Ewe Weight Research Articles

Influence of body condition and lasalocid during late gestation on blood metabolites, lamb birth weight and colostrum composition and production in Finn-cross ewes.

The objective of this experiment was to examine the effects of body condition (BC) and of lasalocid (L) the last 4 wk of gestation on blood metabolite profiles, lamb birth weight and colostrum composition and production. Twenty-eight 3-yr-old Finn-Targhee ewes (73 kg) were assigned randomly within BC grouping (2.5 or 3.5) and individually fed a diet of 90% alfalfa pellets and 10% of a supplement containing either no L (C = control) or L. Gestation and 24-h postlambing weights were higher (P less than .05) for 3.5 BC versus 2.5 BC ewes. Lasalocid had no effect (P greater than .05) on ewe weight. Average number of lambs born within treatment groups were similar (P greater than .05). Total kilograms of lamb born were greater (P less than .10) for 3.5 BC ewes. Body condition 3.5 ewes had greater concentrations of total protein (P less than .10) and albumin (P less than .05) the last 4 wk of gestation than those in the 2.5 BC group. Feeding L decreased (P less than .05) blood urea-N in comparison with C ewes. Colostrum composition and production were not influenced (P greater than .05) by BC, L or number of lambs born. Serum 3-hydroxybutyrate seemed to be a good indicator of energy metabolism; albumin and blood urea-N concentrations reflected dietary protein intake. Lasalocid had a minimal effect on nutrient metabolism and productivity of ewes fed in excess of the NRC (1985) protein and energy requirements.

Studies on reproduction in prolific ewes

SummaryIn Expt 1, 34 individually-penned Finn Dorset ewes of mean live weight 68 kg were synchronized in oestrus and mated to Suffolk rams. From mating until day 28 of pregnancy each received daily 15 MJ of metabolizable energy (ME) and 225 g crude protein (CP). From day 28 to slaughter on days 34, 41, 48 or 55 half of the ewes continued on this feeding regime and half had their daily intake reduced abruptly to 7·5 MJ of ME and 112 g CP. The mean number of ovulations per ewe was 4·03 (range 2–8) and the mean number of viable foetuses at time of slaughter 3·35 (range 2–6). The combined loss of ova (fertilization failure and early embryonic death) was 14·6% and detectable foetal deaths 2·2%. Level of feeding had no significant effect on these measures or on foetal growth. Foetal growth from 34 to 55 days was described by the equationIn w = 0·962–18·613 e-0·0272t–0·00091t(f–3),where w = foetal weight (kg), t = age (days) and f = litter size. Within-litter variability measured as the S.D. of In w (kg) was 0–081 for twins, 0·108 for triplets and 0·106 for quadruplets and higher multiples.In a second experiment Suffolk × Finn Dorset embryos were transplanted at the rate of two per uterine horn into 15 recipient Finn Dorset ewes. Embryo survival was 72% and foetal weights at 60 days varied from 67 to 146% of the mean value of 66 g. Withinlitter variation in foetal size was only about 70% of that expected for foetuses developing from the variable distribution in their initial positioning that occurs naturally. The correlation between foetal weight and placental weight at day 60 was 0·72 (P < 0001) indicating that the association between foetal weight and placental weight in prolific ewes is not confined to late pregnancy.The results of both experiments are consistent with the hypothesis that the greater within-litter variability in birth weight in large litters is controlled by events in early pregnancy.

Effect of prolonged intermittent water restriction on the reproductive performance of ewes in the Indian desert

ABSTRACTThe reproductive performance of female Magra and Marwari sheep of the desert areas of north-western India was studied in relation to intermittent water deprivation, for a period of 39 months during which four breedings were completed. The control group received an ad libitum supply of water every day, while the water-restricted group was provided with water on the same 2 days each week only throughout the experimental period, except during the monsoon season. All the ewes were maintained on cultivated Cenchrus ciliaris pasture. No ill effect was noticed on the general health of the animals. Reproductive measures such as incidence and duration of oestrus, length of the oestrous cycle, conception rate, lambing rate, length of gestation, post-partum interval, inter-lambing period, post-lambing weight of ewes and birth weight of lambs were not significantly affected by the imposed water deprivation. The dailywatered ewes had a slightly, but not significantly higher gain in body weight than the water-restricted ewes. It wa^ concluded that ewes of these two breeds could be maintained on a twice weekly watering schedule for prolonged periods of time without having any adverse effect on their reproductive performance.

