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The heritability and the phenotypic and genetic correlations of down weight (DW), down fibre diameter (DFD), and coefficient of variation of the down fibre diameter (CVDFD) of Chinese Alashan Left Banner White Cashmere goat were estimated on 1375 one-year-old animals, born in 2009, 2011 and 2013 and bred at the Station for Livestock Improvement of Alashan (Left Banner, Inner Mongolia, P.R. China). For all traits, significant effects were for sex, cohort and sex–cohort interaction (p

Two new Euplotes species have been isolated from cold shallow sandy sediments of the extreme Southern Chilean coasts: Euplotes foissneri sp. nov., from a low-salinity site at Puerto Natales on the Pacific coast, and Euplotes warreni sp. nov., from a marine site at Punta Arenas on the Atlantic coast. Euplotes foissneri has a medium body size (53×36 µm in vivo), a dorsal surface marked by six prominent ridges, a double dargyrome, six dorsal and two ventrolateral kineties, a buccal field extending to about 3/4 of the body length, an adoral zone composed of 28–32 membranelles, and nine fronto-ventral, five transverse and two or three caudal cirri. The bulky, hook-, horseshoe- or 3-shaped macronucleus is associated with one sub-spherical micronucleus. The central body region hosts taxonomically unidentified endosymbiotic eubacteria. Euplotes warreni has a small body size (39×27 µm in vivo), a smooth dorsal surface marked by three deep grooves, a double dargyrome, four dorsal and two ventrolateral kineties, a buccal field extending to about 2/3 of the body length, an adoral zone composed of 23–25 adoral membranelles, and nine fronto-ventral, five transverse and three caudal cirri. The macronucleus is hook- or C-shaped and associated with one spherical micronucleus. Endosymbiotic bacteria belonging to the genus Francisella reside preferentially in the anterior cell region. Both species lack the fronto-ventral cirrus numbered ‘V/2’, whereby their cirrotype-9 conforms to the so-called ‘pattern I’, which is the basic distinctive trait of the genus Euplotopsis Borror and Hill, 1995. Phylogenetic analyses of small subunit rRNA gene sequences, however, classify E. warreni into its own early branching clade and E. foissneri into a late branching clade. This indicates a polyphyletic nature and taxonomic inconsistency of the genus Euplotopsis, which was erected to include Euplotes species with cirrotype-9 pattern I.

The most precious textile fibre produced by the Chinese Alashan Left Banner White Cashmere goat is known as Baby Cashmere which is the hair produced during their first 6 months of life. This fleece is 1 μm finer than regular cashmere and nowadays is harvested by shearing the kids at 6 months of age. Seasonal variation in follicle activity was studied in the skin of eleven female goat kids born on January 2010 in the Station for Livestock Improvement of Alashan, Left Banner, Inner Mongolia (P.R. China) (latitude 38° 24′ N and longitude 104° 42′ E). Nine consecutive monthly skin biopsies (from March until November) were used to monitoring the number of active primary and secondary follicle and the number of inactive secondary follicles. The recorded data were used to calculate the percentage of inactive secondary follicles and the ratio of secondary to primary follicles. The number of active primary follicles showed low variability across the sampling period. On the contrary, the number of active secondary follicles decreased from March until June and then sharp increased until its maximum value in August when the kids were 7 months old. The percentage of inactive secondary follicles progressively increased from April to its maximum values in June when the goats were 5–6 months old. Then, the percentage was strongly reduced from July until October and finally has risen in the last observation in November. The ratio of secondary to primary follicle started to decrease from March and remained to its lower values until July when the kids were 6 months old. From July the ratio dramatically increased and gained its maximum values in August when the goats are 7 months old and finally slowly decreased until the last observation in November. The study suggests that goats born in January could shed the baby fiber between July and August, however, trials of combing are needed to assess whether or not the fleeces are actually shed.

