Performance of crossbred progeny of Trangie Fertility Merino and Booroola Merino rams and Poll Dorset ewes. 1. Lamb birth weight, survival and growth

1995 ◽  
Vol 35 (8) ◽  
pp. 1069 ◽  
Author(s):  
DG Hall ◽  
NM Fogarty ◽  
AR Gilmour

Merino rams of the Trangie Fertility and Booroola strains were joined to Poll Dorset ewes in single sire mating groups over 3 years. Forty sires produced a total of 1250 lambs in 885 litters from 451 ewes. Lamb birth weight averaged 4.1 kg, 80.8% of lambs survived to 3 days of age and growth rates to weaning (mean 93 days) averaged 289 g/day. Lambs with Trangie Fertility sires grew 15 g/day faster and were 1.3 kg heavier at weaning than those lambs with Booroola sires (P<0.001). There were no effects of sire strain on birth weight or lamb survival. Birth weight increased with dam liveweight in mid-pregnancy (P<0.001), and weaning weight and growth rate increased with dam liveweight at joining (P<0.001). Survival of lambs was predominantly a function of birth weight. Lambs weighing 4 kg at birth from primiparous dams had survival rates of 76% compared with 88% for lambs from multiparous dams (P<0.01). No lamb under 2.0 or over 6.3 kg survived, and 48% of deaths occurred within 1 day of birth. Dystocia, particularly of heavy, single-born lambs, caused 53% of observed lamb deaths. For the traits birth weight, lamb survival, weaning weight and growth rate, the direct heritabilities were 0.24 � 0.10, 0.05 � 0.05, 0.19 � 0.10 and 0.12 � 0.08 respectively; the corresponding maternal heritabilities were 0.08 � 0.05, 0.05 � 0.04, 0.05 � 0.05 and 0.07 � 0.05 respectively; and the common environmental effects among litter mates (c2) were 0.57 � 0.08, 0.47 � 0.08, 0.15 � 0.08 and 0.13 � 0.08 respectively.

2004 ◽  
Vol 34 ◽  
pp. 57-66 ◽  
Author(s):  
A. Yilmaz ◽  
M. Ozcan ◽  
B. Ekiz ◽  
A. Ceyhan ◽  
A. Altine

SummaryThis study was carried out to investigate the fertility, milk production and body weight of ewes and the survival and growth characteristics of lambs of the indigenous Imroz and Kivircik sheep breeds. The Imroz and Kivircik sheep breeds are included among the genetic resources in the project for the conservation of the indigenous breeds in Turkey.Conception rates for Imroz and Kivircik ewes were 57.6% and 81.7% respectively, litter sizes were 1.2 and 1.2 respectively, milk yields were 89 kg and 62 kg respectively and average live weights (2–7 years of age) were 43 kg and 55 kg, respectively. Imroz and Kivircik lambs had survival rates at weaning (90th day) of 98% and 96%, birth weights of 3.3 kg and 4.1 kg and weaning weights of 19.8 kg and 28.0 kg, respectively.The results showed that the Kivircik sheep were heavier and the lambs had a better growth rate until weaning than the Imroz breed. However, the milk production of the Imroz ewes was higher than that of Kivircik. The lambs of both breeds had a satisfactory survival and growth rates until weaning and these results might be regarded as a desired adaptation of the Imroz and Kivircik lambs to the environmental conditions of the Marmara Region.


1974 ◽  
Vol 14 (69) ◽  
pp. 434 ◽  
Author(s):  
PA Kenney ◽  
IF Davis

A study of the survival and growth of lambs was made over a three year period (1968 to 1970) on a flock of 540 ewes grazing annual pasture at Werribee, Victoria. Ewes were stocked at three rates (5, 7 1/2 and 10 ha-1) and lambed between July 6 and August 20 or between September 10 and October 29 each year. Observations were made on the same ewes each year. Rate of stocking had no effect on the birth weight of lambs but single-birth lambs born in September were lighter than those born in July. More twins were born in September than in July and a smaller proportion of lambs born survived from the September than from the July lambing. Of the lambs born to ewes stocked at 10 ha-1 in 1968 and 1969 a smaller proportion survived than of the lambs born to ewes stocked at 5 ha-1. The growth rate of lambs born in July was constant between birth and weaning at 12 weeks of age but declined as rates of stocking increased. When the lambs born in September were about eight weeks old the pastures matured and growth rates of lambs declined and at weaning liveweights of lambs from plots stocked at different rates were similar. Lambs born in July on plots stocked at 5 and 79 ewes ha-1 were as much as eight kilograms heavier at weaning than the lambs born in September at equivalent rates of stocking. Neither rate nor time of onset of milk production was significantly affected by stocking rate.


