Can testicular artery Doppler velocimetry values change according to the measured region in dogs?

Testicular tissue maintenance is performed by the testicular artery, and the hemodynamics of this artery can be evaluated using Doppler ultrasonography. The aim of this study was to characterize the peak systolic velocity (PSV), end diastolic velocity (EDV), pulsatility index (PI) and resistivity index (RI) of five regions of the testicular artery in dogs, including two proposed regions and three that have been previously described. Twenty‐two dogs were used, and the PSV, EDV, PI and RI of the testicular artery were measured in five regions: proximal, medial and distal supratesticular; marginal; and intratesticular. The median values for PSV (cm/s), EDV (cm/s), PI and RI in the five regions were as follows: proximal supratesticular (23.1, 3.7, 2.1 and 0.8); medial supratesticular (17.2, 4.5, 1.5, and 0.7); distal supratesticular (12.2, 5.7, 0.8, and 0.5); marginal (11.3, 6.5, 0.5, and 0.4); and intratesticular (5.7, 3.5, 0.5, and 0.4). There was a difference between the PSV of the medial and distal supratesticular regions. There were differences in the PSV, EDV, PI and RI among the distal supratesticular, marginal and intratesticular regions. Measurements of PSV, EDV, PI and RI of the testicular artery in dogs at the proposed regions showed different results due to the hemodynamic and morphological differences of the artery during its course in the spermatic cord and to the testicles. It is necessary to identify the region in testicular artery Doppler velocimetric evaluations of dogs, given that there is a difference according to the region measured.     

Colour and pulsed Doppler ultrasonographic study of the canine testis

This study was performed to characterize the normal blood flow of the canine testis and to measure the peak systolic velocity (PSV), end-diastolic velocity (EDV), resistive index (RI) and pulsatility index (PI) of testicular arteries weekly during a period of 6 months in five healthy Beagle dogs and to evaluate whether there were any change along this time. The ultrasonographic exams were made with an 11 MHz linear transducer. The vessels of the testes were subdivided into three categories: supratesticular arteries, marginal artery and intratesticular vessels. At the supratesticular arteries, two measurements were recorded at the cranial and the looping parts. No significant differences in any of the parameters studied were observed for the 6 months that the study was performed. The cranial part of the supratesticular artery showed a flow pattern of high-resistive vessel, whereas in the looping part of the supratesticular artery, marginal and intratesticular arteries, the flow showed a low-resistance pattern. PSV, RI and PI values were higher at the cranial part of the supratesticular artery, followed by the looping part of the supratesticular artery, marginal and intratesticular vessels. EDV measurements were higher in the looping part of the supratesticular artery.     

Effect of a single injection of gonadotropin-releasing hormone (GnRH) and human chorionic gonadotropin (hCG) on testicular blood flow measured by color doppler ultrasonography in male Shiba goats

Although color Doppler ultrasonography has been used to evaluate testicular blood flow in many species, very little has been done in goat. Eight male Shiba goats were exposed to a single intramuscular injection of either gonadotropin-releasing hormone (GnRH group; 1 µg/kg BW) or human chorionic gonadotropin (hCG group; 25 IU/kg BW). Plasma testosterone (T), estradiol (E2) and inhibin (INH) were measured just before (0 hr) and at different intervals post injection by radioimmunoassay. Testis volume (TV) and Doppler indices, such as resistive index (RI) and pulsatility index (PI) of the supratesticular artery, were measured by B-mode and color Doppler ultrasonography, respectively. The results indicated an increase in testicular blood flow in both groups, as RI and PI decreased significantly (P<0.05), but this increase was significant higher and earlier in hCG group (1 hr) than in the GnRH group (2 hr). A high correlation was found for RI and PI with both T (RI, r= −0.862; PI, r= −0.707) and INH in the GnRH group (RI, r=0.661; PI, r=0.701). However, a significant (P<0.05) correlation was found between E2 and both RI (r= −0.610) and PI (r= −0.763) in hCG group. In addition, TV significantly increased and was highly correlated with RI in both groups (GnRH, r= −0.718; hCG, r= −0.779). In conclusion, hCG and GnRH may improve testicular blood flow and TV in Shiba goats.     