Performance of different Scottish Blackface stocks and their crosses

SUMMARYThe performance of different stocks of Scottish Blackface sheep and their crosses was compared on a harsh Scottish hill experimental farm. The strains were the Stanhope farm stock (a control flock, closed for 30 years), stock from local Breeders, and first crosses and back-crosses of Stanhope stock with stocks represented by rams purchased at Lanark market. Some 3892 ewe records were available with 1837 lamb performance records. Estimated effects for the three types of stock and of heterosis in the Stanhope and Lanark cross were derived statistically. The local Breeders' stock had the heaviest lambs at weaning and the Stanhope stock the lightest. The local Breeders' stock also had the heaviest ewes and higher litter size but had lower fertility and lower lamb survival. Output expressed relative to ewe weight was highest for the cross-bred stock. Heterosis was positive for all traits studied except survival but was statistically significant only for ewe weight and lamb birth weight. If the Stanhope stock was representative of Scottish Blackface sheep of 30 years ago, breeding by Scottish Blackface breeders has led to an estimated improvement of 9% in the output per ewe exposed, and 5% in efficiency of production.

A note on the effect of nutrition during mid pregnancy on lamb production of primiparous ewes in high body condition at mating

Mid-Pregnancy nutrition has been shown to have both positive and negative effects on lamb birth weight in primiparous Scottish Blackface ewes. The direction of the effect depends on the level of body condition at mating, being negative in ewes in high body condition (Russel, Foot, White and Davies, 1981). In the same study, it was argued that the effect in younger ewes could be due to their greater sensitivity to both under- and over-nutrition during the earlier to mid stages of their first pregnancy than is evident in older ewes. Russel et al. (1981) also suggested that the level of mid-pregnancy nutrition is likely to have effects on other aspects of production such as embryonic loss, foetal mortality and even ewe mortality.

Factors affecting lamb birth weights from high fecundity Booroola ewes

The influence of year, weight of ewes at joining, litter size and wastage during pregnancy (ovulation rate minus litter size) on lamb birth weights was examined for three flocks of Booroola cross ewes with an average ovulation rate of 2.2 and litter size of 1.8. The largest proportion of variation in birth weight was associated with litter size (71– 83%) in all flocks, a smaller proportion (6.7–11.8%) with year differences and minor but significant proportions with ewe joining weight (0.9–4.4%) and wastage during pregnancy (1.1–3.5%). The effect of wastage during pregnancy was consistent across flocks and suggests that at high ovulation rates the increased probability of prenatal deaths is associated with a reduction in birth weights of lambs born in the resulting litters. In the flocks studied it is estimated that about 8% of lambs born had birth weights depressed by >0.3 kg due to pregnancy wastage.

Performance of lambs from three crossbred ewe types

ABSTRACTThe performance of predominantly Suffolk-sired lambs from Border Leicester (BL), Bluefaced Leicester (BFL) and ABRO Damline (DL) crossbred ewes was compared on 18 commercial and college farms throughout England and Wales. The comparison took place over the 5-year period 1977 to 1981 and was the second stage in a comparative study on the productivity of the crossbred ewes. A total of 1277 crossbred ewes were involved with data on up to 3 years lambings per ewe, giving a total of 3522 mating records and 4864 lamb records.The BFL lambs were heaviest and the DL lambs were lightest. The DL lambs had the lowest survival rates, and the BFL lambs the highest. The BFL lambs were slaughtered earlier (12 days) and at heavier weights (1·4 kg) than the DL and BL lambs, and had slightly heavier carcasses. The DL and BFL carcasses had better MLC carcass classifications than the BL, resulting in an advantage of 4 p/kg of carcass.In productivity per ewe, the BFL litters had the highest slaughter and carcass weights and the highest income per litter, with the DL litters intermediate. An attempt was made to express productivity per unit of sheep weight maintained, taking account of ewe weight, litter size and the lamb slaughter date. On this index, the DL were marginally superior to the BFL, and both were superior to the BL.

