Estimation of heterosis in Merino × Corriedale crosses with sheep

1971 ◽  
Vol 22 (3) ◽  
pp. 521 ◽  
Author(s):  
LG Iwan ◽  
BC Jeffries ◽  
HN Turner

Reproduction rate data (lambs born, lamb survival rate, and lamb body weight) are presented for purebred Merino and Corriedale ewes and their reciprocal crosses. The four breeds were born in each of two years (1961 and 1962) and mated in each of two years (1963 and 1964, 1964 and 1966) to Dorset Horn rams. Heterosis was estimated as the superiority of the mean of the crossbreds over the mean of the purebreds, expressed as a percentage of the latter. The heterotic effect for lambs born per ewe joined was 1.9 % in 2-year-old ewes and 5.3 % in adults, the corresponding figures for lamb survival being 3.5 and 1.4 % for single-born, 17.2 and 12.0% for twin-born lambs. For mean age-corrected lamb body weight, 2-year-old ewes showed a heterotic effect of 3.7 % and adult ewes 2.0 %, while for pounds of lamb weaned per ewe joined the figures were 11.3 and 10.2%. Although some heterosis was exhibited, the mean of the crossbreds seldom exceeded that of the superior parent (the Corriedale), and there were sometimes differences between the reciprocal crosses, the Corriedale x Merino cross being superior in performance to the other. The potential for exploiting this degree of heterosis in reproduction rate cannot be assessed until the corresponding wool data have been analysed. In reproduction rate, the Corriedale was superior to the Merino, but again a final conclusion about their merits must await results on wool data.

1965 ◽  
Vol 45 (1) ◽  
pp. 33-36
Author(s):  
G. W. Rahnefeld

The relationship between thickness of fat measured at the shoulder, last rib, and loin of live pigs and market weight (86.2 to 95.2 kg) was studied in 1596 pigs from the Lacombe and Yorkshire breeds and their reciprocal crosses. No significant breed or sex differences were found in the proportion of fat at the three sites. Breed and sex differences were evident in the average depth of fat. The regression coefficients for the mean of three fat measurements on market weight were.016 ±.003,.019 ±.007, and.017 ±.004 for Lacombe males, barrows, and females respectively;.039 ±.002,.036 ±.005, and.041 ±.001 for Yorkshire males, barrows and females respectively;.027 ±.005 and.029 ±.004 for barrows and females from the Lacombe male × Yorkshire female mating; and.023 ±.007 and.021 ±.009 for barrows and females from the Yorkshire male × Lacombe female mating. Comparisons between animals measured at a relatively constant weight should be made after the fat measurement is adjusted for variations in body weight. The results of this study indicate that separate corrections should be applied for each breed. Separate corrections for sexes within breeds do not appear warranted.


1960 ◽  
Vol 11 (1) ◽  
pp. 75 ◽  
Author(s):  
M Wodzicka

The monthly wool growth of three groups of rams was studied at Beltsville, Maryland. Group I received natural daylight (at 38° 53' N.) and was shorn monthly. Group II had a 7:17 hours of daylight to hours of darkness rhythm and was shorn every 6 months, once in winter and once in summer. Group III received natural daylight and was likewise shorn every 6 months. The rams of all groups produced more wool in summer than in winter. This difference was significant (P<0.001). The mean body weight and food intake were both greater in the winter months, which indicated that the seasonal rhythm of wool growth was not a consequence of poorer feeding in winter. The rams which were shorn monthly (group I) grew considerably more wool than the other two groups, but the difference was not statistically significant. The short-day treatment of group II did not increase the annual wool production nor decrease the seasonal rhythm of wool growth. The balance of evidence from this and other experiments indicates that temperature rather than light controls the seasonal rhythm of wool growth.


1959 ◽  
Vol 1 (1) ◽  
pp. 85-91 ◽  
Author(s):  
A. F. Purser ◽  
G. B. Young

The effects of birth weight, maternal age and parity on survival of single lambs have been studied in a Blackface and a Welsh Mountain flock.In both flocks the maximum survival rate was found to occur among lambs with birth weights just above the mean. Mortality increased as lambs' birth weight increased or decreased from the optimum, but was especially heavy at the lower extreme of the range of birth weights.Mortality decreased with age of dam to 14·3% for lambs from 4- to 6-year-old Blackface ewes and to 9·4% for lambs of 3- to 4-year-old Welsh ewes. Ewes having their first lambs gave mortality rates twice as great as for the mature ewes in the same flocks. The lower chances of survival of first born lambs irrespective of dam's age accounts for the apparent trend of mortality with maternal age in the Blackface.Changes in mortality rates associated with variation in lamb's birth weight and with the age structure of the ewe flock were estimated. Possible means of improvement of survival rate are discussed.