Doppler velocimetric parameters of the testicular artery in healthy dogs

This study aimed to examine the Doppler velocimetric pattern of the testicular artery of small dogs in two different locations. Testes of 21 dogs were evaluated by two-dimensional ultrasonography to measure testicular volume and by Doppler ultrasonography to record the velocimetric patterns of the testicular artery in the spermatic cord and marginal location. The volume of left testes (4.70 ± 1.22 cm³) was significantly higher than the volume of the right testes (4.45 ± 1.17 cm³). Peak systolic velocity (PSV) of the left spermatic cord was significantly higher than the right side. End-diastolic velocity was significantly higher in the marginal artery than the spermatic cord on both sides; however, resistance and pulsatility indexes were significantly lower in the marginal artery. Results demonstrate the viability of Doppler ultrasonography for characterization of the testicular artery in small dogs and Doppler velocimetric values vary according to the location of measurement along the artery.     

Colour Doppler ultrasound imaging of blood flows variations in neoplastic and non‐neoplastic testicular lesions in dogs

Testicular tumours are the most common neoplasms in male dogs accounting for approximately 90% of all tumours affecting the genitourinary tract. Gray‐scale ultrasonography in combination with colour and power Doppler imaging has been well accepted as an accurate technique for assessing scrotal lesions and vascularization of the testis. Colour Doppler sensitivity for low blood flows appears promising in the study of testicular disorders. The aim of this study was to assess if colour and power Doppler ultrasound is a good tool for the investigation of testicular lesions in dogs, to report the sonographic features of lesions and to measure colour and power Doppler parameters such as resistive index (RI), pulsatility index (PI), hypovascularization and hypervascularization (VI) determining if they can be used to distinguish testicular neoplasms from the wide spectrum of non‐neoplastic pathological findings. In this study, 50 male dogs of various breeds, aged between 7 and 14 years, presented with testicular disorders were selected. RI and PI were calculated. Mean RI values for neoplastic, inflammatory and degenerative lesions were 0.54, 0.45 and 0.58, respectively. Mean PI values were 0.62, 0.55 and 0.63, respectively. Hypovascularization and hypervascularization of the lesion were evaluated throughout the vascularity index (VI). Vascular signals in neoplasms were significantly intensified around and inside the mass if compared with those measured during inflammatory and degenerative lesions. VI markedly increased in solid tumours. Pathological testes were removed; macroscopical, histological and immunoistochemical evaluations were carried out. Colour Doppler showed increased intralesional and peripheral flows in all neoplastic lesions analysed. No flows were detected around cysts.     

Ultrasonographic measurement of normal renal parameters

Both kidneys were imaged ultrasono-graphically in each of 100 normal adult dogs. Small but significant differences were found in the dimensions of the left and right kidneys and in renal dimensions of male and female dogs of similar bodyweight. There was a statistically significant correlation between renal length and bodyweight (r = 0–84, P<0–001). The relationship between renal length and bodyweight was linear except at very low or very high bodyweights. There was also a statistically significant correlation between renal volume and bodyweight (r = 0–91, P<0–001), and the relationship remained linear even at extremes of bodyweight. Graphs could therefore be constructed for renal lengthy bodyweight and renal volume/bodyweight with 95 per cent confidence limits.     

Poor semen quality in Irish wolfhounds: A clinical, hormonal and spermatological study

On the basis of clinical observations, Irish wolfhounds were suspected as being subject to a relatively high incidence of soft testicular consistency and low semen quality. Thirty-seven Irish wolfhounds and 67 dogs of other breeds (control group) were therefore examined. Conventional andrological studies were performed in both groups, these included libido testing, palpation and measurement of testes and semen evaluation. Semen evaluation was performed both manually and by videomicrographic analysis. Testosterone concentrations were measured both before and after human chorionic gonadotropin challenge in the Irish wolfhounds. The Irish wolfhounds had lower libidos than the control group. More Irish wolfhounds (21-2 per cent) exhibited low semen quality than the control group (6-1 per cent). Soft testicular consistency occurred more frequently in Irish wolfhounds (25-7 per cent) than in the control group (10-5 per cent). In the control group, bodyweight correlated significantly with total sperm count. Serum testosterone concentration did not correlate with semen quality parameters.     