The effect of stocking rate on a lamb production system with February‐lambing ewes

AbstractMasham ewes were stocked at 12(L), 16(M) or 20 (H) ewes ha−1, with 1·8 lambs per ewe on average, on two blocks (A and B) in both 1976 and 1977. Silage was offered at pasture to the ewes in early lactation and as stocking rate increased from 12 to 16 and then 20 ewes ha−1, 47, 73 and 100 kg DM per ewe was consumed respectively. Silage was cut mainly in the autumn and 179, 100 and 9 kg per ewe was made for L, M and H respectively. More variation between treatments was measured in net herbage accumulation in summer than spring and 11·4, 10·0 and 9·7t DM ha −1 was grown over the whole season for L, M and H respectively as a mean of both years.High intakes of herbage OM were measured with values up to 40 g per kg live weight for BL lambs in 1976. Rapid lamb growth was achieved. There were effects of stocking rate on lamb performance and for L, M and H the respective growth rates to 4 weeks were 266, 248 and 247 g d−1; growth rates to sale were 274, 263 and 252 g d−1; days to sale were 124, 126 and 129; mean carcass weights were 17·7, 17·1 and 16·7 kg. Most ewes lost weight in early lactation, especially AH and BH in 1976, but there were no stocking rate effects on ewe weight change in 1977.

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

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.

Lactation performance, herbage intake and lamb growth of Scottish Blackface and East Friesland × Scottish Blackface ewes grazing hill or improved pasture

ABSTRACTScottish Blackface (BF) and East Friesland × Scottish Blackface (EFX) ewes rearing single or twin lambs grazed for 14 weeks of lactation on two different pasture types in two consecutive years. Mean daily milk production, live-weight change and herbage intake of the ewes and live-weight gain of the lambs were measured each week.In the first year the ewes grazed a ryegrass/clover sward. There were significant differences in milk production associated with breed of ewe and number of lambs reared. Peak yields, achieved in the 3rd or 4th week, reached 2·25, 2·5 and 3·25 kg/day for BF ewes with a single lamb and EFX ewes with single or twin lambs, respectively. Corresponding yields in the 14th week were 0·5, 1·35 and 1·15 kg/day. Live weight of ewes in all groups declined during the first 2 weeks but recovered by week 6. Herbage intake increased in all groups until the 8th week and then declined much more rapidly in the BF than in the EFX ewes. Lamb growth was related to milk intake to give weaning weights of 31·5, 39·0 and 29·0 kg, respectively.In the second year, when ewes grazed a hill pasture dominated by an AgrostislFestuca community, differences in milk production, though significant, were smaller than in the previous year. Peak yields were 2·1, 2·25, 2·25 and 3·1 kg/day, respectively, for BF ewes with single or twin lambs and EFX ewes with single or twin lambs. At 14 weeks, yields had fallen to between 0·6 and 1·0 kg/day. The patterns of live-weight change and food intake were similar to those in the previous year. The EFX ewes consumed more food than BF ewes throughout lactation, particularly in the second half. Lamb growth rate was again related to milk supply and was lower than in the previous year. Weaning weights were 31·0, 25·5, 34·5 and 27·0 kg for single or twin lambs reared by BF or EFX ewes, respectively.

The productivity of breeding ewes grazing on lucerne or grass and clover pastures on the tablelands of southern Australia. II. Wool production and ewe weight.

Spring-lambing Merino and crossbred ewes grazing on dryland lucerne pastures were generally heavier throughout the year than ewes grazing on phalaris and subterranean clover pastures, even though they experienced greater weight losses during winter. These losses were mostly eliminated by compensatory gains in spring. Annual fleece weights of the Merino ewes grazing on lucerne or phalaris and subterranean clover pastures declined linearly by 146 and 64 g respectively for each additional ewe carried over a range of stocking rates from 9 to 18 ha-1. Corresponding figures for crossbred ewes were 114 and 46 g. In each case the difference between pasture species was significant (P < 0.02). Only at the lowest stocking rates were fleeces from ewes on lucerne heavier (by c. 500 g) than those from ewes on phalaris. At the highest stocking rates, there were no advantages in terms of wool production from grazing breeding ewes on lucerne. Not only was there a greater need for supplementary feed during late pregnancy to avoid losses from pregnancy toxaemia, but the lucerne pastures at all stocking rates proved more sensitive to unfavourable physical and chemical characteristics of soils than did phalaris and subterranean clover pastures. The fleece weights of Merino and crossbred ewes declined, on average, by 70 and 50 g per year for ewes aged between 1+ and 6+ years. Pregnancy reduced fleece weights by 5-10% in Merinos and 5-21% in crossbred ewes, depending on seasonal conditions which varied from year to year. For Merinos only, dry ewes grew about 4% more wool than lactating ewes. No other effects of reproduction on fleece weights were observed.

