Genetic survey in smallholder dairy production system of Southern province of Zambia.

Milk production among the smallholder dairy farmers in Zambia is reported to be low despite improvements in milk collection infrastructure and unmet demand by the populace. This study was conducted to characterize cattle breeds and the breeding strategies of the smallholder dairy production system in the Southern province of Zambia. The study was conducted using questionnaires to obtain responses from identified respondents in six districts considered the main dairy cattle producing areas. One hundred and twenty questionnaires were administered and available for descriptive statistical analysis. The cattle genetic groups included local (Tonga and Angoni) breeds and their crosses (40.0%); beef (Boran and Brahman) breeds and their crosses (23.3%); Friesian breed and its crosses (28.8%); Jersey breed and its crosses (4.9%); and Fleckvieh breed (3.0%). Calving rate was found to be to be between 36% and 50% for the dairy herds. Compared to the other genetic groups, it was noted that Friesian and its crosses had higher milk production (3.55 L vs. 1.4 L). The low milk yield reported could be attributed to the period of study, which coincided with the long dry season between April and October. The Friesian and its crosses recorded earlier age at first calving (2.65 vs. 2.8 years), shorter longevity (10.5 vs. 12.25 years), and shorter lactation length (7.5 vs. 9.25 months). Jersey and its crosses, on the other hand, had an above average performance for all indices of economic importance such as milk production, lactation length, age at first calving, longevity, and number of calves produced. The results indicated natural mating was practised by 85% of the farmers. Farmer-preferred traits include size and conformation (23%); performance and colour (16% and 15%, respectively) in the choice of a bull. Selection by farmers were thus based on simple observation without pedigree or performance-based genetic evaluation. It was apparent that the smallholder dairy production system is in a shifting trend to transform the mainly local and beef breed animals into dairy herds through crossing with exotic dairy breeds. The production system is, however, faced with the challenges of water and feed supply to meet nutritional requirements, and high disease burden. Jersey breed was found to be a logical choice for the resource poor smallholder dairy farmers. The development and management of the smallholder dairy breeding schemes should be all-inclusive and directed at the prevalent production systems with the aim of also improving the feeding and management practices.

Pseudomonas aeruginosa Infection in a Group of Captive Humboldt Penguins ( Spheniscus humboldti ).

Nine Humboldt penguins ( Spheniscus humboldti ), between 1 and 1.5 years old and kept at Zoo Dresden, developed local and systemic infections with various opportunistic pathogens within a period of 4 months. Affected birds died peracutely without preceding symptoms or showed various clinical signs, including separation from conspecifics, reduced food intake, lethargy, dyspnea, swelling of the salt glands, and ocular discharge. One bird showed central nervous signs, including seizures. Pathologic examination of deceased birds revealed severe necrotizing inflammation of the mucous membranes and deep structures of the glottis, trachea, nasal sinus, and conchae and granulomatous inflammation of the salt glands. Further findings were airsacculitis, pneumonia, hepatitis, conjunctivitis, and myositis. Pseudomonas aeruginosa was the predominant pathogen in 7 cases. Six penguins died or were euthanatized, whereas 3 penguins that received systemic antibiotic treatment with tobramycin (10 mg/kg IM q24h for 10 days) showed rapid clinical improvement. Insufficient turnover rate of the filtration system, biofilm formation on pipe surfaces, and other factors are assumed to have promoted pathogen buildup in the pool water and subsequent infection.

Erysipelas in a free-range layer flock with conjunctival oedema as an unusual clinical sign.

Erysipelas was diagnosed in a free-range laying flock with a high mortality of up to 7% per day and a severe decrease in egg production to 45%. The disease had a short course and unusual clinical features for erysipelas, including swollen, lacrimating and encrusted eyes. Bacteriologically, trapped poultry red mites and affected animals were culture-positive for Erysipelothrix rhusiopathiae. Isolates from layers and mites were both serotype 1b. Histopathology revealed disseminated intravasal coagulopathy in conjunctival small vessels as the cause of the oedema of the eye adnexes. After treatment with penicillin, mortality and egg production returned to normal levels. Although erysipelas in laying hens is rarely reported, it can develop as an emerging disease in alternative rearing systems and should always be considered if mortality increases in an older flock, especially with a high infestation of poultry red mites.

Adenoviral gizzard erosion in broiler chickens in Germany.

Avian adenovirus infections cause important disease complexes in chickens, but many of the viruses also infect chickens without resulting in overt disease. Previously several outbreaks of gizzard erosions caused by a fowl adenovirus A serotype-1 (FAdV-1) were reported from Japan. Here we report an outbreak of gizzard erosions in 12 broiler flocks in Germany in 2011. Chickens had a reduced daily weight gain and a higher total mortality rate of up to 8%. The birds showed a severe detachment of the koilin layer and ulcerative to necrotizing lesions of the underlying mucosa. Histopathologically, necrotizing ventriculitis with basophilic, intranuclear inclusion bodies in epithelial cells was diagnosed. Immunohistochemistry, egg culture, and electron microscopic examination revealed adenovirus-like particles in the samples. No concurrent infectious agent could be identified. The virus was genotyped as FAdV-1 by PCR and subsequent sequencing. Phylogenetic analysis of the hexon loop L1 gene yielded 100% sequence identity to the chicken embryo lethal orphan strain. These findings suggest that outbreaks of adenoviral gizzard erosion can lead to significant economic losses in Germany and may be caused by an unusual virulent FAdV-1 strain.

Characterization of the chicken CD200 receptor family.

The modulation of myeloid cells via inhibitory and activating immunoglobulin superfamily members has been a subject of intense study in mammals. One such example is the inhibitory receptor for CD200, which is shown to regulate the activation threshold of myeloid cells by interaction with the broadly distributed CD200 molecule. By looking at sequence homology and synteny conservation in the chicken genome, we identified two members of the CD200 receptor family in chicken on chromosome one. Cloning and further characterization of the protein sequence yielded a potentially inhibitory ggCD200R-B1 with a splice variant lacking a transmembrane region and a potentially soluble ggCD200R-S1. Both showed a typical V/C2-set Ig domain arrangement and we present evidence that these two genes have evolved by gene duplication. The inhibitory receptor displayed an uncharged transmembrane region and a long cytoplasmic tail encoding four tyrosine residues, one of them embedded in a motif similar to the mammalian NPxY motif. Further characterization of ggCD200R-B1 showed that it is expressed as a highly glycosylated protein and that its cytoplasmic tyrosine residues can be phosphorylated. Real-time RT-PCR analysis of various tissues and primary cells showed that ggCD200R-B1 is predominantly expressed in macrophages, whereas ggCD200R-S1 is highly expressed in peripheral blood mononuclear cells, but not macrophages. In summary, we showed that there is a homologue of mammalian CD200R conserved in chicken suggesting a similar function in avian species. Furthermore, the presence of potentially soluble CD200R molecules implies an important role for these in the regulation of myeloid cells in chicken.