Ultrasonographic examination of the forestomachs and the abomasum in ruminal drinker calves

Background

The study investigated the ultrasonographic appearance of the reticulum, rumen, omasum and abomasum of calves with ruminal drinking syndrome.

Methods

In ten milk-fed calves with ruminal drinking syndrome the reticulum, rumen, omasum and abomasum were examined by ultrasonography using a 5-MHz linear transducer before, during and after the ingestion of milk.

Results

The reticulum could be imaged in eight of ten calves before feeding. The reticular wall appeared as an echoic line, similar to mature cattle, and reticular folds were seen in eight calves. The reticular content appeared as echoic heterogeneous fluid. Reticular contractions were biphasic with 1.0 ± 0.38 contractions per minute. The rumen had a mean wall thickness of 2.1 mm dorsally, 3.5 mm at the level of the longitudinal groove, and 3.2 mm ventrally. The ventral sac of the rumen of all calves contained echoic heterogeneous liquid. During feeding the milk entering the rumen could be seen as hyperechoic liquid in five calves. The omasum was seen on the right side as a crescent-shaped line medial to the liver in seven calves. Only the omasal wall closest to the transducer was seen as an echoic line with a mean thickness of 2.7 mm. The ultrasonographic appearance of the omasum did not change during or after feeding. The abomasum was seen immediately caudal to the xyphoid on both sides of the midline before feeding. The mean length at the ventral midline was 22.2 cm. The ingesta were heterogeneous in all calves and the abomasal folds were distinct in eight. The mean lateral expansion of the abomasum from the ventral midline to the left and right varied from 8.7 to 13.8 cm and from 4.3 to 11.3 cm. The milk entering the abomasum was observed in all calves, and signs of milk clotting were seen in all calves 15 minutes after feeding.

Conclusion

This study showed that ultrasonography is useful for detecting milk in the reticulum and rumen of calves with ruminal drinking syndrome.     

Exposure to a dog elicits different cardiovascular and behavioral effects in pregnant and lactating goats

Background

Heart rate and plasma cortisol concentration are often used in evaluation of physiological reactions to stress and fear, but arterial blood pressure is rarely measured in farm animals. Goats are prey animals and can be expected to react strongly to a predator, especially when they have kids. We hypothesized that exposure to a dog elicits a flight response during pregnancy and a fight response when goats have kids to defend. Arterial blood pressure and heart rate should increase in both these cases, due to a synchronized discharge of the sympathetic nervous system.

Methods

Seven goats were exposed to a dog for 15 minutes at 12 ± 3 days before, and again at 10 ± 1 days after, parturition. Arterial blood pressure, heart rate, and activity were registered by telemetry. Behavioral data were collected during 5 minute sessions, followed by blood samples obtained via intrajugular catheters. Plasma cortisol concentration was analyzed by radioimmunoassay.

Results

At the appearance of the dog, the mean arterial blood pressure of the goats increased from 90 ± 8 to 111 ± 8 mmHg (p < 0.001) during pregnancy and from 96 ± 8 to 108 ± 8 mmHg during lactation (p < 0.001). Heart rate did not change at dog exposure during lactation, but increased from 117 ± 6 to 126 ± 10 beats/min (p < 0.01) during pregnancy. Dog exposure resulted in plasma cortisol concentration increasing from 17 ± 1 to 43 ± 7 nmol/l (p < 0.01) during pregnancy and from 21 ± 1 to 49 ± 6 nmol/l (p < 0.01) during lactation. In response to the dog, goats vocalized at a higher frequency and started to ruminate later during lactation compared to pregnancy.

Conclusions

When goats were exposed to a dog during pregnancy, their heart rate, blood pressure, and plasma cortisol increased, in contrast to lactation when only their blood pressure and plasma cortisol increased. However, when they were lactating, goats vocalized more and started to ruminate later compared to when they were pregnant.     

Cardiovascular,endocrine and behavioural responses to suckling and permanent separation in goats

Background

Suckling can be a peaceful or vulnerable event for goats and kids, whereas, separation is suggested as stressful. The aim of this study was to investigate physiology and behaviour in these two different situations in dairy goats.