Maternal performance of oxford and suffolk breeds, of sheep, and their crosses

ABSTRACTThe proportion of ewes lambing of those exposed to the ram, litter size and weight at lambing, and at weaning, pre-weaning lamb mortality and changes in ewe weight during suckling, were studied in 326 ewes (931 lambings) representing two pure breeds, Oxford and Suffolk, and four crossbreds, Oxford♂ × Suffolk♀, Suffolk♂ × Oxford♀, North Country Cheviot♂ × Oxford♀ and Cheviot♂ × Suffolk♀, mated to purebred and crossbred rams during 9 years. The proportional fertility in the Oxford and Suffolk ewes (0·82 and 0·85 respectively) was lower than that of Suffolk × Oxford (0·93), Oxford × Suffolk (0·94), Cheviot × Oxford (0·88) and Cheviot × Suffolk (0·88) ewes. Litter sizes of Suffolk ewes at birth and at weaning were 1·6 and 1·3 lambs, 0·3 (0·22) and 0·3 (0·27) lambs largeir than those of the Oxford ewes, respectively. The corresponding figures for litter weight were 1·29 kg (0·22) and 11·8 kg (0·36). Oxford ewes lost 0·10 of their weight during nursing compared with 0·14 for the Suffolk and the two reciprocal crosses. The estimates of heterosis in litter size and litter weight at birth were 0·085 and 0·082, and at weaning were 0·13 and 0·18 respectively.The results showed that Oxford crosses were better in performance than the pure Oxford, whereas the Suffolk crosses were similar in performance to the pure Suffolk, except in the proportion of ewes lambing of those exposed and pre-weaning mortality, in which the crosses were 0·07 and 0·20 superior to the pure Suffolk, respectively.Breed of sire had a significant effect on litter weight at birth and at weaning, whereas the interaction breed of sire × breed of dam was a significant source of variation on litter size and litter weight at birth and at weaning. Litter performance at birth was significantly lower in 2-year-old ewes and in ewes sired by 3-year-old or older rams than in other age groups

An analysis of the variation in the lean tissue distribution of sheep

ABSTRACTThe distribution of lean tissue between eight standard joints was examined in 956 crossbred lambs slaughtered at constant live weights of either 35 or 40 kg. The sire breeds used were the Dorset Down, Ile-de-France, Oldenburg, Oxford, Suffolk and Texel. Sire breed did not have a significant effect on the proportion of total carcass lean found in the higher-priced joints but did show significant differences in the proportion of total carcass lean found in individual joints, with a maximum difference of 7·7 g total lean per kg joint being recorded. Similarly, small but significant effects due to ewe age (1 to 3 years), rearing type (single, twin, triplet), sex (male castrate, female) and weight of total lean were reported for the proportion of total carcass lean found in different joints.Heritability estimates ranged from 0·07 (s.e. 008) to 0·65 (s.e. 0·16) for the proportion of total lean in the best-end neck and higher-priced joints respectively. Phenotypic standard deviations of 5·8g/kg and 17·9g/kg were reported for the proportion of total lean found in the best-end neck and the higher-priced joints respectively. The genetic correlations between the proportion of total lean in each of the higher-priced joints and the proportion of total lean in the higher-priced joints combined were positive. A genetic correlation of 017 (s.e. 0·20) was found for the relationship between average daily gain from birth to slaughter and the proportion of total lean in the higher-priced joints.

