Blood genetic marker studies of a sheep-goat hybrid and its back-cross offspring

Summary. Blood samples from a female sheep-goat hybrid and its back-cross male offspring were tested for electrophoretic variants of plasma albumin, transferrin and esterase, and of red cell carbonic anhydrase, nucleoside phosphorylase, NADH-diaphorase, 'X'-protein, superoxide dismutase, malic enzyme and haemoglobin. Red cells were also tested for blood group antigens. Both animals showed variants that could not be attributed to either sheep or goat alone, thus confirming previous chromosomal data that the female was a genuine sheep-goat hybrid.     

Blood genetic marker studies of a sheep-goat hybrid and its back-cross offspring

Blood samples from a female sheep-goat hybrid and its back-cross male offspring were tested for electrophoretic variants of plasma albumin, transferrin and esterase, and of red cell carbonic anhydrase, nucleoside phosphorylase, NADH-diaphorase, 'X'-protein, superoxide dismutase, malic enzyme and haemoglobin. Red cells were also tested for blood group antigens. Both animals showed variants that could not be attributed to either sheep or goat alone, thus confirming previous chromosomal data that the female was a genuine sheep-goat hybrid.     

Studies on the transferrins of goats. 3. Evidence for a third transferrin allele

A new allele Tf ^c in serum transferrin of goats is postulated. It was considered that serum transferrins in goats classified into six phenotypes are genetically controlled by three codominant alleles, Tf ^A, Tf ^B and Tf ^c. Frequencies of Tf ^c were low in native goats in Korea, Philipines and Thailand, and this allele is yet to be observed in other breeds of goats.     

Phylogenetic analysis of Sicilian goats reveals a new mtDNA lineage

The mitochondrial hypervariable region 1 (HVR1) sequence of 67 goats belonging to the Girgentana, Maltese and Derivata di Siria breeds was partially sequenced in order to present the first phylogenetic characterization of Sicilian goat breeds. These sequences were compared with published sequences of Indian and Pakistani domestic goats and wild goats. Mitochondrial lineage A was observed in most of the Sicilian goats. However, three Girgentana haplotypes were highly divergent from the Capra hircus clade, indicating that a new mtDNA lineage in domestic goats was found.     

Search for genetic variation in the blood of Norwegian dairy goats reveals a new polymorphism at the HbβA locus

A total of 150 blood samples tested for serum albumin and transferrin and for red cell carbonic anhydrase, phosphoglucomutase, phosphogluconate dehydrogenase, phosphohexose isomerase, nucleoside phosphorylase, acid phosphatase, 'X'-protein and potassium concentration only showed variation at the 'X' protein and nucleoside phosphorylase loci. Isoelectric focusing over pH range 6-8 showed 145 samples to be of haemoglobin type A and 5 type AD. The haemoglobin A type was resolved into further types by separation over pH 6.9-7.5 in Immobiline polyacrylamide gels. A 2- or 4-band pattern was present in 136 of the samples; a genetic hypothesis based on four or more different haemoglobin A variants is proposed. 14 samples had a 3-, 5- or 6-band pattern. It is assumed that these are heterozygous for a variant of the II alpha gene.     

High prevalence and genotypes of Toxoplasma gondii isolated from goats, from a retail meat store, destined for human consumption in the USA

Little information is available concerning the presence of viable Toxoplasma gondii in tissues of goats worldwide. In the present study, hearts of 234 goats obtained from a local USA grocery store were examined for T. gondii infection. Blood clot or fluid removed from each heart was tested for antibodies to T. gondii by using the modified agglutination test (MAT). Antibodies to T. gondii were found in 125 (53.4%) of 234 goats, with titers of 1:5 in 20, 1:10 in 44, 1:20 in 16, 1:40 in five, 1:160 in five, 1:320 in five, and 1:640 or higher in 30 goats. Hearts of 112 goats (46 goats <1:5, and 66 goats 1:10 or higher) were used for isolation of viable T. gondii by bioassays in mice. For bioassays, 50 g of the myocardium were digested in an acid pepsin solution and the digest inoculated into mice; the recipient mice were examined for T. gondii infection. Toxoplasma gondii was isolated from 29 goats; from hearts of one of 46 with titers of <1:5, one of nine with titers of 1:10, one of three with titers of 1:40, and 26 of 40 with titers of 1:160 or higher. Two isolates were highly virulent to outbred Swiss Webster mice; all infected mice died of toxoplasmosis, irrespective of the dose. All T. gondii isolates were subsequently grown in cell cultures. Genotyping of the 29 T. gondii isolates using 10 PCR-restriction fragment length polymorphism markers (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and Apico) from DNA obtained from cell culture grown tachyzoites revealed 12 genotypes. Nine isolates were clonal Type II lineage, four isolates had type II alleles at all loci except a type I allele at the Apico locus, and four isolates were clonal Type III. The remaining 12 strains were divided into nine atypical genotypes, including five new and four previously identified genotypes. DNA sequences of four introns (EF1, HP2, UPRT1 and UPRT7) and two genes (GRA6 and GRA7) were generated for the five new genotypes. Comparing these sequences with previously published data revealed no unique sequences in these goat strains. Taken together, these results indicate high parasite prevalence and moderate genetic diversity of T. gondii in goats, which have important implications in public health. We believe this is the first genetic analysis of T. gondii isolates from goats in the USA.     