The Chinese Alashan Left Banner White Cashmere goat is a subpopulation of the Inner Mongolian Cashmere goat which produced a very fine cashmere. In the last years, textile industry addressed particular attention in the cashmere produced by the youngest cashmere goats especially on changes in fleece characteristics during the first year of life. This study described the coat development in Chinese Alashan Left Banner White Cashmere goat kids in the first year of life, from three months of age until the first combing season. Twelve does born on January 2009 were selected at random from the herd located in the Station for Livestock Improvement of Alashan. Fleece sampling started at April 2009 and was repeated monthly till February 2010. The analysis of variance showed that the length of down hair and guard hair, the cashmere diameter and coefficient of variation of diameter were significantly influenced by the age. Furthermore, the study revealed that the kids bear the down hair from birth. The length of the down hair increased for the first five months of life until the first moult in June-July at around 5–6 months of age. On the contrary, no shedding of the guard hair was observed. In fact, the guard hair of the kids continued to increase in length until the goats were 13 months old. These results suggest an asynchronous pattern of moulting of the birth double-coat. Moreover, the baby down hair shedded during the first moult was finest (on average

The objective of this trial was to determine if an anticipated first shearing at 10 months of age affects skin characteristics and fibre quality in alpacas in order to assess the possibility of practice two different shearings over a period of 16 months in the animals destined for slaughter. Twenty alpaca Huacaya (10 females and 10 males) were randomly assigned to two groups named Group S and Group NS. Group S alpacas were sheared in December at the age of 10 months, when fibre had reached the length of 12.78 cm. Group NS alpacas were not sheared and their fibre length in December at the age of 10 months was of 13.11 cm. Skin biopsies and fleece were sampled from each animals at 10, 11, 12, and 16 months of age. The recorded data were used to calculate the fibre diameter, the fibre length, the percentage of active secondary follicles and the ratio of secondary to primary follicles. Data were analysed as a split-plot design with the shearing effect as whole-plot, the age effect as subplot and the animals as replication term in testing the shearing effect. Fibre diameter, percentage of active secondary follicles and S/P ratio showed no statistically significant differences between treatment groups and age. Significant different (P < 0.05) between treatment groups and age were observed only for the fibre length. At the end of the trial the fibre length was of 7.71 cm and 17.4 cm for the sheared and non-sheared animals respectively. This implies that during the six months following the shearing of 10 months old alpacas from the Group S (from January to June), the fleece length had increased by 7.71 cm and 4.29 cm in sheared and non-sheared animals respectively. In other words, the fibre length in sheared alpacas showed an increase compared to the fibre from non-sheared one of 3.42 cm (+79.7 %). This result showed that shearing increased fibre growth in yearling alpacas. Based on our trial, breeders could practice two different shearings, first at 10 months of age and later at 16 months of age right before slaughtering, in order to harvesting two batches of fine kid fleece with an average length of 12.78 cm and 7.71 cm.

An experimental trial of the segregation of white vs. pigmented and black vs. brown colours in alpacas was conducted at the Peruvian INIA Quimsachata Experimental Station. One hundred and forty five offspring were born from the following matings: 4 white sires × 36 white dams, 4 white sires × 39 pigmented dams, and 9 pigmented sires × 70 pigmented dams. Among these last matings were, 4 black sires × 25 black dams, 2 black sires × 20 brown dams, and 3 brown sires × 25 brown dams. Statistical tests validate that the inheritance of white is due to a single gene which is dominant over pigmentation, without any modifying effect and independent of segregation of black and brown patterns. However, the evidence does not support a simple dominant inheritance of the black vs. brown.

Fourteen female Alashan white cashmere goats were investigated for fibre finesses (diameter) and coefficient of variation of fineness (CV). The investigation focused on the same animals combed at 1, 3 and 4 years of age and fibres were collected from 10 different body areas. A statistically significant effect was observed for both year of collection and body areas. The present paper suggests that the fibres of one-year old animals should be kept distinct from older ones, likewise fibres from upper part of the body should be separated from the others. © 2016 Published by Elsevier B.V.

