Effect of heat stress during the dry period on milk yield and reproductive performance of Holstein cows

This study aimed to determine the influence of heat stress during the dry period on milk yield and reproductive performance of Holstein cows in a hot environment. Breeding and milk production records of cows, as well as meteorological data between 2017 and 2020 from a commercial dairy herd (n = 12,102 lactations), were used to determine the relationship between climatic conditions during the dry period (average of the temperature-humidity index (THI) at the beginning, middle, and end of the dry period) and reproductive efficiency and milk yield traits. THI was divided into < 70 (no heat stress), 70-80 (moderate heat stress), and > 80 (severe heat stress). First-service pregnancy rate of cows decreased (P < 0.01) with increasing hyperthermia during the dry period (9.5, 7.3, and 3.4% for THI < 70, 70-80, and > 80, respectively). All-service pregnancy rate was highest (P < 0.01) for cows not undergoing heat stress during the dry period (60.2%) and lowest (42.6%) for cows with severe heat stress during the dry period. Cows not experiencing heat stress during the dry period required a mean ± SD of 5.6 ± 3.8 services per pregnancy compared with 6.5 ± 3.6 (P < 0.01) for cows subjected to THI > 80 during the dry period. Cows not suffering heat stress during the dry period produced more (P < 0.01) 305-day milk (10,926 ± 1206 kg) than cows subjected to moderate (10,799 ± 1254 kg) or severe (10,691 ± 1297 kg) heat stress during the dry period. Total milk yield did not differ (P > 0.10) between cows not undergoing heat stress (13,337 ± 3346 kg) and cows subjected to severe heat stress during the dry period (13,911 ± 4018 kg). It was concluded that environmental management of dry cows during hot months is warranted to maximize reproductive performance and milk yield in the following lactation.

Impact of the COVID-19 pandemic on electrophysiological procedures at a national referral center

Funding Acknowledgements

Type of funding sources: None.

Background - Introduction: The COVID-19 pandemic has generated serious repercussions on the health system, reducing the number of all cardiology procedures worldwide.

Objectives

Describe the impact of the COVID-19 pandemic on the procedures performed by the electrophysiology department in a national referral center. 

Methods

We made a retrospective review of our data base and we compared procedures made in the last 3 years since 2017 to 2019 with the procedures made in the 2020. We divide the procedures into two large groups: Cardiac Implantable Electronic Devices (CIED) related procedures (which included implants, revisions, changes, upgrades and extractions) and electrophysiological studies and ablations (which included conventional and complex procedures). Other types of procedures were no included.

Results

There was a significant reduction in all procedures, the average of procedures performed in the last 3 previous years was 467 (there were 479 in 2017, 411 in 2018 and 511 in 2019), while in 2020 we performed only 319 (p = 0.01); this represents a reduction of 33.4% in the total number of procedures performed in our center. There was no statistical difference regarding the CIED related procedures, the average of procedures of the last 3 previous years was 174 (there were 186 in 2017, 148 in 2018 and 188 in 2019), and in 2020 we performed 189 procedures, this value is near to the average of the last 3 previous years and very close to the value of the 2019 (p = 0.46).

Regarding the electrophysiological studies and ablations, the average of procedures of the last 3 previous years was 293 (there were 293 in 2017, 263 in 2018 and 323 in 2019), while in 2020 we performed only 129 procedures, considerably decreasing compared to the previous years (p &lt; 0.01). The reduction in the electrophysiological studies and ablations was 55.97%. The most affected months were April, May and June.

Conclusions

The COVID-19 pandemic considerably affected the number of electrophysiological procedures in our center, reducing it by 33.4% compared to the previous years. The reduction of procedures fundamentally affected the electrophysiological studies and ablations, reducing them by 55.97%. The number of CIED related procedures were no affected. Electrophysiological procedures Procedures2017201820192017-2019 average2020CIED related procedures186148188174189Electrophysiological studies and ablations293263323293129Total479411511467319Comparative table of the electrophysiological procedures performed in our center in recent years.Abstract Figure. Comparison of the procedures.