1975 ◽  
Vol 26 (2) ◽  
pp. 393 ◽  
Author(s):  
GW Seifert

From random-bred populations of Africander cross (AX) and Brahman cross (BX), bulls and cows were selected within breeds for high and low weight per day of age (W/A) at c. 2 years of age and mated assortatively. There was a similar and significant response to selection in both breeds in birth weight and pre-weaning W/A as well as in pre-weaning gains. Although the BX animals were heavier and gained more than the AX animals, the differences were not as great or as consistent as the effect of selection. Calf gains were inversely related to cow gains from birth to weaning, but positively correlated to cow weight. During the pre-weaning period high W/A line cows gained significantly more than the low W/A line cows, while AX animals gained more than the BX group. The higher gain of the high W/A line cows and the higher weaning weight of their calves showed that these lines were more efficient than the low lines in terms of production of weaning weight. Very early calf gains from birth in November to January, and W/A in January, appeared to be poor indicators of the genetic potential of the calf and of the permanent environmental effects affecting its growth. In contrast, the period from January to March, during which the most rapid gains were experienced, reflected both the genetic potential and permanent environmental effects. The previous lactational status of the dam only affected birth weight and day of birth significantly and affected the AX calves more than the BX calves. This resulted in a significant interaction between breed and previous lactational status for these two traits.


1983 ◽  
Vol 37 (1) ◽  
pp. 25-31 ◽  
Author(s):  
N. Walker

ABSTRACTNinety-two gilts in replicates of four littermates were mated at puberty at a mean live weight and age of 95 kg and 191 days respectively. The littermates were allocated at random to one of four food allowances (kg/day) during four successive gestations: (A) 1·5, (B) 2·0 in parity 1 followed by 1·5 in subsequent parities, (C) 20 and (D) 2·5. A diet calculated to contain 12·7 MJ digestible energy per kg was fed throughout gestation, the 2-week lactation and from weaning to conception.The numbers of sows which conceived at parity 5 when the experiment terminated were 10, 12, 13 and 16 for treatments A to D respectively. Sow live weight at conception differed significantly (P < 0·01) from parity 2 onwards: the maximum live weights of sows on treatments A and B did not exceed 130 to 135 kg, but the live weights of sows on treatment D continued to increase to reach 195 kg at the end of the experiment. The in vivo skin plus subcutaneous fat thickness at the P2 location differed significantly (P < 0·001) between treatments from parity 2 onwards, decreasing by 3 mm in treatment A and increasing by 6 mm in treatment D from the start of the experiment to conception at parity 4. The interval from weaning to conception was significantly (P < 0·05) lower in treatment B in parity 2. This was the only significant effect and was contrary to the tendency for the interval to increase as the food allowance in gestation was decreased. The numbers of pigs born alive, stillborn or weaned (including fostered pigs) were not significantly affected by treatment. Birth weight and post-natal growth rates were significantly (P < 0·05) increased after parity 1 as gestation food allowance increased, with the exception of the post-natal growth rate in parity 3. Overall birth weight was increased by 018 kg per pig and weaning weight by 0·93 kg per pig on treatment D compared with treatment A.


1977 ◽  
Vol 17 (89) ◽  
pp. 909
Author(s):  
JK Egan ◽  
RL Thompson ◽  
JS McIntyre

In an experiment at Hamilton in western Victoria, groups of 30 Merino ewes were stocked at 11.7, 15.4 or 19.2 ewes ha-1 and joined to Merino rams each year on April 5 or May 8 for five weeks. Hay was conserved on half the number of plots and fed back to the ewes before and during joining. Observations on birth weight, survival, and growth of lambs born between 1970-73 are presented. Both the highest stocking rate and the earlier lambing were associated with a depression of about 7 per cent in the birth weight of twin lambs, but single lambs had similar birth weights on all treatments. Lamb survival was highly variable and there were few significant treatment effects. However, mortalities within 48 hours of birth were lower amongst flocks joined to lamb in October than those lambing in September (single lambs 9.2 per cent vs. 14.7 per cent-twin lambs 19.9 per cent vs. 40.2 per cent). Most of the improvement was attributed to drier conditions and lower windspeeds in October. Lamb growth rates fell with increasing stocking rate but the variation in weaning weight was less than 2 kg. Lambs born in September were about 10 per cent heavier at weaning than those born in October. Compensatory growth after weaning resulted in negligible differences in weight at 12 months between lambs from the different stocking rate treatments, but lambs born in September were still significantly heavier than those born in October.


