In situ provision of drinking water to grazing dairy cows improves milk production

AIMS: To determine the effect of providing water within the area grazed by dairy cows on milk yield and quality, compared to requiring cows to walk to a distant water trough, on a dairy farm in the Pampa region of Argentina during summer.

METHODS: Holstein dairy cows were allocated to two herds with similar parity, days in milk and milk production. They were grazed in one paddock that was divided in two, with a fixed water trough at one end. Cows were moved twice daily to grazing plots within the paddock. Control cows (n=66) could only access water from the fixed trough, whereas supplemented cows (n=67) also received water from a mobile trough within the grazing plot. Milk production of each cow, and water consumption of the two herds were measured daily over 62 days. Milk composition for each herd was determined weekly from Days 18 to 60 of the study, and grazing behaviour was observed between 08:00 and 16:00 hours on Days 11–15, 19–22 and 39–43.

RESULTS: Over the 62 days of the study, supplemented cows produced 1.39 (SE 0.11) L/cow/day more milk than Control cows (p=0.027). Estimated mean daily water intake was 50.4 (SE 2.1) L/cow/day for supplemented cows and 58.2 (SE 2.7) L/cow/day for Control cows (p=0.004). Percentage total solids in milk was higher for supplemented (12.5 (SE 0.06)%) than Control (12.4 (SE 0.04)%) cows (p=0.047). During the periods of behavioural observation, a higher percentage of cows in the water supplemented than the Control herd were observed in the grazing area (p=0.012).

CONCLUSIONS AND CLINICAL RELEVANCE: This preliminary study demonstrated that provision of water to dairy cows within the grazing plot was beneficial for milk production and composition, and may be associated with longer periods spent within the grazing area, during hot weather in the Pampa region of Argentina.     

Spermatic and oxidative profile of domestic cat (Felis catus) epididymal sperm subjected to different cooling times (24, 48 and 72 hours)

Cooling stored epididymal samples for several days allows facilities to transport and process genetic material post‐mortem. Improvements to this practice allow the preservation of sperm from domestic cats, which are the ideal study model for wild felids. However, the modifications in spermatic features and the oxidative profile are not fully understood in cats. This information is necessary for the development of biotechniques, such as new extenders for cryopreservation. Therefore, the purpose of this study was to evaluate the spermatic and oxidative profile in samples from the epididymal cauda of domestic cats cooled at 5°C for 24, 48 and 72 hr. Spermatozoa were collected from the epididymis cauda. Evaluations consisted of computer‐assisted sperm analysis (CASA), plasma membrane integrity (eosin/nigrosin), acrosome integrity (fast green/rose bengal), sperm morphology, sperm DNA integrity (toluidine blue), mitochondrial activity (3′3 diaminobenzidine), activity of the antioxidant enzymes glutathione peroxidase (GPx) and superoxide dismutase (SOD), measurement of lipid peroxidation (TBARS) and protein oxidation. A decrease in sperm motility parameters was observed after 72 hr of cooling (i.e. total and progressive) with a higher percentage of minor (37.7 ± 6.3%) and total defects (53.4 ± 6.3%). Additionally, a decrease in high mitochondrial activity (Class I: 16.6 ± 2.2%) occurred after 72 hr. The decrease in motility rates after a long cooling time probably was caused by the increase in sperm abnormalities. A long cooling time causes cold shock and mitochondrial exhaustion, but there was no observed change with the oxidative stress condition. Therefore, cat epididymal sperm stored at 5°C appear to maintain a high quality for up to 48 hr of cooling time.     

Pregnancy‐Induced ISG‐15 and MX‐1 Gene Expression is Detected in the Liver of Holstein–Friesian Heifers During Late Peri‐Implantation Period

The bovine embryonic signal interferon‐τ (IFN‐τ) produced by the trophoblast is known to pass through the uterine fluid towards the endometrium and further into the maternal blood, where IFN‐τ induces specific expression of interferon‐stimulated gene expression (ISG), for example in peripheral leucocytes. In sheep, it was shown experimentally by administration of IFN‐τ that ISG is also detectable in the liver. The objective was to test whether ISG can be detected in liver biopsy specimens from Holstein–Friesian heifers during early pregnancy. Liver biopsies were taken on day 18 from pregnant and non‐pregnant heifers (n = 19), and the interferon‐stimulated protein 15 kDa (ISG‐15) and myxovirus‐resistance protein‐1 (MX‐1) gene expression was detected. The expression of both MX‐1 (p: 24.33 ± 7.40 vs np: 9.00 ± 4.02) and ISG‐15 (p: 43.73 ± 23.22 vs 7.83 ± 3.63) was higher in pregnant compared to non‐pregnant heifers (p < 0.05). In conclusion, pregnancy induced ISG‐15 and MX‐1 gene expression in the liver already at day 18 in cattle.     

