Effect of hygiene and medication on preweaning survival and growth of Djallonké sheep in Atacora, Benin

Low sheep productivity in North Benin hampers economic development, and improvement can contribute to reduction of rural poverty and food insecurity. To reduce one of the constraints to the productivity of Djallonké sheep, high mortality during suckling in full rainy and start dry season, we tested hygienic measures and medication in improved housing. The effect of the two treatments and their combination on lamb performance and the internal rate of return (IRR) were compared to a control. For each treatment, survival and growth were observed in 20 lambs, living in 38 herds. Good housing and hygiene (daily cleaning and fortnightly disinfection of stable and water and feed troughs) reduced mortality and increased growth of suckling lambs until 3 months. Good housing plus medication (unique injection of vitamins and amino acids and with ivermectine for deworming, weekly tick treatment by spraying, and in case of diarrhea, antibiotic treatment) reduced mortality, but growth was not higher than the control. Accounting labor opportunity, the IRR was about equal for both, but capital investment was lower for the hygiene treatment which is thus more accessible to poor farmers. The combination of both treatments increased growth and benefits compared with the hygiene treatment, but decreased the IRR.     

Performance of Djallonké Sheep under an Extensive System of Production in Faranah,Guinea

A total of 147 ewes, 4 rams and 188 lambs of their progeny of the Djallonké breed of sheep were used to study the factors affecting reproductive and growth traits and the causes of lamb mortality. Data on ewes were collected during a 12-month period, while those on the lambs born to 123 of the ewes were collected until they were 12 months of age. The average fertility and abortion rates were 0.84 and 0.09. The fertility rate increased and the abortion rate decreased with increasing age of the ewes (p<0.05). The number of lambs born per ewe joined, litter weight at birth per ewe joined and litter weight at weaning per ewe joined were 1.28, 3.5 kg and 17 kg, respectively. The average numbers of lambs born per ewe, lambs born alive per ewe, lambs born dead per ewe and lambs per ewe that died between birth and weaning were 1.53, 1.43, 0.03 and 0.3, respectively. The age of the ewes significantly (p<0.05) affected all these traits except the number of dead lambs and the index of fertility (94%). The age of the ewes significantly (p<0.05) affected the birth weight and the weight at 6 and 12 months of age, whereas the lambing season significantly (p<0.05) affected all the growth traits studied. The type of birth was the most important source of variation in body weights of lambs. Sex had no significant (p>0.05) effect on the growth traits studied. The complex `starvation–bad management–light body weight at birth' caused 48% of the lamb mortality between birth and weaning, while diarrhoea, pneumonia and internal and external parasites caused approximately 52% of the lamb mortality over the same period. The seasonal raw mortality rate of the lambs before weaning was highest in the humid season.     

Investigations into traditionally managed Djallonké-sheep production in the humid and subhumid zones of Asante, Ghana: II. Reproductive events and prolificacy(1)

