Encephalopathy caused by Talisia esculenta intoxication in pregnant ewes and their newborn lambs

An outbreak of acute encephalopathy occurred in pregnant ewes and their newborn lambs associated with consumption of Talisia esculenta fruits and bark. Clinical signs in 5 adult pregnant ewes included drooling, bloat, tachypnea, depression, ataxia, body shaking, difficulty in rising, and recumbency. Three neonatal lambs born to some of those ewes had similar clinical signs. No significant gross abnormalities were observed on autopsy. Histologically, neuronal necrosis, axonal and dendritic swelling, and loss of Purkinje neurons were observed in the cerebellum. The observation of similar neurologic clinical signs and lesions in pregnant ewes and their neonatal lambs suggests that the toxic principle of T. esculenta crosses the placenta and reaches the fetus.

Streptococcus pneumoniae serotype 22F infection in respiratory syncytial virus infected neonatal lambs enhances morbidity

Respiratory syncytial virus (RSV) is the primary cause of viral bronchiolitis resulting in hospitalization and a frequent cause of secondary respiratory bacterial infection, especially by Streptococcus pneumoniae (Spn) in infants. While murine studies have demonstrated enhanced morbidity during a viral/bacterial co-infection, human meta-studies have conflicting results. Moreover, little knowledge about the pathogenesis of emerging Spn serotype 22F, especially the co-pathologies between RSV and Spn, is known. Here, colostrum-deprived neonate lambs were divided into four groups. Two of the groups were nebulized with RSV M37, and the other two groups were mock nebulized. At day three post-RSV infection, one RSV group (RSV/Spn) and one mock-nebulized group (Spn only) were inoculated with Spn intratracheally. At day six post-RSV infection, bacterial/viral loads were assessed along with histopathology and correlated with clinical symptoms. Lambs dually infected with RSV/Spn trended with higher RSV titers, but lower Spn. Additionally, lung lesions were observed to be more frequent in the RSV/Spn group characterized by increased interalveolar wall thickness accompanied by neutrophil and lymphocyte infiltration and higher myeloperoxidase. Despite lower Spn in lungs, co-infected lambs had more significant morbidity and histopathology, which correlated with a different cytokine response. Thus, enhanced disease severity during dual infection may be due to lesion development and altered immune responses rather than bacterial counts.

Soil-borne Septicaemic Colibacillosis in Neonatal Lambs: Salient Observations

Background: In sheep, Escherichia coli infection can occur as asymptomatic entity to septicaemic episode. Chiefly, it causes heavy mortality in lambs and devastates the farm economy. With an objective of documenting the salient epidemiological and clinico-pathological observations in this naturally occurred outbreak of septicaemic colibacillosis, this communication is made herewith. Methods: In February 2019, sudden death in lambs was observed in three flocks of sheep. Carcasses were subjected for necropsy and histopathological examination. Swab samples from heart, abomasum, intestines, liver and lung were examined for bacteriological and molecular confirmation. Result: The mean (±SE) age of lambs that were affected was 11.00 ±0.49 days (n=404). Lambs of native Malpura breed (87.5%) and other two crossbred sheep were affected. Overall mortality of lambs was 23.76%. Gross pathological observations were pulmonary edema, ecchymotic lesions in lungs, congestion in kidney and liver and presence soil-mixed ingesta in abomasum. From the morbid materials including stomach and intestinal swabs, 45 E. coli isolates were identified and they were also confirmed on polymerase chain reaction (PCR). Consequently, virulence genes for shiga toxin (stx2) and intimin (eae) were identified from the isolates. Although antibiotics were administered, only probiotics could control the new infection rate.

Passive immunity in lambs: Colostral and serum γ-glutamyltransferase as a predictor of IgG concentration and related to the diseases from birth to 12 weeks of life

The main goal of this study was to find a link between colostrum and the 1-day-old lamb serum γ-glutamyltransferase (GGT) activity and immunoglobulin G (IgG) concentration and their relation with neonatal diseases and beyond. Further, to set a linear relationship between the serum GGT activity (SGGTA) and the IgG concentration (SIgGC) in different days of the neonatal period, thereby determining the feasibility of the GGT activity in the prediction of the colostrum quality and passive immunity and to define a cut-off point for the SGGTA associated with an increased risk of illness or death in lambs. For this purpose, blood samples were obtained from the lambs before the colostrum intake (day 0) and on different days (1, 2, 4, 7, 14 and 28) in the neonatal period. The colostrum was collected from the respective ewes (n = 254) related to the lambs. The most accurate (R² = 0.652) model for predicting the SIgGC or passive immune status was the multiple regression model developed to calculate ln[IgG] from ln[GGT] in healthy neonatal lambs using the serum GGT and IgG values of day 0, 1, 2, 4, 7, 14 and 28. The In[GGT] activity at 24 h after birth in lambs that died or became ill during the neonatal period accounted for approximately 77% and 88% of the variation in the ln[IgG] concentration at 24 h after birth, respectively. The study revealed that SGGTA-24 > 500 IU may be considered as a critical cut-off point for the adequate colostral passive transfer. This study also disclosed that the colostral GGT activity might be used as an indicator to determine the colostrum quality.