This study aimed to evaluate the effect of four non-genetic factors (sex, coat colour, competition judges, type of trial) on the five hunting traits (search, approach, tracking of prey, standstill barking and physical skills) used to estimate the aptitude for wild boar hunt in Italian Maremma Scent Hound. A total of 1147 dogs (734 males, 399 females, and 14 not sexed dogs) were evaluated in competitions held in North-Central Italy, from 2010 to 2011. Dogs were tested as individuals, pairs and packs. Coat colour had no effect on the five tested traits. A significant difference (p

The effects of different concentrate levels in the diet on plasma 3-3′-5-triiodothyronine (T3) and thyroxine (T4) concentrations in does of different physiological conditions were investigated. Blood samples were taken starting in autumn from 20 goats fed hay ad libitum, during the dry period (30 days and 3 days prior to the synchronized oestrus; D1 and D2, respectively), pregnancy (week 13, week 17 and week 21 of pregnancy; P1, P2 and P3, respectively) and lactation (5 weeks and 13 weeks following parturition; L1 and L2, respectively). The control group (C, n = 10) was fed either 0.2 (in periods D1, D2 and P1) or 0.4 kg maize grain(head per day) (in P2, P3, L1 and L2). The high energy diet group (H, n = 10) was fed either 0.4 (in D1, D2 and P1) or 0.7 kg maize grain(head day) (in P2, P3, L1 and L2). Plasma total T3 concentrations were affected only by the sampling period, being significantly higher in the P1 period (0.96 ± 0.05 ng/ml) than in the dry period (0.72 ± 0.04 ng/ml) and in P3 (0.70 ± 0.02 ng/ml). In the C goats the plasma T4 concentration recorded in the P1 (65.6 ± 2.6 ng/ml) and L1 (62.8 ± 5.2 ng/ml) periods was significantly higher than that in P3 (40.2 ± 3 ng/ml). The variation in plasma T4 concentration in the H does was not significantly different throughout the different physiological stages. The decrease in plasma T3 and T4 concentrations in the second half of pregnancy in the H goats was delayed by 1 month. In addition, during the last 2 months of pregnancy, the higher concentrate diet induced higher plasma T3 (0.92 ± 0.06 ng/ml) and T4 (67.2 ± 6.6 ng/ml) concentrations when compared to the C (0.76 ± 0.04 and 45.1 ± 3.2 ng/ml for T3 and T4, respectively) group. The effect of energy intake on plasma thyroid hormone secretion during late pregnancy could be explained by a negative energy balance that usually occurs during this period. During lactation the higher energy diet had no significant effect on milk yield nor on the plasma thyroid hormone concentrations. The concentrate level of the C diet seemed to be sufficient to meet the energy requirements for milk production in these goats, as indicated also by the lack of body weight and body condition score (BCS) changes during lactation. The results of the present study highlight the relationships between thyroid activity and energy balance in the goat species. Circulating thyroid hormones represent a relevant metabolic index of the animals’ nutritional state.