SUMMARY: Parturitions of 338 among humid-zone ewes and 690 among subhumid-zone ewes gave rise to 361 and 797 live-born lambs, respectively. Mean age and weight at first parity were 431.3 days and 15.6 kg for the humid-zone ewes while those for the subhumid-zone ewes were 429.4 days and 17.0 kg. Early age at first parity is related to physiological age and growth of body weight which is closely related to early sexual maturity. The monthly distribution of parturitions is discussed with considerably higher peaks in October, April and May in the humid zone while in the subhumid zone, high frequencies were recorded in July, August, February and March. Higher parities significantly shortened the successive parturition intervals within and between the climatic zones with general intervals of 234.2 and 208.7 days among the humid- and the subhumid-zone ewes, respectively, at the fifth parity. The shortest parturition intervals (242.6 days) were recorded during the dryspell-minor wet season (August-October) in the humid zone and the major-wet season (May-July; 223.9 days) in the subhumid zone. Higher annual reproduction rates of 1.95 (1st year) and 1.79 (2nd year) lambs among the free-range ewes while subnormal rates of 1.72 (1st year) and 1.68 (2nd year) lambs among the humid-zone ewes were recorded. These differences are related to the natural service, parturition intervals, litter size and the availability of fodder plants as influenced by management (semi-tethering as against free-range). ZUSAMMENFASSUNG: Untersuchungen über traditionelle Schafproduktion in der humiden und sub-humiden Asante Region Ghanas II. Reproduktionsleistungen und Fruchtbarkeitsraten Gegenüber 690 Lebendgeburten bei 338 Mutterschafen in der humiden Zone (H) wurden in der semi-humiden Zone (SH) 797 Geburten bei 361 Mutterschafen erfa?t. Mit einem Erstlammalter zwischen 431,3 (H) und 429,4 (SH) Tagen und K?rpergewichten von 15,6 kg (H) und 17,0 kg (SH) sind Mutterschafe zu diesem Zeitpunkt in der semi- humiden Zone schwerer. Das h?here K?rpergewicht bestimmt weitgehend die sexuelle Frühreife. Die monatliche Verteilung der Ablammungen zeigte deutliche H?ufungen in den Monaten Oktober, April und Mai (H) und Juli, August, Februar und M?rz (SH). Eine h?here Anzahl von Ablammungen führte zu einer signifikanten Verkürzung der aufeinanderfolgenden Ablammungsintervalle innerhalb und zwischen den Klimazonen. Die Zwischenlammzeit zur fünften Ablammung reduzierte sich in der humiden Zone auf 234,2 Tage und in der subhumiden Zone auf 208,7 Tage. Die kürzesten Zwischenlammzeit wurden w?hrend der kleinen 'Dryspell'-Regenzeit (August-Oktober) in der humiden Zone (242,6 Tage) bzw w?hrend der Haupt-regenzeit (Mai-Juli) in der sub-humiden Zone (223,9 Tage) beobachtet. W?hrend h?here Reproduktionsraten von 1,95 L?mmern (1. Jahr) und 1,79 L?mmern (2. Jahr) bei den freilaufenden Mutterschafen in der sub-humiden Zone festgestellt wurden, sind niedrigere Reproduktionsraten von 1,72 L?mmern (1. Jahr) und 1,68 L?mmern (2. Jahr) beim Tüdern in der humiden Zone zu verzeichenen. Als Gründe wurden die Haltungsformen (Tüdern bzw. freie Weidegang), die Wurfgr??e und die verfügbare Futtergrundlage mit ihrem Einflüssen auf die Zwischenlammzeiten analysiert. Insgesamt unterschieden sich hier die Mutterschafe der humiden Zone mit 112,2 % von Mutterschafen der sub-humiden Zone mit 120,4%. RéSUMé: Analyse de la production traditionnelle d'ovins dans les zones humide et sub-humide de la région d'Asante, Ghana II. Rendements de reproduction et taux de fertilité Par rapport aux 690 naissances vives ches 338 brebis dans la zone humide (H), on a enregistré 797 naissances chez 361 brebis dans la zone semi-humide (SH). Avec un age de premier agnelage entre 431,3 (H) et 429,4 (SH) jours et avec un poids vif de 15,6 (H) et 17,0 kg (SH), les brebis, vers ce temps-là, ont plus de poids dans la zone semi-humide. Le poids plus élevé détermine largement la maturité sexuelle précoce. La distribution mensuelle des agnelages montre des fréquences plus élevées aux mois d'octobre, d'avril et de mai (H), et mois de juillet, d'ao?t, de février et de mars (SH). Un nombre plus élevé d'agnelages menait à une diminution significative des intervalles successives d'agnelages non seulement dedans mais aussi entre les zones climatiques. La période entre le quatrième et le cinquième agnelage se réduisait à 234,2 jours dans la zone humide et à 208,7 jours dans la zone sub-humide. La période la plus courte entre deux agnelages qu'on a observée était de 242,6 jours pendant la courte période des pluies, nommée 'dry spelle' (ao?t à octobre) dans la zone humide, et de 223,9 jours pendant la période principale des pluies (mai à juillet) dans la zone sub-humide. On a enregistré des taux plus élevées de reproduction (1,95 agneaux pendant la première année, et 1,79 agneaux pendant la deuxième) chez les brebis paturant librement, dans la zone sub-humide, et des taux plus bas de reproduction (1,72 agneaux/la première année et 1,68/la deuxième) chez les brebis paturant au piquet, dans la zone humide. Les formes d'entretien (paturage au piquet ou paturage libre), la taille de la portée et la disponibilité de fourrage ont été analysés comme des facteurs importants sur les périodes entre les agnelages.     

Pharmacokinetics and renal clearance of sulphadimidine,sulphamerazine and sulphadiazine and their N4‐acetyl and hydroxy metabolites in pigs

Summary

The effect of molecular structure on the drug disposition and protein binding in plasma, the urinary recovery, and the renal clearance of sulphamerazine (SMR), sulphadiazine (SDZ), and sulphadimidine (SDM) and their N₄‐acetyl and hydroxy derivatives were studied in pigs. Following IV administration of SDM, SMR and SDZ, their mean elimination half‐lives were 12.4 h, 4.3 h and 4.9 h respectively. The plasma concentrations of parent sulphonamide were higher than those of the metabolites, and ran parallel. The acetylated derivatives were the main metabolites; traces of 6‐hydroxymethylsulphamerazine and 4‐hydroxysulphadiazine were detected in plasma.

