Associations between lamb growth to weaning and dam udder and teat scores

ABSTRACT

Aims: To investigate associations between lamb growth to weaning and dam udder and teat scores measured at pre-mating, pre-lambing, docking and weaning.

Methods: Mature Romney ewes (n?=?1,009) were enrolled from a commercial sheep flock located near Masterton, in the Wellington region of New Zealand in 2017. A range of udder and teat traits were scored in all ewes, using visual assessment and palpation, at pre-mating, pre-lambing, docking and weaning. During the lambing period, each newborn lamb was matched to its dam and lamb sex, birthweight and birth-rank were recorded. A rearing rank was allocated to each live-lamb at weaning, when all lambs were weighed (n?=?1,570), allowing calculation of daily growth rates (g/day). Associations between udder and teat scores and lamb growth rates to weaning were examined using multivariable models for each udder-scoring time.

Results: Growth rates of lambs whose dams had udder palpation scores of hard, or both teats recorded as abnormal, pre-mating were lower than lambs whose dams had normal scores (229.9 (95% CI?=?213.2–246.6) vs. 254.5 (95% CI?=?245.6–263.5) g/day; p?=?0.011) and (227.4 (95% CI?=?208.3–246.6) vs. 247.9 (95% CI?=?235.7–260.2) g/day; p?=?0.024), respectively. Growth rates of lambs whose dams had clinical mastitis at docking or weaning were lower than those without mastitis (215.8 (95% CI?=?199.9–231.7) vs. 235.4 (95% CI?=?225.4–255.0) g/day; p?=?0.007) and (220.0 (95% CI?=?205.2–234.8) vs. 254.7 (95% CI?=?248.9–260.5) g/day; p?<?0.001), respectively. Growth rates of lambs whose dams had asymmetrical udders at docking or weaning were lower than lambs whose dams had symmetrical udders (204.6 (95% CI?=?189.7–219.5) vs. 240.2 (95% CI?=?225.4–255.0) g/day; p?<?0.001) and (223.3 (95% CI?=?213.9–232.7) vs. 242.2 (95% CI?=?229.4–255.0) g/day; p?=?0.014), respectively.

Conclusions and Clinical Relevance: Pre-mating udder palpation and teat palpation scores can be used to identify ewes whose lambs are predicted to have lower growth to weaning. Assuming a mean lamb age at weaning of 84.4 days, lambs born to ewes with a pre-mating score of hard would be expected to have a mean weaning weight that was 2.1?kg less than those whose dams had normal scores. Udder palpation, udder symmetry and clinical mastitis scores during lactation were also associated with lamb growth rates.

Abbreviation: CALW: Conceptus-adjusted liveweight     

Relationship between California Mastitis Test score and ultrasonographic teat measurements in dairy cows

Objective The majority of published studies about mastitis are related to the control and prevention of mastitis, with particular emphasis on eliminating predisposition factors. The objective of the current study was to determine the role of teat morphology as an important factor in the aetiology of mastitis. Design Ultrasonographic measurements were taken from 190 teats from 100 dairy cows of different breeds. Procedure Mastitis in cows was diagnosed by the California Mastitis Test (CMT) and microbiological tests. The data were evaluated in the light of the clinical history of the animals. Results Main effects of breed on teat diameter at the position of the Furstenberg rosette (FTD) and teat cistern diameter (CD), that of age on FTD and overall teat diameter (OTD), and that of CMT score on CD and OTD were significant (P < 0.05, P < 0.01). Number of lactations, pregnancy, the lactation period and the udder lobe (rear, front) were not found to have a significant effect on any of the measurements. Results showed that CD was significantly smaller (1.44 ± 0.04 cm) (P < 0.01) in CMT‐positive udder lobes than that in CMT‐negative lobes. No difference was detected in canal length, CD, teat wall thickness, OTD or FTD between the CMT‐positive and ‐negative lobes. Conclusion The occurrence of mastitis could be related to specific ultrasonographic teat measurements (e.g. CD, OTD and FTD) and these may be important in the breeding of cows with a predisposition to mastitis, as well in the evaluation of in‐herd cows in terms of udder/teat deformities.     

B-mode ultrasonography of the bovine udder and teat

The udders and teats of cows were examined by brightness mode (B-mode) ultrasonography. A 5-MHz linear array transducer and a 5-MHz or 10-MHz mechanical sector transducer were used in the examinations. In lactating animals, the teat sinus, gland sinus, and lactiferous ducts were imaged easily. The scans also allowed visualization of the layers of the teat wall. The annular fold and the folding of the mucosa at the junction of the teat sinus and the papillary duct were seen best with the 5-MHz and 10-MHz mechanical sector transducers. In one cow lacking milk flow from one quarter, a mass at the junction of the papillary duct and the teat sinus was observed ultrasonographically. Surgical removal of the mass resulted in a return of milk flow from that quarter.     