Secondary metabolites present in the neem tree ( Azadirachta indica A. Juss, Meliaceae), exhibit a wide range of biological activities in insects. However, few studies have been undertaken to assess the potential of neem products as insecticides for the control of ectoparasites of domestic animals. This study was undertaken to estimate the efficacy of Neem Azal ® , an azadirachtin-rich extract of neem seeds, in controlling Damalinia limbata (Phthiraptera) louse infestation of angora goats. The study was conducted on a fibre animal farm situated in Central Italy. Groups of 11–12 goats were treated with Neem Azal ® at an azadirachtin concentration of 650 ppm or 125 ppm, with Neguvon ® or were left untreated. Their louse burden was assessed fortnightly to monthly for 22 weeks. A reduction in louse densities of 76–96% was observed from week 2 to week 18 after treatment with the neem solution containing azadirachtin at a concentration of 650 ppm. At the lower test concentration (125 ppm) a reduction of 60–92% could be recorded from week 2 to week 14. Neem Azal ® was found to reduce the survival of both adult and nymph stages of D. limbata and to interfere with oviposition and oogenesis of female lice. A decrease in oviposition was observed in neem exposed female lice and the examination of their ovaries revealed morphological alterations in both vitellogenic and previtellogenic ovarioles at the follicular and germinal level. Since neem compounds target different life stages and physiological processes of D. limbata, the development of insecticide resistance by biting lice exposed to neem-based insecticides appears unlikely. For this reason and for its prolonged activity, which in principle allows angora goats to be protected for a large part of the mohair production cycle, neem-based insecticides may have a potential interest for mohair producing breeders.

Ciliate diversity was investigated in situ in freshwater ecosystems of the maritime (South Shetland Islands, mainly Livingston Island, 63°S) and continental Antarctic (Victoria Land, 75°S), and the High Arctic (Svalbard, 79°N). In total, 334 species from 117 genera were identified in both polar regions, i.e. 210 spp. (98 genera) in the Arctic, 120 spp. (73 genera) in the maritime and 59 spp. (41 genera) in the continental Antarctic. Forty-four species (13% of all species) were common to both Arctic and Antarctic freshwater bodies and 19 spp. to both Antarctic areas (12% of all species). Many taxa are cosmopolitans but some, e.g. Stentor and Metopus spp., are not, and over 20% of the taxa found in any one of the three areas are new to science. Cluster analysis revealed that species similarity between different biotopes (soil, moss) within a study area was higher than between similar biotopes in different regions. Distinct differences in the species composition of freshwater and terrestrial communities indicate that most limnetic ciliates are not ubiquitously distributed. These observations and the low congruence in species composition between both polar areas, within Antarctica and between high- and temperate-latitude water bodies, respectively, suggest that long-distance dispersal of limnetic ciliates is restricted and that some species have a limited geographical distribution.

A new species of Aspidisca, Aspidisca terranovae sp. n., was collected from sea ice and sand sediments of Terra Nova Bay (Ross Sea, Antarctica). It is characterized by: seven frontoventral cirri showing a ‘polystyle‐arrangement’, five transverse cirri, a prominent peristomial spur, and a smooth dorsal surface carrying four kineties.

Summary Intramacronuclear inclusions, apparently of proteinaceous nature and of the “sphere” type, have been detected in two species of Euplotes , E. focardii and E. nobilii , collected from the marine benthos of the Ross Sea (Antarctica) and reproducing in the laboratory at 4 °C. In E. focardii , they are up to 5 μm in diameter and arranged medially along the macronucleus, while in E. nobilii they are smaller and arranged more randomly. Associated with these inclusions there are normal chromatin bodies, but no apparent nucleoli. It was suggested that these inclusions essentially consist of protein moieties of modified nucleoli which are depleted of most (or all) RNA, or contain dispersed, yet functional, RNA areas.

The amount of melanin pigments was investigated in 95 Peruvian alpaca, representative of six different fleece colours, by means of spectrophotometric assays: SpEM (Spectrophoto­metric Eumelanin), SpPM (Spectrophotometric Pheomelanin), SpASM (Spectrophotometric Alkali Soluble Melanin), and SpTM (Spectro­photometric Total Melanin). It was found that these melanin pigments were suitable for identifying three homogeneous groups, each consisting of two closely related colours. A low, an intermediate, and a high amount of SpASM, SpTM, and SpPM characterize pinkish grey and light reddish brown, brown and reddish brown, dark reddish brown and black fleeces, respectively. SpEM and SpTM provide a further split within this latter group; higher concentrations of these pigments distinguish black fleece from dark reddish brown.

