We studied the effects of the frequently used glucogenic dietary supplementation in dairy herds and the hormonal changes occurring during the normal estrous cycle on the composition and concentration of milk lipid components. Holstein dairy cows were synchronized with two injections of prostaglandin F2α (estrus=day 0). Animals were held as controls or drenched for 11 days (day −3 to day 8 of the cycle) with 850 ml/day liquid propylene glycol (treatment, n=13 per group). Blood and milk samples were collected on day 1 and 8 of the cycle. In both groups, plasma progesterone concentration increased ∼10-fold between 1 and 8 days post-estrus. Milk fatty acid composition was associated primarily with estrous-cycle day: polyunsaturated fatty acids increased by 16%, n-6 by 15% and n-3 by 1% from day 1 to 8 post-estrus. Polar lipid composition was also altered by cycle day: phosphatidylethanolamine concentration was 2-fold and 1.5-fold higher on day 1 v. day 8 post-estrus in the control and treatment groups, respectively. Phosphatidylserine concentration in milk was also affected by cycle day by treatment interaction (P=0.04). A progesterone level by treatment interaction influenced the triglyceride-to-phospholipid ratio in the milk (P=0.02). The results suggest that progesterone plays a role in modulating milk lipid composition and structure. Therefore, strategies designed to alter milk lipid composition should consider the cow’s reproductive status.

Out-wintering beef cows reduces annual housing costs and bedding requirements and there is less exposure to diseases associated with housing. However, to counter these benefits cows may be exposed to conditions that pose a significant challenge to welfare, and ways of assessing this are required. Two feeding treatments were applied to four groups of 10 cows (two groups/treatment), one to maintain condition score (H) and the other to allow a modest loss of condition score (L), which is commonly applied in farm practice. Cow groups were rotated around four paddocks in a Latin Square design of four periods each of 3 weeks, and they were weighed and condition was scored at the end of each period. Their behaviour and location was recorded at 30-min intervals with six 3-h sessions in each period. Ambient temperature, wind speed, rainfall and solar radiation were recorded every 30 min to enable calculation of cow lower critical temperature (LCT). The climatic conditions were wet at the start of the experiment with moderate wind speeds throughout (5 m/s) and relatively mild ambient temperature (5°C). Feeding treatment had no significant effect on any of the variables measured. Cows spent most of the observation sessions standing, particularly at the beginning of the experiment when the soil conditions were wettest. They sought sheltered locations when wind speeds were high and thus their calculated LCT was near or below ambient temperature. Nutritional models predicted periods of cold stress but the cows adapted their behaviour to counteract this, emphasising the need for a combined physical and behavioural approach to assessing welfare challenges.

The influence of food allowance or level of food excess on diet selectivity and intake by sheep given pearl millet stover leaves, and the potential feeding value of the food leftovers (not eaten) (L) were studied. Animals were given food at four levels of L (100, 300, 500 and 700 g dry matter (DM) per day). All sheep received different food allowances (A, g DM per day) and had different L/A and A/M (g DM per kg M) ratios. An additional treatment consisted of feeding the leftovers from the two highest levels of food excess to six rams to have 300 g DM of L per day. A diet supplement was given to provide sufficient rumen degradable protein and sulphur to sustain microbial activity. Variances of organic matter (OM) digestibility (OMD, g/kg) and intake (g/kg M0·75) of both DM (DMI) and digestible OM (DOMI) of the original millet leaves were analysed using L, L/A, A/M and A/M0·75 as independent variables. Variation accounted for was highest when OMD was analysed as a function of L/A (R2 = 0·34) and when DMI was analysed as a function of A/M (R2 = 0·79) or A/M0·75 (R2 = 0·80). The response in OMD to varying L/A was best described by the equation OMD = 457 (s.e. 16) + 157 (s.e. 48) L/A. As L/A or A/M increased, L had a lower concentration of acid-detergent fibre and a higher in sacco OM disappearance. As A/M increased, DOMI and L/A increased following a diminishing return pattern. However, when A/M fell below 31·1 (s.e. 0·9) g DM per kg M, DOMI decreased linearly. No differences (P > 0·33) were observed for OMD between the original food (505 (s.e. 8) g/kg) and the re-fed leftovers (489 (s.e. 15) g/kg), but DOMI was lower with the latter (22•4 (s.e. 0·4) v. 20·3 (s.e. 0·8) g/kg M0˙75, P < 0·03). Results suggest that DOMI of millet stover should be determined at L/A much higher than the traditionally recommended (0·15), and support the hypothesis that farmers could benefit from feeding millet stover at high allowances to animals of high economic value and give the leftovers to less valuable or less selective stock.