Methods

Four studies were performed with seven goats kept with their first-born kid in individual boxes. The goats were videotaped and heart rate and arterial blood pressure were recorded every minute by telemetry from parturition until 24 hours after separation. One to two days after parturition, Study 1 was performed with analyses of heart rate and blood pressure around a suckling. In Study 2, performed 3-5 days after parturition, blood sampling was done before, during and after suckling. Study 3 was performed 4-6 days post partum, with blood sampling before and after a permanent goat and kid separation. In addition, vocalisations were recorded after separation. Blood samples were obtained from a jugular vein catheter and analysed for plasma cortisol, β-endorphin, oxytocin, and vasopressin concentrations. Study 4 was performed during the first (N1) and second nights (N2) after parturition and the nights after Study 2 (N3) and 3 (N4). Heart rate, blood pressure and time spent lying down were recorded.

Results

The kids suckled 2 ± 0.2 times per hour and each suckling bout lasted 43 ± 15 s. In Study 1, heart rate and blood pressure did not change significantly during undisturbed suckling. In Study 2, plasma cortisol (P ≤ 0.05 during suckling and P ≤ 0.01 five minutes after suckling) and β-endorphin (P ≤ 0.05) concentrations increased during suckling, but oxytocin and vasopressin concentrations did not change. In Study 3, the goats and kids vocalised intensively during the first 20 minutes after separation, but the physiological variables were not affected. In Study 4, heart rate and arterial blood pressure declined gradually after parturition and were lowest during N4 (P ≤ 0.05) when the goats spent longer time lying down than during earlier nights (P ≤ 0.01 during N1 and N3 and P ≤ 0.05 during N2).

Conclusions

Suckling elevated plasma cortisol and β-endorphin concentrations in the goats. The intensive vocalisation in the goats after separation, earlier suggested to indicate stress, was not accompanied by cardiovascular or endocrine responses.     

T-cell lymphoma in the nasal cavity of a Brown Swiss heifer

Background

Tumours of the upper respiratory tract are relatively common in cattle, but to our knowledge, there have been no reports of lymphoma of the nasal cavity. This case report describes the findings in a 22-month-old Brown Swiss heifer with T-cell lymphoma of the nasal cavity.

Case presentation

The main clinical findings were lacrimation and swelling of the head above and below the right eye, mild exophthalmos, third eyelid prolapse, purulent ocular discharge and congestion of scleral blood vessels. An endoscope could only be introduced a few centimetres into the right nasal cavity because of an obstructing mass in the nasal passage. Radiographs showed a mass in the right nasal cavity and maxillary sinus. A tentative diagnosis of neoplasia of the right nasal cavity was made and the heifer was euthanased and necropsied. A firm, tan mass measuring 10 by 13 by 15 cm in the right half of the head occupied the entire right nasal cavity. A final diagnosis of high-grade, malignant, small-sized T-cell lymphoma was made based on histological and immunohistochemical evaluation. A distinction between αβ T-cell or γδ T-cell lymphoma was not made.

Conclusions

This report on T-cell lymphoma in the nasal cavity of a cow suggests that nasal lymphoma should be included in the list of differential diagnosis of conditions associated with dyspnoea and stertorous breathing in cattle.     

Temperature regulation in horses during exercise and recovery in a cool environment

Background

Clipping the winter coat in horses is done to improve heat dissipation during exercise and make grooming easier. It is often combined with blanketing to keep the horse warm. The aims of the present study were to investigate how clipping and the use of blankets affect thermoregulation during exercise and recovery in horses.

Methods

One Gotland pony, one New Forest pony, and one warm-blooded horse exercised one after the other on a 6450 m long track. The horses walked, trotted and cantered according to a predetermined scheme, which took about 50 minutes including three stops. The scheme was repeated on five consecutive days when horses were: 1) unclipped 2) unclipped + blanket during recovery, 3) left or right side clipped, 4) clipped, and 5) clipped + riding blanket + blanket during recovery. Heart rate (HR) was measured with telemetry, respiratory rate (RR) by counting flank contractions, skin temperatures by thermistor probes, and rectal temperature with a digital thermometer. Skin wetness (SW) was estimated by ocular inspection (dripping = 5, dry = 0).

