Larval traits of the Caribbean amphidromous goby Sicydium punctatum (Gobioidei: Sicydiinae) in Guadeloupe

Amphidromous fish are the biggest contributor to the diversity of fish communities in river systems of Caribbean islands. Among them, Sicydium punctatum Perugia, 1896, which is endemic to the West Indies, represents the vast majority of fish in these rivers. The otolith microstructure and the biometry of S. punctatum postlarvae from Guadeloupe were investigated to explore the dispersal modalities of this species through an appreciation of the growth pattern, the pelagic larval duration (PLD) and the size‐at‐recruitment. The study was made on one cohort of 83 recruited postlarvae, fished at the Capesterre River's mouth on 2 November 2011. The mean (±SD) size‐at‐recruitment of the postlarvae was 24.6 ± 1.3 mm (range of 20.5–28.1 mm, n = 83). We found a mean (±SD) PLD of 72.2 ± 10.5 days (range of 54–101.5 days, n = 67). The growth rate estimated from the otolith increments showed a globally decreasing pattern during the marine larval phase. Growth rates at the beginning of the larval stage were significantly different between hatching periods, suggesting a relation between the hatching period and the growth rate in S. punctatum. This study adds on to the general understanding of the life cycle of S. punctatum in Guadeloupe that will help implement strategies to manage amphidromous fish populations in the Caribbean region.     

Genetic parameters estimates for ewes’ behavioural reactivity towards their litter after lambing

In livestock, improving maternal reactivity towards the litter is an important issue in breeding strategies to promote production and animal welfare. As of yet, no studies have investigated the within-breed genetic variation of maternal reactivity in sheep. The objective of this study was to estimate the genetic parameters of maternal reactivity traits. A total of 1,095 primiparous and 1,441 multiparous Romane ewes were phenotyped 24 hr postlambing using a behavioural test (arena test, AT) over a 10-year experimental period. The test consisted of three successive phases evaluating the ewe's attraction to her litter, reactivity to separation from her litter, and reactivity to a conflict between attraction to her litter and avoidance of a motionless human. The ewes were reared exclusively on rangelands (South of France) and lambed outdoors in the spring. High-pitched bleating and low-pitched bleating in the AT were mostly highly heritable (0.39‒0.46). Heritabilities were moderate for proximity to the litter in the presence of a human (0.27) and low for locomotion and vigilance in the AT (0.09‒0.15). The measurements of a given behaviour in the three phases of the AT were highly genetically correlated. Few genetic correlations were found between the different behavioural traits in the AT, the highest correlations being between high-pitched bleating and low-pitched bleating (−0.43 to −0.77). In conclusion, our findings demonstrate moderate-to-high heritability for maternal reactivity traits. These traits could be included in genetic selection schemes to enhance maternal attachment provided there is no unfavourable link with other production traits.     

Soundscapes reveal disturbance impacts: biophonic response to wildfire in the Sonoran Desert Sky Islands

Context

While remote sensing imagery is effective for quantifying land cover changes across large areas, its utility for directly assessing the response of animals to disturbance is limited. Soundscapes approaches—the recording and analysis of sounds in a landscape—could address this shortcoming.

Objectives

In 2011, a massive wildfire named “the Horseshoe 2 Burn” occurred in the Chiricahua National Monument, Arizona, USA. We evaluated the impact of this wildfire on acoustic activity of animal communities.

Methods

In 2013, soundscape recordings were collected over 9 months in 12 burned and 12 non-burned sites in four ecological systems. The seasonal and diel biological acoustic activity were described using the “Bioacoustic Index”, a detailed aural analysis of sound sources, and a new tool called “Sonic Timelapse Builder” (STLB).

Results

Seasonal biophony phenology showed a diurnal peak in June and a nocturnal peak in October in all ecological systems. On June mornings, acoustic activity was lower at burned than at non-burned sites in three of four ecological systems, due to a decreased abundance of cicadas directly impacted by the death of trees. Aural analyses revealed that 55% of recordings from non-burned sites contained insect sounds compared to 18% from burned sites. On October nights, orthopteran activity was more prevalent at some burned sites, possibly due to post-fire emergence of herbaceous.

Conclusions

Soundscape approaches can help address long-term conservation issues involving the responses of animal communities to wildfire. Acoustic methods can serve as a valuable complement to remote sensing for disturbance-based landscape management.

     

Immunohistochemical characterization of a hepatic neuroendocrine carcinoma in a cat.