Salmon oil supplementation in dogs affects the blood flow of testicular arteries

The administration of fish oils is known to cause changes in several reproductive parameters of domestic animals. The ingestion of polyunsaturated fatty acids (PUFAs) of the omega-3 family, such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), has been described and correlated with changes in the semen quality, testosterone levels and male fertility. Nevertheless, few studies monitored and registered effects after ceasing supplementation. In the present study, we monitored the Doppler velocimetric and ultrasonographic parameters of nine dogs' testis for 90 days (D90) checking the effect of salmon oil supplementation, and monitoring continued for 60 days more, after ceasing supplementation (D150). Ultrasonographic evaluations comprised determining the Doppler velocimetric parameters, testicular and epididymal volume, and testicular echotexture. Peak systolic velocity (PSV) as well as final diastolic velocity (EDV) in the supratesticular arteries (STA), and marginal artery (MA) increased during the period of treatment and kept that level up to D150. There was no difference between the fish-oil supplementation period and the unsupplemented one regarding the testicular and epididymal volume and echogenicity and heterogeneity characteristics. A negative correlation was found between heterogeneity of testis and sperm production (r = −.41, p = .008). Doppler velocimetry indices were affected by the supplementation, leading to an increase in testicular blood flow.     

Examination of jackass (Equus asinus) accessory sex glands by B-mode ultrasound and of testicular artery blood flow by colour pulsed-wave Doppler ultrasound: Correlations with semen production

The accessory sex glands play a major role in the production of seminal plasma, and testicular artery blood flow seems to strongly influence testicular function. However, very little ultrasound imaging of these organs has been undertaken in donkeys. The present work reports the results of such examinations in five jackasses along the year. The accessory glands were inspected by B-mode ultrasound while the testicular artery blood flow was assessed by colour pulsed-wave Doppler ultrasound. The testicular artery was examined at pampiniform plexus (PPT), supratesticular area (ST) and capsular artery (CA). Values were recorded for the total arterial blood flow (TABF), peak systolic velocity (PSV), end-diastolic velocity (EDV), resistive index (RI), pulsatility index (PI) and time average maximum velocity (TAMV). Semen was obtained and assessed for sperm concentration, viability, abnormalities and motility using a CASA system. The bulbourethral glands, prostate and ductus deferens ampullae were relatively larger than in the stallion. Bulbourethral glands and ampullae sizes were inversely correlated with sperm motility. An reduction in blood flow between the level the PPP and the CA was observed, helping to reduce testis temperature and oxygen pressure. Blood flow at the CA showed the strongest correlation with semen production. PI and RI were positively correlated with the CASA motility variable STR (p = .02, p = .06) and sperm viability (p = .01), while sperm concentration (p = .05) correlated inversely with PSV, EDV, TAMV and TABF. EDV also correlated negatively with the CASA variables VSL, LIN, STR and VAP (p ≤ .05). PI and RI were also negatively correlated with testis length (p = .0093, p = −.0438).     

DOPPLER MEASUREMENT OF SPLANCHNIC BLOOD FLOW DURING DIGESTION IN UNSEDATED NORMAL DOGS

The purpose of this study was to measure splanchnic blood flow during digestion in unsedated dogs by using duplex Doppler sonography. The study population consisted of 12 healthy dogs. Blood flow in the cranial mesenteric artery, the celiac artery, and the aorta was measured before a test meal and at 20, 60, and 90 minutes after eating. The following measurements were made or calculated: vessel diameter, peak systolic velocity, end diastolic velocity, mean velocity, resistive index, pulsatility index, and flow volume. There was a significant postprandial decrease in the resistive and pulsatility indices in both the cranial mesenteric (preprandial RI = 0.867, postprandial RI = 0.796, preprandial PI = 3.033, postprandial PI = 2.173) and the celiac (preprandial RI = 0.854, postprandial RI = 0.769, preprandial PI = 2.639, postprandial PI = 1.930) arteries. In both vessels the end diastolic velocity, the mean velocity, and the flow volume increased significantly postprandially. These changes occurred significantly earlier in the celiac artery than in the cranial mesenteric artery. The findings most likely correspond to postprandial splanchnic vasodilation. Doppler ultrasound provide a good methode of detecting changes in postprandial splanchnic blood flow in the dog.     