Apple Pomace and Urea for Gestating Ewes

Use of apple pomace (AP) supplemented with soybean meal (SBM) or a cornmeal-urea mixture (CU) for gestating ewes was studied in five trials with a total of 404 gestating ewes. Trial 1 (42 ewes) compared wet AP supplemented with SBM or CU. Ewe weight gain and lambing performance were poorer for ewes fed AP-CU than for ewes fed AP-SBM, and intakes of both diets were low. Trial 2 (40 ewes) compared dehydrated AP supplemented with SBM or CU fed to ewes bedded with straw or unbedded. Gain and lambing performance were poorer for ewes fed AP-CU than for ewes fed AP-SBM, particularly for unbedded ewes. Dehydrating AP did not improve intake; thus, gain and performance for both SBM and CU treatments were poor. Intakes were generally lower for unbedded ewes than for bedded ewes. Trial 3 (112 ewes) compared a control diet to AP diets supplemented with SBM, CU, isolated soy protein (IS), CU plus additional IS, or CU plus straw fed to ewes bedded with straw or unbedded. The lower intakes for unbedded ewes and the poorer ewe weight gains and lambing performance for ewes fed AP-CU than for ewes fed AP-SBM were repeated in this trial. Among the AP diets, intake of the AP-CU-straw diet was greatest, and this diet diminished the adverse effects of AP-CU on lambing performance. Additional IS tended to improve ewe gains and fetal growth. Trials 4 and 5 (210 ewes) compared various combinations of a control diet and supplemented AP. Data were also obtained with dehydrated poultry excreta (DPE) as the N supplement for AP and with dehydrated citrus pulp (CP) instead of AP as the major dietary ingredient. Intakes, gain, and lambing performance were normal when 50% or less of the diet dry matter was from supplemented AP; results with SBM, CU, and DPE supplements were similar. The feeding of diets containing only supplemental CP reduced intake and performance similar to results of ewes fed only supplemented AP.

TUJ YAPAĞILARI'NIN BAZI FİZİKİ ÖZELLİKLERİ ÜZERİNDE BİR ARAŞTIRMA

OZET Cildir'zn Dogruyo! koyu, y'oresilide yetistirilen Tujlarm yapagilari parlak beyaz renkte olup hali tipi yapagi ozellikleri gosterirler. lik kirkimlari yapilan disi ve ikiz esleri olmayan Tuj/arda yapagi gomlek agir. lik ortalamasi 1,210 kg. dir. Bu miktar, ayni yas ve dnsiyetteki Morkaramanlarinkinden fazladir. YapagJlardd randiman ortalamasi :ya 83,41 olup, bu deger yerli irklaruntza ait degerlerden ustundur. Ayrica, Tu) yapagi/arinda bitkisel madde yok denilecek kadar azdir. Yapagi liile uzimluklari, hali ipligi yapinuna uygilt! uzunlukta bulundular. Yapagi/arda, kil incelik ortalamasi 34, 60 mikron olup ve 70.00 mikrondan kqba olan killarin nisbeti :ya 5 dir. Ki/ incelik dagilimina gore, Tu) yapagi/arimn :ya 21 i' kumas yapimma uygun durumdadir. SUMMARY This reserarch was caried out in order to determino some physical PJoperties of wool obtained from Tuj sheep raised in the district of 'Dogruyol willage. 50 head yearling ewes were seJected randomly among some flocks raised in that region. ' . The wool saqi.ples used in this study were taken from the rib area of the sheep i during the shearing time. According to the result; the average fleece weight of Tuj ewe is i ,210 kg. and wool yield is 3,41 ~~. Staple length is 6,72 cm. and dianieter of fiber is 34,60 mikr,ons. , As a ,~onclusion it has been seen that, T~j, sheep hav~ produced less wool clip as an avrage than other unjmpro~ed sheep bre~ds. in addition to the selectian will be practiced,' in order to obtaine'. more neece' weight Tuj rams having more , fleece weight and longer staple legnth should be ~ated to Tiij ewes. We beliye that, these problems wiU be solved in the next generations.

Summer Grazing of Sagebrush-Grass Range by Sheep

Summer Grazing of Sagebrush-Grass Range by Sheep

The effect of weight at mating and of nutrition during mid-pregnancy on the birth weight of lambs from primiparous ewes

SUMMARYForty-eight approximately 18-month-old Scottish Blackface ewes were used to study the effects of two levels of nutrition during mid-pregnancy (30–98 days of gestation) on the birth weight of lambs from ewes varying in weight, size and condition at first mating. The mean live weight (42–4 kg), size index (31–9) and condition score (2–4) at mating of the 26 ewes from flock A were all less than those of the 22 ewes from flock B (54–5, 39–4 and 2–9 respectively). Mean intakes of the low and high nutritional treatment ewes during mid-pregnancy were 10–6 and 22–0 g/kg/day respectively of a pelleted diet supplying 8–81 MJ metabolizable energy and 125–5 g crude protein/kg. These intakes produced estimated changes in net maternal weight of approximately – 5 and 0 kg respectively.Mean lamb birth weights from ewes on the low and high nutritional treatments were:flock A, 3–32 and 3–83 kg; flock B, 4–96 and 4–23 kg respectively. Analyses showed intake during mid-pregnancy to have a positive effect on lamb birth weight in the flock A ewes, and a negative effect in flock B ewes. Mating weight accounted for 78% of the variance in birth weight in the low nutritional treatment ewes but had little effect in those on the higher level of feeding.The practical implications of the results are discussed in relation to levels of juvenile nutrition.