The urine recovery data showed that in pigs acetylation is the major elimination pathway of SDM, SMR and SDZ; hydroxylation became more important in case of SMR (6‐hydroxymethyl and 4‐hydroxy derivatives) and SDZ (4‐hydroxy derivatives) than in SDM. In pigs methyl substitution of the pyrimidine side chain decreased the renal clearance of the parent drug and made the parent compound less accessible for hydroxylation. Acetylation and hydroxylation speeded up drug elimentation, because their renal clearance values were higher than those of the parent drug.     

Essential oil of Aloysia citriodora Paláu and citral: sedative and anesthetic efficacy and safety in Rhamdia quelen and Ctenopharyngodon idella

ObjectiveTo verify the efficacy of citral in inducing sedation and anesthesia in silver catfish (Rhamdia quelen) and grass carp (Ctenopharyngodon idella) and to assess the safety of essential oil (EO) of Aloysia citriodora and citral in inducing and maintaining anesthesia in silver catfish.Study designClinical study, randomized, parallel, multi-arm with control group in target species.AnimalsA total of 96 juvenile and 72 adult silver catfish and 80 juvenile grass carp were used.MethodsSilver catfish and grass carp were exposed to different concentrations of citral, 15–675 and 15–600 μL L^–1, respectively, during the maximum period of 30 minutes to verify sedation and anesthesia induction and recovery times. In addition, for anesthetic induction, silver catfish were exposed to the EO of A. citriodora and citral at 225 μL L^–1 for 3.5 minutes. Then, fish were transferred to an anesthesia maintenance solution at 50 μL L^–1 for 10 minutes to assess hematologic and biochemical variables at 60 minutes, 2 and 6 days after treatment.ResultsCitral only induced sedation from 15, 25 and 40 μLL^–1 in both species. Anesthesia without mortality was induced in silver catfish at 50–600 μL L^–1 and grass carp at 75–450 μL L^–1. At 675 and 600 μL L^–1, mortality was recorded in silver catfish and grass carp, respectively. The EO of A. citriodora and citral were safe in inducing and maintaining anesthesia in silver catfish, with mean corpuscular hemoglobin concentration being the only variable that varied in relation to time and treatments.Conclusions and clinical relevanceCitral was effective in inducing sedation and anesthesia in both species. In addition, A. citriodora EO and citral were safe in inducing and maintaining anesthesia in silver catfish. Both agents are promising substances for the development of new drugs for fish.     

Informal value chain actors’ knowledge and perceptions about zoonotic diseases and biosecurity in Kenya and the importance for food safety and public health

Zoonotic diseases, transmitted from animals to humans, are a public health challenge in developing countries. Livestock value chain actors have an important role to play as the first line of defence in safeguarding public health. However, although the livelihood and economic impacts of zoonoses are widely known, adoption of biosecurity measures aimed at preventing zoonoses is low, particularly among actors in informal livestock value chains in low and middle-income countries. The main objective of this study was to investigate knowledge of zoonoses and adoption of biosecurity measures by livestock and milk value chain actors in Bura, Tana River County, in Kenya, where cattle, camels, sheep and goats are the main livestock kept. The study utilised a mixed methods approach, with a questionnaire survey administered to 154 value chain actors. Additional information was elicited through key informant interviews and participatory methods with relevant stakeholders outside the value chain. Our results found low levels of knowledge of zoonoses and low levels of adherence to food safety standards, with only 37% of milk traders knowing about brucellosis, in spite of a sero-prevalence of 9% in the small ruminants tested in this study, and no slaughterhouse worker knew about Q fever. Actors had little formal education (between 0 and 10%) and lacked training in food safety and biosecurity measures. Adoption of biosecurity measures by value chain actors was very low or non-existent, with only 11% of butchers wearing gloves. There was a gendered dimension, evidenced by markedly different participation in value chains and lower adoption rates and knowledge levels among female actors. Finally, cultural and religious practices were shown to play an important role in exposure and transmission of diseases, influencing perceptions and attitudes to risks and adoption of biosecurity measures.     

