Effect of feeding by the western conifer seed bug, Leptoglossus occidentalis, on the major storage reserves of developing seeds and on seedling vigor of Douglas-fir

The impact of feeding by the western conifer seed bug (Leptoglossus occidentalis Heidemann) on storage reserves of developing seeds of Douglas-fir (Pseudostuga menziesii (Mirb.) Franco) was studied by caging nymphal and adult seed bugs on cones during late-season development, and nymphs on cones during early, mid- and late-season development. Analysis of the major storage reserves of partially damaged seeds revealed that late-season feeding by each life stage and feeding by nymphs at all three stages of cone development significantly reduced the amounts of lipid and buffer-insoluble (crystalloid) protein in seeds at harvest by up to 78 and 97%, respectively. Seeds showing light to moderate damage on radiographs did not exhibit a reduction in the amount of buffer-soluble (matrix) protein. Seeds damaged by feeding during early development compensated in part by continuing to synthesize lipid and crystalloid protein. Light or moderate damage to mature Douglas-fir seeds exposed to L. occidentalis in the laboratory reduced seedling emergence by > 80%, but the seedlings that emerged successfully appeared to suffer no adverse effects when grown under standard nursery conditions.     

Influence of Temperament Score and Handling Facility on Stress,Reproductive Hormone Concentrations,and Fixed Time AI Pregnancy Rates in Beef Heifers

The objectives were (i) to evaluate the effect of temperament, determined by modified 2‐point chute exit and gait score, on artificial insemination (AI) pregnancy rates in beef heifers following fixed time AI and (ii) to determine the effect of temperament on cortisol, substance‐P, prolactin and progesterone at initiation of synchronization and at the time of AI. Angus beef heifers (n = 967) at eight locations were included in this study. At the initiation of synchronization (Day 0 = initiation of synchronization), all heifers received a body condition score (BCS), and temperament score (0 = calm; slow exit and walk or 1 = excitable; fast exit or jump or trot or run). Blood samples were collected from a sub‐population of heifers (n = 86) at both synchronization initiation and the time of AI to determine the differences in serum progesterone, cortisol, prolactin and substance‐P concentrations between temperament groups. Heifers were synchronized with 5‐day CO‐Synch+ controlled internal drug release (CIDR) protocol and were inseminated at 56 h after CIDR removal. Heifers were examined for pregnancy by ultrasound 70 days after AI to determine AI pregnancy. Controlling for synchronization treatment (p = 0.03), facility design (p = 0.05), and cattle handling facility design by temperament score interaction (p = 0.02), the AI pregnancy differed between heifers with excitable and calm temperament (51.9% vs 60.3%; p = 0.01). The alley‐way with acute bends and turns, and long straight alley‐way had lower AI pregnancy rate than did the semicircular alley‐way (53.5%, 56.3% and 67.0% respectively; p = 0.05). The serum hormone concentrations differed significantly between different types of cattle handling facility (p < 0.05). The cattle handling facility design by temperament group interactions significantly influenced progesterone (p = 0.01), cortisol (p = 0.01), prolactin (p = 0.02) and substance‐P (p = 0.04) both at the initiation of synchronization and at the time of AI. Inter‐ and intra‐rater agreement for temperament scoring were moderate and good (Kappa = 0.596 ± 0.07 and 0.797 ± 0.11) respectively. The predictive value for calm and pregnant to AI was 0.87, and excited and non‐pregnant to AI was 0.76. In conclusion, the modified 2‐point temperament scoring method can be used to identify heifers with excitable temperament. Heifers with excitable temperament had lower AI pregnancy. Further, cattle handling facility design influenced the temperament and AI pregnancy.     