Efficacy of ivermectin against gastrointestinal nematodes in dromedary camels

The anthelmintic activity of ivermectin when administered orally and subcutaneously at a dosage of 0.2 mg/kg of body weight was evaluated in 4 trials involving 20 dromedary camels (Camelus dromedarius). Fecal egg counts were made on the day of treatment and at 2, 4, and 10 weeks after treatment. Trichostrongylid egg counts were reduced by a maximum of 100% when ivermectin was administered orally and by greater than 88% when given subcutaneously. Egg counts of Trichuris spp were reduced by greater than 85% with oral administration, but increased following subcutaneous treatment. No adverse local or systemic reactions were observed following treatment with ivermectin by either route.     

The relationships between the internal and external pelvic measurements of Schwartzbunt cows]

1118 Friesian cows and 101 Friesian heifers were investigated in internal pelvic measurements and their relationships to external measurements. The mean of the pelvic vertical and the medium diagonally diameter of the pelvis are 19.8 cm and 18.3 cm. 363.9 square centimetres and 76.3 centimetres were found for the pelvic surface and pelvic circumference. The difference between the biggest and smallest pelvis was 295.0 square centimetres. Medium to high coefficiences of correlation were detected between the internal pelvic measurements but relationships between internal and external pelvic measurements were low. From determined external pelvic measurements only the hip breadth provides usefull informations of the pelvic shape.     

Aetiological analysis and diagnosis of reproductive disorders in male dromedary camels

The purpose of this paper was to analyse the aetiology and methods of diagnosing reproductive disorders in male dromedary camels. Male camel infertility manifests as one of three conditions: post-coital infertility (IG), inability to copulate (IC) and lack of sexual desire (LSD). IG is mainly a testicular disorder that is linked to a deteriorated seminogram, arrested spermatogenesis, Sertoli cell-only syndrome and testicular degeneration. For IG diagnosis, semen analysis, testicular biopsy and fine-needle aspiration are gold standards. Testicular ultrasonography was generally inefficient. High serum FSH was found in IG camels with oligo- and azoospermia, implying primary spermatogenesis defects. The testis-expressed protein (TEX101) and the epididymis-expressed protein (ECM1) are reliable biomarkers for distinguishing between obstructive and non-obstructive azoospermia. IC manifests in two forms: phimosis (PHI) and erectile dysfunction (ED). PHI is frequently linked to preputial and penile pathologies, as well as leucocytosis, neutrophilia and elevated nitric oxide metabolites. The majority of camels with ED have normal genital organs, and the condition is associated with an increase in cardiac troponin I. LSD is a rare disorder brought on by hormonal imbalances, high temperatures, stress and debilitating diseases. In conclusion, IG diagnosis necessitates semen analysis, testicular biopsy or fine-needle aspiration, and FSH testing, whereas IC diagnosis requires preputial and penile examinations. Diagnostic aids include serum and seminal biomarkers.     

Pharmacokinetics of progesterone in dromedary camels (Camelus dromedarim)

The effect of ovariectomy or administration of progesterone (P4) on the disposition kinetics of P4 was determined in dromedary camels. The disappearance of P4 from peripheral circulation of the camel following ovariectomy or after a single intravenous (I.V.) injection of 1 mg kg(-1) body weight followed a bioexponential curve. Both curves were parallel indicating that the disappearance of injected P4 behaved similarly to endogenous P4. The mean (+/- SD) half-life calculated from the slower component of this decline, was 26.0 +/- 2.0 min after I.V. injection of P4 and 28.0 +/- 2.1 min after ovariectomy. The apparent volume of distribution (1370 ml kg(-1)) exceeded total body water suggesting extensive tissue penetration.     

Activity of some enzymes in the serum of dromedary camels.

The activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), acid phosphatase (ACP), lactate dehydrogenase (LDH) and isocitric dehydrogenase (ICD) in the serum of 60 healthy dromedary camels of either sex and different ages (one to 25 years) were determined. The results were analysed with respect to time of year (December-January and May-June), sex and age groups (below four years; four to 10 years; and over 10 years). The overall mean activities of AST, ALT, ALP, ACP, LDH and ICD were 36.1 +/- 0.35, 4.65 +/- 0.35, 27.21 +/- 0.43, 7.18 +/- 0.21, 479.0 +/- 7.33 and 7.74 +/- 0.17 iu litre-1, respectively. Activities of AST, ALT, ALP and ACP were significantly higher during extremely hot conditions (May-June) than in extreme cold (December-January) while the activity of LDH was higher in extremely cold conditions. Analysis of data based on sex revealed that AST, ALT and ALP activities in the serum of male animals were significantly higher than in female animals. The activities of all the enzymes were highest in animals under four years and then gradually decreased with age being lowest in the animals over 10 years.     