Results

Mean outdoor temperature varied from -1.1 to - 8.7°C. HR increased progressively during exercise with no difference between treatments. Maximum RR was 77 ± 30 breaths/min (unclipped) and 49 ± 27 breaths/min (clipped). The lowest skin temperature was 17.5 ± 2.7°C in a hind leg during exercise, which increased to 34.5 ± 0.1°C during recovery. Rectal temperature was elevated during recovery in unclipped, but not in clipped horses and skin temperature at base of tail was elevated during recovery except in unclipped horses without blanket. Moisture after exercise scored 3.2 ± 0.8 in unclipped and zero in clipped horses.

Discussion and conclusion

Leg skin temperature initially dropped at onset of exercise in clipped horses, and then increased after about 30 minutes due to internal heat from the working muscles. These changes were not significant when clipped horses had riding blankets, whereas unclipped horses became overheated as judged from respiratory rate and elevated rectal temperature. Providing clipped horses with blankets dampened the changes in leg skin temperature during exercise.     

Stallion spermatozoa selected by single layer centrifugation are capable of fertilization after storage for up to 96?h at 6°C prior to artificial insemination

Background

One of the challenges faced by equine breeders is ensuring delivery of good quality semen doses for artificial insemination when the mare is due to ovulate. Single Layer Centrifugation (SLC) has been shown to select morphologically normal spermatozoa with intact chromatin and good progressive motility from the rest of the ejaculate, and to prolong the life of these selected spermatozoa in vitro. The objective of the present study was a proof of concept, to determine whether fertilizing ability was retained in SLC-selected spermatozoa during prolonged storage.

Findings

Sixteen mares were inseminated with SLC-selected sperm doses that had been cooled and stored at 6°C for 48 h, 72 h or 96 h. Embryos were identified in 11 mares by ultrasound examination 16–18 days after presumed ovulation.

Conclusion

SLC-selected stallion spermatozoa stored for up to 96 h are capable of fertilization.     

Effects of melatonin implantation on cashmere yield,fibre characteristics,duration of cashmere growth as well as growth and reproductive performance of Inner Mongolian cashmere goats

Background

Exogenous melatonin could induce cashmere growth. However, induced growth of cashmere fleece by melatonin implants cannot be combined with the typical growth, resulting in earlier shedding followed by another cycle of cashmere growth. To address this issue, we examine the effects on the cashmere yield, fibre characteristics, and the growth and reproductive performance of cashmere goats of planned administration of melatonin.

Methods

Eighteen half-sib, female goats were assigned to two treatments (n = 9) including a control and a treatment where melatonin (2 mg/kg BW) was implanted at the end of April and end of June. Cashmere growth and shedding were observed for approximately 1 year following implantation. Fibre samples were collected monthly to determine cumulative cashmere length. Initiation and cessation dates for cashmere growth as well as the rate of cashmere growth were calculated. Cashmere yield, weight gain of dam, kidding date, litter size, and birth weight were also recorded.

Results

Melatonin implantation increased cashmere yield by 34.5 % (control 553.7 g vs. melatonin 745.0 g; P < 0.01), cashmere length by 21.3 % (control 95.2 mm vs. melatonin 115.4 mm; P < 0.01), and decreased fibre diameter by 4.4 % (control 14.6 μm vs. melatonin 14.0 μm; P < 0.03). In melatonin-treated goats, the average initiation date was earlier than in control goats (May 18, 2013 vs. July 2, 2013; P < 0.01) but there was a similar cessation date (March 22, 2014 vs. March 27, 2014). Consequently, the duration of cashmere growth was longer in melatonin-treated goats than in control goats (307 vs.270 days; P < 0.01). The final BW, average daily gain, kidding date, litter size, and birth weight were not influenced by melatonin implantation.

Conclusions

These data indicate that melatonin implantation (2 mg/kg BW) on two occasions (late April and June) increased cashmere yield by combining the induced growth of cashmere fleece with the typical growth and decreased the fibre diameter without changing dam growth rate or reproductive performance.     

The preference for water nipples vs. water bowls in dairy goats

Background

Previous studies have reported that the design of the water dispensers can influence the water intake in farm animals. Horses and dairy cows seem to prefer to drink from an open surface whereas sheep and pigs apparently prefer water nipples, probably because of the worse water quality in water bowls. The aim of the present study was to examine the preference of dairy goats for water nipples or water bowls.

