The productivity of breeding ewes grazing on lucerne or grass and clover pastures on the tablelands of Southern Australia. III. Lamb mortality and weaning percentage

1984 ◽  
Vol 35 (5) ◽  
pp. 709 ◽  
Author(s):  
JR Donnelly
Keyword(s):  
Early Spring ◽  
Practical Significance ◽  
Cold Weather ◽  
Late Winter ◽  
Maternal Weight ◽  
Risk Of Death ◽  
Probability Of Death ◽  
The Difference ◽  
Stocking Rates

Weaning percentage and perinatal mortality of lambs born in late winter or early spring to Merino and Border Leicester x Merino ewes grazing at several stocking rates on lucerne or phalaris-clover pastures were measured over 2 years. Weaning percentages for mature crossbred ewes declined linearly from 136 lambs per 100 ewes joined when stocked at 9 ha-1 to 100 for those at 18 ha-1. For mature Merino ewes, the values were 109 and 70 respectively. Weaning percentages were similar on lucerne and phalaris pastures, although 8% more lambs were born to ewes grazing on phalaris; higher mortality in lambs born as multiples eliminated the difference. Death from exposure during the first 3 days of life was the most important cause of lamb losses. For lambs born as singles to Merino ewes the probability of death from exposure was up to 0.4, and reached 0.6 for lambs born as multiples. For single and multiple lambs born to crossbred ewes equivalent probabilities were 0.25 and 0.4 respectively. These probabilities were reduced if maternal weight was high at lambing, the reduction being of practical significance in very cold weather, particularly if the proportion of multiple births was high. Under mild conditions, where the probability of death from exposure was low, reductions in mortality from high ewe weight at lambing were of little consequence. Long-term weather records kept at the experimental site near Canberra show that a high risk of death in new-born lambs is likely from early June to mid-September. Throughout this period deaths from exposure could be expected to exceed 30% in lambs born as multiples to Merino ewes.

scholarly journals Seasonal patterns of pasture production in the Bay of Plenty and Waikato

1991 ◽  
pp. 67-72
Author(s):  
J.A. Baars ◽  
G.J. Goold ◽  
M.F. Hawke ◽  
P.J. Kilgarriff ◽  
M.D. Rolm
Keyword(s):  
Growth Rates ◽  
Early Spring ◽  
Early Summer ◽  
Growth Patterns ◽  
Climatic Data ◽  
Large Contribution ◽  
Pasture Production ◽  
Summer Peak ◽  
The Difference

Patterns of pasture growth were measured on 3 farms in the Bay of Plenty (BOP) and at No2 Dairy (Ruakura Agricultural Centre) in the Waikato from 1989 to 199 1. A standardised trim technique with cages and 4-weekly cutting under grazing was used. Long-term seasonal growth patterns, using a predictive pasture model, were also simulated. Simulated pasture growth from long-term climatic data shows that pasture growth rates are higher in winter, early spring and late autumn in the BOP than the Waikato. However, the actual measurements over the 2 years show that pasture growth over the latter periods is lower at the BOP sites than at the Waikato site. In the BOP the spring peak is much later than in the Waikato while an early summer peak, with higher growth rates than in the Waikato, occurred in the BOP. No such summer peak was evident in the Waikato. The difference between the two regions is caused by the large contribution of subtropical grasses to sward production in summer and autumn, The prolific summer growth of subtropical grasses may explain the low ryegrass content and low pasture production in winter. The lower than expected autumn, winter, spring production may also becaused by low clover content, possibly a result of competition from subtropical grasses and a sulphur deficiency. The apparent low amount of nitrogen fixed by clover may explain the low rates of pasture production over the cooler season. Applications of nitrogen fertiliser may substantially increase dry matter production from April to September. Keywords pasture,simulation,subtropical grasses, Paspalum, Digitaria sanguinalis, growth rates

scholarly journals Changes in Maternal Weight 5–10 Years after a First Delivery

2012 ◽  
Vol 8 (5) ◽  
pp. 513-519 ◽  
Author(s):  
Sarah E Britz ◽  
Kelly C McDermott ◽  
Christopher B Pierce ◽  
Joan L Blomquist ◽  
Victoria L Handa
Keyword(s):  
Weight Loss ◽  
Black Women ◽  
Reproductive Factors ◽  
Education History ◽  
Healthy Weight ◽  
Maternal Weight ◽  
History Of ◽  
The Difference ◽  
Self Administered Questionnaire