Melatonin improves testicular haemodynamics,echotexture and testosterone production in Ossimi rams during the breeding season

The objective was to determine effects of a single parenteral dose of melatonin on testicular blood flow indices, testicular echogenicity and plasma testosterone concentrations in rams during the physiological breeding season. We hypothesized that melatonin enhances testicular blood flow, echogenicity and plasma testosterone concentrations during the breeding season in rams. During the breeding season, 12 sexually mature Ossimi rams were randomly allocated to either a melatonin group (n = 8) that received 18 mg of melatonin in 1 ml of corn oil (injected SC) or a control group (n = 4) that received 1 ml corn oil only. Blood collection and ultrasonographic assessment of the testes and supratesticular arteries were conducted immediately before treatment (W0) and once weekly for 6 weeks after melatonin injection (W1-W6). Mean plasma testosterone concentrations were greater (p < .05; at least 1 ng/ml) in the melatonin-treated group compared to the control group from W4 to W6 after treatment. A decrease (p < .05) in both resistive index (RI) and pulsatility index (PI) began 1 week after melatonin injection (W1) and persisted until the end of the experiment, with mean RI and PI values in the melatonin group lower (p < .05) than those in the control group on W3 and W4. Furthermore, plasma testosterone concentrations in melatonin-treated rams were inversely correlated to both RI and PI (r = −.7 and −.6, respectively, p < .01). Testicular echogenicity decreased (p < .05) 1 week after melatonin injection (W1) and remained lower (p < .05) in the melatonin-treated group compared to the control group until the end of the study (W6). In conclusion, melatonin administration significantly altered testicular blood flow and echogenicity and increased plasma testosterone concentrations in Ossimi rams during the breeding season.     

Scrotal width as an index of testicular size in dogs and its relationship to body size

Measurements of scrotal width were strongly correlated with testicular weight in 71 dogs (r = 0–919) and thus provided a convenient index of testicular size and potential sperm production. However, to be useful in trying to predict male fertility this measurement had to be adjusted for bodyweight. A graph is presented which allows estimation of ‘average’ scrotal width and its 95 per cent confidence limits for potentially fertile dogs of bodyweight between 5 and 50 kg. With one exception, dogs with scrotal widths below the 95 per cent confidence limits had very few or no spermatozoa in smears from the cauda epididymidis.     

Results of extra-articular stabilisation following open reduction of coxofemoral luxation in dogs and cats

This report describes 14 dogs (mean age six years, mean bodyweight 25 kg) and three cats (mean age 9-3 years, mean bodyweight 6–7 kg) with coxofemoral luxations of one to 91 days duration (median four days). In 47 per cent of the cases concomitant fractures or luxations (including three bilateral luxations) were present. Closed reduction was immediately unsuccessful in five cases and eventually unsuccessful in seven cases, whereas in five cases the nature of the additional trauma required surgical intervention. Via a craniolateral approach to the hip joint, combined with trochanter osteotomy in 24 per cent of the cases, the luxation was reduced and remnants of the capsule were sutured in 82 per cent of the cases. In all cases an extra-articular iliofemoral suture band was applied to limit the range of motion of the femoral head. The technique is described and illustrated in detail. The success rate proved to be strongly related to the suture material and varied from excellent to poor. This extra-articular stabilisation technique had excellent results in acute and chronic coxofemoral luxations in dogs when multifilamentous non-absorbable material was used, even when no additional non-weightbearing sling was used.     

Importance of water for the health and productivity of the dairy cow

Four lactating Friesian cows (average weight 485 kg, milk yield 22 kg d-1) were maintained in completely controlled circumstances and deprived of water for 72 hours. During this period they were carefully monitored and lost 100 kg in bodyweight, principally accounted for by cumulative losses of water in milk, urine, faeces and respired air. The mean rates of respiration and rumen contraction decreased by approximately 50 per cent. Mean body temperature increased by 0.5 degrees C, but pulse rate did not change significantly. Dry matter intake, particularly of hay, decreased rapidly to less than 10 per cent of normal on the third day. Milk yield decreased only slightly during the first 24 hours but on the third day the average yield was only 28 per cent of normal; the composition of the milk did not change significantly. There were significant progressive increases in serum sodium concentration (after four hours water deprivation), osmolality (after 24 hours), urea (after 38 hours), copper (after 48 hours) and magnesium and total protein concentration (after 62 hours); packed cell volume (measured with a Coulter Counter) increased after 38 hours but packed cell volume (determined in a microhaematocrit centrifuge) increased only after 62 hours. In spite of the dehydration the cows showed no signs of distress. Within 48 hours of the cows being given free access to water, bodyweight, appetite, milk yield and blood composition had returned almost completely to normal.     

