D‐loop sequence mitochondrial DNA variability of Sarda goat and other goat breeds and populations reared in the Mediterranean area

To provide useful knowledge on goat breed origin and history, we studied the mitochondrial DNA (mtDNA) of 69 goats from five different breeds, Camosciata delle Alpi, Maltese, Nubian, Saanen and Sarda, and one population, the Tunisian. All goats analysed displayed a moderate haplotype and nucleotide diversity. The highest was in the Sarda – the autochthonous breed reared in Sardinia. On the basis of mtDNA control region sequences, animals showed a high genetic haplotype diversity, 35 haplotypes were each represented by a single sequence and only a few haplotypes were shared among the animals. New haplotypes of goats reared in the Mediterranean area were identified and the majority of Italian goats belonged to haplogroup A. This result confirmed worldwide distribution and diversity of haplogroup A.     

Trends in genotype frequency resulting from breeding for resistance to classical scrapie in Belgium (2006~2011)

In sheep, susceptibility to scrapie is mainly determined by codons 136, 154, and 171 of the PRNP gene. Five haplotypes are usually present (ARR, ARQ, ARH, AHQ, and VRQ). The ARR haplotype confers the greatest resistance to classical scrapie while VRQ renders animals most susceptible. In 2004, the European Union implemented a breeding program that promotes selection of the ARR haplotype while reducing the incidence of VRQ. From 2006 to 2011 in Belgium, frequency for the ARR/ARR genotypes increased from 38.3% to 63.8% (n = 6,437), the ARQ haplotype diminished from 21.1% to 12.9%, and the VRQ haplotype decreased from 2.0% to 1.7%. The status of codon 141, a determinant for atypical scrapie, was also evaluated. Out of 27 different breeds (n = 5,163), nine were abundant. The ARR/ARR frequency increased in eight of these nine major breeds. The selection program has had a major impact on the ARR haplotype frequency in Belgium. However, the occurrence of atypical scrapie represents a critical point for this program that warrants the continuous monitoring of scrapie. Additionally, genotype frequencies among the breeds varied greatly. Texel, a breed that is common in Belgium, can still be selected for due to its average ARR frequency.     

利用mtDNA Cytb基因分析湘黔川五个山羊品种系统发育

试验对四川板角山羊、贵州白山羊、贵州黑山羊、贵州麻羊及湖南马头山羊5个山羊品种,共计69个个体的Cytb基因片段进行测序分析比较。结果显示,69个山羊Cytb基因序列均为长1140bp的同源基因,共发现17个变异位点,观察到14种单倍型;5个山羊品种的群体遗传多样性在0．442—0．889之间,核苷酸多样度从0．00145—0．00253。表明5个山羊遗传多样性属于中等;5个山羊品种可分为2大类群,即：贵州黑山羊、贵州麻羊、贵州白山羊和湖南马头山羊4个品种为一类,四川板桥山羊1个品种为另一类。     

Determining the relationship between restorative potential and size of a gene bank to alleviate the risks inherent in a scrapie eradication breeding programme

Breeding plans are being adopted in many countries to eradicate scrapie from the sheep populations. The European plans are based on selection for increased frequency of the resistant ARR haplotype and removal of the most scrapie susceptible haplotype (VRQ). This approach of a genotype eradication breeding programme incurs a number of risks including those associated with novel spongiform encephalopathy causing agents that are as yet unknown, but may emerge in the future and the possible loss of favourable attributes of a breed either through linkage or pleiotropic effects when selecting on a specific haplotype. Semen gene banks have been proposed to provide the potential for future reintroduction of removed haplotypes. Computer simulations were run for hill, crossing and terminal breed types to investigate the restorative potential of a gene bank required for the reintroduction of an alternative haplotype in the future. Differences existed in the restorative potential between the different breed types considered. This was largely dictated by variable levels of fertility, litter size, survival and mating ratio. It was shown that terminal breeds would require two and a half times as many semen straws as hill breeds to produce the same frequency of ewes homozygous for the desired haplotype in the population after a ten year reintroduction period.     