Aim: The objective of this study was to identify maternal, obstetrical and reproductive factors associated with long-term changes in maternal weight after delivery. Materials & methods: Participants were enrolled in a longitudinal cohort study of maternal health 5–10 years after childbirth. Data were obtained from obstetrical records and a self-administered questionnaire. Weight at the time of first delivery (5–10 years prior) was obtained retrospectively and each woman's weight at the time of her first delivery was compared with her current weight. Results: Among 948 women, obesity was associated with race, parity, education, history of diabetes and history of cesarean at the time of first delivery. On average, the difference between weight at the time of first delivery and weight 5–10 years later was −11 kg (11 kg weight loss). In a multivariate model, black race and diabetes were associated with significantly less weight loss. Cesarean delivery, parity and breastfeeding were not associated with changes in maternal weight. Conclusion: Black women and those with a history of diabetes may be appropriate targets for interventions that promote a long-term healthy weight after childbirth.

Ecology of Small Mammals in Coastal Heathland at Anglesea, Victoria

1986 ◽  
Vol 13 (3) ◽  
pp. 397 ◽  
Author(s):  
BA Wilson ◽  
AR Bourne ◽  
RE Jessop
Keyword(s):  
Small Mammals ◽  
Vegetation Type ◽  
Habitat Preferences ◽  
Common Species ◽  
Early Spring ◽  
Late Winter ◽  
Habitat Differences ◽  
Antechinus Stuartii ◽  
Marked Decline ◽  
The Difference

Aspects of ecology and reproduction of small mammals in a heathland community near Anglesea were investigated in the field by means of mark-recapture trapping. Population size, animal movements and reproductive state were estimated. The floristic and structural habitat preferences were also determined. The most common species were Antechinus stuartii, A. minimus maritimus, Sminthopsis leucopus, Rattus fuscipes assimilis and R. lutreolus. For Antechinus the populations were maximal throughout February-June (A. stuartii) and December-June (A. minimus) inclusive. A marked decline in numbers of Antechinus during late winter and early spring was associated with the total loss of males from the population. The maximal numbers of animals (per hectare) were 21 (A. stuartii), 14 (A. m. maritimus), 14 (R. f. assimilis) 7 (R. lutreolus), and 8 (S. leucopus). Young were born to A. m. maritimus during August, and 1 month later to A. stuartii. R. f. assimilis bred during late winter and spring, and S. leucopus from September to November. None of the species showed an overall preference for any floristic or structural vegetation type. This study confirms male 'die-off' in A. m. maritimus. The data also indicate that the difference in breeding times of A. m. maritimus between Anglesea and Dartmoor, Vic., is due to climatic or habitat differences rather than to sympatry with A. stuartii.

On the Biology and Fishery of the Canadian Atlantic Halibut, Hippoglossus hippoglossus L.

1958 ◽  
Vol 15 (6) ◽  
pp. 1269-1311 ◽  
Author(s):  
F. D. McCracken
Keyword(s):  
Nova Scotia ◽  
Deep Water ◽  
Early Spring ◽  
Large Female ◽  
Late Winter ◽  
Atlantic Halibut ◽  
Large Numbers ◽  
Water Edge ◽  
Mature Fish