Milk production from subtropical non-dairy sheep. 1. Ewe performance

SummaryMilk yield of 270 Rahmani, Ossimi and Barki subtropical Egyptian ewes rearing single lambs during three successive lambings in 2 years was estimated over 12 weeks of the lactation using a lamb-suckling technique. The ewes received either normal or high level of feeding during late pregnancy and lactation.Ossimi and Rahmani ewes showed significantly (P < 0·01) higher total milk production than the Barki. Milk yield declined sharply for the Barki ewes after the 6th week of lactation. Breed variation failed to attain statistical significance in the first 4 weeks of lactation. The highly fed ewes produced significantly (P < 0·01) more milk at different stages of lactation than the normally fed ones. High level of feeding, however, is not recommended for subtropical non-dairy ewes as it is not economic. Spring-lambing ewes produced significantly more milk during the first 8 weeks of lactation, while the summer-lambing ewes were more persistent in their milk yield in the last 4 weeks of lactation.Neither age of ewe nor body weight significantly affected milk yield. Correlation coefficients between milk yield and body weight at lambing are small and range from 0·00 to 0·24.

Productivity of purebred and crossbred finnsheep. II. Lamb weights and production indices of ewes.

Birth and weaning weights were studied for purebred Finnsheep, Suffolk, Targhee and Minnesota 100; F1 Finnsheep crosses; F2: and standard breed and Finnsheep backcrosses. Finnsheep lambs were the smallest of all lambs at birth, but ranked second among purebreds in 70-day weaning weight (Suffolks, 21.0 kg vs Finnsheep, 17.6 kg). Ewe body weight, grease fleece production and total adjusted weight of weaned lamb were compared among purebreds and crossbreds. The Finnsheep was the smallest pure breed, yielded the lightest fleeces, but produced the heaviest total weight of weaned lamb. The F1 ewes were all heavier and produced more wool than the midparent mean of their respective breeds. They also produced markedly more weaned lamb than did the parental standard breeds. Body weight, wool and lamb production were all lower in the F2 than in the F1 groups. Ewe index was calculated as the total adjusted (male, 70-day equivalent) weight of weaned lamb plus three times the grease fleece weight. The ranking of purebreds was Finnsheep, Targhee, Suffolk and Minnesota 100. Average ewe index values for F1 ewes were greater than those for respective parental and standard breeds. F2 and standard breed backcross ewes had lower index values than did F1 or Finnsheep backcross ewes. Ewe index per unit of ewe body weight was also evaluated. Finnsheep ranked highest, followed by the 3/4 Finnsheep. The Targhee was the best of the standard breeds for this index.

Some observations on high- and low-potassium Chokla sheep given water intermittently under semi-arid conditions

SUMMARYNon-breeding groups, I, II and III, each with six high-potassium (HK) and six lowpotassium(LK) Chokla ewes were given water once in 24, 48 and 72 h respectively. In the next summer, seven ewes (4 HK and 3 LK) from each group I, II and III were switched over to a watering schedule of once in 24, 72 and 96 h respectively and were naturally bred. All the animals were maintained on grazing alone.Water deprivation for 72 h caused 18·8 and 19·2% body weight loss in HK and LKewes respectively; an overall average maintenance of weight loss in LK ewes was significantly higher than in HK ewes from the same group. There were significant differences in water intake due to treatments only. The HK and LK ewes from groups I and III showed a similar trend.Pregnant ewes of HK and LK types given water once in 96 h lost 21·7 and 23·8% of their body weights respectively. Corresponding weight loss in aborted ewes were 23·8 and 33·3%. Two ewes, each from 3 LK and 4 HK animals aborted owing to water deprivation for 96 h. The water intake reached 30 and 36·5% of body weight in LK and HK pregnant ewes given water intermittently.The wool attributes of non-pregnant ewes did not indicate a significant influence of blood potassium types. Four out of five ewes of the LK phenotype died during 3 years, irrespective of watering schedule.