Studies on the breeding season of Icelandic ewes and ewe lambs

1978 ◽  
Vol 90 (2) ◽  
pp. 275-281 ◽  
Author(s):  
Ø. R. Dýrmundsson
Keyword(s):  
Breeding Season ◽  
Individual Variation ◽  
First Year ◽  
Cyclic Activity ◽  
Breeding Activity ◽  
Ewe Lambs ◽  
The Mean ◽  
Considerable Individual Variation ◽  
A Minor ◽  
First Year Of Life

SummaryThe paper reports on a study, conducted in four successive seasons, of sexual development and breeding activity in females of the Iceland breed, the only breed of sheep kept in the country. The ewe lambs normally attained puberty in their first year of life, on average at 7 months of age, with marked individual variation in both age and body weight at first oestrus. Ewe lambs always showed oestrus on average slightly later than mature ewes (2–9 years), the mean date of onset of the breeding season of the latter being 8 December, however, with considerable individual variation. Furthermore, ewe lambs had a shorter breeding season (1–4 months) than ewes (4–6 months) and they appeared to experience more silent heats resulting in less regular cyclic activity. There seemed to be a minor increase in the duration of the oestrous cycle with age and ewe lambs clearly exhibited shorter oestrus (heat) than ewes. With seasonal breeding activity ranging from November to May the mid-breeding season occurs some 4–7 weeks after the shortest day.

Attainment of puberty and reproductive performance in Clun Forest ewe lambs

1972 ◽  
Vol 78 (1) ◽  
pp. 39-45 ◽  
Author(s):  
Ó. R. Dýrmundsson ◽  
J. L. Lees
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Breeding Season ◽  
Reproductive Performance ◽  
First Year ◽  
Cyclic Activity ◽  
Breeding Activity ◽  
Ewe Lambs ◽  
Wide Range ◽  
The Mean

SUMMARYCertain aspects of puberal development and reproductive performance in Clun Forest ewe lambs with a wide range of birth dates were investigated during the two seasons 1969–71. Of 33 ewe lambs born in the spring of 1969, 26 exhibited their first oestrus at a mean date of 8 November 1969 ± 2·5 days, the mean age being 228·3 ± 2·4 days and the mean body weight 36·3 ± 0·9 kg. The lambs which failed to breed in their first year, together with lambs born in the autumn of 1969, attained puberty during the autumn of 1970. Twenty-three ewe lambs carried foetuses to term in the spring of 1970 and had a mean lambing rate of 113·0 ± 7%. Of 84 ewe lambs born in the spring of 1970, 73 attained puberty in the first year of life at a mean date of 11 November 1970 ± 2·7 days, the mean age being 223·7 ± 3·0 days and the mean body weight 32·2 ± 0·5 kg. Cyclic activity of ewe lambs born in 1970 was recorded throughout their first breeding season. They experienced their last oestrus of the season at a mean date of 24 January 1971 ± 2·2 days, the mean age being 296·9 ±3·9 days and the mean body weight 32·4 ± 0·6 kg. The mid-breeding season was 18 December 1970, coinciding with the shortest days, and the mean number of heats exhibited throughout the season was 5·15 ± 0·24 per lamb.Marked individual variation existed in age and body weight at puberty and in breeding activity, largely due to differences in date of birth and growth rate during rearing. Ewe lambs born early tended to experience their first oestrus earlier in the season than late born lambs but they did so at a higher age and heavier body weight. Fast growth rate and earliness of puberty were associated with extended duration and enhanced regularity of cyclic activity. Time of birth was clearly of fundamental importance in relation to the onset and duration of breeding activity in the ewe lambs included in the present study.Adult rams of three breeds were found to vary consistently in the proportion of ewe lambs which they detected in oestrus, rams of the lambs' own breed being most efficient.

Effect of autumn shearing on breeding activity in Clun Forest ewe lambs

1972 ◽  
Vol 79 (3) ◽  
pp. 431-433 ◽  
Author(s):  
Ó. R. Dýrmundsson ◽  
J. L. Lees
Keyword(s):  
Body Weight ◽  
Field Conditions ◽  
First Year ◽  
Cyclic Activity ◽  
Natural Field ◽  
Group Iii ◽  
Breeding Activity ◽  
Ewe Lambs ◽  
Stage Of Development ◽  
The Mean

SUMMARYSeventy-two Clun Forest ewe lambs were randomly stratified into three groups (I, II and III) of 24 each according to date of birth and body weight at 6 October 1970. The ewe lambs of Groups I and II were shorn on 15 and 30 October, respectively, and Group III acted as unshorn control. The ewe lambs were reared under natural field conditions but supplementary feeding and shelter were provided during the winter months.A large proportion (94%) of the ewe lambs attained puberty in their first year and differences between the three groups in the number of ewe lambs reaching this stage of development were small and not significant. Autumn shearing of ewe lambs was associated with a very slight but statistically wholly insignificant delay in the mean date of puberty whereas the duration of cyclic activity in these lambs was not affected by such treatments.