The Suri/Huacaya phenotype inheritance in alpaca was tested on two independent Peruvian sources of records: the Registry of Mallkini farm (588 offspring by Suri sire × Suri dam from 62 paternal half sib families, and 2,126 offspring by Huacaya sire × Huacaya dam from 177 paternal half sib families) and the results of the Quimsachata INIA ILPA Puno experimental trial (two reciprocal experimental test-crosses, involving a total of 17 unrelated males and 149 unrelated females). The data support a genetic model in which two linked loci must simultaneously be homozygous for recessive alleles in order to produce the Huacaya phenotype. The estimated recombination rate between these loci was 0.099 (95% C.L. = 0.029-0.204). The birth of 3 Suri offspring from Huacaya × Huacaya mating is explained by a new dominant mutation on some germinal lines of Huacaya animals. The direct mutation rate can be estimated at 0.0014.

Forty alpaca kids, comprising 20 huacaya and 20 suri, and 20 llama “chaku” (or woolly type), were chosen for a comparative investigation of the fiber and cuticular attributes based on fiber diameter, number of cuticular scales per 100 µm of fiber length, and scale height. Out of the three parameters investigated, the number of cuticular scales proved to be a valid diagnostic trait in distinguishing suri fleece from both huacaya and llama fleeces. A further characterization of the suri fleece was obtained by considering the frequency distribution of both fiber diameter and number of cuticular scale classes. The suri fleece was clearly different from both the huacaya and llama in that it possessed the highest percentage of fibers with less than eight scales, the lowest percentage of fibers with more than nine scales, along with the lowest percentage of fibers with a diameter of more than 35 µm. The validity of these classification criteria was fully supported by a classification discriminant analysis based on the jointed investigation of the data related to scale and diameter frequency classes, whose output was a 100% correct classification of the suri specimens along with an 85.7% and 71.4% of cases correctly classified in huacaya and llama, respectively.

One hundred twenty non-autogamous wild-type strains of Euplotes crassus, collected over seven years, mainly from the Mediterranean coasts, were investigated for their mating interactions. The strains were mixed pair-wise and data from mating reactions were evaluated and organized by means of a specially constructed computer program. The program identified 38 strains with distinctive mating patterns which could be clustered in nine clumps, all of which were connected either directly or indirectly. Thus, all these strains appeared to be components of the same gene pool, even though direct genetic exchange between strains was not possible in every combination. Subsequently, the 38 strains were subjected to cytometric analysis and scored for zymic variations resulting from electrophoretic patterns of five enzyme systems (acid phosphatases, amylases, malic dehydrogenase, malic enzyme, and tetrazolium oxidases) of proved diagnostic value in the identification of Euplotes species. No significant discontinuities correlated with mating patterns was apparent from these analyses. It was concluded that the E. crassus strains analyzed are not properly divided in sibling species and it was consistently suggested to avoid a genetic partitioning of ciliate species endowed with high multiple mating type systems, in which the sets of wild strains brought under investigation with difficulty represent the natural dimensions of the species.

Coat colour heredity patterns, from crosses and paternal backcrosses involving black and brown spotted Merino rams and full white Merino ewes, were investigated through segregation analyses. Statistical tests validate the hypothesis of a dominance with complete penetrance of: (i) full white over pigmented, (ii) black over brown, and (iii) uniform over spotted pattern, as well as, of a dominant epistasis of white/pigmented over both black/brown and uniform/spotted. Besides, the pigmented pattern segregations are independent of the sex of the individuals. These results largely agree with those already reported in literature, yet they are in contrast with the hypothesis of a full white obtainable only on a pheomelanic background coupled with a modifying effect due to the spotted gene. Moreover, epistatic effects of white have been never described.

A new species of Uronychia, U. antarctica, was collected from marine sand sediments of Terra Nova Bay (Ross Sea, Antarctica) and studied by means of scanning electron microscopical observations. It is a medium‐sized ciliate (54 × 45 μm) characterized by an anterior set of nine adoral ciliary membranelles, and a mid‐dorsal kinety (or kinety No. 4) which terminates at the level of the cell equator and contains no more than 23 bristle cilia.

