AAHA senior care guidelines for dogs and cats

This paper provides a working framework for enhancing the well-being of senior pet dogs and cats. Approaches to screening the medical status of senior pets are described in detail, with particular emphasis on establishing baseline data in healthy animals, the testing of clinically ill animals, and assessing senior pets prior to anesthesia and surgery. The management of pain and distress and the application of hospice and palliative care are addressed. Advice on ways to approach euthanasia and dealing with end-of-life issues is also provided.     

Preslaughter handling effects on pork quality and glycolytic potential in two muscles differing in fiber type composition

The objective of the present experiment was to investigate the effects of transportation, lairage, and preslaughter stressor treatment on glycolytic potential and pork quality of the glycolytic longissimus and the oxidative supraspinatus (SSP) or serratus ventralis (SV) muscles. In a 2 x 2 x 2 factorial design, 384 pigs were assigned randomly either to short (50 min) and smooth or long (3 h) and rough transport, long (3 h) or short (< 45 min) lairage, and minimal or high preslaughter stress. Muscle samples were taken from the LM at 135 min and from the SSP at 160 min postmortem for determination of the glycolytic potential and rate of glycolysis. At 23 h postmortem, pork quality was assessed in the LM and the SV. Effects of transport and lairage conditions were similar in both muscle types. Long transport increased (P < 0.01) the glycolytic potential and muscle lactate concentrations compared with short transport. Both long transportation and short lairage decreased (P < 0.01) redness (a* values) and yellowness (b* values) of the LM and SV. In combination with short lairage, long transport decreased (P < 0.05) pork lightness (lower L* values), and electrical conductivity was increased (P < 0.05) after long transport. Several interactions between stress level and muscle type (P < 0.001) were observed. High preslaughter stress decreased (P < 0.001) muscle glycogen in both the LM and SSP, but this decrease was greater in the LM. Lactate concentrations were increased (P < 0.001) only in the LM by high preslaughter stress. Increases in ultimate pH (P < 0.001) and decreases in a* values (P < 0.01) were greatest in the SV, whereas increases in electrical conductivity (P < 0.001) were greatest in the LM. The lack of interactions among transportation, lairage, and muscle type was attributed to the relatively minor differences in stress among treatments. It was concluded that, in glycolytic muscle types such as the LM, the high physical and psychological stress levels associated with stress in the immediate preslaughter period have a greater effect on the water-holding capacity of the meat and may promote PSE development. Conversely, oxidative muscle types tend to have higher ultimate pH values and produce DFD pork in response to intense physical activity and/or high psychological stress levels preslaughter.     

Effects of chromium propionate on growth, carcass traits, and pork quality of growing-finishing pigs

An experiment was conducted to determine the effect of dietary Cr propionate (CrProp) on growth, carcass traits, and pork quality of crossbred finishing gilts. Dietary treatments were 0 or 200 ppb Cr (as CrProp; as-fed basis), and each treatment was replicated four times with five gilts per replicate pen. Gilts were fed diets containing 0.82% lysine from 73 to 80 kg BW and 0.64% lysine from 80 to 115 kg BW. At the end of the trial, carcass and pork quality data were collected from four gilts per replicate. Average daily gain, ADFI, and G:F were not affected (P = 0.76 to 0.96) by CrProp. Before delivery at the abattoir, shrink loss was determined after an 18-h fast (fasting shrink) and after hauling (shipping shrink) pigs for 2.66 h (209.2 km). Fasting, shipping, and overall shrink were not affected (P = 0.14 to 0.39) by CrProp. Carcass length was increased (P = 0.03) in pigs fed CrProp. Loin muscle area, 10th-rib backfat thickness, average backfat thickness, dressing percent, muscle score, fat-free lean, and percent lean were not affected (P = 0.18 to 0.95) by CrProp. Twenty-four-hour loin pH was increased (P = 0.10) in pigs fed CrProp, but 45-min loin and ham pH and 24-h ham pH were not affected (P = 0.39 to 0.83) by CrProp. Subjective (color, marbling, firmness, and wetness) and objective (Commission Internationale de l'Eclairage L*, a*, b*) assessments of the loin muscle (at the 10th-rib interface) were not affected (P = 0.62 to 0.99) by CrProp. Forty-eight-hour drip (P = 0.10) and 21-d purge loss (P = 0.01) were decreased in pigs fed CrProp, but cook and total loss (drip + cook loss) and shear force were not affected (P = 0.35 to 0.53) by CrProp. Plasma cortisol, glucose, and lactate concentrations were not affected (P = 0.28 to 0.97) by CrProp after transportation or during exsanguination. These data indicate that CrProp may improve some aspects of pork quality (loin pH, drip and purge loss) but not growth performance or carcass traits.     

