Assessing carcass and meat characteristics of Damara, Dorper and Australian Merino lambs under restricted feeding

Seasonal weight loss (SWL) is the most pressing constraint in ruminant production systems in tropical climates. SWL is controlled using supplementation, which is costly and difficult to implement in extensive systems, or using breeds adapted to tropical hot dry climates, like the Damara and Dorper. Albeit 15 years in Australia, little is known on how these sheep compare to Australian Merino. Here, the responses of the Damara, Dorper and Merino breeds to nutritional stress were compared. Seventy-two 6-month-old ram lambs, 24 from each breed, were allocated to growth (gaining 100 g/day) or restricted diets (losing 100 g/day, 85 % of maintenance needs). Animals were weighed and carcass and meat characteristics determined. Results point out to the existence of important differences between the three genotypes, in particular between the Merino and the Southern African breeds. Additionally, Merino ram lambs seem to have been more influenced by SWL than the other two, with consequences on meat characteristics.     

Susceptibility of the namchi and kapsiki cattle of cameroon to trypanosome infection

Summary Two indigenous Cameroonian taurine cattle breeds (Namchi and Kapsiki) were evaluated for trypanosusceptibility following inoculation withTrypanosoma congolense. The degree of zebu ancestry in the experimental animals was assessed using 6 microsatellite markers which are known to have certain unique alleles which are diagnostic ofBos indicus genetic input. Their response to the infection was compared to that of known trypanotolerant (N’Dama) and trypanosusceptible (Ngaoundere Gudali) cattle. The Namchi and the N’Dama controlled the development and severity of anaemia and parasitaemia better than the Kapsiki and the Gudali. For these parameters, there was no significant difference between the N’Dama and Namchi nor between the Kapsiki and Gudali. Similarly, weight loss showed significant breed variation. The N’Dama lost the least weight and the Kapsiki the most. Zebu introgression in the Namchi was comparable to that in the N’Dama while that of the Kapsiki breed was higher, indicating a high level of cross breeding. From the results, the Namchi are considered trypanotolerant while the Kapsiki are trypanosusceptible. The potential exploitation of the indigenous Namchi cattle is discussed.

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Susceptibilidad Del Ganado Vacuno De Raza Namchi Y Kapsiki De Camerun A La Tripanosomiasis

Resumen Dos razas de ganado vacuno de Camerún pertenecientes al tronco europeo (Namchi y Kapsiki) fueron evaluadas para determinar su tripanosusceptibilidad tras ser inoculadas conTrypanosoma congolense. El porcentaje de sangre cebú en los animales experimentales se evaluó mediante microsatélites que contienen alelos específicos deBos indicus. La respuesta de los animales a la infestación se comparó con la de animales tripanotolerantes (N’Dama) y tripanosusceptibles (Ngaoundere Gudali). Los animales de raza Namchi y N’Dama controlaron el desarrollo y severidad de la anemia y de la parasitemia mejor que los animales de raza Kapsiki y Gudali. En relación a estos parámetros no hubo diferencias significativas entre las razas N’Dama y Namchi por una parte ni tampoco entre las razas Kapsiki y Gudali por otra. Igualmente, la pérdida de peso mostró un efecto significativo de la raza. Los animales de raza N’Dama fueron los que perdieron menos peso, mientras que los animales de raza Kapsiki fueron los que perdieron más peso. El porcentaje de sangre cebú en las razas Namchi y N’Dama fue similar, mientras que el de la raza Kapsiki fue superior, indicando un alto nivel de cruzamiento. A partir de los resultados obtenidos, puede concluirse que la raza Namchi es tripantotolerante y la raza Kapsiki es tripanosusceptible.

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Susceptibilite Des Races Bovines Namchi Et Kasiki Aux Infections Par Les Tryanosomes Au Cameroun

Résumé La suceptibilité aux trypanosomes fut évaluée chez 2 races indigènes de bétail camerounais (Namchi et Kapsiki) après infection avecTrypanosoma congolense. Six microsondes furent utilisées chez les animaux pour conna?tre leur filiation avec la race zebu, ces sondes étant connues comme présentant des allèles particuliers permettant de suivre l’apport genétique d? àBos indicus. Leur réaction à l’infection fut comparée à celle observée chez une race resistante (N’Dama) et une race susceptible (Ngaoundéré Gudali). Le développement et la sévérité des anèmies et des parasites furent mieux controlés chez les races Namchi et N’Dama que chez les races Kapsiki et Gudali. Pour ces paramètres il ne fut pas observé de différence significative entre les races appartenant au même groupe. De même, la perte en poids fut liée à la race étudiée. La race N’Dama montra la plus faible perte de poids et la race Kapsiki, la plus importante. Les races Namchi et N’Dama montrèrent des niveaux de croisement identique, la race Kapsiki étant la plus génétiquement modifiée. D’après ces résultats la race Namchi est considérée comme résistante aux trypanosomes alors que la race Kapsiki est susceptible aux infections par trypanosomes. Les utilisations potentielles de la race indigène sont discutées.

     

Plasma concentrations of buprenorphine after epidural administration in conscious cats

Buprenorphine plasma concentrations were measured after administering buprenorphine (20 μg/kg) into the lumbosacral epidural space of conscious cats chronically instrumented with an epidural catheter. Blood was collected from a jugular vein before injection and 15, 30, 45 and 60 min and 2, 3, 4, 5, 6, 8, 12 and 24 h after administration. Plasma buprenorphine concentrations were measured using ELISA. Background concentration (before injection) was 1.27 ± 0.27 ng/mL (mean ± SD). Including background concentration, the mean peak plasma concentration was obtained 15 min after injection (5.82 ± 3.75 ng/mL), and ranged from 3.79 to 2.20 ng/mL (30 min–3 h), remaining between 1.93 and 1.77 ng/mL (4–12 h), and declined to 1.40 ± 0.62 ng/mL at 24 h. Elimination half-life was 58.8 ± 40.2 min and clearance 56.7 ± 21.5 mL/min. Results indicate early rapid systemic uptake of buprenorphine from epidural administration with plasma concentrations similar to using buccal or IM routes by 15 min postinjection.     