A rapid and strong laparoscopic-assisted gastropexy in dogs

OBJECTIVE: To develop a technique for laparoscopic gastropexy in dogs and evaluate effects on stomach position and strength of the adhesion between the stomach and abdominal wall. ANIMALS: 8 healthy dogs. PROCEDURE: Dogs were anesthetized, and the abdomen was insufflated with carbon dioxide. A laparoscope was placed through a cannula inserted on the abdominal midline caudal to the umbilicus. Babcock forceps placed through a cannula inserted lateral to the right margin of the rectus abdominus muscle were used to exteriorize the pyloric antrum, a longitudinal incision was made through the serosa and muscular layer of the pyloric antrum, and the seromuscular layer of the pyloric antrum was sutured to the transversus abdominus muscle. After surgery, positive-contrast gastrography was used to evaluate stomach position and the onset of gastric emptying, and ultrasonography was used to assess stomach wall activity and mobility. Dogs were euthanatized 1 month after surgery, and tensile strength of the adhesion was tested. RESULTS: In all dogs, stomach position and the onset of gastric emptying were normal 25 days after surgery, and the pyloric antrum was firmly attached to the abdominal wall 30 days after surgery. Mean +/- SD ultimate load of the adhesion in tension was 106.5 +/- 45.6 N. CONCLUSIONS AND CLINICAL RELEVANCE: The laparoscopic gastropexy technique described in the present study could be performed quickly and easily by an experienced surgeon, resulted in a strong fibrous adhesion between the stomach and abdominal wall, and appeared to cause minimal stress to the dogs.     

Surgical treatment of epulides in dogs: 25 cases (1974-1984)

Epulides were diagnosed and surgically removed in 25 dogs. Histologic examination of the epulides indicated that 40% (10/25) were acanthomatous, 32% (8/25) were ossifying, and 28% (7/25) were fibromatous. Recurrence of the tumor directly resulted in the death of 2 dogs. One of these dogs died of malnutrition 13 months after removal of an ossifying epulis, and regrowth of an acanthomatous epulis that was not resected completely resulted in malnutrition and death in another dog 6 months after surgery. Malignant transformation was observed in a third dog 6 months after removal of an ossifying epulis when an osteosarcoma developed where the epulis had been removed. The range of survival was 6 to 134 months, mean survival time was 43.1 months, median survival time was 49 months, and 1-year survival rate was 92%. Satisfactory long-term tumor control was achieved by aggressive surgical treatment of epulides.     

Free chondral fragment involving the lateral trochlear ridge of the talus in a dog

A saucer-shaped defect involving the lateral trochlear ridge of the talus and a radiopaque joint fragment were evident on radiographs of the left tarsus in a 6-month-old Rottweiler. Surgical treatment involved removal of the joint fragment and debridement of the defect. Histologic interpretation of the specimen was a chondral fragment. It is important to realize the possibility of a lesion in the location described, as this may be an additional site for osteochondrosis dissecans of the canine tarsus.     

Serum prolactin and growth hormone responses to naloxone and intracerebral ventricle morphine administration in heifers

These studies examined responses of serum prolactin (PRL) and growth hormone (GH) to opioid agonist and antagonist administration in heifers. To minimize nonspecific and behavioral effects and to facilitate future studies with specific opioid receptor agonists, a cannula was placed within the third cerebral ventricle of the brain of 4- to 10-mo-old heifers to directly access hypothalamic regions involved in the regulation of PRL and GH secretion. Increasing doses of morphine (M) from 2 to 1,500 micrograms injected into the third cerebral ventricle increased (P less than .001) serum PRL concentrations in a dose-related manner. Growth hormone responses were variable, resulting in elevated (P less than .05) serum concentrations following morphine, but no dose-related effects were apparent. Both PRL and GH responses to 700 micrograms M were absent when an intracerebral ventricle injection of an equimolar dose of naloxone, an opioid receptor antagonist, was administered prior to M. In a replicated 4 x 4 latin square, the effects of intravenous naloxone on PRL and GH responses was tested in young (86 +/- 11 d) and older (234 +/- 6 d) heifers. Naloxone at doses of 1, 2 and 4 mg/kg reduced (P less than .05) serum concentrations of PRL for 45 to 60 min. Mean concentrations of GH tended to be higher (P less than .07) in older heifers All doses of naloxone decreased (P less than .05) serum GH concentrations in older heifers but proved ineffective in younger heifers. There were no differences between doses of naloxone on either PRL or GH. These data suggest that endogenous opioids are involved in the regulation of PRL and GH secretion in heifers.     

The pathogenesis of Pasteurella multocida serotype A:3,4 infection in turkeys: a comparison of two vaccine strains and a field isolate

The pathogenesis of avian pasteurellosis caused by two vaccine strains, M-9 and Clemson University (CU), and a highly virulent field isolate, 86-1913, of Pasteurella multocida (serotype A:3,4) was studied in 7-week-old turkeys inoculated by an oculo-nasal-oral technique. Turkeys inoculated with strain CU and isolate 86-1913 developed severe progressive bacteremia that began at 4 hours postinoculation (PI) and peaked at 16-20 hours PI. Turkeys inoculated with strain CU and isolate 86-1913 had significantly higher concentrations of bacteria in blood and tissues, and greater histologic lesion scores for necrosis, heterophil infiltrates, and intralesional bacteria than turkeys inoculated with strain M-9. Immunohistochemical staining specific for P. multocida demonstrated numerous extracellular bacteria in tissues from turkeys inoculated with strain CU and isolate 86-1913. The mortality for turkeys inoculated with isolate 86-1913 was significantly higher than for turkeys receiving the two vaccine strains.