP per kilogram DMI digested. The use of predictive equations compared with measured data confirmed prior observations that MP from tropical grasses in the northern Australian rangelands may be overestimated using the current equations for greenhouse gas accounting.

A note on the effect of dry season feeding treatment on the subsequent growth at pasture during the wet season of Brahman steers

1988 ◽  
Vol 47 (3) ◽  
pp. 501-504 ◽  
Author(s):  
J. Wadsworth
Keyword(s):  
Sugar Cane ◽  
Compensatory Growth ◽  
Live Weight ◽  
Dry Season ◽  
Single Group ◽  
Subsequent Growth ◽  
Wet Season ◽  
Weight Gains ◽  
Brahman Steers

An experiment was carried out over successive years (1982 and 1983) to measure the extent to which live-weight advantage as a result of feeding in the dry season was maintained during the subsequent wet season at pasture. Two ages of Brahman steer (weaners and yearlings) were kept on three dry season treatments (molasses, sugar cane or grazing only) from January to May and then turned out to pasture as a single group until November. Although the molasses and sugar cane treatments produced significantly higher live-weight gains during the dry season the resultant weight advantage at turn-out was largely reduced during the wet season due to compensatory growth exhibited by previously restricted animals. Yearlings were less able to compensate than weaners.

An analysis of cattle live-weight changes on tropical grass pasture during the dry and early wet seasons in northern australia: 1. The nature of weight changes

1983 ◽  
Vol 101 (1) ◽  
pp. 17-24 ◽  
Author(s):  
R. W. McLean ◽  
R. L. McCown ◽  
D. A. Little ◽  
W. H. Winter ◽  
R. A. Dance
Keyword(s):  
Live Weight ◽  
Dry Season ◽  
Gut Contents ◽  
Northern Australia ◽  
Weight Changes ◽  
Wet Season ◽  
Tissue Water ◽  
Weight Losses ◽  
Gut Fill ◽  
Total Body

SUMMARYStudies were conducted to elucidate the nature and cause of the drastic losses of live weight of cattle grazing buffel grass pastures after first rains at the end of the dry season in northern Australia. This paper examines trends in weight and body composition during the dry and early wet seasons; it shows that although most of the loss in fasted live weight occurred just after first rain, most of the loss of body solids, mainly fat, had already occurred by this time. Losses of body solids in the dry season were not fully reflected in live-weight losses because of increases in total body water and in gut ‘fill’. The greatly accelerated weight loss in the period following first rain appears to have been due mainly to a large reduction in gut contents. Empty-body weight actually increased during this period owing to increases in tissue water. Continuation of this trend in tissue water into the early wet season resulted in the rate of live-weight gain greatly exceeding that of body solids.

scholarly journals The seasonal changes of the gut microbiome of the population living in traditional lifestyles are represented by characteristic species-level and functional-level SNP enrichment patterns

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Xue Zhu ◽  
Jiyue Qin ◽  
Chongyang Tan ◽  
Kang Ning
Keyword(s):  
Gut Microbiome ◽  
Seasonal Changes ◽  
Dry Season ◽  
Urban Setting ◽  
Snp Analysis ◽  
Wet Season ◽  
Human Gut ◽  
Human Gut Microbiome ◽  
Genome Level ◽  
Prevalent Species