Methods

In each of the two experiments (exp. 1, dry goats, exp. 2 lactating goats), 42 dairy goats were allotted into 6 groups of 7 goats. In period 1, the goats had access to a water nipple. In period 2, they had access to a water bowl and in period 3 (preference test) they had access to both a water nipple and a water bowl. Water usage and wastage was recorded and water intake (water usage - water wastage) was calculated for each group for the two last days of each period. In experiment 2, water samples from each dispenser were analyzed for heterotrophy germs at 22°C, Escherichia coli and turbidity.

Results

Water usage was higher from water nipples than from water bowls both in experiment 1 (dry goats) and experiment 2 (lactating goats). There was however, no difference in water intake from water nipples and water bowls. In the preference test (period 3), the water intake tended to be higher from the water nipple than from the water bowl both for the dry goats (exp. 1) and lactating goats (exp. 2). Especially for the dry goats, the differences between groups were large. Turbidity and heterotrophy germs were much higher in the samples from the water bowls than from the water nipples.Water wastage from the water bowls was negligible compared to the water nipples. From the water nipples the water wastage was 30% and 23% of water usage for the dry and lactating goats respectively.

Conclusions

We conclude that type of water dispenser (nipple or bowl) was probably of minor importance for water intake in goats, but water bowls had a lower water quality.     

Treatment of canine generalized demodicosis associated with hyperadrenocorticism with spot-on moxidectin and imidacloprid

Background

Canine generalized demodicosis associated with hyperadrenocorticism is often problematic and might be intractable. The aim of this study was to report the efficacy of a weekly application of spot-on moxidectin/imidacloprid in dogs with hyperadrenocorticism and secondary generalized demodicosis.

Methods

Dogs with hyperadrenocorticism and secondary generalized demodicosis were included. The condition of hyperadrenocorticism was treated and stabilized with trilostane before and throughout the study period in all dogs.

Results

Average total live adult mite counts before treatment and after four, eight and 12 weeks of spot-on moxidectin/imidacloprid (2.5/10 mg/kg) applications were 20.1 ± 6.3 (range, 13–33), 0.5 ± 0.7 (range, 0–2; 6/11 were negative), 0.2 ± 0.4 (range, 0–1; 9/11 were negative), 0.2 ± 0.4 (range, 0–1; 9/11 were negative) and 0.1 ± 0.3 (range, 0–1; 10/11 were negative) respectively; this difference was significant (P < 0.001). Ten of 11 dogs (90.1%) achieved clinical remission, as demonstrated by the absence of demodectic mites at any life stage at monthly scrapings for eight consecutive weeks, and maintained remission throughout the 12-month follow-up period.

Conclusion

The weekly application of spot-on moxidectin/imidacloprid appeared to be effective and safe against generalized adult onset canine demodicosis associated with hyperadrenocorticism.     

Ultrasonographic evaluation of reticular motility during rest, eating, rumination and stress in 30 healthy cows

A 3.5 MHz linear transducer was used to assess the motility of the reticulum in 30 healthy, standing, non-sedated cows while they were at rest, eating, ruminating and under stress. The ultrasonographic examinations were made over periods of nine minutes and video recorded for analysis. The reticulum contracted in a biphasic pattern while the cows were resting, eating or stressed. The first contraction was incomplete and was followed by a period of incomplete relaxation. A complete second contraction occurred immediately afterwards, followed by an interval of complete relaxation and the return of the organ to its original position. When the cows were ruminating, a regurgitation contraction, which was incomplete, occurred immediately before the biphasic contraction. The number of reticular contractions in a nine-minute period was largest when the cows were eating (13.9 contractions, or approximately 1.5 per minute) and smallest when they were stressed (9.3 contractions, or approximately 1 per minute). The duration of the first reticular contraction was shortest during rumination (2.4 seconds) and longest when the cows were eating (3.0 seconds). The interval between two biphasic contractions was shortest when the cows were eating (31.6 seconds) and longest when they were stressed (53.8 seconds).     