南疆绒山羊的培育

南疆白绒山羊是通过对当地山羊的选育和杂交改良，经过近20年的努力育成的。通过本品种选育，横交固定，饲养管理等技术的实施，培育出了体型外貌一致，生产性能高，遗传性能稳定的新品种白绒山羊7．6万余只，并且建成年生产种羊达1000只的种羊生产基地，采取边培育边推广的方法，使阿克苏地区绒山羊平均个体产绒量达175．6g，取得了明显的经济，社会效益。     

Comparison of meat quality characteristics and fatty acid composition of finished goat kids from indigenous and dairy breeds

The aim of the study was to compare the certain carcass and meat quality traits and also fatty acid composition of goat kids from indigenous breeds (Gokceada and Hair Goat) and dairy breeds (Saanen and Maltese). A total 40 male kids from Saanen, Gokceada, Maltese and Hair Goat breeds were collected from commercial farms after weaning. Kids were finished for 56 days with grower concentrate and alfalfa hay in the sheepfold until slaughter. Higher mean values were found for Saanen kids in terms of slaughter weight, hot carcass weight and real dressing compared with Maltese, Hair Goat and Gokceada kids under the same intensive conditions. On the other hand, there were no significant differences between breeds in terms of instrumental meat quality traits, except meat colour. Meat from Gokceada and Hair Goat kids had higher lightness and Hue angle values than Saanen kids after 24 h of blooming. High meat redness values were observed for Saanen kids after 0 and 1 h of blooming. Panellist appreciated cooked meat from Saanen and Maltese kids in overall acceptability. If the fatty acid composition of meat was taken into consideration, kids from Saanen and Gokceada breeds displayed better values, because of the lower ?SFA percentage and higher desirable fatty acids (C18:0?+?ΣMUFA?+?ΣPUFA) percentage than Maltese and Hair Goat kids. Our results indicate that male kids for Saanen which is dairy breed could be assessable for quality goat meat production.     

Comparison of casein haplotypes between two geographically distant European dairy goat breeds.

The aim of this paper was to characterize the diversity among haplotypes based on 22 single nucleotide polymorphisms (SNPs) and one deletion within four casein genes in two geographically distant goat populations, the Sicilian Girgentana breed and the Norwegian goat breed. Forty Girgentana goats were genotyped for the aforementioned polymorphisms and the resulting data set was compared with 436 goats from the Norwegian population previously genotyped for these markers. Several casein gene polymorphisms were not in Hardy-Weinberg equilibrium either in Girgentana, or in the Norwegian breed. The SNP haplotype frequencies for the four casein genes were calculated and despite the large geographical distance and phenotypic divergence between these breeds, a proportion of casein loci haplotypes were found to be identical between both Norwegian and Girgentana goats. However, for the CSN2 gene there were no common haplotypes between the two populations. The level of linkage disequilibrium between the casein genes was less in the Girgentana population than in the Norwegian population.     

Caprine prion gene polymorphisms are associated with decreased incidence of classical scrapie in goat herds in the United Kingdom

ABSTRACT: The application of genetic breeding programmes to eradicate transmissible spongiform encephalopathies in goats is an important aim for reasons of animal welfare as well as human food safety and food security. Based on the positive impact of Prnp genetics on sheep scrapie in Europe in the past decade, we have established caprine Prnp gene variation in more than 1100 goats from the United Kingdom and studied the association of Prnp alleles with disease phenotypes in 150 scrapie-positive goats. This investigation confirms the association of the Met142 encoding Prnp allele with increased resistance to preclinical and clinical scrapie. It reveals a novel association of the Ser127 encoding allele with a reduced probability to develop clinical signs of scrapie in goats that are already positive for the accumulation of disease-specific prion protein in brain or periphery. A United Kingdom survey of Prnp genotypes in eight common breeds revealed eleven alleles in over thirty genotypes. The Met142 encoding allele had a high overall mean allele frequency of 22.6%, whereas the Ser127 encoding allele frequency was considerably lower with 6.4%. In contrast, a well known resistance associated allele encoding Lys222 was found to be rare (0.9%) in this survey. The analysis of Prnp genotypes in Mexican Criollas goats revealed nine alleles, including a novel Phe to Leu substitution in codon 201, confirming that high genetic variability of Prnp can be found in scrapie-free populations. Our study implies that it should be feasible to lower scrapie prevalence in goat herds in the United Kingdom by genetic selection.     

