The fascinating microbes and their impact on neonatal dogs and cats - A review

Recent literature data indicate that canine and feline neonates are not born in a sterile environment as it was stated previously. The acquisition, colonisation and maintenance of the early life microbiota of healthy fetuses is a rapidly developing research area. In humans, the natural healthy infant microbiome plays an essential role in health and its assembly is determined by the maternal-offspring exchanges of microbes. Even though this topic is becoming more and more important in dogs and cats, the exact role of the neonatal microbiome is not yet fully known in animals. This review summarises the current knowledge of the normal physiological neonatal microbiome in healthy puppies and kittens.

Canine Neonatal Assessment by Vitality Score, Amniotic Fluid, Urine, and Umbilical Cord Blood Analysis of Glucose, Lactate, and Cortisol: Possible Influence of Parturition Type?

Simple Summary

Parturition as a stressful event may influence puppies’ neonatal morbidity and mortality. The purpose of this study was to investigate the impact of parturition type on stress in newborn puppies, their weight gains, and survival in the first week postpartum. One hundred and twenty-three puppies were divided into three groups: vaginal parturition, emergency, and elective cesarean section. The Apgar score was assessed 5, 15, and 60 min postpartum, and samples of amniotic fluid, umbilical blood, and urine were collected for lactate, glucose, and cortisol concentration measurements. Although emergency cesarean section puppies had the highest cortisol concentration of all groups, their Apgar score at 5 min postpartum was comparable to the vaginal parturition group, which had the highest lactate levels. There were no significant differences between groups regarding relative growth rate. The type of parturition had no impact on puppies’ survival in our study, but supportive treatment was provided for non-vital puppies in stress. Non-invasive analysis of amniotic fluid and/or urine could help in the assessment of the neonatal vitality.

Abstract

The objective of this study was to investigate the impact of parturition type on vitality in newborn puppies, their weight gains, and survival in the first week postpartum. One hundred and twenty-three puppies were divided in three groups: vaginal parturition (VP), emergency (EM-CS), and elective cesarean section (EL-CS). Apgar scores were assessed 5, 15, and 60 min postpartum. Lactate and glucose concentrations were measured in amniotic fluid and umbilical blood; cortisol concentrations were measured in amniotic fluid and puppy urine. Puppies’ weight gain was tracked daily for 7 days postpartum. Apgar score at 5 and 15 min was significantly better in the VP group. EL-CS puppies had significantly lower umbilical blood and amniotic fluid lactate concentrations compared to the VP group, which also had higher umbilical blood lactate concentration than EM-CS puppies. The cortisol concentration in the amniotic fluid and in urine differed significantly between the groups, with the highest concentration in the EM-CS, followed by the VP group. Glucose concentration in amniotic fluid was higher in the VP group than EM-CS group. The type of parturition had no impact on puppies’ weight gain or their survival at birth; however, supportive treatment was provided for non-vital puppies. Non-invasive analysis of puppies’ fluids could help in the assessment of the neonatal vitality.

Macro- and microelements in serum and seminal plasma as biomarkers for bull sperm cryotolerance

Background

Wide variation in fertility rates is observed when using frozen bull semen, even when the bulls have met quality standards for semen production. Therefore, a simple and reliable test to assess the freezing potential of bull semen based on the analysis of fresh semen or blood would be of great value. Attention is now turning to assessment of seminal plasma components such as proteins and elements. In the present study, the concentrations of macro- and microelements in fresh bull semen plasma and in serum and their correlation with quality characteristics of fresh semen and with semen quality after freezing and thawing were determined. Ejaculates were collected from 30 mature bulls, and semen volume, concentration, sperm motility, morphology, tail membrane integrity, plasma membrane permeability and DNA fragmentation were determined on the day of collection and after freezing and thawing. The concentrations of macroelements (Na, Mg, K and Ca) and microelements (Cu, Fe, Zn and Se) were determined in the seminal plasma and serum. The semen samples were classified into satisfactory and unsatisfactory groups according to the fresh semen quality.

Results

Zinc and Se levels measured in serum were associated with almost all fresh and frozen-thawed semen quality characteristics, while Fe levels were associated only with acrosomal defects in fresh semen. Zinc and Fe levels in fresh seminal plasma were associated with various quality characteristics of fresh and frozen-thawed semen, while Se level in fresh seminal plasma was not associated with any of the semen quality characteristics.

Conclusions

Microelements were shown to be useful as biomarkers involved in the analysis of bull sperm quality and could be used as an additional tool to predict bull semen quality after freezing and thawing. Our results confirm that the analysis of Zn and Se levels in serum and Zn, Cu and Fe levels in fresh seminal plasma can provide information to discriminate between bull semen samples with spermatozoa with high or low cryotolerance.