Exploratory fishing in the northern Gulf of St. Lawrence in 1945 and 1946 and off western Nova Scotia in 1947 caught 739 halibut, of which 229 were tagged and released. About 590 fish from the commercial fishery of the two regions were also examined.Larger, older halibut were caught in the northern part of the Gulf of St. Lawrence than off western Nova Scotia. Tagged halibut recaptures, size and age composition of commercial landings, and differences in rate of growth suggest generally separate stocks in the two regions.Younger, immature halibut were most available in shallower water; larger, mature fish usually in deep water. Most halibut were caught at temperatures between about 3° and 9 °C. Seasonal, inshore, relatively shallow water halibut fisheries in the northern part of the Gulf of St. Lawrence and off western Nova Scotia occur as the bottom water warms. Large female halibut predominate in such catches.Mature halibut, about 9 to 11 years and older, must spawn in late winter and early spring, probably along the deep-water edge of the banks. Mature halibut grow slowly though the females exceed the mature males and reach a much larger size. The faster-growing, immature halibut of both sexes grow at about the same rate.Halibut landings from ICNAF Subareas 3 and 4 which were at a low level between 1940 to 1948 increased sharply to about 13 million pounds in 1950. More recent landings approximate the long-term annual average of about 5 million pounds. Changes in the level of landings are related to changes in the magnitude of the Canadian fishery which, since 1940, has produced most of the halibut from Subareas 3 and 4.Offshore and inshore fisheries specifically for large halibut produce most of the landings. Catches of halibut taken incidentally in other fisheries contribute little by weight but take large numbers of small, faster-growing individuals. With a continuation of present fishing practices and intensities an annual yield of about 5 million pounds may be expected to continue, but some increased yield might result from controlling the incidental catches of younger halibut. Ways and means of effecting such control should be explored.

scholarly journals Comparison of Inorganic Chlorine in the Southern Hemispheric lowermost stratosphere during Late Winter 2019

2021 ◽  
Author(s):  
Markus Jesswein ◽  
Heiko Bozem ◽  
Hans-Christoph Lachnitt ◽  
Peter Hoor ◽  
Thomas Wagenhäuser ◽  
...  
Keyword(s):  
Degradation Products ◽  
Polar Vortex ◽  
Boundary Region ◽  
Early Spring ◽  
Active Chlorine ◽  
The Arctic ◽  
Late Winter ◽  
Annual Variations ◽  
The Difference ◽  
The Antarctic

Abstract. Inorganic chlorine (Cly) is the sum of the degradation products of long-lived chlorinated source gases. These include the reservoir species (HCl and ClONO2) and active chlorine species (i.e. ClOx). The active chlorine species drive catalytic cycles that deplete ozone in the polar winter stratosphere. This work presents calculations of inorganic chlorine (Cly) derived from chlorinated source gas measurements on board the High Altitude and Long Range Research Aircraft (HALO) during the Southern hemisphere Transport, Dynamic and Chemistry (SouthTRAC) campaign in late winter and early spring 2019. Results are compared to Cly of the Northern Hemisphere derived from measurements of the POLSTRACC-GW-LCYCLE-SALSA (PGS) campaign in the Arctic winter of 2015/2016. A scaled correlation was used for PGS data, since not all source gases were measured. Cly from a scaled correlation was compared to directly determined Cly and agreed well. An air mass classification based on in situ N2O measurements allocates the measurements to the vortex, the vortex boundary region, and mid-latitudes. Although the Antarctic vortex was weakened in 2019 compared to previous years, Cly reached 1687 ± 20 ppt at 385 K, therefore up to around 50 % of total chlorine could be found in inorganic form inside the Antarctic vortex, whereas only 15 % of total chlorine could be found in inorganic form in the southern mid-latitudes. In contrast, only 40 % of total chlorine could be found in inorganic form in the Arctic vortex during PGS and roughly 20 % in the northern mid-latitudes. Differences inside the respective vortex reaches up to 565 ppt more Cly in the Antarctic vortex 2019 than in the Arctic vortex 2016 (at comparable distance to the local tropopause). As far as is known, this is the first comparison of inorganic chlorine within the respective polar vortex. Based on the results of these two campaigns, the difference of Cly inside the respective vortex is significant and larger than reported inter annual variations.

scholarly journals Effect size: commentary to the study on the Factors associated with the practice of exclusive breastfeeding

2020 ◽  
Author(s):  
Marisol Angulo-Ramos ◽  
César Merino-Soto
Keyword(s):  
Statistical Significance ◽  
Numerical Data ◽  
Practical Significance ◽  
Logistic Distribution ◽  
P Value ◽  
Knowledge And Skills ◽  
Instructional Content ◽  
The Difference ◽  
In Pregnancy