Effects of treadmill exercise on sweating in three breeds of goats

OBJECTIVE: To compare the sweating responses of three breeds of goats to exercise at 30 degrees C. DESIGN: Factorial experiment with two goats of each of three breeds exercised for 60 min at 3 km/h and 30 degrees C on 6 days. PROCEDURE: Two mature females of the Anglo-Nubian, Saanen and Toggenburg breeds were used. Rectal temperature, respiration rate and sweating rate at three sites were recorded every 20 min during six replicates of exercise at 48 h intervals on a treadmill. RESULTS: Respiration rate varied with time and breed (P < 0.01) and increased from 20 +/- 2 breaths/min to 135, 195 and 260/min after 60 min exercise in Anglo-Nubian, Saanen and Tottenburg goats, respectively. Bread differences in rectal temperature were small but significant (P < 0.001), and mean values increased from 38.9 degrees C before exercise to 39.7 degrees C after 1 h exercise. The breed x sites interaction for sweating was significant (P < 0.01). On the rump breed differences in sweating rate were not significant. On the loin, Toggenburg goats started to sweat most rapidly and reached maximal values of 80.2 +/- 10.6 g/m2/h after 20 min and then decreased to 70.0 +/- 4.3 g/m2/h at 60 min. Sweating rate on the ear was highest in Toggenburg goats, followed by those of Saanen and Anglo-Nubian goats (P < 0.05), but the differences were small (7 g/m2/h); peak values of 67.3 to 76.1 g/m2/h were recorded after 20 min. CONCLUSION: Respiration and sweating rates increased significantly during exercise in all three breeds of goats, but breed differences were marked only for respiration rate. The goats sweated more on the rump than on the loin on ear, with peak values after 40 min of exercise.     

Genetic phylogeography and maternal lineages of 18 Chinese black goat breeds

To understand the origin and genetic phylogeography of Chinese black goats, variations of mitochondrial DNA were characterised with 394 goats from 18 breeds, including 91 new individuals from regions poorly studied until now. Comparison of a 481-bp segment revealed a total of 192 haplotypes with 141 variable sites. The haplotype and nucleotide diversities ranged from 0.782?±?0.079 to 1.000?±?0.020 and from 0.009?±?0.001 to 0.045?±?0.006, respectively, indicating a relatively high genetic diversity in Chinese black goats. Phylogenetic analyses identified five haplogroups (A, B₁, B₂, C and D). The dominant haplogroups A, B₁ and B₂ were distributed in most of breeds, while the haplogroups C and D were only presented in the breeds located in north or northwest of China. Analysis of molecular variance and multidimensional scaling plot of F _ST analyses indicated no obvious geographic structure among breeds. Furthermore, the migration rates revealed that a wide range of gene flow or gene exchange occurred among breeds, which may result in the weak geographic structure of Chinese black goats. Population expansion analysis based on mismatch distribution indicated that two expansion events in Chinese black goats occurred at 10 and 28 mutational time units. Finally, our findings indicate the multiple maternal origins of Chinese black goats and more gene flow (female-mediated) which occurred during their domestic and breeding histories.     

Perspectives of a scrapie resistance breeding scheme targeting Q211, S146 and K222 caprine PRNP alleles in Greek goats

The present study investigates the potential use of the scrapie-protective Q211 S146 and K222 caprine PRNP alleles as targets for selective breeding in Greek goats. Genotyping data from a high number of healthy goats with special emphasis on bucks, revealed high frequencies of these alleles, while the estimated probabilities of disease occurrence in animals carrying these alleles were low, suggesting that they can be used for selection. Greek goats represent one of the largest populations in Europe. Thus, the considerations presented here are an example of the expected effect of such a scheme on scrapie occurrence and on stakeholders.     

Administration of hCG 5 days after Breeding and Reproductive Performance in Nulliparous Dairy Goats

The objective of this study was to investigate the effect of hCG administration 5 days after breeding on plasma progesterone (P4) concentration and reproductive performance of oestrous-induced nulliparous dairy goats. A total of 59 nulliparous goats (36 Alpine and 23 Saanen) received intravaginal sponges with 60 mg medroxyprogesterone acetate for 9 days plus 200 IU equine chorionic gonadotrophin (eCG) and 22.5 microg d-cloprostenol 24 h before sponge removal. After detection of oestrus (day of oestrus = day 0) and breeding, 49 females were randomly assigned, according to the breed, into two treatments (T1 and T2). In T1 (n = 25) and T2 (n = 24), animals received intramuscular injection of 1 ml of saline solution (control) or 250 IU hCG, respectively, 5 days after breeding. Plasma P4 concentration (ng/ml) was determined from blood sampled on days 0, 5, 7, 13, 17, 21, 28 and 45 after breeding. Animals were scanned by transrectal ultrasound (5 MHz probe) on days 35 and 70 after breeding for detection of pregnancy. Plasma P4 concentration did not differ (p > 0.05) between treatments in all days, but it was increased (p < 0.05) in Saanen than in Alpine goats from days 13 to 45. Pregnancy and parturition rates, litter size and gestation period were similar (p > 0.05) to treatments and breeds. Results of this study indicate that human chorionic gonadotrophin (hCG) administration 5 days after breeding did not significantly alter reproductive performance in dairy nulliparous goats and that plasma P4 differed between Saanen and Alpine goats.     