Nitrosative Stress in the Frontal Cortex From Dogs With Canine Cognitive Dysfunction

Canine cognitive dysfunction (CCD) is an age-related disorder similar to human Alzheimer's disease (AD) that occurs in elderly dogs. Nitrosative stress has been implicated as one of the causes leading to neurodegenerative diseases, particularly AD. Its involvement in the development of CCD has not been studied so far. In the present study, immunohistochemical staining detected all three isoforms of nitric oxide synthases (nNOS, eNOS, and iNOS) and 3-nitrotyrosine (3-NT) in brains from CCD-affected dogs and non-demented control dogs in all layers of the canine frontal cortex. In CCD-affected and non-demented brains, nNOS was highly expressed in pyramidal-like neurons in the upper cortical layers. nNOS has also been observed in astrocytes in the CCD frontal cortex. The nNOS immunohistochemical staining was statistically significantly elevated in dogs with CCD in comparison to non-demented dogs. Blood vessel wall cells were positive for eNOS, which was also expressed in astrocytes and neurons. Intense 3-NT immunoreactivity was observed in the upper cortical layers, where amyloid-beta deposits spread in the last stage of CCD. Brain cells in the same area were highly immunoreactive for iNOS. This infers that neuroinflammation and nitrosative stress might exacerbate the neurodegenerative process in CCD-affected brains, ultimately leading to cognitive impairment.

Do newborn puppies have their own microbiota at birth? Influence of type of birth on newborn puppy microbiota

With recent research in humans, a hypothesis known as the sterile womb paradigm has been challenged. The objectives of this study were to determine the presence of placental and fetal microbiomes in dogs, the effect of different types of parturition on the fetal microbiome, and the effect that the fetal microbiome has on early puppy development. A total of 96 newborn puppies from 17 dams were included in the study. Puppies were divided into two groups depending on the type of parturition (vaginal birth (VB) or cesarean section (CS)). Immediately after birth, swabs of the placenta and meconium were taken. Swabs of the oral and vaginal mucosa of the dam were taken in the second half of the pregnancy and just before parturition. All samples were analyzed with a classical bacteriological examination, and bacterial colonies were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The weight gain of each puppy was tracked daily in the first 7 days postpartum. Bacteria from several different genera were isolated from 86.5% of meconium samples and 57% of placenta samples. While the meconium microbiota resembled bacteria from the maternal vagina in VB puppies, the meconium microbiota of puppies born by CS indicated a relative resemblance to maternal oral and vaginal microbiota. A statistically significant difference in the relative growth rate between puppies born by VB and CS was found (p < 0.05), with puppies born by VB gaining weight faster compared to the CS group. This difference was even more noticeable when VB puppies were compared to puppies born by elective CS. Puppies born without a detectable meconium or placental microbiota showed a slower growth rate than those with a meconium microbiota, regardless of the type of parturition (p < 0.05). The findings of this study provide new information about the placental microbiome in healthy pregnant dams and suggest intrauterine colonization of the fetus in dogs. It seems that the type of delivery and bacterial colonization might be an important consideration for the weight gain in puppies in the first few days of life.

Proteomic Analysis of Fresh and Liquid-Stored Boar Spermatozoa

In this study comparative proteomics was used to define changes in the expression of the spermatozoa proteins during liquid storage. Semen from eight boars was analyzed on the day of collection and after liquid preservation at 15-17 °C for three days. Sperm parameters (concentration, motility, morphology, vitality) and percentage of non-capacitated and acrosomal-reacted spermatozoa were determined. Sperm proteins were extracted and separated by two-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and proteomic profiles were computationally compared to highlight differentially expressed protein spots that were, in turn, identified by mass spectrometry. The intensities of four spots were significantly different between fresh and liquid stored sperm. Namely: ATP citrate lyase, chaperonin containing T-complex polypeptide 1 (TCP1) subunit ε and probable phospholipid-transporting ATP-ase were over-expressed in liquid stored sperm, whereas cytosolic non-specific dipeptidase was over-expressed in fresh sperm. These differentially expressed proteins could be used as plausible biomarkers for the evaluation of boar semen quality and spermatozoa survival after liquid storage and could help to address problems associated with sperm preservation.

Identification of the Identical Human Mutation in ACVR1 in 2 Cats With Fibrodysplasia Ossificans Progressiva

Two domestic shorthair cats, 1 intact female and 1 intact male, presented with progressive limb lameness and digital deformities at 4 and 6 months of age. Stiffness and swelling of the distal thoracic and pelvic limb joints progressed to involve hip and shoulder joints, resulting in reduced mobility. Radiographs in both cats and computed tomography of the male cat revealed ankylosing, polyarticular deposits of extracortical heterotopic bone spanning multiple axial and appendicular joints, extending into adjacent musculotendinous tissues. All findings supported fibrodysplasia ossificans progressiva (FOP), a disorder characterized by toe malformations and progressive heterotopic ossification in humans. In both cats, molecular analyses revealed the same heterozygous mutation in the activin A receptor type I (ACVR1) gene that occurs in humans with FOP. Several reports of heterotopic ossification in cats exist, but this is the first one to identify clinical FOP in 2 cats with the identical mutation that occurs in >95% of humans with FOP.