This letter focuses on recent and interesting work on breastfeeding, to emphasize two observations. The first observation refers to the fact that, in Mateus and Cabrera’s manuscript It was hardly discussed whether the referred knowledge and skills may be relevant to understanding the mothers’ behavior regarding their commitment to breastfeeding. The relevance of these cognitive aspects requires more attention due to their relationship with breastfeeding practices, and in general with the long-term mother-infant dyad. Because the knowledge and skills to maintain successful breastfeeding have implications for developing instructional content in interventions for mothers as well, great attention needs to be paid to the size of the effect of differences between reported frequencies in pregnancy and the immediate puerperium. In Table 3, these differences were examined by the McNemar statistical test, which allows obtaining the statistical significance of the rejection of the null hypothesis of no differences. But neither this test nor the size of its p-value inform about the degree or size of the differences. An estimate of the size or magnitude of the differences, represented as point values or confidence intervals (as reported in Tables 4 and 5), tend to better specify tests of statistical significance. Therefore, we estimate the practical significance of the difference between the percentages obtained in pregnancy and the immediate puerperium for each of the knowledge and basic skills reported in Table 3. With the only numerical data presented in this table, we calculated the McNemar odd ratio (McNemar OR , and standardized difference measures d: d Cox 8 and d probit . These show less bias with their population values in relation to other estimators5. Because they both assume different statistical assumptions e.g., logistic distribution for McNemar OR and d Cox , and normal distribution for d probit , calculating both will report the convergence or divergence of these estimates.

Stocking intensity and pastoral production: III. Wool production, fleece characteristics, and the utilization of nutrients for maintenance and wool growth by Merino sheep grazed at different stocking rates

1973 ◽  
Vol 81 (2) ◽  
pp. 211-218 ◽  
Author(s):  
J. P. Langlands ◽  
I. L. Bennett
Keyword(s):  
Live Weight ◽  
Early Spring ◽  
Metabolizable Energy ◽  
Late Winter ◽  
Stocking Rate ◽  
Wool Production ◽  
Digestible Organic Matter ◽  
Unit Increase ◽  
Rate Of Decline ◽  
Stocking Rates

SummaryWool production and wool characteristics are reported for a 5-year period in which sheep grazed Phalaris tuberosa–Trifolium repens pastures at stocking rates ranging from 2·5 to 37·1 sheep/ha. The utilization of nutrients for maintenance and wool production were calculated over shorter periods.Maximum wool production/ha was always recorded at the highest stocking rate attained. The highest annual maximum was 111 kg clean wool/ha in 1963–4. The decline in wool production/sheep/unit increase in stocking rate was greatest during winter and the amplitude of the seasonal rhythm in wool production increased with stocking rate.At high stocking rates wool count increased, staple length and character declined, colour and handle improved, soundness tended to decline and fibre entanglement (cotting) to increase particularly during drought. Live-weight gain/sheep also declined with stocking rate, the rate of decline being greatest during drought. Maximum live-weight change/ha was attained at a lower stocking rate than maximum wool production/ha.The maintenance requirement of grazing sheep was estimated to be 58·3 kcal metabolizable energy/day/kg live weight and did not vary consistently with stocking rate. The value was 79% greater than the requirements for penned sheep estimated from fasting heat production.Efficiency of wool production was defined as wool grown/100 g digestible organic matter intake (ED) and as wool grown/100 g nitrogen intake (EN). EN declined linearly with increasing stocking rate but the intercepts differed between months, and were least in late winter and early spring. En declined with stocking rate in winter and increased during summer. At low stocking rates, ED showed some variation throughout the year but this was much greater at high stocking rates.

scholarly journals Evolution of the stratospheric polar vortex edge intensity and duration in the Southern hemisphere over the 1979–2020 period

2021 ◽  
Author(s):  
Audrey Lecouffe ◽  
Sophie Godin-Beekmann ◽  
Andrea Pazmiño ◽  
Alain Hauchecorne
Keyword(s):  
Solar Cycle ◽  
Southern Hemisphere ◽  
Southern Oscillation ◽  
Polar Vortex ◽  
Onset Date ◽  
Late Winter ◽  
Stratospheric Polar Vortex ◽  
The Difference ◽  
Lower Variability