Agriculture ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 412 ◽  
Author(s):  
Mariusz Jerzy Stolarski ◽  
Michał Krzyżaniak ◽  
Dariusz Załuski ◽  
Józef Tworkowski ◽  
Stefan Szczukowski

Perennial crops harvested in short rotations provide substantial amounts of biomass. This study determined the survival rate, biometric features and yield of fresh and dry biomass of 15 willow genotypes (including seven varieties and eight clones), cultivated at two different sites in two consecutive three-year harvest rotations. The study revealed the very high impact of the genotype (81% of the total variance) on the willow yield. The harvest rotation, along with the genotype, had a significant impact on the plant survival rate and the number of shoots per stool. Willow biomass was mainly affected by the plant height, its survival rate and shoot diameter. The significantly highest fresh (106 Mg ha−1) and dry biomass yield (54.0 Mg ha−1) was obtained from the Żubr variety of S. viminalis, which distinguished this variety from the other genotypes. The mean yield for the best three and five genotypes was 13% and 17% lower, respectively, and the mean yield for the whole experiment was 37% lower compared to the mean yield of the best variety (Żubr). Therefore, the choice of a willow genotype is of key importance for successful willow production.


1967 ◽  
Vol 7 (24) ◽  
pp. 7 ◽  
Author(s):  
P McInnes ◽  
TJ Grainger ◽  
MD Smith

Data are presented on the recovery and reproductive performance of 2 1/2-year-old maiden Merino ewes after a prolonged period of undernutrition. The 217 sheep had been hand-fed on a submaintenance ration in pen feeding trials at Glenfield, New South Wales. During the seven months of the trials they had lost 6 kg (28 to 22 kg) body weight. They were transported to Condobolin in south-western New South Wales, divided into two treatment groups and run on good quality pastures. One group was joined immediately (May 1959) and again ten months later, and the other group was mated after six months at Condobolin (in October 1959) and again 12 months later. The ewes recovered rapidly. The mean weight of both groups had reached 30 kg within six weeks and 40 kg within six months. In the first year 73 of the 100 May-mated ewes bore lambs, but only 38 of these lambs were weaned. Ewes bearing lambs had a higher body weight at the start of joining and gained more during joining than the barren ewes. At the other three joinings (October 1959, May 1960, October 1960) lambing percentage was from 86-89 and weaning percentage from 62-69-both normal for the district. The proportion of twin lambs (3-6 per cent) was low. Wool weight in 1959 was not affected by time of mating or by pregnancy.


2014 ◽  
Vol 66 (2) ◽  
pp. 510-518 ◽  
Author(s):  
L.P. Souza ◽  
H.C.C. Fries ◽  
G. Heim ◽  
J.E. Faccin ◽  
L.F. Hernig ◽  
...  

The aim of the study was to evaluate the behaviour, pre-weaning survival rate and growth performance of low birth weight (BW) piglets cross-fostered with piglets of higher weights. Piglets were transferred to 60 foster sows, and divided in three groups (G; n=20): G1- 12 low BW piglets (0.80 - 1.25kg); G2- six low BW piglets and six intermediate BW piglets (1.40 - 1.60kg), and G3- six low BW piglets and six high BW piglets (>1.70kg). For the analysis, groups G2 and G3 were subdivided in LG2 (six G2 light piglets); IG2 (six G2 intermediate piglets), LG3 (six G3 light piglets), and HG3 (six G3 heavy piglets). Behavioural observations were carried out on days 1, 2, 4 and 6 (visual direct observation) and on days 3 and 5 (video recording) after birth. The percentage of missed nursings was higher in LG3 piglets than in LG1, IG2 and HG3 piglets, on days 1 and 2. On day 4, light piglets (LG1, LG2 and LG3) missed more nursings than IG2 and HG3 piglets. On day 3, video recording showed a higher percentage of missed nursings in LG1, LG2, and LG3 piglets as compared to HG3 piglets. On day 1, the number of fights during nursing was higher in IG2 than in LG1 and LG3 piglets. Also on day 1, number of fights and percentage of piglets engaged in fights, during 15min after nursing, were higher in LG1, LG3 and HG3 than in LG2 piglets. More playful behaviours were observed on day 2 in IG2 and HG3 piglets compared to LG1, LG2 and LG3 piglets. Light piglets (LG1, LG2, and LG3) presented similar body weight on days 4, 8, 12 and 16 after birth, regardless of being mixed with piglets of higher weights or not; however, the survival rate until day 16 was most compromised in LG3 piglets compared to the other groups. Despite the lack of influence of littermates' weight on the growth of low BW piglets, their survival rate indicates that they should not be mixed with high BW piglets.


Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 5437-5437
Author(s):  
Jian Ouyang ◽  
Longdian Chen ◽  
Bing Chen ◽  
Jingyan Xu ◽  
Cuiping Li ◽  
...  

Abstract Nowadays it is widely used as glucocorticoids, ortho-oxybenzoic acid, immunosuppressive agents and biological agents for Crohn’s Disease. But all these agents can only control the symptoms rather than curing the diseases. About 70% patients need surgery in the course. 5 patents of Crohn’s Diseases have received AHSCT in our department since 2004. These patients, including 3 male and 2 female, with a mean age of 32 (range, 23~46), were final confirmed by enteroscope and histology. The mean CDAI of these patients was 213 points (range, 170~256), and the mean interval between invasion and transplantation was 63 months (range, 27~132 months). All the patients had mild or severe diarrhea and abdominal pain, one of them have a 6cm×7cm lump touchable in the abdominal region, while one of them complicated with vesicorectal fistula. These patients were mainly treated with glucocorticoids, SASP, cyclophosphamide (CTX), et al, which didn’t control the condition. Mobilization program was CTX 2g/m2 for 2 days and G-CSF 5~10 μg/kg/d on the 5th day of medication. Leukapheresis was initiated when WBC>5.0×109/L. The collections of CD34+ cells from two cases were over 4×106/kg, and ClinMACs cell separation system was used to purify the CD34+ cells and to deplete T cells. Two collections of CD34+ cells were 1.3×106/kg and 2.8×106/kg, respectively, and then were kept in −80°. And the other case failed in the collection, and then was treated with bone marrow transplantation. The conditioning programs were MC (CTX 60mg/kg -2, -1d;melphalan 140mg/m2 -2d) for one case, and CTX 50mg/kg×4d for the other 4 cases. 2 of the 3 patients without in vitro purification of CD34+ cells to deplete T cells were treated with rabbit antithymocyte globulin 5 mg/kg on day-2 and day -1 for T cell depletion. The mean CD34+ cells infused was 1.4×106/kg(range, 1.3×106/kg~2.8×106/kg). Neutrophile granulocyteand>0.5×109/L occurred at day +10~+12, while platelet>2.0×109/L occurred at day +9~+11. Fever occurred in all patients in the granulocytopenia phase, and lasted from 1 to 3 weeks. One of the patients complicated with ESBL+ ichoremia, and was cured with antibiotics. After the transplantation, 2 patients were treated with prednisone 10mg/d as maintenance therapy, and the other 3 stopped using antidiarrheal and glucocorticoids. 4 patients got free of abdominal pain and diarrhea in the following 2~3 months, and the other did in 1 year. The average body weight of the patients increased 11.2 kg (range, 3~20kg) 3 months after transplantation. The mean follow-up was 16 months. 2 patients have been maintaining remission until now. The lump in the abdomen of one of these 2 patient decreased from 6×7cm to 5×5cm, which was resected 19 months after transplantation. And this patient is still in remission now. 3 patients relapsed after 4~8 months of remission. One of them relapsed 5months after transplantation and died complicated with peritonitis in 7 months. One patient relapsed in 8 months with abdominal discomfort, mild diarrhea, and decreasing of body weight. The other complicated with rectovesical fistula showed closure of syrinx by barium enema, and suffered abdominal discomfort, mild diarrhea, and decreasing of body weight too 4 months after transplantation, then relapsed with rectovesical fistula 8 months after transplantation. HSCT for Crohn’s disease is safe and effective. However, it has a comparative higher relapse rate.


1969 ◽  
Vol 20 (3) ◽  
pp. 549 ◽  
Author(s):  
Haas HJ De ◽  
AA Dunlop

Reproductive records covering 4855 ewe-years coming from five strains of Merino ewe run at three locations over 5 years were classified into those which resulted in (a) failure to lamb, (b) a single birth, or (c) a multiple birth. Age of ewe was included as a further classification, while pre-mating body weight was considered as a covariate. The data were analysed by least squares procedures. In all analyses in which components of variance were estimated, error variance constituted more than 90% of the total. Of the main effects, those due to age were generally largest, particularly where they related to the proportion of dry ewes and multiple births, though year effects on the proportion of dry ewes ranged up to 0.10. The effects of pre-mating body weight on lambing performance were small though real, the largest being an increase of 0.37% of multiple births per pound increase in body weight. First order interactions were generally small, the most prominent being location x strain, location x age, and location x year. The third of these had the largest effects and accounted for more of the variance. This was particularly so in the proportions of dry ewes and single births. Location x age interactions, on the other hand, were more prominent in affecting the proportion of multiple births, where the increase with age was much less marked at one location than at the other two. Strain x location interactions were not large enough to suggest any marked adaptation of strains to particular locations in these mutually dependent traits.