A model is described, which maximizes hay intake in the formulation of rations for pregnant ewes in the last 6 weeks of pregnancy. A regression of hay intake upon hay digestibility, concentrate level, ewe live weight, number of foetuses carried and week of pregnancy, derived from an experiment on individually-recorded ewes, is used as the intake constraint in a linear programme. This is solved in an interactive program which can be implemented on several makes of microcomputer. The intakes of hay predicted by the model are lower than those reported elsewhere, reflecting the more accurately recorded intakes of the original experiment compared with most other published data. The rations formulated by the model show that in weeks 16 to 18 of pregnancy hay could provide most of the ewes' requirements and especially when hays of high metabolizable energy concentration are used. The ease of changing the values of the inputs and the speed of the ration formation enable any number of rations to be formulated quickly for a range of hays and individual conditions.

Piglet birth weight and litter uniformity are important for piglet survival. Insulin-stimulating sow diets before mating may improve subsequent piglet birth weights and litter uniformity, but the physiological mechanisms involved are not clear. This study evaluated effects of different levels of insulin-stimulating feed components (dextrose plus starch; fed twice daily) during the weaning-to-estrus interval (WEI) on plasma insulin and IGF-1 concentrations, and on follicle development and subsequent luteal, fetal and placental development and uniformity at days 42 to 43 of pregnancy. During WEI, multiparous sows were isocalorically fed diets supplemented with 375 g/day dextrose plus 375 g/day corn starch (INS-H), with 172 g/day dextrose plus 172 g/day corn starch and 144 g/day animal fat (INS-L), or with 263 g/day animal fat (CON). Jugular vein catheters were inserted through the ear vein at 1.5 days before weaning to asses plasma insulin and IGF-1 concentrations. After estrus, all sows received a standard gestation diet until slaughter at days 42 to 43 of pregnancy. The dextrose plus starch-diets enhanced the postprandial insulin response in a dose-dependent manner (e.g. at day 2 insulin area under the curve was 4516 μU/444 min for CON, 8197 μU/444 min for INS-L and 10 894 μU/444 min for INS-H; s.e.m. = 694; P < 0.001), but did not affect plasma IGF-1 concentrations during the first 3 days of WEI. Follicle development and subsequent luteal, fetal and placental development and uniformity were not affected by the dietary treatments, nor related to plasma insulin and IGF-1 concentrations during WEI. Pre-weaning plasma insulin and IGF-1 concentrations were negatively related to sow body condition loss during lactation, but were not related to subsequent reproduction characteristics. This study shows that dietary dextrose plus starch are effective in stimulating insulin secretion (both postprandial peak and long-term concentration), but not IGF-1 secretion during the first 3 days after weaning in multiparous sows. The extreme insulin-stimulating diets during WEI did, however, not improve follicle development, or subsequent development and uniformity of fetuses and placentas in these high-prolific sows (27.0 ± 0.6 ovulations; 18.6 ± 0.6 vital fetuses).

The component of variance attributable to maternal lineage for type traits in the UK Holstein Friesian dairy population was estimated. First lactation type classification records of 33 325 contemporary cows, classified between 1996 and 1998 were used in the analysis. Maternal pedigree records were traced back to 1960 to establish maternal lineages. The tracing resulted in cows being assigned to 10 332 cow families with more than one cow per family. Sixty-six percent of the cows were in families of less than five. The traits comprised 16 linear type traits, a total score trait, four composite scores and measures of temperament and ease of milking. Univariate analysis of each trait was performed using residual maximum likelihood, with and without a maternal lineage component. A principal component analysis used a scree test to determine the number of independent traits being considered in-order to establish a level of significance for the test statistic. It was found that eight principal components were responsible for the variation in type. The composite body score trait was found to have a 1·5% component of maternal lineage variance, significant at the 5% level. No other traits showed a significant maternal lineage variance component.

The aim of this experiment was to determine the mechanisms involved in changes in the production of cashmere as a consequence of genetic selection. Skin follicle parameters and pattern of cashmere growth were compared in two selected lines of Scottish cashmere goats and a randomly bred control line. One line, the fine line, had been selected for low fibre diameter, and this had resulted in lower fibre diameter, but the weight of cashmere produced had also been reduced. Selection for fibre quantity and quality to give maximum financial return (the value line) had increased cashmere weight without a significant increase in cashmere diameter.