Economic implication of diseases in goats in India with reference to implementation of a health plan calendar

The role of goats in the economy of the rural resource poor in India and economic losses due to mortality and morbidity at micro and macro level is important. Goats contribute more than 52% of households’ total income towards nutrition and food security of the family of goat keepers. The mortality and morbidity losses due to diseases in goats were estimated at field level in Mathura district of Uttar Pradesh State, India. The mortality rates for small, medium and large categories of goat keeping were 32.8, 32.1 and 15.8% in kids and 31.2, 19.9 and 14.9% in adult goats, respectively. The losses due to diseases in goats scaled at national level were estimated at Rs. 11,720 million per annum. The adoption of prophylactic and preventive measures in goats could result in a net savings of Rs. 5144 million per annum to the economy of the country. The study demonstrates a need to use available technology to prevent diseases in goats.     

Antibodies to Corynebacterium Pseudotuberculosis in Adult Goats from a Naturally Infected Herd

Serum samples taken in 3 successive years (1977, 1978 and 1979) from adult dairy goats (Norwegian breed) originating from 1 herd were examined for antibodies to Gorynebacterium pseudotuberculosis. Both bacterial agglutination test (BAT) and hemolysis inhibition test (HIT) were used. The proportion of seropositive goats increased 10–12 % during the investigation period. In 1979 all animals were seropositive to BAT and about 95 % had antihemolysins in their sera. Twenty-two of the 23 one-year old goats recruited to the herd in 1978 were seropositive. The average age-specific titres increased up to the age of 3 years, and subsequently decreased for goats aged 4–7 years. Caseous lymphadenitis is thus regarded as a chronic infection. The effect of age on the titre values was significant at the 5 % level in 1977 and 1978 when HIT was used and in 1978 when BAT was used. During the investigation period the same 36 and 40 goats were examined every year by BAT and HIT, respectively. Intermediate to high correlations between titre values for the same goats from year to year were found. Both BAT and HIT are suitable for sero-epidemiological investigations concerning infection with G. pseudotuberculosis in goats.     

Differential effects of goat browsing on herbaceous plant community in a two-phase mosaic

The impact of herbivores on herbaceous plant communities is usually attributed to direct consumption of plants. We hypothesized that goats affect herbaceous plants both directly (consumption by foraging) and indirectly, by changing environmental conditions through modification of woody plant structure. We assessed the effects of goats browsing on environmental conditions, landscape structure, and herbaceous plants to link the direct and indirect effects of goats on herbaceous communities. Our model system was the Mediterranean woodland in Mt. Carmel, Israel. This is a two-phase mosaic landscape, composed of herbaceous (open) and woody patches. We delineated 10 plots of 1000 m², goats were introduced to five plots and five plots remained without goats. We monitored plant species richness and composition in two adjacent patch types (woody and open) in each plot. For each patch type, in all plots, we collected data on environmental conditions. We analyzed landscape structure using landscape metrics derived from a high-resolution vegetation map. We found that goats modified the structure of woody plants and hence the landscape mosaic. This alteration was associated with changes in environmental conditions, with more light penetration and higher temperatures. The impact of goats on the herbaceous plant community depended on patch type. In open patches, goats affected the herbaceous community mostly by direct consumption, whereas in woody patches they affected the herbaceous community mainly by modification of abiotic conditions. Our results stress the importance of considering landscape and patch structure in analyzing the effect of herbivory on plant communities.     