Implementation of immunohistochemistry on frozen ear notch tissue samples in diagnosis of bovine viral diarrhea virus in persistently infected cattle

Background

Bovine viral diarrhea is a contagious disease of domestic and wild ruminants and one of the most economically important diseases in cattle. Bovine viral diarrhea virus belongs to the genus Pestivirus, within the family Flaviviridae. The identification and elimination of the persistently infected animals from herds is the initial step in the control and eradication programs. It is therefore necessary to have reliable methods for diagnosis of bovine viral diarrhea virus. One of those methods is immunohistochemistry. Immunohistochemistry on formalin fixed, paraffin embedded tissue is a routine technique in diagnosis of persistently infected cattle from ear notch tissue samples. However, such technique is inappropriate due to complicated tissue fixation process and it requires more days for preparation. On the contrary, immunohistochemistry on frozen tissue was usually applied on organs from dead animals. In this paper, for the first time, the imunohistochemistry on frozen ear notch tissue samples was described.

Findings

Seventeen ear notch tissue samples were obtained during the period 2008-2009 from persistently infected cattle. Samples were fixed in liquid nitrogen and stored on -20°C until testing. Ear notch tissue samples from all persistently infected cattle showed positive results with good section quality and possibility to determinate type of infected cells.

Conclusions

Although the number of samples was limited, this study indicated that immunohistochemistry on formalin fixed paraffin embedded tissue can be successfully replaced with immunohistochemistry on frozen ear notch tissue samples in diagnosis of persistently infected cattle.     

Nematode control in suckler beef cattle over their first two grazing seasons using a targeted selective treatment approach

Background

With concerns over the development of anthelmintic resistance in cattle nematode populations, we must re-examine our approach to nematode control in cattle. Targeted selective treatments (TST), whereby individual animals are treated instead of entire groups, are being investigated as an alternative. The study objective was to determine if anthelmintic usage could be reduced using a TST-based approach to nematode control in spring-born suckler beef cattle over their first and second grazing seasons (SGS) without affecting performance. In the first grazing season (FGS), 99 calves with an initial mean (s.d.) calf age and live weight on day 0 (June 28^th 2012) of 107 (23.1) days and 160 (32.5) kg, respectively, were used. The study commenced on day 0 when calves were randomised and allocated to one of two treatments; 1), standard treatment (control) and 2), TST. Control calves were treated subcutaneously with ivermectin on days 0, 41 and 82 in the FGS. All calves were treated with ivermectin on day 124 and housed on day 133. In the SGS, only heifer calves from the FGS were used and control heifers were treated with ivermectin on day 393. Animals were weighed, blood and faecal sampled every three weeks. The TST animals were treated with ivermectin if thresholds based on a combination of plasma pepsinogen concentrations, faecal egg count and/or the presence of Dictyocaulus viviparus larvae in faeces (FGS only) were reached.

Results

No TST calves reached the treatment threshold criteria in the FGS. The FGS average daily live weight gain (ADG ± s.e.m.) for control and TST group calves was 0.89 ± 0.02 kg and 0.94 ± 0.02 kg day⁻¹, respectively (P = 0.17). In the SGS, all heifers were treated with ivermectin on day 431 due to clinical signs of respiratory disease. The ADG for control and TST heifers from turnout on day 321 to day 431 was 0.90 ± 0.04 and 0.80 ± 0.04 kg day⁻¹, respectively (P = 0.03).

Conclusions

Spring-born FGS suckler beef calves require minimal anthelmintic treatment to maintain performance. In contrast, clinical parasitic disease may develop in the SGS unless appropriate anthelmintic treatment is provided.     

Morphometric Parameters of Peripheral Nerves in Calves Correlated with Conduction Velocity

Background

Peripheral nerve injuries are the most frequent neurologic disorder in cattle. So far, no physiologic values have been established for the motor nerve conduction velocity (mNCV) in this precocial species.

Objectives

The electrophysiologic and morphometric reference values of peripheral nerves in calves were determined. It was hypothesized that these parameters would correlate to the high degree of maturity in the first days of life in this species compared to other species.

Animals

Twenty‐six healthy calves were used in this study.

Methods

The mNCV of the radial and the sciatic/common peroneal nerve was measured in all 26 calves. Nerve biopsies from a group of 6 calves were taken to correlate the obtained electrophysiologic data with morphological parameters.