Inflammatory reactions in the teat and udder of the dry cow

The inflammatory reactions in the teat and udder of the dry cow were studied by total and differential somatic cell counts (SCC) and by measuring bovine serum albumin, N-acetyl-beta-D-glucosaminidase (NAGase), plasminogen and plasmin. The teat and udder cisterns were surgically separated from each other in two udder quarters of each cow. Salmonella endotoxin was infused in one teat cistern and one udder quarter, and saline was infused in one teat cistern and one udder quarter. The inflammatory response was followed by several samplings post infusion. The reactions in the dry udder quarters were mainly in line with the results of similar studies in lactating glands. The differential SCC and the NAGase results were, however, somewhat different. The teats were capable of a strong inflammatory response. Reactions different from those seen in the glands were observed with regard to permeability changes and NAGase. The experimental model used showed promising results and is suitable for further studies of the inflammatory process.     

Circadian rhythm of bone formation biomarkers in serum of dromedary camels

The circadian rhythm of biomarkers of bone formation including osteocalcin and bone alkaline phosphatase (BAP) was studied in the serum of dromedary camels. Blood samples were collected every 60 min for 24 h from 10 healthy adult female camels. ELISA was used to determine the concentrations of serum osteocalcin and BAP. The results showed a marked fluctuation in the concentration of osteocalcin during the 24 h period with minimum and maximum levels at 13:00 (01:00 pm) and 18:00 (06:00 pm), respectively. Slight fluctuation was observed in the concentration of BAP with minimum and maximum levels at 01:00 am and 12:00 pm, respectively. The correlation between the two biomarkers was weak. It was concluded that it is important to fix the time of blood sampling for analysis of osteocalcin concentrations, but not for BAP.     

Pharmacokinetics and intramuscular bioavailability of difloxacin in dromedary camels (Camelus dromedarius)

Single-dose disposition kinetics of difloxacin (5mg/kg bodyweight) were determined in clinically normal male dromedary camels (n=6) following intravenous (IV) and intramuscular (IM) administration. Difloxacin concentrations were determined by high performance liquid chromatography with fluorescence detection. The concentration-time data were analysed by compartmental and non-compartmental kinetic methods. Following a single IV injection, the plasma difloxacin concentration-time curve was best described by a two-compartment open model, with a distribution half-life (t(1/2alpha)) of 0.22+/-0.02h and an elimination half-life (t(1/2beta)) of 2.97+/-0.31h. Steady-state volume of distribution (V(dss)) and total body clearance (Cl(tot)) were 1.02+/-0.21L/kg and 0.24+/-0.07L/kg/h, respectively. Following IM administration, the absorption half-life (t(1)(/)(2ab)) and the mean absorption time (MAT) were 0.44+/-0.03h and 1.53+/-0.22h, respectively. The peak plasma concentration (C(max)) of 2.84+/-0.34microg/mL was achieved at 1.42+/-0.21h. The elimination half-life (t(1/2el)) and the mean residence time (MRT) was 3.46+/-0.42h and 5.61+/-0.23h, respectively. The in vitro plasma protein binding of difloxacin ranged from 28-43% and the absolute bioavailability following IM administration was 93.51+/-11.63%. Difloxacin could be useful for the treatment of bacterial infections in camels that are sensitive to this drug.     

Spatial association between primary Middle East respiratory syndrome coronavirus infection and exposure to dromedary camels in Saudi Arabia

Middle East respiratory syndrome coronavirus (MERS‐CoV) is an emerging zoonotic disease. Exposure to dromedary camels (Camelus dromedaries) has been consistently considered the main source of primary human infection. Although Saudi Arabia reports the highest rate of human MERS‐CoV infection and has one of the largest populations of dromedary camels worldwide, their spatial association has not yet been investigated. Thus, this study aimed to examine the correlation between the spatial distribution of primary MERS‐CoV cases with or without a history of camel exposure reported between 2012 and 2019 and dromedary camels at the provincial level in Saudi Arabia. In most provinces, a high proportion of older men develop infections after exposure to camels. Primary human infections during spring and winter were highest in provinces characterized by seasonal breeding and calving, increased camel mobilization and camel–human interactions. A strong and significant association was found between the total number of dromedary camels and the numbers of primary camel‐exposed and non‐exposed MERS‐CoV cases. Furthermore, spatial correlations between MERS‐CoV cases and camel sex, age and dairy status were significant. Via a cluster analysis, we identified Riyadh, Makkah and Eastern provinces as having the most primary MERS‐CoV cases and the highest number of camels. Transmission of MERS‐CoV from camels to humans occurs in most primary cases, but there is still a high proportion of primary infections with an ambiguous link to camels. The results from this study include significant correlations between primary MERS‐CoV cases and camel populations in all provinces, regardless of camel exposure history. This supports the hypothesis of the role of an asymptomatic human carrier or, less likely, an unknown animal host that has direct contact with both infected camels and humans. In this study, we performed a preliminary risk assessment of prioritization measures to control the transmission of infection from camels to humans.     