Skin follicle density and the ratio of secondary to primary follicles (S/P ratio) were measured at 5 months of age in 25 female kids from each line. The density of follicles in the value line was greater (P · 0.05) than that in the fine or control lines (means were 21·8, 19·8 and 20·1 follicles per mm2 respectively, s.e.d. 0.73). S/P ratio increased (P · 0.001) from control to fine to value lines (means were 6.5, 7.7 and 8.4 respectively, s.e.d. = 0.30).

The rate of cashmere growth (length), peak cashmere length, the duration of the cashmere growing period and dates of initiation and cessation of growth were measured in the same 25 goats from each line between 2 and 3 years of age. These traits were estimated from the regression of measurements of staple length taken at approximately 6-weekly intervals from the start of the growing period until peak staple length was reached. Measurements were made on the shoulder, mid side and hip. There was no difference in cashmere growth rate between the selection lines (average 0·29 (s.e. 0.006) mm/day). Cashmere growth started earliest in the value line and latest in the fine line but the date of cessation of growth was not different. This affected the duration of the growing period which was 183, 163 and 214 days (s.e.d. 9.6, P · 0.001) for the control, fine and value lines respectively. Peak staple length of cashmere was longest in the value line.

Increased weight of cashmere in the value line was brought about through an increase in the number of secondary follicles and by an increase in the length of cashmere due to an increase in the duration of the growing period.

In the mink industry, feed costs are the largest variable expense and breeding for feed efficient animals is warranted. Implementation of selection for feed efficiency must consider the relationships between feed efficiency and the current selection traits BW and litter size. Often, feed intake (FI) is recorded on a cage with a male and a female and there is sexual dimorphism that needs to be accounted for. Study aims were to (1) model group recorded FI accounting for sexual dimorphism, (2) derive genetic residual feed intake (RFI) as a measure of feed efficiency, (3) examine the relationship between feed efficiency and BW in males (BWM) and females (BWF) and litter size at day 21 after whelping (LS21) in Danish brown mink and (4) investigate direct and correlated response to selection on each trait of interest. Feed intake records from 9574 cages, BW records on 16 782 males and 16 875 females and LS21 records on 6446 yearling females were used for analysis. Genetic parameters for FI, BWM, BWF and LS21 were obtained using a multivariate animal model, yielding sex-specific additive genetic variances for FI and BW to account for sexual dimorphism. The analysis was performed in a Bayesian setting using Gibbs sampling, and genetic RFI was obtained from the conditional distribution of FI given BW using genetic regression coefficients. Responses to single trait selection were defined as the posterior distribution of genetic superiority of the top 10% of animals after conditioning on the genetic trends. The heritabilities ranged from 0.13 for RFI in females and LS21 to 0.59 for BWF. Genetic correlations between BW in both sexes and LS21 and FI in both sexes were unfavorable, and single trait selection on BW in either sex showed increased FI in both sexes and reduced litter size. Due to the definition of RFI and high genetic correlation between BWM and BWF, selection on RFI did not significantly alter BW. In addition, selection on RFI in either sex did not affect LS21. Genetic correlation between sexes for FI and BW was high but significantly lower than unity. The high correlations across sex allowed for selection on standardized averages of animals’ breeding values (BVs) for RFI, FI and BW, which yielded selection responses approximately equal to the responses obtained using the sex-specific BVs. The results illustrate the possibility of selecting against RFI in mink with no negative effects on BW and litter size.

Stochastic simulation was used to compare selection response and rate of inbreeding in four nucleus breeding systems and a sire referencing scheme for sheep: an open nucleus system (ONS), an open nucleus system with sequential selection of the nucleus (ONS-S), a sire referencing scheme (SRS) and a dispersed open nucleus system (DONS). Selection was based on best linear unbiased prediction of breeding values for a single trait measurable on all individuals prior to selection. Selection in a population of 1200 ewes equally divided into 10 flocks was simulated over a 15-year period. The mean rate of genetic gain was proportionately about 0-15 higher in ONS-S and DONS compared with ONS and SRS. The rate of inbreeding in SRS was considerably lower and in ONS-S, considerably higher, than in the other systems. The level of prolificacy in the population did not influence the relative ranking of the breeding systems but may have implications for their optimal structure.