Nesting and dust bathing by hens in cages: Matching and mis‐matching between behaviour and environment

1. Medium hybrid hens were housed as groups of 4 at 18 weeks of age in cages of 4 different types: control battery cages allowing 675 cm2/bird; similar cages with a rear‐mounted dust bath, 290×345×240 mm, containing sand (D); cages with a rear‐mounted nest box of the same size, containing wood shavings (N); cages with both (DN). In half the experimental cages access to nests was restricted to the morning and access to baths was restricted to the afternoon, by automatic sliding doors.

2. During the first 24 weeks of lay about 95% of eggs were laid in nest boxes in treatments N and DN. Slightly fewer were laid in boxes where doors were present. Over 90% were laid in dust baths in D cages without doors and 67% with doors, which birds learned to open. Prelaying behaviour was least disturbed in nest boxes, most disturbed on the floor and intermediate in dust baths.

3. Fully developed dust bathing occurred in D and DN as bouts lasting 5 to 10 minutes; its incidence, surprisingly, was greater when doors were present and greater still when nest boxes were present, even though it was not performed in them. It was also performed by some hens in nest boxes in N (without doors). In N with doors and in control cages, dust bathing occurred on the bare floor in truncated form, as serial bouts each lasting only about 10 s. This truncated dust bathing was also occasionally observed in D and DN.

4. Plumage, foot and claw damage were less in hens from modified cages than from controls. Egg production was very good in all treatments but more eggs from control cages were downgraded because they were dirty or cracked.

5. When a choice was available birds generally partitioned their behaviour appropriately between nest box and dust bath. In N and DN virtually all prelaying and nesting behaviour took place in the nest boxes. Matching between dust bathing and the environment was less close; the reasons for its relatively low incidence and occurrence in truncated form outside dust baths remain to be established.     

Abnormal platelet activity in dogs and cats – impact and measurement

Abnormal platelet activity can either lead to bleeding tendencies or inappropriate thrombus formation and can occur secondarily to a wide variety of disease processes, with a range of clinical consequences and severity. This article will discuss the pathophysiology of platelet function abnormalities and consider a logical diagnostic approach applicable to veterinary practice. Recent advances in platelet function testing will then be discussed, with regards to detection of platelet dysfunction and tailoring of pharmacological manipulation. Although many of these tests are still confined to research or academic institutions, techniques for indirectly assessing platelet function are starting to become more widely available. Although we still require further research to develop guidelines for the use of these tests in clinical decision-making, the recent advances in this field are an exciting step forward in being able to detect and manage platelet dysfunction in both primary care and referral practice.     

Experimental determination and allometric prediction of vitreous volume, and retina and lens weights in Göttingen minipigs

Objectives To determine the vitreous volume, and retinal and lens wet weights in male and female Göttingen minipigs of different age groups. Procedures Vitreous, lens and retina were isolated from fresh minipig eyes. Vitreous volume, lens and retina weight were measured and allometric scaling was utilized to predict these parameters. Results There were no gender differences in body weights or retina and lens weights in the three age groups examined in this study. For vitreous volumes, females had a significantly larger volume (approximately 10%–12%) than males in the 4–6 and 6–8 month, but not in the 8–11‐month group. The mean body weight increased from 12.2 ± 2.6 kg (4–6 months) to 19.4 ± 4.0 kg (8–11 months). In the same period, the mean vitreous volume increased from 2.00 ± 0.28 to 2.67 ± 0.31 mL, while the mean retinal and lens weights increased from 114 ± 22 to 126 ± 17 mg, and from 298 ± 26 to 392 ± 15 mg, respectively. Allometric analysis between six species for vitreous volume and four species for lens weight covering a weight range of 260‐fold was not able to estimate the vitreous volume, but it did predict the lens weight in 8–11 months minipigs. Conclusions Overall these measurements add important context to intraocular pharmacology studies, and will help in the improved design and interpretation of such experiments.     

Production benefits of the crossbreeding of indigenous and non-indigenous ducks—growing and laying period body weight and production performance

