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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.

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.

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.