Influence of land use and climate on the load of suspended solids in catchments of Andean rivers

Understanding the interaction between anthropogenic land use and the rainfall pattern can be crucial to predict changes in total suspended solids (TSS) in streams and rivers. We assessed the effects of land use and annual rainfall on the TSS load of 19 southern Chilean catchments. The results indicated that the concentration of TSS increased in catchments with a rainy regime and greater annual precipitation. TSS load also increased as the surface of open areas increased at the catchment scale and decreased with increasing cover of glaciers and perennial snow. However, we did not find support for models with interaction terms between climate and land use. Results suggest that a regional decrease in annual rainfall accompanied by an increase in the altitude of the zero isotherms, as predicted by climate models, should have multiple effects on TSS. In particular, increased TSS load can be expected from a contraction of glaciers and perennial snow areas as well as the intensification of new crops and urban expansion.

Structural and Ultrastructural Study of the Intracranial Portion of the Oculomotor, Trochlear and Abducent Nerves in Dog

The right intracranial portion of the oculomotor, trochlear and abducent nerves were removed from six adult German shepherd dogs and analysed by light and electron microscopy. In all cases the nerve sectional area was calculated. Unmyelinated and myelinated fibres were analysed and number, diameter and cross-sectional area were calculated. In myelinated fibres, also calculated were the corresponding axon area and diameter, and myelin sheath thickness. The mean number of myelinated fibres was 8543.50 +/- 1231.85 being the unmyelinated 1402 +/- 241.58 in the oculomotor nerve; 1509 +/- 223.17 and 287.67 +/- 72.28 in the trochlear nerve and 2473.00 +/- 211.41 and 231.25 +/- 92.67 respectively in the abducent. The mean diameter was 10.23 +/- 0.68 microm in myelinated and 0.43 +/- 0.21 for unmyelinated in oculomotor nerve, 10.53 +/- 0.55 microm and 0.33 +/- 0.04 for the trochlear, and 10.45 +/- 1.27 microm and 0.47 +/- 0.09 in the abducent nerve respectively. This study reveals that oculomotor, trochlear and abducent nerves of the dog show structural and ultra-structural features similar to the same nerves in other species.

Acute pancreatitis in childhood

AIM

to evaluate etiological agents involved in acute pancreatitis in children, as well as clinical, laboratory and radiological findings and the illness clinical course.

PATIENTS AND METHODS

we reviewed the cases of acute pancreatitis diagnosed over the last 15 years. The criteria used for cases to be included were acute abdominal pain, elevated serum amylase levels and/or ultrasound abnormalities in the pancreatic area in conscious patients, and the last two criteria in unconscious patients.

RESULTS

thirty-one children were included (average age 7.9 years, range 2-15; 55% males). Infection and gallstones were the most common causes (19 and 16 %, respectively). In all, 9.7% of cases were drug-related (valproic acid, L-asparaginase, azathioprine combined with high doses of methylprednisolone); 6.5% were traumatic in origin and another 6.5% was due to systemic diseases. In 35.5 % no cause was found (idiopathic). The most frequent symptoms were abdominal pain (90%) and emesis (38%). Amylase serum levels were elevated in all patients. Abdominal ultrasound scans were abnormal in 64%, with an increase in the pancreatic area in 48% and hypoechogenicity in 51%. Seven cases required surgical treatment (22%). Seven children had acute pancreatitis, and three of them died as a result of shock unrelated to pancreatitis. Relapse of disease occurred in 19% of patients.

CONCLUSIONS

acute pancreatitis should always be considered in children with abdominal pain. There are a wide variety of etiological factors and in a high percentage of patients no underlying cause is found. Prognosis is variable owing to the heterogeneity of the clinical course of this illness in children.

Successful medical treatment of two patients with eosinophilic oesophagitis

BACKGROUND/PURPOSE

Significant oesophageal eosinophilia is associated with oesophagitis and gastroesophageal reflux (GER). Eosinophilic oesophagitis is a rare disease that causes thickening of the oesophageal wall, narrowing of the oesophageal lumen, and severe motor disturbance.

METHODS AND RESULTS

Two 12 yr-old patients with eosinophilic oesophagitis were studied prospectively. Clinical and investigation details are presented. Elemental formula was administered until complete remission of disease. Final outcome was assessed after 3 months on regular diet with exclusion of specific allergic components. Both patients responded to the dietary manipulation.