Species-specific responses of N homeostasis and electrolyte handling to low N intake: a comparative physiological approach in a monogastric and a ruminant species

In our former studies low crude protein (LCP) intake influenced N homeostasis and electrolyte handling in goats. We hypothesised that due to rumino-hepatic nitrogen (N) recycling adaptation of N homeostasis and adjustment of electrolyte handling to LCP intake differs between goats and monogastric animals. Therefore, an experiment similar to that with goats was conducted with rats. Two feeding groups received a diet either containing 20 or 8 % crude protein (as fed basis) for 5 weeks and intake and excretion of N, calcium (Ca) and phosphorus (P) were determined. To detect systemic and endocrine adaptation to LCP intake plasma concentrations of urea, Ca, phosphate (Pi), insulin-like growth factor 1 (IGF-1), 1,25-dihydroxyvitamin D₃ (calcitriol), parathyroid hormone (PTH) and cross-linked telopeptide of type I collagen (CTX) were measured. Adjustment of renal electrolyte transport was assessed by detecting protein expression of key proteins of renal Pi transport. All data were compared with the data of the goat experiment. LCP intake decreased plasma urea concentration stronger in goats than in rats. In both species urinary N excretion declined, but faecal N excretion decreased in goats only. Furthermore, in goats urinary Ca excretion decreased, but in rats urinary Ca concentration increased. Decreased plasma IGF-1 and calcitriol concentrations were found in goats only. Thus, renal Ca excretion appears to be a common target in adaptation of electrolyte homeostasis in both species, but is regulated differently.     

PRNP haplotype distribution in Moroccan goats

Susceptibility/resistance to scrapie in sheep and goats is influenced by host prion protein gene ( PRNP ) genotype. In this study, we report the analysis of prion protein gene polymorphisms in 137 goats of two Moroccan populations: D'man and Chaouni. We found seven previously described amino acid polymorphisms at codons 37, 127, 137, 142, 154, 222 and 240, as well as three known silent mutations. In addition, we identified three new allelic variants: 101R and 139S in D'man goats and 145D in D'man and Chaouni individuals. The high frequency of the resistant allele 154H could offer genetic protection against the disease to the analysed animals. A total of 12 haplotypes and 28 genotypes were found, the distribution of which shows significant differences between both groups. Moreover, haplotype frequencies were compared with bibliographic data showing that the haplotype distribution of PRNP in Moroccan populations is genetically similar to Southern Italian and Greek goats.     

Biomaterial-loaded allograft threaded cage for the treatment of femoral head osteonecrosis in a goat model

The purpose of this study was to evaluate the efficacy of core decompression with a biomaterial-loaded allograft threaded cage (ATC) for the treatment of femoral head osteonecrosis in an established goat model. First, bilateral early-stage osteonecrosis was induced. After core decompression, the remaining goats were randomly divided into three groups: Group A, the goats were left without any treatment; Group B, the goats were treated with implanting a composite of autologous bone and decalcified bone matrix (DBM); Group C, the goats were treated using insertion of ATC loaded with DBM and autogenous bone graft. Then radiographic, histological and biomechanical analysis were taken in each group at 5, 10, and 20 weeks postoperation. In Group A, the classical signs of osteonecrosis of the femoral head were identified 10 weeks after the induction. Twenty weeks later, the density, surface and biomechanical stability of the femoral head were normal in Group C, while an irregular surface and an inhomogeneous microstructure or variation of density/hardness were identified in Group B. The specimens revealed a continuous trabaecular bone structure throughout the cage and extensive bone ingrowth and remodeling in Group C, while fibrous tissue was evident in Group B. Core decompression with a biomaterial loaded ATC almost uniformly delays or arrests the progression of the disease before articular collapse, and it could help to get the balance between bone resorption and new bone formation, strengthen structural mechanics of the femoral head, provide structure support of articular cartilage.     