Irrigation water quality and ion balance in leaves of deciduous ornamental trees

In arid and semi‐arid regions, evaporation losses exceed replenishment from fresh water tributaries reducing water quality due to accumulation of salts. Increasing human demand for high‐quality waters has encouraged use of low‐quality, nonpotable water for landscape and agricultural irrigation. However, when used alone for irrigation, growth and appearance of some woody ornamentals are negatively impacted. To date, little is known of the impacts of low‐quality water on ion uptake and salt tolerance of most ornamental plants. Three replications of five deciduous ornamental trees were randomly planted and treated with three blended irrigation waters of high‐, medium‐, and low‐quality water [15, 80, and 120 mg sodium (Na) L¹, respectively] in a split‐plot design. Leaf tissues were sampled on October 1996 and September 1997 and analyzed for nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), Na, zinc (Zn), iron (Fe), manganese (Mn), and copper (Cu). The five tree species varied in their responses to irrigation treatment with water of decreasing quality with some having increasing and others decreasing contents of a specific nutrient element. Further, although impact of low‐quality water was evident, none of the minerals tested were in the deficient or toxic range.     

Application of marker‐assisted selection and genome‐wide association scanning to the development of winter food barley germplasm resources

Barley (Hordeum vulgare) is an important component of heart‐healthy whole grain diets because it contains β‐glucan. All current US barley varieties with high β‐glucan are spring habit and have waxy starch. Winter varieties have agronomic advantages but require low‐temperature tolerance (LTT). Vernalization sensitivity (VS) is associated with higher levels of LTT. To rapidly develop fall‐sown varieties with LTT and higher grain β‐glucan, we therefore used marker‐assisted selection (MAS) at the WX and VRN‐H2 loci. The MAS‐derived lines, together with unrelated non‐waxy germplasm developed via phenotypic selection (PS), were used for a genome‐wide association scan (GWAS). The panel was phenotyped for grain β‐glucan, LTT and VS. It was genotyped with 3072 single‐nucleotide polymorphisms (SNPs) and allele‐specific primers. Marker‐assisted selection fixed target alleles at both loci but only one of the target phenotypes (higher β‐glucan percentage) was achieved. Variation for VS and LTT is attributable to (i) incomplete information about VRN‐H1 at the outset of the project and (ii) unexpected allelic variation at VRN‐H3 with a large effect on VS and LTT.     

Effect of low dose rate ketamine infusions on thermal and mechanical thresholds in conscious cats

ObjectiveTo determine the thermal and mechanical antinociceptive effects of two different subanesthetic constant rate infusions of racemic ketamine in cats.Study designProspective, randomized, blinded, experimental study.AnimalsEight healthy adult domestic shorthair cats (two intact females and six neutered males).MethodsThe thorax and the lower thoracic limbs of each cat were shaved for thermal (TT) and mechanical threshold (MT) testing and a cephalic catheter was placed. Three intravenous treatments of equivalent volume were given as loading dose (LD) followed by an infusion for 2 hours: (K5) 0.5 mg kg^?1 ketamine followed by 5 μg kg^?1 minute^?1 ketamine infusion, (K23) 0.5 mg kg^?1 ketamine followed by 23 μg kg^?1 minute^?1 ketamine infusion or (S) 0.9% saline solution. Effects on behavior, sedation scores, MT and TT were obtained prior to drug treatment and 0.25, 0.5, 0.75, 1, 1.5, 2, 2.25, 2.5 2.75, 3 hours then every 0.5 hours for 7 hours and 10, 12, 14 and 26 hours after loading dose administration.ResultsKetamine induced mild sedation for the period of the infusion, no adverse behavioral effects were observed. Thermal threshold was significantly higher than baseline (K5: 44.5 ± 0.7 °C; K23: 44.5 ± 0.5 °C) at 15 minutes in the K5 group (46.8 ± 3.5 °C) and at 45 minutes in the K23 group (47.1 ± 4.1 °C). In the K23 group TT was significantly increased compared to S and K5 at 45 minutes. In K5 at 15 minutes MT (9.6 ± 4.0 N) was different to baseline (6.1 ± 0.8 N) and to the S group (5.9 ± 2.3 N).Conclusion and clinical relevanceLow dose rate ketamine infusions minimally affect thermal and mechanical antinociception in cats. Further studies with different nociceptive testing methods are necessary to assess whether ketamine could be a useful analgesic in cats.     

Foot and Mouth Disease and Livestock Husbandry Practices in the Adamawa Province of Cameroon

Foot and mouth disease (FMD) is a highly contagious viral disease of even-toed ungulates and is endemic in most of the tropics. A cross-sectional study using a stratified, two-stage random sample design was undertaken in the Adamawa Province of Cameroon. The objectives were to measure the reported herd-level prevalence of FMD and a range of husbandry practices important for its transmission. The owner-reported prevalence for the previous 12 months was 57.9% (50.4–65.4%), although there was a significant variation across the Province. During the previous dry season, 46.5% (38.6–54.4%) of herds had gone on transhumance. Herds had high numbers of contacts with other herds while on transhumance (98.6%), at pasture (95.8%) and at night (74.4%), with medians of 7–10, 4–6 and 1–3 daily contacts, respectively. The high level of endemic FMD and potential for disease spread presents a significant challenge for control and eradication. Locally sustainable methods need to be developed upon which larger regional control programmes could be built in the future.