Ciliate diversity was investigated in situ in freshwater ecosystems of the maritime (South Shetland Islands, mainly Livingston Island, 63 degrees S) and continental Antarctic (Victoria Land, 75 degrees S), and the High Arctic (Svalbard, 79 degrees N). In total, 334 species from 117 genera were identified in both polar regions, i.e. 210 spp. (98 genera) in the Arctic, 120 spp. (73 genera) in the maritime and 59 spp. (41 genera) in the continental Antarctic. Forty-four species (13% of all species) were common to both Arctic and Antarctic freshwater bodies and 19 spp. to both Antarctic areas (12% of all species). Many taxa are cosmopolitans but some, e.g. Stentor and Metopus spp., are not, and over 20% of the taxa found in any one of the three areas are new to science. Cluster analysis revealed that species similarity between different biotopes (soil, moss) within a study area was higher than between similar biotopes in different regions. Distinct differences in the species composition of freshwater and terrestrial communities indicate that most limnetic ciliates are not ubiquitously distributed. These observations and the low congruence in species composition between both polar areas, within Antarctica and between high- and temperate-latitude water bodies, respectively, suggest that long-distance dispersal of limnetic ciliates is restricted and that some species have a limited geographical distribution.

Fifteen alpaca kids, comprising 10 huacaya and 5 suri, and 10 llama kids of chaku type, born on January 1998 at the “Alpaquero” Developing Centre of Toccra, located in the Arequipa Plateau, Caylloma Province (Peru), were chosen for determining the age at which all the secondary follicles reach the maturity, as well as for comparing the skin follicular structure and activity among these different types of Peruvian camelids. Skin biopsies were taken at 2, 4, 6, and 10 months of age in order to monitor four follicular parameters: i) follicular density (FD), ii) ratio of secondary to primary follicles (S/P), iii) percentage of medullated secondary fibres (PMS); and iv) percentage of active secondary follicles (PAS). As a general trend, three parameters, i.e., FD, PMS, and PAS, reached maximum values at the 2nd month, minimum values at the 6th month (i.e., during the winter season) and increased again until observations stopped at month 10. A slightly different trend was shown by the S/P parameter which, after having gained its maximum value at month 4, progressively decreased until the end of the observations. It is concluded that the South American camelids here investigated, gained a complete and mature skin follicle apparatus at an early age and, hence, producers should practice an anticipated first shearing.

Wild strains of Euplotes euryhalinus, E. focardii, and E. nobilii, three Antarctic species originally described on morphological grounds, were analyzed for five enzyme systems (i.e., amylases, acid phosphatases, tetrazolium oxydases, malic dehydrogenases, and malic enzyme) of proven diagnostic value for the systematics of Euplotes species. The electrophoretic patterns were all effective for discriminating strains of one species from those of another; in particular those of amylases, acid phospatases, and tetrazolium oxidases showed sharp inter‐species differences and no appreciable intra‐species variations. These results provided further evidence of the species status of Euplotes euryhalinus, E. focardii, and E. nobilii.

Summary The structural organization of the dorsal cell surface was studied in parallel with the pattern of the dorsal argyrome in Euplotes bisulcatus and other related species of Euplotes . Evidence is provided for the involvement of cortical alveoli of similar width in the construction of double argyromes. Argyromes usually described as double- patella are shown to result from the presence of longitudinal ridges of varying shapes on the dorsal cell surface, which strongly affect the appearance of the argyrome under light microscopy. On a completely different experimental basis, this work supports the suggestion by Gates and Curds [5] that the typology of the dorsal argyrome of Euplotes should be restricted only to the basic types single, double, and multiple. In addition, it reiterates the diagnostic value of cortical sculpturing in Euplotes taxonomy.