CONCLUSIONS

Eosinophilic oesophagitis must be included in the differential diagnosis when dealing with oesophageal strictures of unknown or unclear aetiology. Elimination diet therapy plays a crucial role in ameliorating the course of the illness. Blood eosinophilia correlates with therapeutic response and with improvement of the disease.

Kinematic characteristics of Andalusian, Arabian and Anglo-Arabian horses: a comparative study

The aim of this study was to compare the kinematic trot characteristics of three different breeds of horse: Andalusian (AN, n = 15), Arabian (AR, n = 7) and Anglo-Arabian (AA, n = 5) using standard computer-assisted videography (25 Hz). Linear, temporal and angular parameters in fore- and hind limbs were analysed in six randomly selected strides per horse. Normalised angle-time diagrams along the complete stride were obtained for all joints angles in each breed and specific kinematic characteristics were detected graphically. AA horses displayed longer swing durations in both limbs ans a shorter angular range of motion (ARM) in scapula and pelvis inclination and in shoulder, hip and forelimb retraction-protraction angles. At lift off, stifle and tarsal joint angles were more flexed. In general, only small differences were observed in AR horse kinematics when compared with the other 2 breeds. AN horses presented negative overtracking length, which was positive in AR and AA. In AN horses the elbow and carpal joints were more flexed at the moment of maximal elevation, elbow and fore-fetlock joints also exhibited a larger ARM due to a smaller angle at maximal flexion. In the hind limbs, tarsal, hind fetlock and retraction-protraction angles presented a larger ARM in AN horses due to greater maximal flexion in the tarsal and hind fetlock joints. Fore- and hind fetlocks were also more flexed in horses from this breed. In conclusion, differences between kinematic variables at the trot were observed in the three breeds studied here, mainly in forelimb joints. The most outstanding feature was the greater forelimb flexion recorded in AN horses than in the other breeds which is consistent with the elevated movements in this breed. In AA horses, the ARM of proximal joints involved in retraction protraction in both fore- and hind limbs was smaller. All the differences observed highlighted the idiosyncratic nature of the trot in each breed; this may influence the functional capacity of each breed.

Inter-breed differences in equine forelimb kinematics at the walk

Linear, temporal and angular biokinematic characteristics of the forelimb at the walk in different breeds were determined, highlighting inter-breed differences. Twenty-three healthy stallions were used: ten Andalusians (AN), seven Arabs (AR) and six Anglo-Arabs (AA). Height at the withers was significantly different between groups (P < 0.001). Six trials per horse were recorded using a levelled video camera (sampling frame rate 25 frames/s), digitized and analysed using a semi-automatic movement analysis system. No statistically significant differences in speeds were recorded between breeds (P > 0.05). The only temporal parameter which was similar in the three breeds was the moment at which the hoof reached the highest point in its trajectory. The variables presenting the most significant differences were the percentages of deceleration and propulsion within the stance phase. ANOVA for angular variables showed that the greatest difference was in the range of angular movement of the carpal joint, being higher in AN, due to a lower minimum value. In the fetlock joint, the greatest difference was observed in minimum values, which differed in all three breeds. Significant inter-breed differences were also observed for maximum limb retraction, being lowest in the AN group, followed by the AA and AR groups. This finding was reflected in the angular range of motion, despite smaller differences in the degree of limb protraction; very similar values were reported in all three breeds. As regards the elbow joint, no inter-breed differences were observed in terms of minimum values, whereas differences were recorded for maximum and angular range of motion, higher values being displayed by the AR and AN groups than by AA animals. In conclusion, inter-breed differences may be determined in equine forelimb biokinematics at the walk. This study distinguished between AN, AR and AA horses.