Determination of Feeder Cell‐Based Cellular Niches Supporting the Colonization and Maintenance of Spermatogonial Stem Cells from Prepubertal Domestic Cat Testes

Recently, isolation and in vitro culture of putative spermatogonial stem cells (SSCs) in the domestic cat have been conducted. However, the cellular niche conditions that facilitate the establishment and long‐term maintenance of feline SSCs (FSSCs) have not been described. Therefore, we investigated the type of feeder cells used to stimulate colony formation and growth of FSSCs among the various factors in the FSSC niche. Spermatogonial stem cells isolated from feline testes were cultured on mitotically inactivated testicular stromal cells (TSCs) derived from cats, dogs and mice, and mouse embryonic fibroblasts (MEFs). The formation and growth of colonies derived from SSCs cultured on each type of feeder cell were identified at passage 0, and the morphology, alkaline phosphatase (AP) activity and expression of SSC‐specific genes in surviving colonies were investigated at passage 4. Among these diverse feeder cells, TSCs from cat showed the greatest colony formation, growth and maintenance of FSSCs, and SSC colonies cultured by passage 4 showed a typical dome‐shaped morphology, AP activity and expression of SSC‐specific genes (NANOG, OCT4, SOX2 and CD9). Accordingly, these results demonstrate that feline TSCs could be used as feeder cells to support the establishment and maintenance of SSCs from domestic cats.     

Monitoring distances travelled by horses using GPS tracking collars

Objective The aims of this work were to (1) develop a low-cost equine movement tracking collar based on readily available components, (2) conduct preliminary studies assessing the effects of both paddock size and internal fence design on the movements of domestic horses, with and without foals at foot, and (3) describe distances moved by mares and their foals. Additional monitoring of free-ranging feral horses was conducted to allow preliminary comparisons with the movement of confined domestic horses. Procedures A lightweight global positioning system (GPS) data logger modified from a personal/vehicle tracker and mounted on a collar was used to monitor the movement of domestic horses in a range of paddock sizes and internal fence designs for 6.5-day periods. Results In the paddocks used (0.8–16 ha), groups of domestic horses exhibited a logarithmic response in mean daily distance travelled as a function of increasing paddock size, tending asymptotically towards approximately 7.5 km/day. The distance moved by newborn foals was similar to their dams, with total distance travelled also dependent on paddock size. Without altering available paddock area, paddock design, with the exception of a spiral design, did not significantly affect mean daily distance travelled. Feral horses (17.9 km/day) travelled substantially greater mean daily distances than domestic horses (7.2 km/day in 16-ha paddock), even when allowing for larger paddock size. Conclusions Horses kept in stables or small yards and paddocks are quite sedentary in comparison with their feral relatives. For a given paddock area, most designs did not significantly affect mean daily distance travelled.     

Preliminary Studies of Artificial Spawning of Channel Catfish as Male-Female Pairs or All-Female Groups in Recirculating Systems

Abstract— Channel catfish Icralurus punctatus are commonly spawned for research purposes by pairing of a hormonally treated female with a male in flow-through aquaria. A technique that allows hormonal induction of ovulation in females without pairing would accelerate genetic improvement and production of hybrid catfish. Over a 3-yr period (1994, 1995, and 1996) we conducted a series of trials to demonstrate the potential for artificial spawning in recirculating systems, and in 1996 we included trials with grouped females in addition to male-female pairs. Females were induced to spawn with injection of synthetic leuteinizing hormone-releasing hormone, and those that ovulated were stripped and the eggs were artificially fertilized. During 1994 and 1995, all fish were spawned by pairing, and in 1996, half of the females were spawned by pairing and half were grouped in tanks without males. Spawning success (percent of females that produced eggs), latency (time between injection and ovulation), and percent fertilization were observed for the paired and grouped trials. Spawning success was 36% in 1994 (N= 36). 22% in 1995 (N= 54). 41% in 1996 (N= 27). and 58% for grouped females (N= 26). The latency period was 113 ± 69 h in 1994, 109 ± 57 h in 1995, 44 ± 8 h in 1996, and 50 ± 9 h for grouped females. Percent fertilization was 16 ± 26% for eggs stripped in 1994, 72 ± 25% in 1995, 43 ± 20% in 1996, and 16 ± 37% for grouped females. In 1995, water quality problems were associated with high mortality of females (24 of 44 females; 4 of 44 males). The metabolic demands of final oocyte maturation in combination with methemoglobinemia caused by high nitrite levels could account for the increased vulnerability of females. These trials indicate that with adequate biofiltration, artificial spawning is possible in recirculating systems and with females grouped rather than paired. Further research on hormone dosage and timing of egg stripping will increase the utility of grouped spawning of channel catfish.     