Two methods of estimating body fat in vivo in cattle, namely measurement of body water by dilution of deuterium oxide and subcutaneous adipose-cell size, were studied in mature cows and compared with a classical method based on dissection of a sample joint.

Total body fat, measured after complete dissection of 12 dry cows, varied between 64 and 185g/kg body weight. Rib fat and adipose-cell diameter were related positively, while body water was related negatively to total body fat. The equations for prediction of total body fat were sufficiently accurate (s.d. = 10·1 to 11·5 g total body fat per kg body weight) to warrant further examination, and adipose-cell diameter was as accurate as body water.

Castrated and entire Boer bucks (no. = 60) in groups of between three and five animals were slaughtered at 5,15, 30, 45, 60, 75, 90 and 105 kg live weight (5- and 15-kg animals were not castrated). Ultimate pH, muscle colour (subjective and objective measurement), subcutaneous fat colour, total pigment concentration, shear force values and eating quality were investigated. The ultimate pH o/longissimus muscle increased from 5-7 to 6-2 (P < 0-05) as animals were slaughtered at heavier weights. Slaughter weight had an influence on chromameter muscle colour (L*, a*, b* values) and subjective muscle colour scores recorded using a nine-point colour scale (P < 0-05) for both entire and castrated bucks. Muscle redness (a* values) and subjective muscle colour scores increased gradually in older animals while muscle lightness and yellowness (L* and b* values) decreased. Subcutaneous fat colour became more yellow at heavier slaughter weights (P < 0-05). Shear force values were affected (P < 0-05) by slaughter weight but not by castration of bucks. All eating quality scores were influenced by slaughter weight but not by castration, and flavour, as predicted by eating quality scores, was the most important attribute that contributed to overall acceptability of the goat meat.

The intake of ten 5-year-old Masham ewes with good teeth, five 7-year-old Mashams with poor teeth and nine 10-year-old ewes with poor teeth was measured when they were offered long (35·1 cm) or short grass (3·8 cm) outdoors or poor quality hay indoors. The young ewes ate significantly more grass and hay than the old ewes, but the difference in daily intake was greater with long grass (1473 v. 751 g organic matter per head) and with hay (895 v. 421) than with short grass (617 v. 407). The intermediate age ewes ate as much of the long grass and of the hay as the young ewes, but less of the short grass. This suggests that age influenced intake more than did tooth condition, except when short grass was offered.

Within the oldest but not within the intermediate group of ewes, there was a significant correlation between the number of incisors and organic matter intake, except with the long grass, but there was no correlation between the number of cheek teeth and intake. When offered hay, the only group with a reduced in vivo digestibility was the intermediate group of ewes, the other two groups having a similar digestibility.

There was no correlation between number of incisors or number of molars and in vivo digestibility.

High-starch diets (HSDs) fed to high-producing ruminants are often responsible for rumen dysfunction and could impair animal health and production. Feeding HSDs are often characterized by transient rumen pH depression, accurate monitoring of which requires costly or invasive methods. Numerous clinical signs can be followed to monitor such diet changes but no specific indicator is able to make a statement at animal level on-farm. The aim of this pilot study was to assess a combination of non-invasive indicators in dairy cows able to monitor a HSD in experimental conditions. A longitudinal study was conducted in 11 primiparous dairy cows fed with two different diets during three successive periods: a 4-week control period (P1) with a low-starch diet (LSD; 13% starch), a 4-week period with an HSD (P2, 35% starch) and a 3-week recovery period (P3) again with the LSD. Animal behaviour was monitored throughout the experiment, and faeces, urine, saliva, milk and blood were sampled simultaneously in each animal at least once a week for analysis. A total of 136 variables were screened by successive statistical approaches including: partial least squares-discriminant analysis, multivariate analysis and mixed-effect models. Finally, 16 indicators were selected as the most representative of a HSD challenge. A generalized linear mixed model analysis was applied to highlight parsimonious combinations of indicators able to identify animals under our experimental conditions. Eighteen models were established and the combination of milk urea nitrogen, blood bicarbonate and feed intake was the best to detect the different periods of the challenge with both 100% of specificity and sensitivity. Other indicators such as the number of drinking acts, fat:protein ratio in milk, urine, and faecal pH, were the most frequently used in the proposed models. Finally, the established models highlight the necessity for animals to have more than 1 week of recovery diet to return to their initial control state after a HSD challenge. This pilot study demonstrates the interest of using combinations of non-invasive indicators to monitor feed changes from a LSD to a HSD to dairy cows in order to improve prevention of rumen dysfunction on-farm. However, the adjustment and robustness of the proposed combinations of indicators need to be challenged using a greater number of animals as well as different acidogenic conditions before being applied on-farm.