Resistance to classical scrapie in experimentally challenged goats carrying mutation K222 of the prion protein gene

ABSTRACT: Susceptibility of sheep to scrapie, a transmissible spongiform encephalopathy of small ruminants, is strongly influenced by polymorphisms of the prion protein gene (PRNP). Breeding programs have been implemented to increase scrapie resistance in sheep populations; though desirable, a similar approach has not yet been applied in goats. European studies have now suggested that several polymorphisms can modulate scrapie susceptibility in goats: in particular, PRNP variant K222 has been associated with resistance in case-control studies in Italy, France and Greece. In this study we investigated the resistance conferred by this variant using a natural Italian goat scrapie isolate to intracerebrally challenge five goats carrying genotype Q/Q 222 (wild type) and five goats carrying genotype Q/K 222. By the end of the study, all five Q/Q 222 goats had died of scrapie after a mean incubation period of 19 months; one of the five Q/K 222 goats died after 24 months, while the other four were alive and apparently healthy up to the end of the study at 4.5 years post-challenge. All five of these animals were found to be scrapie negative. Statistical analysis showed that the probability of survival of the Q/K 222 goats versus the Q/Q 222 goats was significantly higher (p = 0.002). Our study shows that PRNP gene mutation K222 is strongly associated with resistance to classical scrapie also in experimental conditions, making it a potentially positive target for selection in the frame of breeding programs for resistance to classical scrapie in goats.     

A comparison of holstein friesians,Dutch friesians and Dutch red and whites. II. Economic synthesis with different pricing systems for milk and meat

The influences of different milk and meat prices on the economic differences between Holstein Friesians from North America (HF), Dutch Friesians (DF) and Dutch Red and Whites (DRW) were studied. The basic biological data came from a within-herd comparison of the three breeds. Milk prices used were as follows: M₁ was the current price in The Netherlands (negative price for the volume of milk), in M₂, the penalty for the volume of milk was zero; in M₃, the current penalty was doubled; in M₄ the net price for 1 kg milk was 20% lower, and in M₅ the net milk price was 20% higher. Meat prices in S₁ were the prices based on the actual situation; in S₂ there was no payment for differences in slaughter quality between cows and calves; in S₃ the premium payment for higher slaughter quality was doubled; in S₄ the meat prices were 20% lower and in S₅ the meat prices were 20% higher. The economic differences between the HF and the DF varied from +Dfl. 141 (M₂S₂) to –Dfl. 95 (M₃S₃). Differences between the HF and the DRW were from +Dfl. 263 (M₂S₂) to – Dfl. 93 (M₃S₃). Differences between the DF and the DRW varied from +Dfl. 142 (M₃S₂) to – Dfl. 13 (M₄S₃). These results indicate that no breed was economically superior to all other breeds under all pricing systems. The relative economic advantage or disadvantage of a breed is strictly a function of relative prices for milk and meat.     

Characterization of the village goat production systems in the rural communities of the Eastern Cape,KwaZulu-Natal,Limpopo and North West Provinces of South Africa