A hepatic mass was identified in a 5-year-old, female mixed-breed cat that died spontaneously after a clinical history of progressive emaciation, ptyalism, and persistent coryza. At necropsy, a 7-cm-diameter, yellow-brown, firm, multilobulated tumor was identified in the liver. Microscopically, the mass consisted of neoplastic cells arranged in small, closely packed nests within a thin fibrovascular stroma. These cells were of medium sized and polygonal, with fine argyrophilic cytoplasmic granules. Nuclei were predominantly round with finely stippled chromatin and indistinct nucleoli. Mitotic figures were numerous. Immunohistochemically, most of the neoplastic cells were immunoreactive for chromogranin A, neuron-specific enolase (NSE), and cytokeratin AE1/AE3 and weakly labeled for synaptophysin. The tumor was negative for glial fibrillary acidic protein (GFAP), vimentin, and cytokeratins 5, 6, 8, and 17. Vascular emboli and intrahepatic micrometastasis were also identified with chromogranin A. All these features were consistent with a hepatic neuroendocrine carcinoma and emphasized the importance of using a panel of antibodies to diagnose such rare tumors.     

Ultrasonography of the omasum in cows with various gastrointestinal diseases

The omasums of 30 healthy cows and 55 cows with various gastrointestinal disorders (10 with left displacement and eight with right displacement of the abomasum, 10 with abomasal volvulus, 10 with traumatic reticuloperitonitis, nine with ileus of the small intestines and eight with reticulo-omasal stenosis) were examined ultrasonographically on the right side of the body with a 3.5 MHz linear transducer. The dorsal and ventral margins of the omasum and its size in the fifth to 11th intercostal spaces were determined. Generally, the ultrasonographic appearance of the omasum did not differ between the healthy and abnormal cows. The omasum appeared as a semicircle, and the omasal wall closest to the transducer was visible as a thick echogenic line. In a few of the abnormal cows, the omasal laminae were visible and the omasum appeared to have motility. In the cows with left and right displacement of the abomasum and abomasal volvulus, the dorsal margin of the omasum was significantly further from the dorsal midline in some intercostal spaces than in the healthy cows. In the cows with left displacement of the abomasum, the ventral margin of the omasum was significantly further from the dorsal midline in the 7th intercostal space than in the healthy cows. In the cows with reticulo-omasal stenosis, traumatic reticuloperitonitis and ileus of the small intestine, the ventral margin of the omasum was significantly closer to the dorsal midline in some intercostal spaces than in the healthy cows. The mean (sd) size of the omasum in the healthy cows varied from 16.3 (1.5) cm to 56.9 (10.0) cm, depending on the intercostal space, and the omasum was significantly smaller in some intercostal spaces in the cows with reticulo-omasal stenosis, right displacement of the omasum, abomasal volvulus and ileus of the small intestine.     

Blood gas and acid-base analysis of arterial blood in 57 newborn calves

The pH, partial pressure of oxygen (pO(2)), partial pressure of carbon dioxide (pCO(2)), concentration of bicarbonate (HCO(3)(-)), base excess and oxygen saturation (SO(2)) were measured in venous and arterial blood from 57 newborn calves from 55 dams. Blood samples were collected immediately after birth and 30 minutes, four, 12 and 24 hours later from a jugular vein and a caudal auricular artery. The mean (sd) pO(2) and SO(2) of arterial blood increased from 45.31 (16.02) mmHg and 64.16 (20.82) per cent at birth to a maximum of 71.89 (8.32) mmHg and 92.81 (2.32) per cent 12 hours after birth, respectively. During the same period, the arterial pCO(2) decreased from 57.31 (4.98) mmHg to 43.74 (4.75) mmHg. The correlation coefficients for arterial and venous blood were r=0.86 for pH, r=0.85 for base excess and r=0.76 for HCO(3)(-). The calves with a venous blood pH of less than 7.2 immediately after birth had significantly lower base excess and HCO(3)(-) concentrations for 30 minutes after birth than the calves with a venous blood pH of 7.2 or higher. In contrast, the arterial pO(2) was higher in the calves with a blood pH of less than 7.2 than in those with a higher pH for 30 minutes after birth.     

Ultrasonographic findings in 2 cows with duodenal obstruction

Two cases where clinical findings suggestive of proximal ileus resulting in hypokalemic and hypochloremic alkalosis are presented. Ultrasonographs showed distension of the sigmoid flexure along the ventral border of the liver and between the serosal lamellae of the greater omentum in the flank, allowing exact preoperative obstruction localization.