Composition and electrophoretic mobility of plasma lipoproteins of dromedary camels (Camelus dromedarius)

OBJECTIVE: To determine the lipid composition and electrophoretic pattern of plasma lipoproteins in samples obtained from healthy 1-humped camels (Camelus dromedarius). ANIMALS: 34 healthy camels raised under similar farming and dietary conditions. PROCEDURES: Plasma samples were subjected to density-gradient ultracentrifugation for separation of plasma lipoproteins, including very-low-density lipoproteins (VLDL), low-density lipoproteins (LDL), and high-density lipoproteins (HDL). Purity of the separation was assessed by use of polyacrylamide gel disk electrophoresis. Concentrations of triglycerides, cholesterol, and phospholipids were measured in each lipoprotein fraction, and lipoprotein electrophoretic patterns were determined in plasma samples. RESULTS: Phospholipid was the major constituent of VLDL (mean +/- SD concentration, 10.62 +/- 1.2 mg/dL), LDL (24.66 +/- 3.12 mg/dL), and HDL (38.08 +/- 0.76 mg/dL). Low-density lipoprotein, VLDL, and HDL were important plasma lipoprotein carriers for cholesterol (67.94 +/- 9.51%), triglyceride (55.83 +/- 7.81%), and phospholipid (51.91 +/- 1.55%), respectively. On the basis of electrophoresis results, relative percentages of alpha- and beta-lipoproteins were 31.72 +/- 4.88% and 68.3 +/- 4.68%, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: The lipoprotein profile in 1-humped camels differed substantially from that of other ruminants. Results may be useful in the evaluation of metabolic disorders in camels.     

Ovary and ovarian bursa in dromedary camels: Clinical relevance of the topographical features

This study aimed to associate ovarian characteristics with the efficiency of clinical examination and occurrence of genital diseases in dromedary camels. The reproductive tract of 870 female camels was examined through standard transrectal palpation and by ultrasonography during the breeding season. The ovaries were examined for structures and dimensions. The follicles were categorized according to size, the thickness of the wall and contents. Follicle aspiration was carried out from females with overgrown follicles (OVGF, n = 127), and the obtained follicular fluids were examined. At the slaughterhouse, 100 genital tracts were examined in situ and after dissection. Ovarian bursae were examined for patency and the presence of fluid (ovarian hydrobursitis, OVHB). Risks associated with the development of OVGF and OVHB were identified by the logistic regression. The results showed that, due to topographical difference, the right ovary was more accessible at rectal palpation than the left ovary (98.9% vs. 96.1%, p = .0005). Time needed for rectal palpation of the right ovary was shorter than the left ovary (25.1 ± 25 s vs. 34.6 ± 34.5 s, p = .03). Significant relationships were found between OVGF and OVHB (Odds ratio = 10.5, p = .001), OVGF and clinical endometritis (Odds ratio = 21.1, p = .001), OVGF and vaginal adhesion (Odds ratio = 4.4, p = .03), and OVHB and clinical endometritis (Odds ratio = 11.3, p = .001). Ultrasonographic examination was imperative for the differentiation between active corpus luteum, old non-active corpus luteum and small luteinized follicle. In conclusion, anatomical arrangement of the ovary and ovarian bursa in dromedary camels affects the likelihood of their accessibility during clinical examination and predisposes to unusual genital disorders.     

Molecular detection of brucellosis in dromedary camels of Qatar by real-time PCR technique

Background and methodologyBrucellosis in livestock causes huge economic loses of developing countries and demonstrates a serious health risks to the patrons of infected dairy goods and meat. Prevention of brucellosis in cattle relies on the trustworthiness of the techniques utilized to detect the causative pathogen. In the current investigation, we described the exploration of the well-known real-time PCR technique based on the Brucella-specific IS711 with different tissue samples of dromedary camels in Qatar.ResultsThe findings of the real-time PCR unveiled the occurrence of Brucella spp in 60 % of lung tissues, 71.42 % of liver tissues, 72 % of spleen tissues, 25 % of kidney tissues, and 42.42 % of placental fluid samples. Among them, the liver tissues and spleen tissues possessed the highest number of positive results, whereas kidney tissues displayed the lowest number of positive results for Brucella spp.ConclusionThe findings of this investigation discloses that PCR technique is a sensitive and specific technique for the identification of Brucella spp. in dromedary camels. Most of the tissues samples showed the presence of Brucella spp. and also we concluded that there is a need for further studies to be conducted in order to identify specific species of Brucella.