Continuous monitoring of oesophageal pH during general anaesthesia with laryngeal mask airway in children

We studied the incidence of gastro-oesophageal reflux (GOR) during general anaesthesia with the laryngeal mask airway (LMA) in a paediatric population with two ventilatory regimes: spontaneous breathing and controlled mechanical ventilation (CMV). Thirty children between 6 months and 15 years, ASA I-II, for routine surgery, were randomly assigned in two groups: spontaneous ventilation (n=14), and CMV (n=16). A pH probe was situated in the central third of the oesophagus. Some 66% of the patients breathing spontaneously had GOR episodes vs. 92% of the patients with CMV (P < 0,01). Reflux took place mainly after LMA removal (21% vs. 68%; P < 0,01) and in the Postanaesthetic Care Unit (PACU) (29% vs. 43%; P < 0,05). There was a high incidence of GOR during general anaesthesia and in the PACU in paediatric patients anaesthetized with the LMA. GOR episodes were significantly more evident in the CMV group, mainly after LMA removal, but without clinical significance.

Angular kinematic patterns of limbs in elite and riding horses at trot

Normal speed videography was used to determine the angular parameters of 28 Spanish Thoroughbreds at trot. Horses were divided into 3 groups: Group UT, comprising 9 animals (provided by the VII National Stud, Cordoba, Spain) which had undergone no specific training programme and which were hand led at the trot; Group T, formed by 19 horses considered to be highly bred and trained, and which were also hand led; and Group RT, comprising the same horses as the latter group but this time trotted by a rider. Each animal was filmed 6 times from the right-hand side, using a Hi8 (25 Hz) video camera. Angular parameters for fore- and hindlimb joints were measured in each stride from computer-grabbed frames and entered into a spreadsheet for calculation; parameters included maximum and minimum angles, range of motion, and angles at landing, lift off and maximum hoof height; the times at which maximum angle, minimum angle, lift off and maximum hoof height occurred were calculated as percentages of total stride duration. Stride velocity (mean [s.d.]) was 4.01 (0.62), 3.60 (0.34) and 3.07 (0.36) m/s for Groups UT, T and RT, respectively. Data were then compared between Groups UT-T and Groups T-RT. Compared with Group UT, horses from Group T featured a shorter stance percentage (P<0.001) in both fore- and hindlimbs. The range of motion in forelimbs was smaller (P<0.05), due to lower retraction (P<0.001); moreover, maximum retraction appeared earlier (P<0.05). Greater scapular inclination was in evidence (P<0.05) and the shoulder joint extended further (P<0.05). Fore- and hind fetlock joints revealed a relatively shorter hyperextension period during the stance phase (P<0.01). Compared with Group T, horses from Group RT had a longer stance percentage, with belated maximum retraction of the fore- and hindlimbs. The range of movement in scapular inclination was greater (P<0.05), due to a smaller minimum angle (P<0.01), and the shoulder joint flexed more (P<0.05). The elbow joint extended more and for longer during the stance phase. Initial extension of the hip joint (P<0.05) and tarsus (P<0.001) lasted longer. The carpal and fore and hind fetlock joints recorded relatively longer hyperextension times, in addition to greater hyperextension during the stance phase. The results from the present study suggest that rider-effect must be taken in consideration when well gaited horses are selected for dressage purposes.

The influence of speed and height at the withers on the kinematics of sound horses at the hand-led trot

The influence of speed and height at the withers on some biokinematic stride parameters (linear, temporal and angular) was measured in 15 Spanish Thoroughbreds (Andalusian Purebred) trotted hand-led along a track; analysis was made of the correlation between speed and height at the withers and of some biokinematic parameters of equine locomotion. Both height at the withers and speed were positively and significantly correlated to the linear parameters examined. Temporal parameters did not reveal a significant correlation with the height at the withers. The correlations with the angular parameters were variable, often being significant for both height at withers and speed, although in most cases the coefficient was relatively low, probably owing to the narrow ranges of speed and height at the withers and their low variability. It was concluded that horses at the hand-led trot tend to have low variability in speed during successive trials, although the speed at which they move does have a significant influence on both linear and temporal stride parameters, and also on several angular parameters, while height at the withers has a major effect on linear parameters but less on angular parameters, and does not affect the temporal parameters.