Selection for nutrients by pregnant goats on a microphyll desert scrub

The behavioral consequences of pregnancy in goats were studied to test the hypothesis that pregnant females on rangeland select a diet richer in nutrients once the demands of gestation increase, and that nutrient content in goat diets changes with the grazing season. A total of 12 mature mixed breed goats either pregnant (n = 6) or non-pregnant (n = 6) were used during the dry period (February to May). Dietary samples obtained from the oral cavity of grazing goats (restrained with a short light rope permanently tightened around their neck) were used for chemical analyses. Across months, pregnant goats selected diets higher (P < 0.01) in crude protein (CP) than non-pregnant goats; this nutrient did not meet the requirements of late gestating goats. Pregnant goats made use of less (P < 0.01) fibrous feeds than non-pregnant goats. In order to cope with changing nutrient demands for pregnancy, goats adjusted their diet by increasing the selection of plants with 32% higher calcium content compared to forages selected by non-pregnant goats. The physiological state of goats did not alter the levels of phosphorus (P), magnesium (Mg) and sodium (Na) in their diets; these minerals were adequate to meet the demands of pregnancy. There were no effects of physiological state on concentrations of copper (Cu), zinc (Zn), manganese (Mn) and iron (Fe) in the goat diets during the dry season, with levels adequate for sustainability of pregnancy. Pregnant goats did not seek forages lower in tannins, alkaloids, saponins and terpenes. It was concluded that to cope with increasing pregnancy costs, goats adjusted their diets increasing selection of forages or plant parts with high nutritional value to maximize their net nutrient budget.     

An investigation of five genetic loci controlling polymorphic variants in the red cells of goats

Results of a joint study carried out in South Africa and England to search for new genetic markers in the blood of goats are presented. Haemoglobin (Hb) phenotypes were reinvestigated with the technique of isoelectric focusing; frequencies in different goat breeds are given. Anaemic Hb type A, AB and B goats all produced a Hb C with an identical electrophoretic pattern. All goats tested had identical carbonic anhydrase (CA) types, but showed polymorphism of 'X' protein. Preliminary results indicated that nucleoside phosphorylase (NP) may be polymorphic.     

Immunization against Rumen Methanogenesis by Vaccination with a New Recombinant Protein

Vaccination through recombinant proteins against rumen methanogenesis provides a mitigation approach to reduce enteric methane (CH₄) emissions in ruminants. The objective of present study was to evaluate the in vivo efficacy of a new vaccine candidate protein (EhaF) on methanogenesis and microbial population in the rumen of goats. We amplified the gene mru 1407 encoding protein EhaF using fresh rumen fluid samples of mature goats and successfully expressed recombinant protein (EhaF) in Escherichia coli Rosetta. This product was evaluated using 12 mature goats with half for control and other half injected with 400ug/goat the purified recombinant protein in day 1 and two subsequent booster immunizations in day 35 and 49. All measurements were undertaken from 63 to 68 days after the initial vaccination, with CH₄ emissions determined using respiration calorimeter chambers. The results showed that the vaccination caused intensive immune responses in serum and saliva, although it had no significant effect on total enteric CH₄ emissions and methanogen population in the rumen, when compared with the control goats. However, the vaccination altered the composition of rumen bacteria, especially the abundance of main phylum Firmicutes and genus Prevotella. The results indicate that protein EhaF might not be an effective vaccine to reduce enteric CH4 emissions but our vaccine have potential to influence the rumen ecosystem of goats.     

An investigation of five genetic loci controlling polymorphic variants in the red cells of goats*

Results of a joint study carried out in South Africa and England to search for new genetic markers in the blood of goats are presented. Haemoglobin (Hb) phenotypes were reinvestigated with the technique of isoelectric focusing; frequencies in different goat breeds are given. Anaemic Hb type A, AB and B goats all produced a Hb C with an identical electrophoretic pattern. All goats tested had identical carbonic anhydrase (CA) types, but showed polymorphism of ‘X’ protein. Preliminary results indicated that nucleoside phosphorylase (NP) may be polymorphic.     

Prospects for applying breeding for resistance to control scrapie in goats: The current situation in Italy

Genetic selection has been used to control transmissible spongiform encephalopathies (TSEs) in sheep populations based on the association between PRNP polymorphisms and resistance to scrapie. In goats even if a protective role has been suggested for several polymorphisms (I142M, H143R, N146D/S, R154H, R211Q, Q222K) by different European studies, a similar, univocal association has not been proved so far.The aim of this paper was to identify target polymorphisms in goats and their potential applicability in a selection plan in Italy. For this purpose, the existing genetic data on modulating resistance to classical and atypical scrapie in goats in this country will be used as starting point.Two Italian case–control studies concluded that the polymorphism at codon 222 (from glutamine to lysine Q/K) is important in influencing the susceptibility of goats to classical scrapie. Moreover, goats are susceptible to an unusual form of scrapie, named Nor98, and the H154 mutation was shown to be statistically associated with this disease in goats in an Italian case–control study. Currently, a strategy based on killing goats carrying the H154 mutation is being applied to manage atypical scrapie outbreaks in Italy.The current situation in Italy bodes well for the applicability of breeding plans based on the K222 mutation; data from independent studies on the role of K222 as a protective or even a resistance factor and its frequency in several Italian breeds are available. In the near future, as new data on K222 will be reported, testing the application of selective culling in classical scrapie goat outbreaks may become feasible.     