Variations in the time of onset of the breeding season in Clun ewes

1966 ◽  
Vol 67 (2) ◽  
pp. 173-179 ◽  
Author(s):  
J. L. Lees
Keyword(s):  
Ambient Temperature ◽  
Breeding Season ◽  
Cyclic Activity ◽  
Breeding Activity ◽  
The Mean ◽  
Limited Period

Variations in the time of onset of the breeding season in Clun ewes have been studied during the four years 1962-65. Differences within seasons were studied in 1963 and 1964 by scattering the lambing over the first 7 months of the year. The date of first service then appears to be very highly dependent on the date of previous lambing. Time of previous weaning appears to be less important.Very highly significant differences have been found between seasonal means and these differences have been shown to be significantly related to the mean ambient temperature during a limited period between mid-summer and the mean date for the resumption of cyclic activity in the ewes. The higher this temperature the later the onset of breeding activity. Over the years individual ewes have tended to breed consistently either early or late.

Disaccharidase Deficiency

1985 ◽  
Vol 7 (3) ◽  
pp. 67-75
Author(s):  
Martin H. Ulshen
Keyword(s):  
Small Intestine ◽  
Minor Component ◽  
Building Blocks ◽  
Cow Milk ◽  
Milk Formula ◽  
First Year ◽  
Caloric Content ◽  
Dietary Component ◽  
A Minor ◽  
First Year Of Life

Disaccharidases are enzymes of the small intestine, and they are essential for normal carbohydrate digestion. Carbohydrates are an important dietary component, providing about half of the calories in a typical Western diet. The smallest carbohydrate units, the monosaccharides, are the building blocks for more complex sugars and starches. The monosaccharides of dietary importance include glucose, galactose, and fructose. Carbohydrates are present in an average diet, primarily in the form of dissacharides (two monosaccharides linked together) and starches (glucose polymers). The disaccharide lactose is the major carbohydrate in milk and accounts for about 40% of the caloric content of human milk as well as commercial cow milk formula. Lactose is composed of the monosaccharides glucose and galactose; sucrose is composed of glucose and fructose. During the first year of life, juices and solids are introduced into the diet in increasing amounts and, therefore, sucrose and starches provide an increasing proportion of the dietary calories. By the adult years, about 50% of dietary carbohydrate is ingested in the form of starch, and lactose is often a minor component of the diet. Among the dietary carbohydrates, only the monosaccharides can be transported intact across the luminal surface of the small intestine. The moroe complex carbohydrates must undergo digestion prior to assimilation.

Sudden Infant Death Syndrome in a Twin: A Comparison of Sibling Histories

PEDIATRICS ◽  
1986 ◽  
Vol 78 (1) ◽  
pp. 146-150
Author(s):  
A. Kahn ◽  
D. Blum ◽  
M. F. Muller ◽  
L. Montauk ◽  
A. Bochner ◽  
...  
Keyword(s):  
Sudden Infant Death Syndrome ◽  
Infant Death ◽  
Sudden Infant Death ◽  
Clinical Risk Factor ◽  
Control Group ◽  
Sudden Infant ◽  
First Year ◽  
Control Infant ◽  
The Mean ◽  
First Year Of Life