Kinematics in horses at the trot before and after an induced forelimb supporting lameness

The aim of this study was to analyse the biokinematic alterations caused by an induced lameness in the right forelimb of Dutch Warmblood (DWB) horses using a system of computer-aided normal videography. Five mature DWB were recorded with a videocamera (frame rate 1/25) from a lateral view before and after an induced lameness. Before videotaping, passive markers were placed on the skin, over easily identifiable anatomical references to determine the joint angles in the forelimb (always on the flexor side). Lameness was induced using special horseshoes. The lameness was evident at the trot and mild at walk. The images were analysed using a real time digitalising system combined with a previously designed spreadsheet. Linear, temporal and angular parameters (maximum, minimum and angular range of motion) along the stride were calculated as well as the moments of highest extension (Pmax) and flexion (Pmin), expressed as a percentage of the whole stride. Results before and after the induced lameness were compared by a paired Student's t test at a significance level of P<0.05. No differences in speeds before and after the induced lameness were found. Stride length was significantly shorter in the lameness condition. Stride duration was slightly shorter in lameness. The diagonal stance phase increased, while the swing phase decreased. Angular parameters changed mainly in elbow, carpus, fetlock and retraction-protraction angles. This indicated that the angular range of motion in the elbow and carpal joints decreased, and the elbow Pmin occurred later in the stride. The results are useful in the development of video-based equine lameness diagnostics.

Safety and immunogenicity of an inactivated hepatitis A vaccine in children 2 to 5 years old

The reactogenicity and immunogenicity of an inactivated hepatitis A vaccine were assessed. Seventy healthy children aged between 2 and 5 years old, who lacked antibodies against the hepatitis A virus, were enrolled in this study. With a 0-, 1-, and 6-month vaccination schedule, the children received three doses of 360 enzyme-linked immunosorbent assay (ELISA) units of hepatitis A vaccine intramuscularly (deltoid). Safety parameters were recorded in standardized diary cards by the parents on the day of injection and the three following days. Blood tests for liver enzymes and anti-hepatitis A virus antibody analyses were performed the day of screening and 1, 2, 6 and 7 months after the first dose. Anti-hepatitis A virus antibody was tested by ELISA. Titres < 20 mIU/ml were considered negative. For the three hepatitis A vaccine doses administered, 22% (46/210) of the diary cards reported any kinds of signs or symptoms. Soreness at the injection site (9%, 18/210) and malaise (6%, 12/210) were the most common local and systemic reactions reported, respectively. The seroconversion rates were 83, 99 and 100% one month after the 1st, 2nd, and 3rd doses, respectively. The corresponding geometric mean titres were 124, 352, and 2,778 mIU/ml. We conclude that this HAV vaccine is safe and immunogenic in healthy children. As the hepatitis A epidemiology pattern is rapidly changing in our country (and other regions), resulting in an increasing population of susceptible adolescents and young adults, we suggest that the routine vaccination against hepatitis A in pre-school children attending day-care centres should be seriously considered.

[Histochemical and morphometric characteristics of some extraocular muscles of the dog]

This investigation was carried out on retractor bulbi, lateral and medial rectus muscles of six adult dogs. Tissues were collected from near the center of individual muscle bellies. These were stained for m-ATPase at varying pHs during preincubation, NADH-TR, Alpha-GPDH, Modified Mason trichrome and Hematoxyline and Eosin. Muscle fibers were classified as type I and type II, based on their reaction for m-ATPase. The retractor bulbi muscle was composed entirely of type II, oxidative, muscle fibers, with no glycolytic fibers. The rectus muscles presented a stratified composition, with superficial muscle fiber bundles containing a mixture of type II fibers oxidative and glycolytic, and central bundles of type I, mixed with type II. It was observed that there was less interstitial tissue in the center of the muscle bellies. Large diameter nerve fibers were also observed in the central layers.

Changes in cross-sectional area and capillary supply of the muscle fiber population in equine gluteus medius muscle as a function of sampling depth