Gynecological examination and pregnancy diagnosis in small ruminants using bimanual palpation technique: a review

A palpation technique using both hands was developed by the author and used for examination of internal reproductive organs, pregnancy diagnosis, and assessment of approximate stages of gestation in small ruminants. The study was conducted in 4 stages on 87 female goats and 30 slaughterhouse source ewes First, 20 doelings and 15 does with no recent history of insemination were examined by two hand method for palpability and structural integrity of internal reproductive organs. Next 52 goats (28 doelings and 24 does) were examined at 28 to 30 d post insemination for pregnancy. Among those diagnosed pregnant, 20 goats were examined at 15 d intervals to assess the palpable changes of pregnancy. Preslaughter palpation followed by post-slaughter verification of the findings were performed in 30 ewes. The two hand method was effective for palpating the reproductive tract in the nonpregnant goats irrespective of parity status. Gross palpation of the ovaries was possible in 83% of the goats. Of the 52 goats examined for pregnancy at 28 to 30 d, 29 (56%) had clear distension of uterus while 23 (44%) did not. The results were confirmed by kidding date or returning to service. Changes of the reproductive tract were monitored in 20 goats at biweekly intervals and the findings categorized by the stage of gestation. Post slaughter verification of preslaughter findings based on two handed palpation indicates that this technique can be used for early pregnancy diagnosis and assessment of the stage of gestation in goats and ewes.     

Goat domestication and breeding: a jigsaw of historical,biological and molecular data with missing pieces

Domestic goats (Capra hircus) are spread across the five continents with a census of 1 billion individuals. The worldwide population of goats descends from a limited number of bezoars (Capra aegagrus) domesticated 10 000 YBP (years before the present) in the Fertile Crescent. The extraordinary adaptability and hardiness of goats favoured their rapid spread over the Old World, reaching the Iberian Peninsula and Southern Africa 7000 YBP and 2000 YBP respectively. Molecular studies have revealed one major mitochondrial haplogroup A and five less frequent haplogroups B, C, D, F and G. Moreover, the analysis of autosomal and Y‐chromosome markers has evidenced an appreciable geographic differentiation. The implementation of new molecular technologies, such as whole‐genome sequencing and genome‐wide genotyping, allows for the exploration of caprine diversity at an unprecedented scale, thus providing new insights into the evolutionary history of goats. In spite of a number of pitfalls, the characterization of the functional elements of the goat genome is expected to play a key role in understanding the genetic determination of economically relevant traits. Genomic selection and genome editing also hold great potential, particularly for improving traits that cannot be modified easily by traditional selection.     

Foraging behaviour of the newly introduced Boer goat breed in a Mediterranean woodland: A research observation

Brush encroachment is reducing pasture and amenity values of rangelands in the upper Galilee, Israel. Local Mamber goats are efficient at preventing brush encroachment, but their low prolificacy and slow growth of their kids prevent profitable farming. Boer goats from southern Africa are deemed to be prolific and rapidly growing, but their ability to exploit Mediterranean woodland and scrubland in Israel was unknown. Simultaneous observations (n = 604) on the eating behaviour of Boer goats imported from Namibia and of local Mamber goats were recorded from May 1997 to January 1998. Socialization between breeds was prevented by keeping them in distinct flocks in two similar paddocks. Boer goats spent less time than Mamber goats in grazing herbaceous species (22 and 44%, respectively), which suggests that Boers would be potentially less competitive to cattle than Mambers in mixed grazing systems. Boers allocated 90% of their eating time to eight species, compared with only four species for Mambers. Browse use on the main encroaching species differed between goat breeds: Mambers spent more time browsing on Sarcopoterium spinosum whereas Boers spent more time on Cistus creticus and Cistus salvifolius. No difference between breeds was observed with regard to Calycotome villosa, the main encroaching species on the range. Boers exhibited a 10% lower bite rate than Mambers, but no difference between breeds was noted in their mass per bite of browse species. Results of this study suggest that Boer goats have the potential to control brush encroachment more than Mamber goats, especially when they are associated with cattle.