Staphylococcus pseudintermedius septicemia in puppies after elective cesarean section: confirmed transmission via dam's milk

Background

In humans, transmission of bacteria causing fatal sepsis in the neonates through mother’s milk has been reported. In dogs, it is believed that bacteria from canine milk are not the primary cause of neonatal infections. Staphylococcus pseudintermedius is colonizing the skin and mucocutaneous junctions in adult dogs and can act as an opportunistic pathogen. This bacterium was previously isolated from the canine milk and, although, its transmission from the dam’s milk to the newborn puppies causing a neonatal sepsis was suggested, this hypothesis has not been confirmed.

Case presentation

A 4.5-year-old healthy Boston terrier dam had an elective cesarean section, delivering five normal puppies and one dead runt. Next day, two puppies developed pustules on their legs and around the muzzle. After two more days, strings of blood were noticed in the stool of the biggest puppy that suddenly died later that night. The same day, blood became visible in the feces of all other puppies. Necropsy of the dead puppy revealed a distended abdomen, catarrhal gastroenteritis with lymphadenopathy, dark red and slightly firm lung, mild dilatation of the right heart chamber and congestion of the liver, spleen, pancreas and meninges. The thoracic cavity contained white-yellow slightly opaque exudate, and there was transudate in the abdominal cavity. Histopathology revealed an acute interstitial pneumonia and multifocal myocardial necrosis with mineralization. Bacteriology of the internal organs, body cavity effusions of the dead puppy and dam’s milk revealed a diffuse growth of S. pseudintermedius in pure culture. Whole genome sequencing (WGS) revealed that all isolates belonged to the sequence type 241 and differed in 2–5 single nucleotide polymorphisms; thus, the epidemiological link between the outbreak-associated isolates was confirmed.

Conclusions

This is the first report of a confirmed transmission of S. pseudintermedius through dam’s milk causing a neonatal sepsis in a puppy after an elective cesarean section. The epidemiological link between S. pseudintermedius isolates obtained from dam’s milk and internal organs of the affected puppy was confirmed by WGS. Our findings indicate that milk of healthy dams can serve as a reservoir of bacteria that can cause fatal sepsis in the newborn puppies.

Congenital peritoneopericardial diaphragmatic hernia in a family of Persian cats

Case series summary

The congenital midline defects of peritoneopericardial diaphragmatic hernia (PPDH) and omphalocele are believed to be related developmental defects, and have both been described in cats and dogs. This case series describes multiple cases of PPDH and omphalocele in related cats. The majority of cats affected with midline defects (PPDH or omphalocele) were male, consistent with previous reports of male overrepresentation.

Relevance and novel information

This is the first report of a family of Persian cats affected by PPDH and/or omphalocele. Clinical findings and pedigree information are suggestive of an autosomal recessive mode of inheritance. However, other modes of inheritance cannot be ruled out owing to limited sample size. The findings in this family and previous reports of Persians affected by PPDH warrant further investigation. Based on this information, recommendations for breeding populations of Persians and long-haired cats should include thoracic radiographs to screen for PPDH until a DNA-based genetic test is available.

The influence of macro- and microelements in seminal plasma on diluted boar sperm quality

Background

Growing evidence indicates that macro- and microelements in the seminal plasma of humans and various domestic animals are of great importance due to their roles in sperm metabolism, function, survival and oxidative stress. In the present study, we therefore determined the concentrations of macro- and microelements in fresh boar seminal plasma and their relation to sperm quality parameters after 3 days of liquid storage was assessed. Twenty ejaculates from eight boars were collected, and semen volume, concentration, sperm motility, morphology, tail membrane integrity, plasma membrane permeability, mitochondrial membrane potential and DNA fragmentation were determined on the day of collection (day 0) and day 3 (72 h) of storage at 15–17 °C. Seminal plasma was separated and the concentrations of macroelements (Na, K, Ca, and Mg) and microelements (Cu, Fe, Zn and Se) were determined.

Results

After 3 days of storage Se levels correlated significantly with sperm motility, progressive motility and morphology, all of which are routinely used for semen evaluation. On day 3, Se levels also correlated with tail membrane integrity, viability and intact DNA (P < 0.05). The correlation coefficients showed that mitochondrial function was better preserved at higher levels of Zn, while higher levels of Cu decreased mitochondrial function, but led to the better preservation of DNA. It was also evident that higher levels of Fe were associated with higher proportions of live spermatozoa and of spermatozoa with normal morphology after 3 days of storage (P < 0.05), while higher levels of Ca and Mg in fresh seminal plasma were associated with lower percentages of progressive motile spermatozoa and with a decreased proportion of spermatozoa with intact DNA (P < 0.05). Multivariate analysis including microelements showed that Se significantly affected sperm quality parameters, mentioned above, after 3 days of storage.

Conclusions

Macro- and microelements were associated with boar sperm quality and may be important biomarkers of boar sperm quality after liquid storage. Our results demonstrate that the evaluation of Se in fresh boar seminal plasma can serve as an additional tool in predicting sperm quality after storage.