Fat-Tailed Sheep Traits as Affected by Docking

The literature mostly indicates that docking fat-tailed lambs initially reduces growth but that post-weaning growth and feed conversion efficiency then increase. The amount of fat deposited, the total separable lean meat to fat ratio and the meat quality all increase, while the percentage of bone in the carcase either decreases or does not change in the carcases of the docked lambs. Wool growth and characteristics are, in general, not affected and reproductive traits in ewes and lambs are improved by docking. The rectal temperature, respiration rate and pulse rate are decreased following docking. The concentrations of immunoreactive beta-endorphin and cortisol in the plasma and the incidence of foot stamping and restlessness, as indicators of stress, increase after docking. Other constituents of the blood are not significantly altered following docking or by the methods of docking. Docking of fat-tailed sheep using rubber rings at one day of age can be recommended. This revised version was published online in July 2006 with corrections to the Cover Date.     

Evaluation of PCR to detect Theileria parva in field-collected tick and bovine samples in Tanzania

The ability of PCR to detect infections of Theileria parva, the cause of East Coast Fever, in field-collected tick and bovine samples from Tanzania was evaluated. PCR-detected infection prevalence was high (15/20, 75%) in unfed adult Rhipicephalus appendiculatus ticks that fed as nymphs on an acutely-infected calf, but low (22/836, 2.6%) in unfed adult R. appendiculatus collected from field sites in Tanzania. Tick infection prevalence was comparable to that in previous studies that used salivary gland staining to detect T. parva infection in field-collected host-seeking ticks. Of 282 naturally-exposed zebu calves, seven had PCR-positive buffy coat samples prior to detection of Theileria spp. parasites in stained buffy coat cells or lymph node biopsies. Evidence of Theileria spp. infections was detected in stained smears of lymph node biopsies from 109 calves (38.6%) and buffy coat samples from 81 (28.7%), while buffy coat samples from 66 (23.4%) were PCR-positive for T. parva. Implications of these findings for the sensitivity and specificity of the PCR are discussed.     

Familial non-rcd1 generalised retinal degeneration in Irish setters

Four Irish setters were diagnosed with bilateral retinal degeneration and cataracts at an age ranging from six to 11 years. In three of these dogs, progressive night blindness was reported from an age of eight to 11 years. In the fourth dog, aged six, no signs of visual impairment had been noticed. In all four dogs, the rod-cone dysplasia type 1 (rcd1) mutation was excluded as a cause, using an allele-specific PCR. From their three-generation pedigrees, a familial relationship was detected in three out of four dogs, which were also related to four additional Irish setter dogs with a history and clinical signs suggestive of late-onset progressive retinal degeneration. These results suggest the existence of a possibly hereditary, late-onset, progressive retinal atrophy in the Irish setter breed, that is distinct from rcd1.     

Effects of feeding ergovaline on lamb performance in a heat stress environment

Lambs exposed to a heat-stressed environment (33 degrees C, 50% relative humidity) were used in three experiments to determine whether ergovaline (EV) is the primary toxin involved in fescue toxicosis. The first study evaluated the effects of feeding diets containing increasing levels of endophyte-infected tall fescue seed (E+) and decreasing levels of endophyte-free tall fescue seed (E-). The second and third study evaluated the response to a diet that contained synthetic EV added to an E- diet and the response to a diet containing endophyte-infected ryegrass seed (R+) with an elevated concentration of EV. In Exp. 1, lambs were fed diets of: 1) 10% E- and 0% E+, 2) 5% E- and 5% E+, or 3) 0% E- and 10% E+. Increasing the percentage of E+ in the diet resulted in a linear decrease (P < 0.01) in feed intake (as-fed basis), skin temperature, thermocirculation index (TCI), and serum prolactin. Body weight gain also decreased (P < 0.06). Respiratory rate and core body temperature were not affected by the 5 or 10% E+ diets. In Exp. 2, lambs were fed diets that contained: 1) 10% E-, 2) 10% E- with synthetic EV added at a level equivalent to the 10% E+ diet, or 3) 10% E+. Feed intake (as-fed basis), body weight gain, and skin temperature did not differ for lambs fed the E- and EV diets. The EV diet elicited a decrease (P < 0.05) in TCI and prolactin compared with the E- diet. The TCI for lambs fed EV did not differ (P > 0.10) from the E+ lambs; however, serum prolactin was lower (P < 0.05) for lambs on the E+ diet than for those fed EV. Core body temperature was not affected (P > 0.10) by feeding EV or E+ fescue seed in Exp. 2. In Exp. 3, lambs were fed diets that contained: 1) 10% E-, 2) 3.24% R+ and 6.76% E-, which added an equivalent amount of EV to E+ diets but reduced concentrations of other ergot alkaloids, or 3) 10% E+. Lambs fed the E+ diet and maintained at 33 degrees C had lowered feed intake (as-fed basis), skin temperature, and TCI compared with lambs fed the E- or R+ diets (P < 0.05). Lambs fed the E+ diet had increased rectal temperatures and lowered serum prolactin compared with lambs on the R+ diet (P < 0.05). Lambs on the R+ diet had a greater rectal temperature and lower serum prolactin than lambs on the E- diet (P < 0.05). These results suggest that EV is a fescue toxin; however, other alkaloids might work synergistically with EV, causing the full expression of fescue toxicosis.