Abstract. The intensity and position of the Southern Hemisphere stratospheric polar vortex edge is evaluated as a function of equivalent latitude over the 1979–2020 period on three isentropic levels (475 K, 550 K and 675 K) from ECMWF ERA-Interim reanalysis. The study also includes an analysis of the onset and breakup dates of the polar vortex, which are determined from wind thresholds (e.g. 15.2 m.s−1, 20 m.s−1and 25 m.s−1) along the vortex edge. The vortex edge is stronger in late winter, over September–October – November with the period of strongest intensity occurring later at the lowermost level. A lower variability of the edge position is observed during the same period. Long-term increase of the vortex edge intensity and break-up date is observed over the 1979–1999 period, linked to the increase of the ozone hole. Long-term decrease of the vortex onset date related to the 25 m.s−1wind threshold is also observed at 475 K during this period. The solar cycle and to a lower extent the quasi-biennal oscillation (QBO) and El Niño Southern Oscillation (ENSO) modulate the inter-annual evolution of the strength of the vortex edge and the vortex breakup dates. Stronger vortex edge and longer vortex duration is observed in solar minimum (minSC) years, with the QBO and ENSO further modulating the solar cycle influence, especially at 475 K and 550 K: during West QBO (wQBO) phases, the difference between vortex edge intensity for minSC and maxSC years is smaller than during East QBO (eQBO) phases. The polar vortex edge is stronger and lasts longer for maxSC/wQBO years than for maxSC/eQBO years. ENSO has a weaker impact but the vortex edge is somewhat stronger during cold ENSO phases for both minSC and maxSC years.

Long-distance movments of juvenile brushtail possums (Trichosurus vulpecula) on farmland, Hawkes Bay, New Zealand

1996 ◽  
Vol 23 (2) ◽  
pp. 237 ◽  
Author(s):  
PE Cowan ◽  
RE Brockie ◽  
GD Ward ◽  
MG Efford
Keyword(s):  
New Zealand ◽  
Early Spring ◽  
Late Winter ◽  
Trichosurus Vulpecula ◽  
Radio Tracking ◽  
Juvenile Male ◽  
Long Distance ◽  
Male And Female ◽  
The Difference ◽  
One Year

Long-distance movements of juvenile male and female brushtail possums (Trichosurus vulpecula) at a farmland site, Hawke's Bay, New Zealand, were studied by radio-tracking. About 20% of radio-tagged possums dispersed more than 2 km, moving up to 11.5 km from their natal area, most in a north-easterly direction. The proportion of males that dispersed was higher than that of females, but the difference was not statistically significant. All juveniles dispersing did so before they were one year old. The bimodal timing of dispersal in summer and late winter to early spring reflected an underlying similar pattern of breeding. Most possums made several moves before settling. A higher proportion of possums dispersed from the lowdensity area of pastoral and cropping land than from the higher-density areas of swamp and willows. A few dispersal records of ear-tagged animals were also obtained; most records were of males from the area of pastoral and cropping land, and movements ranged from 3 to 25 km.

Long-term changes in the frost-free season on the Canadian prairies

2004 ◽  
Vol 84 (4) ◽  
pp. 1085-1091 ◽  
Author(s):  
Herb Cutforth ◽  
EG (Ted) O’Brien ◽  
Jason Tuchelt ◽  
Rick Rickwood
Keyword(s):  
Climate Change ◽  
Early Spring ◽  
Late Winter ◽  
Past Century ◽  
Canadian Prairies ◽  
Spring Frost ◽  
Growing Seasons ◽  
Spring Frosts ◽  
Agricultural Regions

The climate of the prairies has warmed over the past century, especially during late winter and early spring. Some regions of the prairies have warmed faster than others. Climate change has been documented to affect living systems in North America, such as promoting earlier phenological development and longer growing seasons. We examined weather records gathered at several long-term weather-recording sites across the agricultural regions of the Canadian prairies for evidence of trends in last spring frosts, first fall frosts, and frost-free durations. During the latter half of the 20th century, the trends were towards earlier last spring frost dates and towards longer frost-free seasons in the agricultural regions of the Canadian prairies. Across most of the prairies the trends towards later first fall frost dates were smaller and generally not significant. The largest changes have occurred in the central and northern agricultural regions of Alberta, whereas the least change occurred over much of southern Alberta and in southern Manitoba. Key words: Last spring and first fall frost dates, frost-free season, agroclimatic indices, climate change, Canadian prairies

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