Genetic correlations among reproductive traits and uterine dimensions in mice

The objective of this experiment was to identify relationships among reproductive and uterine traits in mice having normal or crowded uterine conditions. Littermate females were randomly assigned to be either unilaterally ovariectomized (ULO) or to remain intact (C) and to be killed either 3 d after mating (PM) or 4 d after parturition (PP) in a 2 x 2 factorial design. Measurements taken were ovulation rate (OR) and uterine length (UL), wet weight (UWW), dry weight (UDW) and displacement (UDP) in PM females and number born (NB) and implantation rate (IMP) in PP females. Heritability estimates from full-sib correlations were .18, .01, .33, .04, .14, .47 and .06 for OR, IMP, NB, UL, UWW, UDW and UDP, respectively. Phenotypic correlations among uterine measurements were moderate to high and positive. Genetic correlations for C and ULO females for OR with NB were .62 and .73, respectively. Genetic correlations between C and ULO females were .53 for NB and 1.05 for OR. Genetic correlations of UL and UWW with NB were high for C (.70 and .59, respectively) and moderate for ULO (.47 and .36, respectively). Genetic correlations between NB and other uterine dimensions were lower.     

Unusual osteochondral lesions of the talus in a horse

A 2-year-old Thoroughbred gelding was evaluated for a grade 3 out of 5 unilateral hind limb lameness. Flexion of the right hock and stifle joints (spavin test) exacerbated the lameness. Response to intra-articular and perineural anaesthesia isolated the source of lameness to the tarsocrural area, despite an absence of tarsocrural joint effusion. Routine radiographic examination of the hock did not reveal any significant abnormalities. Skeletal nuclear scintigraphic evaluation revealed a focal region of increased bone activity in the proximal medial trochlear ridge of the talus. Flexed lateromedial radiographic views identified three discrete semicircular lytic lesions at the proximal articular margin of the medial trochlear ridge of the talus. Conservative management of the lesions was associated with a successful return to racing. The location and appearance of the osteochondral lesions of this report have not been previously reported and may be a manifestation of developmental orthopaedic disease and abnormal endochondral ossification. Nuclear scintigraphy and flexed lateromedial radiographic views facilitated identification of the lesions. This radiographic view is recommended when lameness is isolated to the tarsocrural joint and standard radio-graphic projections fail to identify a cause.     

Bulk deposition of metals in Tulsa,Oklahoma

Samples of bulk precipitation were collected at six sites adjacent to the Arkansas River in Tulsa, Oklahoma for a period of 11 mo (June 1980 to April 1981). Collected samples were analyzed by flameless atomic absorbtion spectrophotometry for Cd, Cr, Ni, Pb, and Zn. The data were reported as volume-weighted metal concentrations (μg L¹) and metal deposition (mg m^?2 yr^?1). Metal deposition was fairly constant from site to site and appeared to be proportional to the amount of precipitation collected. Zinc was by far the largest contributing metal, 497 mg m^?2 yr^?1 followed by Pb. Cr, Ni, and Cd with depositions of 25.5, 25.7, 7.02, and 0.95 mg m^?2 yr^?1 respectively. Concentration data varied greatly over the collection period. Compared to data previously reported in the literature, all of the metal concentrations obtained in this study fall within the ranges observed by other investigators with the exception of Zn which was slightly higher. The average volume-weighted concentrations in μg L^?1 were Cd-2.1, Cr-57.0, Ni-15.6, Pb-56.6, and Zn-1100.