Expansion of goat improvement programs requires exploration of the factors that influence the production system and breeding initiatives. Characterization of goat breeds or populations is crucial in providing information on prevalent goat types and their attributes and may suffice as a guideline on conservation, development, and selection for improved productivity. This study investigated the existing village goat production system and phenotypic diversity of the different village populations from four South African provinces. The study further investigated the use of phenotypic attributes to classify goats to breeds or populations. Data was collected from 142 households in 26 villages of the Eastern Cape (n?=?2 villages), KwaZulu-Natal (n?=?6 villages), Limpopo (n?=?13 villages), and North West (n?=?5 villages) provinces through a survey. Individual interviews and focus group discussions revealed that the mean goat herd size per household was least in Limpopo at 13.2?±?12.40 and highest in Eastern Cape (34.18?±?28.36). Flocks had more (p?<?0.05) adults than kids, and the distribution of breeding animals was biased towards does and less bucks. Goats were kept mainly for meat, for selling, and for ritual ceremonies. The goat production system was mainly scavenging. Goat health was a major challenge across households and villages. Qualitative traits such coat, horn, ears, and wattle characteristics were recorded for populations of village goats (n?=?319) and a feral Tankwa breed (n?=?50). The dominant coat pattern was plain (74.53%) with black as the most common coat color (31.98%). Across breeds, a majority (88.08%) of the goats had horns, and 7.59% had wattles while 56.64% had beard. Adult goats (<3 years; n?=?398) were further analyzed for five quantitative traits of chest girth, height, length, and pin bone and there were significant (p?<?0.05) breed differences in all. A stepwise discriminatory procedure was used to rank the quantitative traits according to their discriminatory power to separate breeds or populations. Significant traits were then subjected to canonical discriminant analysis for principle component analysis. Based on the quantitative traits, the Tankwa, Xhosa, and Tswana goats formed their own cluster separated from commercial meat type breeds and the Venda and Zulu ecotypes. The discriminant function analysis correctly classified 90.41% of the Zulu goats and 82.93% of the Xhosa village populations. None of the Savanna goats were correctly classified. The study demonstrated diversity in village goat populations and production systems, which would allow for within population selection in genetic improvement programs. The heterogeneity in the phenotypic traits in the village goats is reflective of the role of village production systems in the maintenance of animal diversity in local populations.     

High prevalence of <Emphasis Type="Italic">Eimeria</Emphasis> infection in dairy goats in Shaanxi province,northwestern China

A survey of dairy goats for infection with Eimeria species of coccidia was conducted in the Shaanxi province, northwestern China between December and November 2010, including Saanen and Guanzhong breeds. A total of 584 fecal samples (250 and 334 from Saanen and Guanzhong dairy goats, respectively) in six farms were collected. Eimeria oocysts were seen in 568 (97.3%) fecal samples, with six species, namely Eimeria jolchijevi, Eimeria arloingi, Eimeria alijevi, Eimeria caprina, Eimeria hirci, and Eimeria christenseni. The most prevalent were E. arloingi in Saanen and Guanzhong dairy goats, with an overall prevalence of 83.3% and 84.4%, and the lowest prevalence were E. christenseni (26.9%) and E. hirci (20.7%) for Saanen and Guanzhong Dairy goats, respectively. Two or more Eimeria species were commonly presented in all the age groups; 80.0% and 81.4% of positive Saanen and Guanzhong dairy goats carried more than two species, and 1.6% and 6.5% of two breeds had six species. The results of the present survey suggested that Eimeria infection is wide and severe in the Saanen and Guanzhong dairy goats, which suggested that integrated strategies should be implemented to prevent and control coccidial infection in dairy goats in this province.     

PrP genotype frequencies of Quebec sheep breeds determined by real-time PCR and molecular beacons

The allele and genotype frequencies of the prion protein gene (PrP), known to have an impact on scrapie susceptibility, were determined by real-time PCR for 500 Quebec purebred rams. Molecular beacons were very efficient in discriminating the 5 alleles investigated. Polymorphisms at coding positions 136, 154, and 171 of the PrP gene were analyzed using 3 separate real-time PCR reactions and a total of 7 molecular beacons. A total of 4 different alleles (ARQ, ARR, AHR, and VRQ) were observed at different frequencies among the 7 breeds of sheep investigated. Results show that more than 50% of the rams in every breed carried at least one ARR allele, which is considered the most resistant to scrapie. The susceptibility ARQ allele was also present in every breed and together with the ARR allele, they were the most frequent alleles found in Quebec rams. The VRQ allele associated with the highest susceptibility to scrapie occurred in 5 of the 7 breeds, although at low frequencies. Overall, the results indicate that the frequencies of PrP alleles and genotypes in common breeds of sheep in Quebec make it feasible to reduce scrapie risk by selective breeding.     

PRNP haplotype and genotype frequencies in Brazilian sheep: issues for conservation and breeding programs

Polymorphisms of PRNP gene have been strongly correlated to the susceptibility/resistance to scrapie in sheep. Variants at the coding positions 136, 154 and 171 have been the most frequently associated to susceptibility to classical scrapie. The aim of this study was to estimate PRNP haplotype and genotype frequencies in a sample of 1400 sheep from 13 different breeds that are representative of the main production regions in Brazil. A total of four different alleles (ARR, ARQ, AHQ and VRQ) and nine genotypes were observed at different frequencies among the investigated breeds. There were distinct patterns of allelic distribution between naturalized and commercial/specialized breeds and different geographic regions. These results will influence the development and management of breeding and conservation programs and will help to develop Brazilian efforts to avoid scrapie epidemics.     