To determine possible characteristics of infant victims of sudden death, we examined 114 items related to the pre- and postnatal histories of 42 pairs of twins one of whom died of sudden infant death syndrome (SIDS) leaving a surviving sibling. Interviews with the parents were conducted after the occurrence of SIDS, and the data were checked with records held by gynecologists and pediatricians. To evaluate the specificity of any factors, we studied a control group of 42 age- and sex-matched pairs of twins, both of whom survived the first year of life. Only 11 of 114 characteristics were significantly related to SIDS: future victims had a smaller weight and height at birth, stayed longer in the nursery, and followed a moving object with their eyes, had head control, and smiled at a later age than their surviving siblings. They also fatigued more often during feeding (11/42) and had reduced arm and neck tonus (9/42). They were described as longer sleepers than their surviving siblings. During sleep, some SIDS twins, but no surviving twin, were found to be cyanotic at least once or pale (4/42) and were repeatedly covered with abundant sweat (8/42). In the control group of normal twins, the occurrence of most of these characteristics was found with a frequency comparable to that seen in the SIDS infants; the specificity of these characteristics is thus considered doubtful. The mean birth weight and height were significantly greater in the control group, and no control infant had an episode of cyanosis or pallor or repeated episodes of profuse sweating observed during their sleep. It is concluded that, if further research validates the occurrence of night hyperhydrosis in some future SIDS victims, this symptom could be a clinical risk factor.

Development of Blue-Yellow and Red-Green Discriminations in Infants during the First Year of Life

Perception ◽  
1997 ◽  
Vol 26 (1_suppl) ◽  
pp. 235-235
Author(s):  
L I Leushina ◽  
V M Bondarko ◽  
A A Nevskaya
Keyword(s):  
Healthy Subjects ◽  
Risk Group ◽  
Emotional Reaction ◽  
Mean Difference ◽  
The Other ◽  
First Year ◽  
Colour Discrimination ◽  
The Subject ◽  
The Mean ◽  
First Year Of Life

Colour discrimination was investigated in infants aged 4 – 14 months. 250 healthy subjects and 80 subjects with slight defects in basic visual functions (the risk group) participated. A coloured toy was moved in front of the subject and disappeared behind a screen, reappearing after 2 – 3 s at the other side. Sometimes when the toy was hidden, the experimenter replaced it with another one that differed only in colour: yellow was replaced by blue or vice versa (Y/B switch), or red by green or vice versa (R/G switch). The form and size of the toy remained constant. The emotional reaction of surprise showed whether the infant discriminated these colour pairs. The brightness of the stimuli was slightly varied make sure that the infant reacted to the change in colour rather than brightness. About 75% of healthy 4 – 5-month-olds showed good expressive reactions to the Y/B switch, and practically all children did so at 7 – 8 months. The discrimination of red and green develops more slowly: only at 12 months did practically all children show good reactions to the R/G switch. In all children, Y/B discrimination preceded R/G discrimination. The mean difference between the numbers of children discriminating these two pairs was 7.6%. The infants of the risk group were as good as their healthy age-mates in Y/B discrimination, but performed significantly less well on R/G: the mean difference between the numbers discriminating the former but not the latter was 17.0%. Possible reasons for the retardation of chromatic discrimination in the risk group are discussed.

scholarly journals Early Introduction of Sugar-Sweetened Beverages and Caries Trajectories from Age 12 to 48 Months

2020 ◽  
Vol 99 (8) ◽  
pp. 898-906 ◽  
Author(s):  
E. Bernabé ◽  
H. Ballantyne ◽  
C. Longbottom ◽  
N.B. Pitts
Keyword(s):  
Dental Caries ◽  
Young Children ◽  
Later Life ◽  
Rate Of Change ◽  
First Year ◽  
Sugar Sweetened Beverages ◽  
Sweetened Beverages ◽  
The Mean ◽  
First Year Of Life ◽  
Over Time

Early exposure to sweet tastes predicts similar food preferences and eating behavior in later life and is associated with childhood obesity. The aim of this study was to explore the associations of early (during the first year of life) and subsequent intake of sugar-sweetened beverages (SSBs) with 4-y caries trajectories among Scottish young children. We used data from 1,111 Scottish children who were followed annually from age 12 to 48 mo (4 sweeps in total). SSB intake was reported by parents in every sweep. SSB intake was broken down into 2 components, the initial SSB intake and the deviation over time from that initial value. Childhood dental caries was clinically determined (including noncavitated and cavitated lesions) every year. The association of SSB intake with baseline decayed, missing, and filled tooth surfaces (dmfs) (intercept) and rate of change in dmfs over time (slope) was examined in 2-level linear mixed-effects models, with repeated observations nested within children. Both the initial SSB intake and the deviation from the initial SSB intake were positively associated with steeper caries trajectories. By sweep 4, the predicted mean dmfs difference was 1.73 between children with low and high initial SSB intake (1 standard deviation below and above the mean) and 1.17 between children with low and high deviation from their initial SSB intake (1 SD below and above the mean). The findings of this prospective study among Scottish young children provide evidence that the introduction of SSBs during the first year of life can put children in a trajectory of high levels of dental caries. They support current recommendations to avoid sugars for very young children and interventions targeting early feeding practices for caries prevention.

