الفهرس 
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Abstract
The present work aims at studying the efficacy of some untraditional techniques in the control of roof rats, and the protection of non-target birds from the poisoning hazards of rodenticides.
5.1. Effect of potassium tartrate as a repellent agent to protect nontarget birds:
Laboratory studies were carried out to evaluate the efficacy of potassium tartrate (PT), as a repellent agent, in protecting non-target bird species from the poisoning hazards of odenticides.
5.1.1. Addition of potassium tartrate (PT) to crushed maize 5.1.1.1. Effect on quails:
The results indicate that the addition of increasing concentrations of PT to crushed maize has led to a decrease in its consumption and acceptability by quails. A concentration of 16.6% PT has resulted in least consumption of crushed maize.
5.1.1.2. Effect on rats The results show that the addition of 16.6% PT to crushed maize has
decreased its average daily consumption by rats. However, the effect of PT in reducing the daily consumption of crushed maize is greater in case
of quails (26.3% of the pretreatment average daily consumption) than in case of rats (43.4% of the pretreatment average daily consumption).
5.1.2. Addition of potassium tartrate to zinc phosphide/crushed maize bait:
5.1.2.1. Effect on quails:
The results show that the average daily consumption and acceptability of 0.5% zinc phosphide/crushed maize formulation by quails
was reduced to about half their values after the addition of 16.6% potassium tartrate. Mortalities have decreased from 87.5% in case of using 0.5% zinc phosphide/crushed maize formulation to zero% after the addition of 16.6% PT.
5.1.2.2. Effect on rats:
The results show that the addition of 16.6% potassium tartrate to 0.5% zinc phosphide/crushed maize bait has led to an increase in its average daily consumption and acceptability by roof rats and increased
mortalities (100% after 3 days of application).
5.1.3. Addition of potassium tartrate to anticoagulant/crushed maize baits:
5.1.3.1. Effect on quails:
The results indicate that the addition of 16.6% PT to each of chlorophacinone, bromadiolone, and difenacoum baits has decreased its average daily consumption and acceptability by quails.
In case of chlorophacinone and bromadiolone baits, the average daily consumption and acceptability by quails were reduced to about half
their values. No mortalities were recorded among quails before or after the addition of PT to 0.005% chlorophacinone/crushed maize or 0.005% bromadiolone/wheat grain baits.
The 24 hr application of 0.005% ifenacoum/wheat grain resulted in 20% mortalities among quails. The mortality was reduced to zero after the addition of 16.6% potassium tartrate (PT) to the difenacoum bait.
5.1.3.2. Effect on rats:
The obtained results indicate that the addition of 16.6% PT to 0.005% bromadiolone/wheat grain bait has led to an increase in their average
daily consumption and acceptability by roof rats. The addition of 16.6% PT to 0.005% chlorophacine/crushed maize bait for 4 days, on the other hand, decrease the rate of acceptability, and increase mortality among them, under laboratory non-choice feeding conditions.
The addition of PT to chlorophacinone crushed maize bait, under laboratory non-choice feeding conditions, has decreased the longevity of
treated rats since it ranged from 8 to 15 days. The corresponding figures in case of applying 0.005% chlorophacinone/crushed maize bait alone
was 9-19 days, respectively.
5.1.4. Effect of addition of potassium tartrate to 0.005% chlorophacinone bait on rat prothrombine time:
The addition of 0.005% chlorophacinone to wheat grain increased the prothrombine time from 21.7 sec. in control rats to 67.5 sec in treated
one. The addition of 16.6% PT to this bait further increased the prothrombine time from 67.5 sec. to >100 sec. The Addition of PT thus led to an increase in prothrombin time. It is clear that the addition of PT to chlorophacinone bait has synergistically increased its efficacy as an
anticoagulant rodenticide.
5.2. The efficacy of a tracking-edible molasses gel/ 0.5%zinc phosphide delivery system in vercoming bait shyness by roof rats:
The present study was carried out as an attempt to overcome bait shyness developed by rats when they ingest sub-lethal doses of rodenticides. An alternative approach to the control may be to incorporate a rodenticide with gel contaminate. Contaminated rodents would then ingest the toxicant during grooming. Laboratory non-choice and freechoice tests were carried out to evaluate the efficacy of plain molasses gel and toxicant/gel bait.
5.2.1: Non-choice test:
The results indicate that the consumption of plain molasses gel by rats equals 6.63% of individual body weight, while the consumption of
the toxic/gel bait equals 7.54% of individual body weight. The average amount of zinc phosphide ingested by individual rats was 68.4
mg/individual. This amount of zinc phosphide equals 377.38 mg/kg rat.
The acceptability of the gel/toxicant bait was 51.7%. Rat mortality was 75% over 2 days.
5. 2.2. Free-choice test:
The average daily consumption of molasses gel was 49.10% of that of crushed maize. The consumption of plain molasses gel equals
2.92% of individual body weight, while the consumption of crushed maize equals 5.92% of individual body weight. The corresponding
acceptability of molasses gel without toxicant was 32.93%. The average daily consumption of the gel/toxicant bait was 56.67% of that of crushed
maize, since the average daily consumption was representing 2.39% and 4.21% of individual body weight, for gel/toxicant and crushed maize
respectively. The average amount of zinc phosphide ingested from gel/toxicant by individual rats was 21.2mg/individual rats that equals
119.4 mg/kg, this amount was sufficient to kill 50% of tested caged rats.
The acceptability of the gel/ toxicant bait was 36.17% compared with 32.93% for molasses gel alone.
The average daily rat consumption of 0.5% zinc
phosphide/crushed maize bait was lower than the average daily consumption of plain crushed maize alone. The acceptability and mortality were 19.34% and 33.3%, respectively.
The acceptability of 0.5% zinc phosphide/molasses gel bait was about twice that of 0.5% zinc phosphide/crushed maize bait, (it was 36%
and 19% respectively). The mortality among rats exposed to the zinc phosphide/gel bait was higher than that among rats exposed to zinc
phosphide/crushed maize bait (it was 50% and 33% respectively).
5.3. The use of α-chlorohydrin as anti-fertility agent of male roof rats:
The male anti-fertility compound alpha-chlorohydrin (ACH) was tested for the control of roof rats. ACH was provided to rats as crushed maize bait. A mortality of 16.6% occurred after two days of ingesting on average amount of 279.3 mg/kg of ACH, with an acceptability of 19.86%. The concentration used (1%) was effective in producing permanent sterility in surviving caged roof rats. The microscopic examination of the testes and epididymides of rats sacrificed 7, 35 and 60 days after the application of α- chlorohydrin indicated that the testes and epididymides were damaged and the process of spermatogenesis was greatly reduced. Histopathological examination of testes showed severe necrobiotic changes within the semienefrus tubules associated with a necrotic exudate rich in gaint cells within the lumen. Most of semienefrus tubules were free of spermatozoa.
Examination showed an atrophy of the seminiferous tubules with calcinosis in some instances in rats sacrificed after 35 days. In rats sacrificed after 60 days, most seminifrous tubules were atrophied and shrunke with extensive
exfoliation of germ cells into the tubular lumina.
Epididymides of rats sacrificed 7, 35 and 60 days after the application of α-chlorohydrin showed irregular contours of the basal lamina, immature germ cells (with massive numbers in rats sacrificed 60 days) in the lumina of epididymal ducts in many instances. Interstitial edema and vaculations of the epithelial linings of the epididymal ducts, were present in rats sacrificed 35 days after application of ACH.