A morphological study of simple testicular cysts in the ostrich (Struthio camelus)

Simple testicular cysts are rare in mammals and of unknown aetiology, but dietary conditions have been implicated in this phenomenon in poultry. This study characterises the structural features of simple intratesticular cysts in the ostrich. Seven testes from a total of 15 sexually mature ostriches slaughtered during the breeding season were used. The testes contained multifocal, fluid-filled, unilocular cysts which were lined by a simple squamous or low cuboidal epithelium and surrounded by a thick layer of fibrous connective tissue. The cysts developed within seminiferous tubules and displayed morphological features similar to those reported in man and domestic poultry. The testis parenchyma revealed several foci composed of intermingled normal seminiferous tubules and variably sized intratesticular cysts. The atrophic tubules lay within a mass of hyperplastic, fibroblastic intertubular connective tissue in the proximity of large cysts and their formation appeared to result from hydrostatic pressure exerted by cysts. Morphological evidence supports a continuous process of cyst formation in the affected testis and a concomitant progressive loss of atrophic seminiferous tubules. A pathogenetic scenario of cyst formation and the effect of simple cysts on testicular histology has been proposed. Although the course of this phenomenon remains unknown, its impact on the fertility of this economically important bird deserves closer scrutiny.     

Doppler ultrasonographic changes in the canine kidney during normovolaemic anaemia

The haemodynamics of the canine left renal artery (LRA) and interlobar artery (ILA) were evaluated in eleven fasted, healthy, conscious beagles with severe acute (haematocrit [Hct] 16%), moderate chronic (Hct 26%) and mild chronic (Hct 34%) normovolaemic anaemia using Doppler ultrasound. Heart rate, peak systolic velocity (PSV), end diastolic velocity (EDV), time-averaged mean velocity (TAVmean), pulsatility index (PI) and resistive index (RI) were recorded. Doppler values in the dogs following the induction of anaemia states were compared with corresponding values in the same dogs prior to the induction of anaemia. Left renal artery mean PSV, mean PI and mean RI were significantly higher and the mean EDV was significantly lower in severe acute anaemia. No significant change was seen in mean values of the same parameters in moderate or mild chronic anaemia. There was no significant change in TAVmean of the LRA or mean PI and mean RI of the ILA in any grade of anaemia. Acute, severe normovolaemic anaemia significantly altered LRA Doppler parameters in resting dogs without influencing those of the ILA. Moderate or mild chronic anaemia had no effect on any renal Doppler parameter.     

EFFECTS OF SEDATION WITH MIDAZOLAM AND BUTORPHANOL ON RESISTIVE AND PULSATILITY INDICES IN HEALTHY DOGS

Resistive index (RI) and pulsatility index (PI) are indirect measurements of blood flow resistance that may be measured by pulsed wave Doppler ultrasonography. Chemical restrain may potentially alter the indices although it is required to perform ultrasonography in some patients. The purpose of this study was to describe values for both intrarenal and ocular RI and PI within the same subject in clinically normal dogs sedated with a midazolam and butorphanol combination and evaluate if there are any significant changes between sedated and nonsedated dogs. Fifteen healthy Beagle dogs were studied by Duplex Doppler interrogation in interlobar or arcuate arteries of the kidney and long posterior ciliary artery. Pulse rate and systolic blood pressure were also determined. All measurements were recorded before and after the administration of a sedative combination of midazolam (0.2 mg/kg) and butorphanol (0.2 mg/kg). Mean comparison tests (paired t-tests or Wilcoxon's rank-sum test) were used to determine if any significant differences existed between right and left renal values or right and left ocular values. A correlation study (Pearson or Spearman) was applied between RI, PI, and systolic pressure, and pulse rate. RI and PI were significantly higher in sedated Beagles than in unsedated Beagles. There was neither correlation between index and systolic blood pressure nor pulse rate. In conclusion, provided that normal RI and PI increase in sedated animals, then reference ranges should be higher when sedated--healthy or ill--animals are evaluated.     