Effect of body weight on the attainment of puberty and reproductive performance of Galway and Fingalway female lambs

1979 ◽  
Vol 28 (3) ◽  
pp. 297-307 ◽  
Author(s):  
J. F. Quirke
Keyword(s):  
Body Weight ◽  
Breeding Season ◽  
Litter Size ◽  
Conception Rate ◽  
Restricted Feeding ◽  
Ewe Lambs ◽  
Younger Age ◽  
Body Weights ◽  
The Mean ◽  
Ad Libitum

ABSTRACTGroups of spring-born Galway (G) and Fingalway (F) ewe lambs were fed a concentrate diet either ad libitum (H) or at a restricted level (L) during the period 25 July to 16 October 1974 in order to induce differences in body weight at the start of the breeding season. The mean live weights of the GL, GH, FL and FH groups on 16 October 1974 were 37·8 ± 1·3, 44·6 ± 1·3, 35·1 ± 1·1 and 41·9 ± 1·2 kg respectively. More than 95% of the lambs in all four groups attained puberty before 28 February 1975. Galway ewe lambs reached puberty later in the breeding season and were older and heavier at puberty than Fingalways. Animals fed ad libitum were heavier at puberty and attained puberty earlier in the season and at a younger age than those on the restricted feeding regime.Both conception rate and litter size were lower in Galways than Fingalways. There was no evidence of any effect of the nutritional treatments on conception rate or litter size. The mean body weights at puberty for ewes which lambed and those which were barren were 41·9 ± 0·49 and 41·5 ± 0·78 kg respectively. The birth weight and growth rate of the progeny of the ewe lambs was similar for the two breeds and was not influenced by the previous nutritional treatment of the dams. The total lamb mortality between birth and weaning was 40·3%, and 72% of all deaths occurred within 48 h of birth. Losses among twins (48%) were particularly heavy.

scholarly journals Vitamin D Deficiency in Children Despite Correctly Applied Rickets Prophylaxis

2020 ◽  
Vol 70 (12) ◽  
pp. 4332-4335
Keyword(s):  
Vitamin D ◽  
Vitamin D Deficiency ◽  
Calcium Absorption ◽  
Pediatric Population ◽  
Clinical Signs ◽  
Serum Levels ◽  
First Year ◽  
Vitamin D Levels ◽  
The Mean ◽  
First Year Of Life

Vitamin D is essential for calcium absorption and for maintaining bone health in the pediatric population. We conducted a retrospective study to establish the profile of a child aged under 3 years old with vitamin D deficiency in the context of correct prophylaxis, on a cohort of 49 children from two general practitioner offices. From the study group 30.6% of children (15 cases) had low vitamin D levels. The mean serum 25(OH)D level was 41.5±16.6 ng/ml. Regarding nutrition in the first year of life, breastfeeding predominated (83.7% of patients), and only 8.16% of patients had clinical signs of rickets. So, low serum levels of vitamin D can also be found in children who have successfully received correct prophylaxis with vitamin D. Keywords: vitamin D, children, rickets

Variability in the drinking behaviour of individual emus Dromaius novaehollandiae

2016 ◽  
Vol 38 (5) ◽  
pp. 489
Author(s):  
S. J. J. F. Davies ◽  
T. A. Knight
Keyword(s):  
Western Australia ◽  
Individual Variation ◽  
Maximum Temperature ◽  
Drinking Behaviour ◽  
Time And Space ◽  
Water Influx ◽  
Dromaius Novaehollandiae ◽  
Mean Size ◽  
The Mean ◽  
Considerable Individual Variation

The drinking behaviour of four captive emus Dromaius novaehollandiae Latham 1790 was examined at the CSIRO Laboratory, Helena Valley, Western Australia. Considerable individual variation was found in the amount of water each emu drank daily, but for each bird the amount drunk was positively correlated with daily ambient maximum temperature. There was also considerable variation between individual birds in the number of sips of water taken daily, in the mean size of each sip and in the distribution of the size of sips taken in each drinking bout. Variability in drinking behaviour has been reported in other species of bird when their water influx has been calculated using double-labelled water. The availability of water to emus varies greatly in both time and space. More thirsty emus may do well when water is plentiful, whereas more abstemious ones may be favoured when water is scarce. Hence, variability in drinking behaviour would be maintained in populations.

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