The cellular characteristics of dissected carcass (subcutaneous and intermuscular fat) and non-carcass (kidney fat, omental and mesenteric fat) fat partitions were examined at maturity in a total of 34 rams and ewes from flocks of Peppin Merino sheep selected for high (weight-plus) or low (weight-minus) weaning weight and from a randomly bred control flock. Strain and sex effects on the rate of change in adipocyte volume in each fat partition relative to the change in chemical-fat weight in that partition, were examined in 60 immature animals.

Selection for high or low weaning weight had no effect on adipocyte volume in the mature animals, with the increased weight of fat in the weight-plus animals due to an increased number of adipocytes in the dissected fat partitions. Consequently, hyperplasia had a greater contribution to increases in chemical-fat weight in the weight-plus, compared with the weight-minus animals.

Mature ewes had larger and fewer adipocytes in the subcutaneous and intermuscular partitions than the mature rams, whereas there was no difference between the sexes in adipocyte volume in the kidney, omental and mesenteric fat partitions. Mature ewes had fewer adipocytes than the mature rams in the subcutaneous, intermuscular, omental and mesenteric fat partitions. With the exception of the kidney fat partition, there was no sex effect on the relative contribution of hypertrophy to increases in chemical-fat weight of the dissected carcass and non-carcass fat partitions.

Bayesian theory is applied to compare the characteristics of the estimated lactation curves of two groups of 5-year-old Merino ewes. The diets of the two groups were supplemented respectively by DL-methionine and maleyl-DLmethionine. The purpose is to illustrate the Bayesian approach when analysing for the effect of supplement on the lactation pattern of the sheep. Using Wood's model, the posterior distributions of the model parameters are determined for the two groups. This is achieved by assuming a hierarchical Bayes model and applying the Gibbs sampler, a sampling based computer intensive algorithm that is very efficient in obtaining marginal distributions of functions of parameters. The Gibbs sampler enables us to obtain marginal posterior distribution of characteristics of the lactation curve such as peak yield, time of peak yield, persistency and total milk yield. The results are notable differences in the marginal posterior distributions of mean peak milk yield and mean total yield. The posterior probability that the mean peak milk yield of the group supplemented by maleyl-DL-methionine is higher than that of the group with DL-methionine supplement is 0·98, while the same probability for mean total yield is 0·83.

The nine possible breed types resulting from the use of Angus, Boran and Red Poll bulls on Ankole, Boran and local Zebu cows were represented in the experiment. Sex, period of birth and year of birth had significant effects, at practically all ages, on body weights of calves measured at three-monthly intervals from birth to two years. Age of dam had a significant effect on calf weight at birth but not thereafter. Previous parous state of dam had only few apparently significant effects on calf weights at different ages. It appeared that beneficial effects of a good pre-weaning maternal environment might be retained, as there was no strong evidence of post-weaning compensatory growth for pre-weaning maternal effects due to age and previous parous state of dam.

Two groups of 28 Finnish Landrace (FL) lambs were given (group Mg) or denied (group O) access to a magnesium (Mg)-rich mineral mixture to establish its role in the hitherto frequent development of diarrhoea in the flock. Diarrhoea developed in most lambs but became marginally worse in group Mg (P < 0·05) by weaning. At weaning, 28% of the lambs had salivary sodium: potassium (Na: K) ratios < 4 indicating Na deficiency but pasture was not low in Na (60·9 mmol/kg dry matter (DM)) and providing the mineral mixture (which also contained Na) did not alleviate the deficiency. Raised plasma pepsinogen (PP) concentrations were indicative ofabomasal parasitism and all lambs were drenched with levamisole. Groups were subdivided at weaning, either continuing on their previous treatments (groups Mg/Mg and O/O) or being offered pure salt (NaCl) (groups Mg/Na and O/Na). Mineral consumption was measured from weaning and varied widely between groups and with time for the first 2 weeks. Early consumption was maximal at 19·6 g per head per day in group Mg/Mg and zero in group Mg/Na and faecal DM was significantly lower in the former group (165 v. 223 (s.d. 16·9) g/kg DM). All groups showed an improvement in Na status after weaning followed by a decline and NaCl consumption showed opposite changes about a mean of 6·3 g per head per day: faecal DM became uniformly low (ca. 200 g/kg fresh weight) in all groups. A further rise in PP prompted a second treatment with levamisole 6 weeks after weaning. When salivary Na: K was low (1 and 7 weeks after weaning), a significant relationship (P = 0·002) was found between salivary K (mmol/l), faecal DM (g/kg) and plasma pepsinogen (PP U per l;):