Four different tubulin genes were identified in the somatic nucleus (macronucleus) of Euplotes focardii, a strictly cold-adapted, Antarctic ciliate: one of 1,800 bp for alpha-tubulin and three of 2,150, 1,900, and 1,600 bp, respectively, for beta-tubulin. Preliminarily analysed for restriction fragment length polymorphisms, these genes showed remarkable differences in organisation from tubulin genes of other ciliates which live in temperate areas and were analysed in parallel with E. focardii. The complete coding sequence of the 1,600 bp beta-tubulin gene was then determined and shown to contain unique structural features of potential importance for E. focardii microtubule organization and activity. Of eight unique substitutions detected, seven were concentrated in the large amino terminal domain of the molecule that directly interacts with the carboxy terminal region of alpha-tubulin for heterodimer formation. Sequence analysis of the cloned gene revealed, in addition, a potential new exception in the use of the genetic code by ciliates. A TAG codon was aligned in correspondence with Trp-21 which is strictly conserved in every tubulin sequence so far determined.

Euplotes focardii, a ciliate species recently collected from sand sediments of Terra Nova Bay (Ross Sea, Antarctica) reproduced in the laboratory with a duplication time of approximately 72 h, at 4°C. Strains representative of two different mating types were identified and mixed together to produce mating pairs. These showed traits rather unusual for Euplotes species. The two pair members remained united for at least 8–10 days. However, only one carried out fertilization and was able to give rise to a new clone of vegetative cells; the other underwent cell body shrinking after 4–5 days of union, lost the locomotory ciliary apparatus, and eventually died. By analyses of mating pairs formed in mixtures of cell samples cytologically distinct from each other, it was ascertained that the different cell behavior is strain-specific.

Background Genetic improvement of fibre-producing animal species has often induced transition from double coated to single coated fleece, accompanied by dramatic changes in skin follicles and hair composition, likely implying variation at multiple loci. Huacaya, the more common fleece phenotype in alpaca (Vicugna pacos), is characterized by a thick dense coat growing perpendicularly from the body, whereas the alternative rare and more prized single-coated Suri phenotype is distinguished by long silky fibre that grows parallel to the body and hangs in separate, distinctive pencil locks. A single-locus genetic model has been proposed for the Suri-Huacaya phenotype, where Huacaya is recessive. Results Two reciprocal experimental test-crosses (Suri × Huacaya) were carried out, involving a total of 17 unrelated males and 149 unrelated females. An additional dataset of 587 offspring of Suri × Suri crosses was analyzed. Segregation ratios, population genotype frequencies, and/or recombination fraction under different genetic models were estimated by maximum likelihood. The single locus model for the Suri/Huacaya phenotype was rejected. In addition, we present two unexpected observations: 1) a large proportion (about 3/4) of the Suri animals are segregating (with at least one Huacaya offspring), even in breeding conditions where the Huacaya trait would have been almost eliminated; 2) a model with two different values of the segregation ratio fit the data significantly better than a model with a single parameter. Conclusions The data support a genetic model in which two linked loci must simultaneously be homozygous for recessive alleles in order to produce the Huacaya phenotype. The estimated recombination rate between these loci was 0.099 (95% C.L. = 0.029-0.204). Our genetic analysis may be useful for other species whose breeding system produces mainly half-sib families.

Specimens of Euplotes were collected from Ross Sea (Antarctica), allowed to multiply in the laboratory, and taxonomically studied on the basis of classical diagnostic traits as seen under the optical and scanning electron microscope. They were assigned to three different morphospecies, all characterized by a dorsal silver-line system of the “double” type and a set of 10 fronto-ventral cirri. Two morphospecies were identified as new and named E. nobilii and E. euryhalinus; one was judged reconcilable with E. rariseta.