2012 ◽  
Vol 9 (3) ◽  
pp. 1253-1265 ◽  
Author(s):  
P. Sabatier ◽  
J.-L. Reyss ◽  
J. M. Hall-Spencer ◽  
C. Colin ◽  
N. Frank ◽  
...  

Abstract. Here we show the use of the 210Pb-226Ra excess method to determine the growth rate of two corals from the world's largest known cold-water coral reef, Røst Reef, north of the Arctic circle off Norway. Colonies of each of the two species that build the reef, Lophelia pertusa and Madrepora oculata, were collected alive at 350 m depth using a submersible. Pb and Ra isotopes were measured along the major growth axis of both specimens using low level alpha and gamma spectrometry and trace element compositions were studied. 210Pb and 226Ra differ in the way they are incorporated into coral skeletons. Hence, to assess growth rates, we considered the exponential decrease of initially incorporated 210Pb, as well as the increase in 210Pb from the decay of 226Ra and contamination with 210Pb associated with Mn-Fe coatings that we were unable to remove completely from the oldest parts of the skeletons. 226Ra activity was similar in both coral species, so, assuming constant uptake of 210Pb through time, we used the 210Pb-226Ra chronology to calculate growth rates. The 45.5 cm long branch of M. oculata was 31 yr with an average linear growth rate of 14.4 ± 1.1 mm yr−1 (2.6 polyps per year). Despite cleaning, a correction for Mn-Fe oxide contamination was required for the oldest part of the colony; this correction corroborated our radiocarbon date of 40 yr and a mean growth rate of 2 polyps yr−1. This rate is similar to the one obtained in aquarium experiments under optimal growth conditions. For the 80 cm-long L. pertusa colony, metal-oxide contamination remained in both the middle and basal part of the coral skeleton despite cleaning, inhibiting similar age and growth rate estimates. The youngest part of the colony was free of metal oxides and this 15 cm section had an estimated a growth rate of 8 mm yr−1, with high uncertainty (~1 polyp every two to three years). We are less certain of this 210Pb growth rate estimate which is within the lowermost ranges of previous growth rate estimates. We show that 210Pb-226Ra dating can be successfully applied to determine the age and growth rate of framework-forming cold-water corals if Mn-Fe oxide deposits can be removed. Where metal oxides can be removed, large M. oculata and L. pertusa skeletons provide archives for studies of intermediate water masses with an up to annual time resolution and spanning over many decades.


1988 ◽  
Vol 111 (2) ◽  
pp. 363-368 ◽  
Author(s):  
F. Ruvuna ◽  
T. C. Cartwright ◽  
H. Blackburn ◽  
M. Okeyo ◽  
S. Chema

SummaryData on gestation period of 701 indigenous East African and Galla does and pre- and postweaning growth of 810 pure-bred and cross-bred kids were analysed by least squares statistical analysis. Breeds of kids were East African, Galla, Toggenburg × East African, Toggenburg × Galla, Anglo-Nubian × East African and Anglo-Nubian × Galla. Average gestation length was 149 days and was significantly (P < 0·05) affected by type of birth of the kid, year–month of kidding, and age of dam. Does carrying twins had shorter gestation length than does carrying singles. Sex and breed of kid did not have significant effect on gestation length.Significant (P < 0·05) factors affecting birth weight, weight at 30, 60, 90, 120, 150, 210 and 270 days of age, and preweaning growth rate were breed and sex of kid, type of birth, year–month and age of dam. Male kids grew faster and were heavier than females. Kids born single were heavier and grew faster than twin-born kids. Kids from dams less than 3 years old weighed less than kids from older dams. Cross-bred kids had higher preweaning growth rates than indigenous pure-bred kids. The Anglo-Nubian × Galla cross was heaviest while the East African ranked lowest. The results point to importance of cross-breeding with temperate breeds to increase growth rates of indigenous goats. Comparison of Toggenburg and Anglo-Nubian sires for cross-breeding showed both buck breeds produced kids with roughly equal growth rates. Evaluation of indigenous Galla and East African dams for cross-breeding showed Galla dams produced heavier kids than East African but preweaning growth rates were not significantly different.


