Ante-mortem detection of PSE and DFD by infrared thermography of pigs before stunning.
Using water-holding capacity and colour measurements (L and b values) as objective quality parameters, we have observed an increasing incidence of meat quality defects with the increasing skin surface temperature of pigs by infrared thermography prior to stunning. Below 32·2°C, 50% of the 32 pigs measured had normal meat while the other half showed meat quality defects. Above 32·2°C, however, 71% of the 49 pigs showed meat quality problems classified as moderate PSE (6%), PSE (30%), moderate DFD (22%) and DFD (37%). At this temperature level, meat quality of the remaining pigs was normal and decreased to 29%. Although infrared thermography of live animals cannot predict whether the meat will be PSE or DFD, it seems to be a practical and rapid method to detect pigs who will yield a significant proportion of meat quality defects. An early post-mortem identification of meat quality could supply the missing information.
Effects of housing conditions of slaughter pigs on some post mortem muscle metabolites and pork quality characteristics.
The results of two experiments studying the effects of housing conditions on post mortem muscle metabolism and meat quality are presented. In the first experiment slaughter pigs (n=71) from two different crossings, were raised at a density of 0.7 m(2)/animal (10 pigs/pen) either with (enriched) or without (conventional) a bedding of daily fresh straw. In the second experiment, animals (n=60) were reared under either conventional or free range housing (1.25 m(2)/animal, 30 pigs per pen) conditions. Main differences between conventional and enriched housed pigs were found in the biceps femoris (BF) muscle, and related to temperature, drip loss and colour. Association studies revealed that there were significant correlations between early (0-4 h) post mortem muscle pH and glycogen and lactate concentrations and between muscle pH measured at 1 h post mortem and muscle rigidity, expressed as the rigor value. There were significant differences with respect to meat quality and post mortem metabolism of the longissimus lumborum (LL), between conventional and free-range pigs. Early post mortem pH (0-4 h) was highest in the free-range pigs, due to low lactate concentrations. The relatively fast pH decline in the conventionally housed group resulted in increased amounts of water exuding from the meat, as measured by the filter paper method. The ultimate pH, was lowest in the free-range animals. The differences in ultimate pH, however, had no effect on drip or cooking losses. It can be concluded from these results that enrichment of the housing system has little effect on the course of the post mortem metabolism and meat quality. However, increasing the freedom of movement by applying lower stocking densities, affects the post mortem muscle metabolism, resulting in reduced water exudation. Correlations up to 0.7 between energetic parameters are not sufficiently high to be useful to predict meat quality of individual carcasses.
Diagnostic and therapeutic studies on chronic diarrhea in dairy animals
The study was conducted to determine the etiology of chronic diarrhea in dairy animals. Seven causes of chronic diarrhea were established in dairy cattle and buffaloes. Balantidiasis in 37.6 per cent, dietary diarrhea in 9.9 per cent, chronic salmonellosis in 6.9 per cent cases of chronic diarrhea, secondary copper deficiency and amphistomiasis in 6.9 per cent, clinical Johne‘s disease in 3.9 per cent and chronic peritonitis in 2.97 per cent of dairy animals, manifest chronic diarrhea. The precise diagnosis could not be established in 24.50 per cent of animals. Lymphosarcoma was confirmed in one of the dairy cattle. Body condition score was associated to the etiology of chronic diarrhea. B. coli infected cattle and buffalo revealed cysts in 32.3 per cent cases while 5 per cent positive cases revealed both cysts and trophozoites. Mean cyst count was 2.73±0.91 hpf in diarrheic animals compared to 0.11±0.447 hpf in healthy animals. Clinical Johne‘s disease was confirmed in four animals. Hematological changes revealed anemia and neutrophilia with morphological changes suggestive of regenerative to degenerative left shift. High plasma phosphorus, hypoproteinaemia and hypoalbuminaemia was seen in clinical Johne‘s disease. Salmonella isolates showed higher in-vitro sensitivity to enrofloxacin (87%), ciprofloxacin (87%), gentamicin (75%), and tetracycline (66.7 %) and were resistant to ampicillin and amoxicillin. Mean cyst count reduction from 2.41±1.16 to 0.11±.33 was observed in oral metronidazole treated group where as reduction of mean cyst count from 2.73±0.918 to 0.18±0.44 in intravenous metronidazole treated group. Recovery rate with oral and intravenous metronidazole was 42.1 and 63.1 per cent respectively. Recovery results in significant decrease in eiosionphil count and increase in total plasma protein in both oral and intravenous treatment groups. Complete recovery response approaches 60 per cent in balantidiasis affected adult dairy animals. Balantidiasis was the major cause of chronic diarrhea and intravenous administration of metronidazole was more effective than oral metronidazole.