Results

The mean mNCV of the radial nerve was 48.3 ± 10.6 m/s, whereas the mean mNCV of the sciatic/peroneal nerve was with 83.8 ± 5.9 m/s significantly faster (P < .0001). The average fiber diameter was 8.40 ± 2.80 μm (range, 1.98–17.90 μm) and the average g‐ratio was 0.61 ± 0.04 SD.

Conclusion and Clinical Importance

The established reference values for mNCV in calves correlate well with the evaluated morphometric parameters. Attributable to their comparably fast mNCV and high fiber diameters, juvenile calves appear to be much more mature individuals than other mammals. Electrophysiologic characterization of peripheral nerve injury now is feasible in this species.     

Restricted nutrient intake does not alter serum-mediated measures of implant response in cell culture

Background

During nutritional stress, reduced intake may reduce the efficacy of anabolic implants. This study was conducted to evaluate basic cellular responses to a growth promotant implant at two intake levels.

Methods

Sixteen crossbred steers (293 ± 19.3 kg) were used to evaluate the impact of anabolic implants in either an adequate or a restricted nutritional state. Steers were trained to individual Calan gates, and then randomly assigned to 1 of 4 treatments in a 2 × 2 factorial arrangement. Treatments consisted of: presence or absence of an anabolic growth implant (Revalor-XS, 200 mg TBA and 40 mg estradiol; IMPLANT or CONTROL) and a moderate energy, pelleted, starting cattle diet fed at either 2.0 × or 1.0 × maintenance energy (NE_M) requirements (HIGH or LOW). Serum (d 0, 14, and 28) was used for application to bovine muscle satellite cells. After treatment with the serum (20% of total media) from the trial cattle, the satellite cells were incubated for 72 h. Protein abundance of myosin heavy chain (MHC), phosphorylated extracellular signal-related kinase (phospho-ERK), and phosphorylated mammalian target of rapamycin (phospho-mTOR) were analyzed to determine the effects of implant, intake, and their interaction (applied via the serum).

Results

Intake had no effect on MHC (P = 0.85) but IMPLANT increased (P < 0.01) MHC abundance vs. CONTROL. Implant status, intake status, and the interaction had no effect on the abundance of phospho-ERK (P ≥ 0.23). Implanting increased phospho-mTOR (P < 0.01) but there was no effect (P ≥ 0.51) of intake or intake × implant.

Conclusions

The nearly complete lack of interaction between implant and nutritional status indicates that the signaling molecules measured herein respond to implants and nutritional status independently. Furthermore, results suggest that the muscle hypertrophic effects of anabolic implants may not be mediated by circulating IGF-1.     

Applicability of major histocompatibility complex DRB1 alleles as markers to detect vertebrate hybridization: a case study from Iberian ibex × domestic goat in southern Spain

Background

Hybridization between closely related wild and domestic species is of great concern because it can alter the evolutionary integrity of the affected populations. The high allelic variability of Major Histocompatibility Complex (MHC) loci usually excludes them from being used in studies to detect hybridization events. However, if a) the parental species don’t share alleles, and b) one of the parental species possesses an exceptionally low number of alleles (to facilitate analysis), then even MHC loci have the potential to detect hybrids.

Results

By genotyping the exon2 of the MHC class II DRB1 locus, we were able to detect hybridization between domestic goats (Capra hircus) and free-ranging Iberian ibex (Capra pyrenaica hispanica) by molecular means.

Conclusions

This is the first documentation of a Capra pyrenaica × Capra hircus hybridization, which presented us the opportunity to test the applicability of MHC loci as new, simple, cost-effective, and time-saving approach to detect hybridization between wild species and their domesticated relatives, thus adding value to MHC genes role in animal conservation and management.     

Investigation of Chlamydiaceae in semen and cauda epididymidis and seroprevalence of Chlamydophila abortus in breeding bulls

Background

Reproductive disorders associated with chlamydial infection have been reported worldwide in cattle and there are indications of potential venereal transmission.

Methods

Semen samples from 21 dairy bulls and cauda epididymidis tissue samples from 43 beef bulls were analysed for chlamydial agent by real-time polymerase chain reaction (PCR) including an internal amplification control (mimic). Additionally, presence of antibodies against Chlamydophila (Cp.) abortus among the bulls was investigated with the commercial Pourquier^® ELISA Cp. abortus serum verification kit.