PeerJ ◽  
2015 ◽  
Vol 3 ◽  
pp. e1392
Author(s):  
Juan C. Levesque

Ladyfish (Elopssp) are a common and economically valuable coastal nearshore species found along coastal beaches, bays, and estuaries of the southeastern United States, and subtropical and tropical regions worldwide. Previously, ladyfish were a substantial bycatch in Florida’s commercial fisheries, but changes in regulations significantly reduced commercial landings. Today, ladyfish are still taken in commercial fisheries in Florida, but many are also taken by recreational anglers. Life-history information and research interest in ladyfish is almost non-existent, especially information on age and growth. Thus, the overarching purpose of this study was to expand our understanding of ladyfish age and growth characteristics. The specific objectives were to describe, for the first time, age, growth, and recruitment patterns of juvenile ladyfish from the east coast of Florida (USA). In the Indian River Lagoon (IRL), annual monthly length-frequency distributions were confounded because a few small individuals recruited throughout the year; monthly length-frequency data generally demonstrated a cyclical pattern. The smallest were collected in September and the largest in May. Post-hoc analysis showed no significant difference in length between August and May, or among the other months. In Volusia County (VC), annual monthly length-frequency distribution demonstrated growth generally occurred from late-winter and spring to summer. The smallest ladyfish were collected in February and the largest in August. On average, the absolute growth rate in the IRL was 36.3 mm in 60 days or 0.605 mm day−1. Cohort-specific daily growth rates, elevations, and coincidentals were similar among sampling years. Cohort-specific growth rates ranged from 1.807 in 1993 to 1.811 mm day−1in 1994. Overall, growth was best (i.e., goodness of fit) described by exponential regression. On average, the absolute growth rate in VC was 28 mm in 150 days or 0.1866 mm day−1. Cohort-specific daily growth rates were significantly different among sampling years; however, the elevations and coincidentals were similar. Cohort-specific growth rates ranged from 1.741 in 1994 to 1.933 mm day−1in 1993. Mean ladyfish growth was best described by linear regression; however, natural growth was explained better by exponential regression. In the IRL, the corrected exponential growth equation yielded a size-at-age 1 of 156.0 mm SL, which corresponded to an estimated growth rate of 0.4356 mm day−1. In VC, the corrected exponential growth equation yielded a size-at-age 1 of 80 mm SL corresponding to an estimated growth rate of 0.2361 mm day−1.


2008 ◽  
Vol 48 (7) ◽  
pp. 974 ◽  
Author(s):  
J. E. Hocking Edwards ◽  
R. M. Gould ◽  
K. J. Copping

Merino weaner survival is poor under normal traditional management practices. Data from four trials conducted between 2001 and 2005 were used to assess the effectiveness of current industry recommendations to achieve 95% survival rates of Merino weaners. There was very little difference between 2001 and 2003 in survival of Merino weaners despite average weaning weight ranging from 20 to 24 kg between years. The recommended target weaning weight of 23 kg does not always appear to be a good predictor of survival. However, a target of 45% mature liveweight at pasture senescence achieved the industry recommendation of 95% weaner survival. Merino weaners were fed over the summer–autumn period to reach 40 kg liveweight by the time green feed became available. Weaner survival reached 93% compared with 89% survival to hogget shearing in weaners managed under normal growth paths. Furthermore, twice as many ewe weaners died in the traditional feeding program compared with the well fed ewe weaners. Differences in mortality between feeding levels in the wether weaners was less than that observed in the ewe weaners. Flock average growth rates were not useful indicators of weaner survival and there was no relationship between Merino ram estimated breeding values for weaning weight and the survival of the progeny.


Author(s):  
J A Milne ◽  
Angela M Sibbald

A desirable liveweight for red deer at 15 months of age is approximately 80 kg. This will provide a saleable carcase and a liveweight at which yearling hinds will successfully breed. Live-weight at 15 months will be influenced by a large number of factors including date of birth, birth-weight, liveweight gain to weaning, date of weaning, liveweight gain during the first winter and subsequent summer, and the interactions between weaning weight and subsequent levels of nutrition and between winter levels of nutrition and liveweight gain at pasture in the following summer. These latter two aspects were examined in two experiments and the effect of date of weaning on contemporary calf growth rates and on hind calving date in the following year were studied in a third experiment. The objective was to provide information which would allow the development of effective systems of deer meat production based on slaughter at 15 months of age.


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