K = 22·9 + 4·5 PP – 0·047 DM (d.f. 82: r = 0·34).

Nematodiasis may have caused an ion imbalance and an associated diarrhoea, inducing a craving for NaCl which was ill-met by a mixture rich in laxative Mg.

1. Some characteristics are described of 10 steer progeny of a Friesian bull which is known to have carried the factor for muscular hypertrophy.

2. On average these steers had a higher birth weight, lighter hide and liver, smaller feet and cannon bones, a lower percentage of fat and higher percentage of lean in the 10th rib joint, than the progeny of three other Friesian bulls reared at the same time and under the same conditions.

3. No one character was an adequate criterion for separating affected from normal progeny. It appears possible that the bull concerned was homozygous for the double muscling gene, and that all his progeny showed one or more symptoms of the condition.

Starch is an important energy-providing nutrient for dairy cows that is most commonly provided from cereal grains. However, ruminal fermentation of large amounts of easily degradable starch leads to excessive production and accumulation of volatile fatty acids (VFA). VFA not only play a vital role in the energy metabolism of dairy cows but are also the main cause of ruminal acidosis and depressed feed intake. The aim of the present study was to compare maize cob silage (MCS) as an energy supplement in rations for dairy cows with highly rumen-digestible rolled barley and with sodium hydroxide wheat (SHW), which has a higher proportion of by-pass starch than barley. Two studies were carried out: (1) a production study on 45 Danish Holstein cows and (2) an intensive study to determine digestibilities, rumen fermentation patterns and methane emission using three rumen-cannulated Danish Holstein cows. Both studies were organised as a 3×3 Latin square with three experimental periods and three different mixed rations. The rations consisted of grass-clover silage and maize silage (~60% of dry matter (DM)), rapeseed cake, soybean meal, sugar beet pulp and one of three different cereals as a major energy supplement: MCS, SHW or rolled barley (~25% of DM). When MCS replaced barley or SHW as an energy supplement in the mixed rations, it resulted in a lower dry matter intake; however, the apparent total tract digestibilities of DM, organic matter, NDF, starch and protein were not different between treatments. The energy-corrected milk yield was unaffected by treatment. The fat content of the milk on the MCS ration was not different from the SHW ration, whereas it was higher on the barley ration. The protein content of the milk decreased when MCS was used in the ration compared with barley and SHW. From ruminal VFA patterns and pH measures, it appeared that MCS possessed roughage qualities with respect to rumen environment, while at the same time being sufficiently energy rich to replace barley and SHW as a major energy supplement for milk production. The environmental impact, expressed as methane emissions, was not different when comparing MCS, SHW and barley.

A nucleus dairy population using multiple ovulation and embryo transfer (MOET) was stochastically modelled with overlapping generations. The aim was to investigate the feasibility of controlling inbreeding in MOET breeding schemes using more realistic parameters for embryo recovery and best linear unbiased prediction (BLUP) for genetic evaluation. Four different cases (involving the culling of donors, more donors and the use of organized progeny testing of nucleus bulls) were studied in combination with nested and factorial designs. Further studies involved modifications of the selection index, including subtracting parental breeding values, inflating the genetic variance in the BLUP evaluation and penalizing inbred animals; these options were examined both with and without organized progeny testing. The effects of applying these schemes on both genetic response and rate of inbreeding were investigated. The results stressed the importance of incorporating progeny testing into MOET schemes for value of reducing inbreeding whilst maintaining genetic progress. There was no significant difference between nested and factorial designs. In the absence of progeny testing the inflation of genetic variance was more effective than subtracting parental breeding values at controlling inbreeding; however incorporating progeny testing made the latter strategy more potent and the superiority of inflating the genetic variance was in this case much smaller and non-significant.