The right and left gluteus medius muscles of 4 mature Andalusian stallions were examined by repeated needle biopsy over a specific area and depth, as well as at different depths, to determine whether the cross-sectional area and capillary supply of the various fiber types are homogeneous throughout the muscle. The muscle biopsy specimens were histochemically analyzed for fiber types (myofibrillar adenosine triphosphatase) and capillaries (amylase-periodic acid-Schiff method). Differences between contralateral sites were not identifiable for any of the analyzed variables. Differences between sampling depths were larger than those between sample sites. The percentage of type-1 fibers increased, and that of type-2B fibers decreased as a function of increased sampling depth, but the relative frequency of type-2A fibers did not change with depth. The mean cross-sectional area of type-1 and type-2A fibers increased significantly, and that of type-2B fibers decreased between the most superficial and the deepest sampling sites. The capillary density and the mean number of capillaries per fiber increased as a function of sampling depth, but significant changes were not recorded between sampling depths for overall mean fiber area. The mean number of capillaries in contact with fibers of each histochemical type increased significantly with increasing sampling depth only for type-1 fibers. However, the number of capillaries in contact with fibers changed significantly, relative to the fiber area, as a function of sampling depth; for type-2B fibers this variable increased, whereas for type-2A and type-1 fibers, it decreased.(ABSTRACT TRUNCATED AT 250 WORDS)

A seroepidemiologic study of hepatitis A in Spanish children. Relationship of prevalence to age and socio-environmental factors

Three child population groups from the Madrid area were studied for anti-HAV antibodies. Analysis was carried out with respect to age and socio-environmental factors. The population understudy was composed of 156 children, with ages ranging from 1 to 14 years; they were stratified in three socio-environmental groups (white-family unit, gypsy-family unit and orphanage), and also divided into subgroups according to age. As a whole, an age-related increase in prevalence was found. The overall seroprevalence by socio-environmental groups was: gypsy-family unit 63%, orphanage 46%, and white-family unit 23%. Significant differences between groups appeared from seven years on, being more marked among the eldest subgroups. Among the factors evaluated, hygienic-sanitary conditions and overcrowding influenced the high prevalence rate found in the gypsy-family unit subjects, whereas overcrowding appeared to be responsible for the higher prevalence in orphanage residents, as compared to white-family unit children.

Dietary interaction of cane molasses with source of roughage: intake and lactation effects

Effects of cane molasses at 0, 4, and 8% of DM in complete mixed diets were evaluated when molasses was fed to lactating dairy cows with cottonseed hulls, alfalfa haylage, or both combined. Thirty-six mature Holstein cows from mid to late lactation were used in a partially balanced incomplete block design with three 28-d periods. Variables measured were DM intake, milk yield, and composition. With cottonseed hull diets (30% of DM), molasses improved milk yield, milk fat percentage, solids-corrected milk, and feed efficiency. Dry matter intake was not affected by molasses. With alfalfa haylage diets (35% of DM), 8% molasses depressed actual milk yield and solids-corrected milk, DM intake, milk fat percentage, milk protein percentage, and feed efficiency. Milk fat percentage was increased with 4% molasses. With 65% alfalfa haylage diets, most variables measured were unaffected by molasses; however, with 8% molasses, DM intake increased and milk protein percentage decreased. In diets with both roughages combined, molasses did not affect any variable measured; however, these diets gave highest solids-corrected milk yields. Results show clearly that molasses effects depend on percentage molasses and type and amount of roughage in the diet.

[Effect of mechlorethamine in idiopathic nephrotic syndrome in childhood]

Mechlorethamine has been assessed in 28 patients with idiopathic nephrotic syndrome previously treated with prednisone only. One patient was cortico-resistant (CR), 22 cortico-dependent (CD) and 5 patients had frequent relapses (FR). FR patients had not histological examination and CR patient had a global focal sclerosis (GFS). Among CD patients, 12 had minimal change nephropathy (MCN) and 10 had a diffuse mesangial proliferation (DMP). After prednisone treatment was started, 0.1 mg/kg/d of mechlorethamine for four days was administered iv, in hospital and repeated one month later. After mechlorethamine treatment, GFS evolution was unchanged. Among FR, all the patients improved, 3 with complete remission and 2 with infrequent relapses. MNC improved in 66.6% and DMP in 40%, with the best evolution in immunofluorescence negative patients. Among early side effects, we found gastrointestinal disorders in 11 cases (39.2%) and leukopenia in 8 (28.2%), that required discontinuation of treatment in only 2 cases. We have not assessed gonadal toxicity. We comment the evolution after treatment of the different histological patterns, comparing with other nitrogen mustards and we conclude that mechlorethamine is useful in FR and CD idiopathic nephrotic syndrome corresponding to MCN or DMP with negative inmunofluorescence. Results with other nitrogen mustards, especially chlorambucil, are better.