Results

No chlamydial agent was detected by PCR in either the semen samples or in the tissue samples. Additionally, no antibodies against Cp. abortus were detected.

Conclusions

The results suggest that Cp. abortus is very rare, or absent in Swedish bulls and thus the risk for venereal transmission of chlamydial infection through their semen is low. However, because Chlamydophila spp. infection rates seem to differ throughout the world, it is essential to clarify the relative importance of transmission of the infection through semen on cattle fertility.     

A scavenging double mask to reduce workplace contamination during mask induction of inhalation anesthesia in dogs

Background

Workplace contamination by the use of volatile anesthetic agents should be kept to a minimum if a potential health hazard is to be minimised. Mask induction of animals is a common procedure. The present study investigates the efficiency of a novel scavenging double mask in reducing waste gas concentrations in the breathing zone of the anesthetist performing this procedure.

Methods

Twelve beagle dogs (ASA I) undergoing general anesthesia for a dental procedure were intravenously premedicated with medetomidine and butorphanol (10 μg/kg and 0.2 mg/kg). Anesthesia was induced via a custom-made scavenging mask using isoflurane in oxygen. In six dogs (group S), scavenging from the mask was performed whereas in six other dogs (group NS) the scavenging function was disabled. Isoflurane concentration was continuously measured with photoacoustic spectroscopy at the level of the shoulder of the anesthetist before and during mask induction and additionally during intubation. Statistical analysis was performed with a Student t- test and a Mann-Whitney U test (p < 0.05 for significance).

Results

The mean isoflurane concentration during baseline (premedication) was 1.8 ± 0.8 ppm and 2.3 ± 0.6 ppm in group S and NS respectively. This increased during mask induction to 2.0 ± 0.8 ppm and 11.2 ± 6.0 ppm respectively (p < 0.01). The maximum isoflurane concentration ranged from 0.7 ppm to 2.8 ppm and from from 8.3 ppm to 43.7 ppm in group S and NS respectively.

Conclusion

This double mask can be used to induce inhalation anesthesia in dogs. Scavenging from the mask significantly decreases the amount of waste anaesthetic gas concentrations in the breathing zone of the anesthetist. Therefore, such a system can be recommended whenever induction or maintenance of general anesthesia by mask is considered.     

Enantiospecific ketoprofen concentrations in plasma after oral and intramuscular administration in growing pigs

Background

Ketoprofen is a non-steroidal anti-inflammatory drug which has been widely used for domestic animals. Orally administered racemic ketoprofen has been reported to be absorbed well in pigs, and bioavailability was almost complete. The objectives of this study were to analyze R- and S-ketoprofen concentrations in plasma after oral (PO) and intra muscular (IM) routes of administration, and to assess the relative bioavailability of racemic ketoprofen for both enantiomers between those routes of administration in growing pigs.

Methods

Eleven pigs received racemic ketoprofen at dose rates of 4 mg/kg PO and 3 mg/kg IM in a randomized, crossover design with a 6-day washout period. Enantiomers were separated on a chiral column and their concentrations were determined by liquid chromatography-tandem mass spectrometry. Pharmacokinetic parameters were calculated and relative bioavailability (F_rel) was determined for S and R –ketoprofen.

Results

S-ketoprofen was the predominant enantiomer in pig plasma after administration of the racemic mixture via both routes. The mean (± SD) maximum S-ketoprofen concentration in plasma (7.42 mg/L ± 2.35 in PO and 7.32 mg/L ± 0.75 in IM) was more than twice as high as that of R-ketoprofen (2.55 mg/L ± 0.99 in PO and 3.23 mg/L ± 0.70 in IM), and the terminal half-life was three times longer for S-ketoprofen (3.40 h ± 0.91 in PO and 2.89 h ± 0.85 in IM) than R-ketoprofen (1.1 h ± 0.90 in PO and 0.75 h ± 0.48 in IM). The mean (± SD) relative bioavailability (PO compared to IM) was 83 ± 20% and 63 ± 23% for S-ketoprofen and R-ketoprofen, respectively.

Conclusions

Although some minor differences were detected in the ketoprofen enantiomer concentrations in plasma after PO and IM administration, they are probably not relevant in clinical use. Thus, the pharmacological effects of racemic ketoprofen should be comparable after intramuscular and oral routes of administration in growing pigs.