基于线粒体DNA D-loop区序列分析中国及新西兰奶山羊遗传进化关系

[目的]分析我国地方培育奶山羊品种与国外引进品种的遗传进化关系。[方法]以4个国内奶山羊品种（文登奶山羊、关中奶山羊、崂山奶山羊、雅安奶山羊）和3个新西兰引进奶山羊品种（阿尔卑斯奶山羊、吐根堡奶山羊、萨能奶山羊）为研究对象,采集33只个体的外周血样本,提取血液基因组DNA,利用PCR法扩增线粒体DNA（mitochondrial DNA,mtDNA）D-loop区全长序列,对测序获得的序列进行生物信息学分析,探究不同奶山羊品种的遗传多样性及进化关系。[结果]7个品种奶山羊的mtDNA D-loop区中A、T碱基含量高于G、C碱基含量。共检测到82个多态位点,25个单一多态位点,55个简约信息位点。各品种单倍型多样度（Hd）范围为0.905~1.000,核苷酸多样度（Pi）范围为0.001 51~0.013 32;共存在26种单倍型,文登奶山羊和萨能奶山羊各有5个单倍型,阿尔卑斯奶山羊有4个单倍型,崂山奶山羊、吐根堡奶山羊、关中奶山羊、雅安奶山羊各有3个单倍型;各品种核苷酸平均差异数（K_XY）范围为6.400 00~38.450 00,核苷酸歧异度（D_XY）范围为0.005 79~0.034 76,遗传分化系数（G_ST）范围为0.000 00~0.186 05,遗传分化指数（F_ST）范围为0.231 56~0.971 52。品种间系统发育树表明,文登奶山羊和崂山奶山羊聚为一支;关中奶山羊与3种新西兰奶山羊遗传距离较近,从遗传学角度证实了关中奶山羊由国外奶山羊与地方品种经杂交选育而成;雅安奶山羊与其他品种遗传距离最远。[结论]中国奶山羊存在2个支系起源且未发现群体扩张;中国培育奶山羊品种含有较多的国外奶山羊血统;文登奶山羊与崂山奶山羊亲缘关系较近,雅安奶山羊在遗传进化中可能存在地域隔离。     

Assessment of Progesterone Concentration Using Enzymeimmunoassay, for Early Pregnancy Diagnosis in Sheep and Goats

The objective of this study was to determine a value of serum progesterone (P₄) concentration, assessed using an enzymeimmunoassay (EIA), for the early distinction between pregnant and non‐pregnant ewes and goats. Adult, non‐lactating ewes of Chios (n=53), Berrichon (n=30) and Sfakia (n=45) breeds were synchronized during the breeding season with progestagens and gonadotrophins and mated to fertile rams (Experiment I). Adult, lactating goats of Swiss breeds (Alpine and Saanen, n=104) and indigenous Greek breed (n=45) were synchronized during the transitional season with progestagens, PGF₂α and gonadotrophins. Cervical artificial insemination (AI) with fresh semen was applied once, 42–44 h after sponge removal (Experiment II). Jugular blood samples were collected on day 19 after sponge removal (ewes) or on day 21 after AI (goats) and serum P₄ concentration was determined by EIA. Progesterone concentrations ≥1.0, ≥1.5, ≥2.5 and ≥4.0 ng/ml were tested as indicative of pregnancy. Pregnancy diagnosis was verified on birth. In the case of sheep, using a discriminatory level of 2.5 ng/ml, overall accuracy of pregnancy diagnosis was 91.4% and predictive value of negative and positive diagnoses were 98.3 and 85.3%, respectively. In the case of goats, predictive value of negative diagnosis was 95.8 and 94.0% and predictive value of positive diagnosis 71.3 and 71.7%, for 1.5 and 2.5 ng/ml, respectively; overall accuracy was 79.2% using either level. The other discriminatory levels tested did not improve these results. A significant positive correlation was observed between P₄ concentration and the number of lambs or kids born, and further analysis indicated that this relationship is not a simple linear function. Based on the results of this study, P₄ concentrations of 2.5 ng/ml in the case of ewes and 1.5–2.5 ng/ml in the case of goats, determined with EIA, are proposed as discriminatory levels between pregnant and non‐pregnant animals, at an interval of one oestrous cycle after service.