Abstract Background Most studies investigating human gut microbiome dynamics are conducted on humans living in an urban setting. However, few studies have researched the gut microbiome of the populations living traditional lifestyles. These understudied populations are arguably better subjects in answering human-gut microbiome evolution because of their lower exposure to antibiotics and higher dependence on natural resources. Hadza hunter-gatherers in Tanzania have exhibited high biodiversity and seasonal patterns in their gut microbiome composition at the family level, where some taxa disappear in one season and reappear later. Such seasonal changes have been profiled, but the nucleotide changes remain unexplored at the genome level. Thus, it is still elusive how microbial communities change with seasonal changes at the genome level. Results In this study, we performed a strain-level single nucleotide polymorphism (SNP) analysis on 40 Hadza fecal metagenome samples spanning three seasons. With more SNP presented in the wet season, eight prevalent species have significant SNP enrichment with the increasing number of SNP calling by VarScan2, among which only three species have relatively high abundances. Eighty-three genes have the most SNP distributions between the wet season and dry season. Many of these genes are derived from Ruminococcus obeum, and mainly participated in metabolic pathways including carbon metabolism, pyruvate metabolism, and glycolysis. Conclusions Eight prevalent species have significant SNP enrichments with the increasing number of SNP, among which only Eubacterium biforme, Eubacterium hallii and Ruminococcus obeum have relatively high species abundances. Many genes in the microbiomes also presented characteristic SNP distributions between the wet season and the dry season. This implies that the seasonal changes might indirectly impact the mutation patterns for specific species and functions for the gut microbiome of the population that lives in traditional lifestyles through changing the diet in wet and dry seasons, indicating the role of these variants in these species’ adaptation to the changing environment and diets.

scholarly journals Seasonal Climate Impacts on Vocal Activity in Two Neotropical Nonpasserines

Diversity ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 319
Author(s):  
Cristian Pérez-Granados ◽  
Karl-L. Schuchmann
Keyword(s):  
Air Temperature ◽  
Daily Rainfall ◽  
Climatic Conditions ◽  
Dry Season ◽  
Climate Impacts ◽  
Calling Behavior ◽  
Wet Season ◽  
Focal Species ◽  
Calling Activity ◽  
Vocal Activity

Climatic conditions represent one of the main constraints that influence avian calling behavior. Here, we monitored the daily calling activity of the Undulated Tinamou (Crypturellus undulatus) and the Chaco Chachalaca (Ortalis canicollis) during the dry and wet seasons in the Brazilian Pantanal. We aimed to assess the effects of climate predictors on the vocal activity of these focal species and evaluate whether these effects may vary among seasons. Air temperature was positively associated with the daily calling activity of both species during the dry season. However, the vocal activity of both species was unrelated to air temperature during the wet season, when higher temperatures occur. Daily rainfall was positively related to the daily calling activity of both species during the dry season, when rainfall events are scarce and seem to act as a trigger for breeding phenology of the focal species. Nonetheless, air temperature was negatively associated with the daily calling activity of the Undulated Tinamou during the wet season, when rainfall was abundant. This study improves our understanding of the vocal behavior of tropical birds and their relationships with climate, but further research is needed to elucidate the mechanisms behind the associations found in our study.

scholarly journals Inorganic Nitrogen Production and Removal along the Sediment Gradient of a Stormwater Infiltration Basin

Water ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 320
Author(s):  
Qianyao Si ◽  
Mary G. Lusk ◽  
Patrick W. Inglett
Keyword(s):  
Removal Efficiency ◽  
N Mineralization ◽  
Inorganic Nitrogen ◽  
Dry Season ◽  
Pollutant Removal ◽  
Net N Mineralization ◽  
Wet Season ◽  
Inorganic N ◽  
N Removal ◽  
Stormwater Infiltration

Stormwater infiltration basins (SIBs) are vegetated depressions that collect stormwater and allow it to infiltrate to underlying groundwater. Their pollutant removal efficiency is affected by the properties of the soils in which they are constructed. We assessed the soil nitrogen (N) cycle processes that produce and remove inorganic N in two urban SIBs, with the goal of further understanding the mechanisms that control N removal efficiency. We measured net N mineralization, nitrification, and potential denitrification in wet and dry seasons along a sedimentation gradient in two SIBs in the subtropical Tampa, Florida urban area. Net N mineralization was higher in the wet season than in the dry season; however, nitrification was higher in the dry season, providing a pool of highly mobile nitrate that would be susceptible to leaching during periodic dry season storms or with the onset of the following wet season. Denitrification decreased along the sediment gradient from the runoff inlet zone (up to 5.2 μg N/g h) to the outermost zone (up to 3.5 μg N/g h), providing significant spatial variation in inorganic N removal for the SIBs. Sediment accumulating around the inflow areas likely provided a carbon source, as well as maintained stable anaerobic conditions, which would enhance N removal.

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