SERRANO, S., SOLA, A. , GUINEA, . , ARREGUI, L., and FERNANDEZ-GALIANO, D. 1992. Cytoskeleton of Euplores focardii: morphology and morphogenesis. Can. J . Zool . 70: 2088 2094. New data are given about the infraciliature, cytoskeleton, and morphogenesis during cell division in Euplores focardii. Our observations indicate slight variability in the dorsal and ventral infraciliary pattern. The oral infraciliature is composed of a paroral complex formed by 29-34 oblique rows of kinetosomes and an adoral zone of membranelles in which three parts can be distinguished according to the number of rows and the infraciliary composition of the paramembranelles. Besides the complex microtubular cytoskeleton connected with the dorsal and ventral somatic infraciliatures, characteristic of the genus Euplores, we observe two argentophilic zones in the anterior zone of cirrus 6 and between the posterior part of the paroral complex and the adoral zone of membranelles. The process of cell division is generally similar to that described in other species of Euplores, but the somatic origin of cirrus 1 and the origin of the left marginal cirri from a single primordium should be noted. Finally, 1n E. focardii we observe the development of systems of microtubular bundles, which are probably connected with the movements of the ventral cirri during morphogenesis.

Zoothamnium intermedium was found attached to the exoskeleton of planktonic crustaceans, most of which were copepods Acartia clausi. It formed branching colonies that consisted of zooids characterized by: 1) a bell‐like shape; 2) peristomial cilia that formed a single haplokinety raised above a double polykinety; and 3) unbranched annular striae, regularly distanced from each other by about 0.5 μm, around the zooid circumference. Fully developed colonies contained also several roundish zooids that were identified as potential motile stages. In addition to colony members, free‐swimming dimorphic individuals were also occasionally observed: one type showed long trochal cilia and a scopula with a central area containing numerous protuberances; the other was characterized by short, stumpy cilia and a scopula endowed with a central finger‐like process surrounded by a pleated wrap. These free‐swimming individuals were tentatively identified as the microgamont and telotroch stage of Zoothamnium intermed...

An epizoic colonial peritrich, Zoothamnium intermedium Precht, collected from the lagoon Valle Fossa di Porto (Ferrara, Italy), is described on the basis of light and scanning electron microscope observations. It was found on the copepods Acartia clausi, A. latist‐tosa, Calanipeda aquaedulcis and zoeae of the shrimp Hippolyte longiros‐tris. In A. clausi, which was the most abundant species of the Zooplankton community, Z. intermedium was distributed over the whole body surface of 99.3% of specimens. Numerous rod‐shaped bacteria were found in association with the attachment sites of Z. intermedium.

A population of Euplotes collected from the mouths of the Rhone was assigned to the morphospecies E. charon. The 27 strains established in the laboratory were found capable of producing protective cysts in response to environmental salinities exceeding 502. and, with the exception of two, all of them formed mating pairs. Mating interactions appeared to be controlled by a system of multiple mating types, probably inherited via alleles condominant at the genetic locus mat. Cells in the G1 cell‐cycle stage, which occupies 62% of the generation time, as well as cells in the S stage could mate. Mating was followed by an unusually long period of immaturity of 120–180 fissions. In the conjugants, the micronucleus performed four divisions, one preliminary and three pregamic; the macronucleus persisted unchanged. Cytological observations suggested that the two gamete nuclei derive from different products of the preliminary micronuclear mitosis. The synkaryon regularly performed three metagamic divisions and, in th...

In an attempt to solve the ambiguity in the taxonomy of the Euplotes crassus, minuta, and vannus group, 19 strains were tested for mating interactions, electrophoresed for isozymic variations, and analyzed by multivariate morphometrics of the conventional diagnostic traits. The overall results supported the validity of the three named species. Inter-specific mating occurred only in a few crassus x vannus strain combinations and was usually inviable. Isozymic variations, in particular of amylases, malic enzyme, and malic dehydrogenase, were very restricted within conspecific strains and were great between non-conspecifics. The species ascertainment of the strains was possible on the basis of clustering and principal component analyses of morphological measures.