1963 ◽  
Vol 14 (6) ◽  
pp. 882 ◽  
Author(s):  
NM Tulloh

A comparative growth study was made of Hereford, Aberdeen Angus, and beef Shorthorn cattle reared and kept together throughout their lives on irrigated perennial pastures at the Metropolitan Farm, Werribee, Vic. Records of body weight as a function of age were obtained on 404 Hereford, 172 Aberdeen Angus, and 127 Shorthorn cattle, representing cattle born in 1955, 1957, 1958, 1959, and 1960. At birth, male calves were significantly heavier than females, and Hereford calves were significantly heavier than Shorthorn and Aberdeen Angus calves, the birth weights of Shorthorn and Aberdeen Angus calves being similar. Up to the age of 5 years, the younger and lighter 2-year-old cows produced lighter calves than cows which were both older and heavier. At weaning age (9.5 months) steers were significantly heavier than heifers. Herefords were significantly heavier than Aberdeen Angus in two years out of three; and in one year out of three, Herefords were significantly heavier than Shorthorns. Shorthorns were significantly heavier than Aberdeen Angus in one year out of three. When the steers were finally weighed off grass at the mean age of either 20 months (1958, 1959, and 1960 cattle) or 25 months (1957 cattle), Herefords were significantly heavier than Aberdeen Angus in four successive years, and in one year out of four the Herefords were significantly heavier than Shorthorns. In three years out of four, Shorthorns were significantly heavier than Aberdeen Angus. Breed differences between the mean weights of breeding cows were not significant and, up to the age of 5 years, as breeding cows grew older they became heavier. Body weight growth curves indicated that the cattle experienced a severe check in growth during the winter months (June, July, August). At other times of the year, growth rates were satisfactory. Cattle born in some years grew better than cattle born in others. This was thought to be due partly to differences between years in the quality and quantity of pasture available, even though the pastures were irrigated. Average absolute and average relative growth rates were calculated for the 1957 and 1958 steers before and after weaning. Breed differences in absolute growth rates before weaning were not statistically significant, but after weaning, rates were significantly the highest for Herefords in both years. The breed differences in average relative growth rates were in the same direction as those for absolute growth rates. However, the pre-weaning relative growth rate of Shorthorns was significantly higher than those of the other breeds among the 1957 steers. When due allowance was made for the smaller size of Aberdeen Angus steers at birth and at weaning, the relative growth rates of this breed were less than those of the other breeds. Absolute and relative growth rates were higher for all breeds before weaning than afterwards. This was mainly a reflexion of low post-weaning growth rates during the winter months. Rank correlation coefficients between birth weight and weight at subsequent ages were low and variable in different breeds and in different seasons. However, coefficients calculated between subsequent ages, beginning at weaning age, were generally highly significant. The breed and sex differences presented in this paper have been compared with the limited data from the literature and, in general, the results are similar.


1967 ◽  
Vol 7 (26) ◽  
pp. 206 ◽  
Author(s):  
MC Franklin ◽  
P McInnes ◽  
PK Briggs

Merino wethers of 30 months of age were hand-fed in pens on low-(chaffed wheaten straw), medium-(84 per cent chaffed wheaten straw; 16 per cent chopped lucerne hay), and high-protein roughage (chopped wheaten hay, or 67.5 per cent chaffed wheaten straw : 32.5 per cent chopped lucerne hay) alone, or supplemented with wheat grain at daily or twice-weekly intervals. The experimental period was 26 weeks and emphasis was placed on the number of survivors, changes in body weight, and mean daily roughage intake. Data were also collected on wool production. No sheep survived on the low-protein roughage (LPR-2.7 per cent crude protein (CP) ). Seven out of 16 sheep in the medium-protein roughage group (MPR-5.2 per cent CP) survived for 26 weeks ; six of these, however, died in the following four weeks. All sheep survived on the two high-protein roughage diets (HPR(1) and HPR(2)-7.6 per cent CP). The wheat supplement increased the number of survivors in the LPR and MPR groups. There was no difference between results from the daily and twice-weekly supplemented groups. Mean daily roughage intake of the unsupplemented sheep increased at each level of protein in the roughage. Mean intake of chaffed wheat straw when fed alone was 220 g per sheep per day. The intake of the same straw when fed with chopped lucerne hay increased by 120 g per sheep per day in the group fed MPR, and by 344 g in the group fed HPR(1). The wheat supplement did not increase intake within any roughage group. Roughage intake was significantly decreased on the HPR(2) diet when a wheat supplement was given. Sheep fed HPR(2) grew more clean wool than sheep in the other unsupplemented groups. Differences between mean clean wool weights of daily and twice-weekly supplemented groups within each roughage group were not significant, but differences between the mean pooled wool weights of each supplemented roughage group were significant.


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