DOPPLER ULTRASONOGRAPHIC ESTIMATION OF RENAL AND OCULAR RESISTIVE AND PULSATILITY INDICES IN NORMAL DOGS AND CATS

Resistive index (RI) and pulsatility index (PI) are indirect measurements of blood flow resistance that may be used to evaluate vascular changes in renal and ophthalmologic diseases. To our knowledge, no reports are available describing values for renal and ocular PI index in the unsedated dog and ocular RI and PI indices in the unsedated cat. The purpose of this study was to measure normal values for both intrarenal and ocular RI and PI within the same subject in unsedated clinically normal dogs and cats. Twenty-seven dogs and 10 cats were considered healthy by means of physical examination, CBC, biochemical profile, urinalysis, and ultrasonography. Systolic blood pressure was measured by Doppler ultrasonography. Intrarenal and ocular arteries were scanned by pulsed Doppler ultrasonography to calculate RI and PI. No significant differences were noted between the values obtained for the right vs. the left kidney and eye. The upper values of these indices were calculated as mean+2 standard deviations resulting in 0.72 and 1.52 for dog renal RI and PI; 0.7 and 1.29 for cat renal RI and PI; 0.76 and 1.68 for dog ocular RI and PI; and 0.72 and 1.02 for cat ocular RI and PI.     

Seasonal variation in testicular blood flow dynamics and their relation to systemic and testicular oxidant/antioxidant biomarkers and androgens in rams

The environmental temperature increased during summer and decreased during winter to the limits that might negatively affect animal and human reproduction. The responses of Egyptian rams to either hot or cold climatic conditions were studied in six mature rams subjected to weekly testicular Doppler ultrasonographic examination, blood sampling, seminal plasma collection and semen evaluation. The maximum environmental temperature and the relative humidity were used to classify the climatic condition according to the heat stress equation of sheep into hot months where temperature–humidity index (THI) was >26 (31.67 ± 0.54), and cold months where THI was <22 (18.39 ± 0.41). Testosterone, estradiol, superoxide dismutase (SOD), glutathione peroxidase (GPX) and lipid peroxide product (malondialdehyde, MDA) were measured in both blood and seminal plasma, while catalase (CAT) and reduced glutathione (GSH) were measured in blood and seminal plasma, respectively. Results revealed that, during the hot months, rams displayed significantly decreased testicular blood flow, increased seminal plasma MDA, decreased seminal plasma (SOD, GPx and GSH) and blood CAT antioxidant enzymes. The present study evidenced two novel findings: (a) the marked decrease in testicular blood flow volume, that is remarkable increase in both resistive index (RI) and pulsatility index (PI) values, during hot months could be negatively affected both seminal plasma enzymatic activities and seminal attributes, and (b) the SOD and GPx activities in seminal plasma of such animals were suitable predictive markers for seminal attribute evaluation.     

Castration of piglets: the analgesic effects of intratesticular and intrafunicular lidocaine injection

OBJECTIVE: The aim of this study was to evaluate the analgesic effect of intratesticular and intrafunicular lidocaine for the surgical castration of piglets and to investigate the degree of nociception induced by lidocaine injection. STUDY DESIGN: Prospective controlled experimental study. ANIMALS: Forty-seven male Norwegian landrace piglets with normal testicular anatomy, aged 22 (+/-2.6 SD) days and weighing 7.4 +/- 1.4 kg. MATERIALS AND METHODS: Anaesthesia was induced and maintained using halothane delivered in oxygen. End-tidal halothane was stabilized at 1.3% for 20 minutes before mean arterial blood pressure (MAP) pulse rate and electroencephalography (EEG) monitoring began. After 5 minutes of data collection, scrotal skin was desensitized with lidocaine before either an intrafunicular (IF) (n = 15) or an intratesticular (IT) (n = 16) lidocaine injection was made. Pigs in the control group (n = 16) did not receive lidocaine. Ten minutes later, a scalpel and an emasculator were used to cut the funiculus spermaticus. The MAP, pulse rate and EEG were monitored continuously for 5 minutes after castration. RESULTS: During castration, MAP increased significantly, while pulse rate and EEG theta power fell significantly more in control, compared with the IT or IF groups. EEG alpha power fell more in the control group than in the IF group. No significant differences were found between the IF and IT groups. EEG, MAP and pulse rate responses to castration in the control group were significantly larger than the response to lidocaine injection. CONCLUSION/CLINICAL RELEVANCE: Injecting lidocaine into the funiculus spermaticus or into the testes is effective in reducing signs of nociception caused by castration. Lidocaine injection is less noxious than castration without local anaesthetic.