To evaluate different crosses and purebreds ducks in respect to various economic traits and to estimate different crossbreeding genetic parameters, a 3?×?3 complete diallel cross involving indigenous duck (DD), Khaki Campbell (KK) and White Pekin (WW) were used to produce three purebreds (DD, KK, WW) three crossbreds (DK, DW, KW) and three reciprocals (KD, WD, WK). A total of 609 ducklings produced were reared on deep litter and the females (316 in number) were evaluated for growing and laying period body weight along with the production performance traits. Different crossbreeding genetic parameters were estimated for different traits. All the traits in respect to body weight gain during growing and laying period and different production traits including laying house mortality rate showed significant (p?≤?0.05) difference between different genetic groups. In general, crossbreds perform better than the purebreds for most of the traits studied. General combining ability (GCA), specific combining ability (SCA) and reciprocal effect (RE) were significant (p?≤?0.01) for body weight and production traits. Egg weight showed significant (p?≤?0.01) difference in respect to GCA, SCA and RE for all the ages of measurement except RE for 30th week egg weight. Laying period mortality rate was only significant (p?≤?0.05) for SCA. Most of the crossbreds recorded heterosis rate in desirable direction for majority of the traits. Overall results revealed that the crossbreds perform well in respect to different traits than the purebreds and may be used to take advantage of heterosis. DW performs well in respect to majority of the traits measured and is of importance for commercial exploitation. Further, pure line selection with development of specialised sire and dam line followed by crossing may be of importance to enhance the performances in the crosses.     

Functional genomics and evolution of tick–Anaplasma interactions and vaccine development

The genus Anaplasma (Rickettsiales: Anaplasmataceae) includes several tick-transmitted pathogens that impact veterinary and human health. Tick-borne pathogens cycle between tick vectors and vertebrate hosts and their interaction is mediated by molecular mechanisms at the tick–pathogen interface. These mechanisms have evolved characteristics that involve traits from both the tick vector and the pathogen to insure their mutual survival. Herein, we review the information obtained from functional genomics and genetic studies to characterize the tick–Anaplasma interface and evolution of A. marginale and A. phagocytophilum. Anaplasma and tick genes and proteins involved in tick–pathogen interactions were characterized. The results of these studies demonstrated that common and Anaplasma species-specific molecular mechanism occur by which pathogen and tick cell gene expression mediates or limits Anaplasma developmental cycle and trafficking through ticks. These results have advanced our understanding of the biology of tick–Anaplasma interactions and have opened new avenues for the development of improved methods for the control of tick infestations and the transmission of tick-borne pathogens.     

Development and use of real-time PCR to detect and quantify Mycoplasma haemocanis and “Candidatus Mycoplasma haematoparvum” in dogs

Two canine haemoplasma species have been recognised to date; Mycoplasma haemocanis (Mhc), which has been associated with anaemia in splenectomised or immunocompromised dogs, and “Candidatus Mycoplasma haematoparvum” (CMhp), recently described in an anaemic splenectomised dog undergoing chemotherapy. The study aim was to develop quantitative real-time PCR assays (qPCRs) incorporating an endogenous internal control to detect Mhc and CMhp and to apply these assays to DNA samples extracted from canine blood collected in Northern Tanzania (n = 100) and from dogs presented to a Trinidadian veterinary hospital (n = 185).QPCRs specific for Mhc and CMhp were designed using 16S rRNA gene sequence data, and each was duplexed with an assay specific for canine glyceraldehyde-3-phosphate dehydrogenase (GAPDH). The assays detected ≤10 copies of a sequence-specific haemoplasma plasmid per reaction and neither assay showed cross-reactivity with 10⁶ copies of the sequence-specific plasmid from the non-target canine haemoplasma species.Nineteen of the 100 Tanzanian samples (19%) were positive for Mhc alone and one (1%) was dually infected. One Trinidadian sample was negative for canine GAPDH DNA and was excluded from the study. Of the 184 remaining Trinidadian samples, nine (4.9%) were positive for Mhc alone, five (2.7%) for CMhp alone, and two (1.1%) dually infected.This is the first report of canine haemoplasma qPCR assays that use an internal control to confirm the presence of amplifiable sample DNA, and their application to prevalence studies. Mhc was the most commonly detected canine haemoplasma species.     

Kinetics and role of antibodies against intimin β in colostrum and in serum from goat kids and longitudinal study of attaching and effacing Escherichia coli in goat kids

The presence of antibodies to the intimin β-binding region (Int280-β) of attaching and effacing Escherichia coli (AEEC) in serum from 20 goat kids from 2 herds, as well as in goat colostrum, was investigated by enzyme-linked immunosorbent assay. In addition, the onset and subsequent pattern of shedding of AEEC from the same goat kids over a 6-mo period was investigated. All the colostrum and serum samples tested contained antibodies against Int280-β. The association between the antibody titer and the isolation of AEEC suggests that antibodies to intimin β do not prevent colonization of the intestine by AEEC in goat kids. The AEEC were generally shed only transiently. Most AEEC isolated from the kids belonged to serogroup O26. Three isolates belonged to serogroup O157. These data show that goat kids may be a reservoir of AEEC that are potentially pathogenic for humans.